HomeMy WebLinkAboutSummaryEcological
Flows
Science
Advisory
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August
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2013
Meeting
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Ecological Flows Science Advisory Board (EFSAB)
Meeting Summary August 20 & 21, 2013
Stan Adams Training Facility, Jordan Lake, Chapel Hill, NC
FINAL DRAFT—Approved for distribution
Attendance (for both days unless otherwise noted)
Members
Hugh Barwick, Duke Energy (8/20 only)
Mark Cantrell, USFWS (8/20 only)
Bob Christian, ECU
Tom Cuffney, US Geological Survey
Linda Diebolt, NC League of Municipalities
Chris Goudreau, NC Wildlife Resources
Commission
Jeff Hinshaw, North Carolina State University
Amy Pickle, Duke University
Judy Ratcliffe, NC Natural Heritage Program
Jaime Robinson, CH2MHill
Jay Sauber, NC Division of Water Quality
Fred Tarver, NC Division of Water Resources
Division of Water Resources
Harold Brady (8/20 only)
Tom Fransen
Sarah Young (8/21 only)
Alternates
Rebecca Benner, The Nature
Conservancy (8/20 only)
Tom Gerow, NC Forest Svc. (8/20 only)
Sarah McRae, US Fish & Wildlife
Vann Stancil, NC Wildlife Resources
Commission
Tom Thompson, Duke Energy
David Williams, Div. SWC (8/20 only)
Guests:
Kay Javers, Duke U.
Jen Phelan, RTI (8/20 only)
Gerrit Jobsis, American Rivers (8/20 only)
Jim Mead, Environmental Defense Fund
NCSU Facilitation Team
Mary Lou Addor, NC State University/NRLI
Christy Perrin, NC State University/WECO
Nancy Sharpless, NRLI
The purpose of the Ecological Flows Science Advisory Board: The Ecological Flows Science
Advisory Board (EFSAB) will advise NC Department Environment and Natural Resources (NCDENR)
on an approach to characterize the aquatic ecology of different river basins and methods to determine
the flows needed to maintain ecological integrity.
Presentations, reports, and background information of the EFSAB are available at:
http://ncwater.org/?page=366 (please note that this URL has changed since the last meeting summary)
Webinar Response: If you cannot attend the meeting in person but would like to join us via the webinar,
you can watch the presentations and listen to the live streaming audio of the meeting by going to
https://denr.ncgovconnect.com/sab/ and typing your name in the space labeled "guest."
NOTE: The EFSAB will meet September 24 @9:00am until 4:30pm and @8:30-
4:00pm for September 25 at the Stan Adams Training Facility, Jordan Lake
Educational State Forest Center Chapel Hill, NC (see last page for meeting agenda
topics and directions to location).
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Summary
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Decisions,
Recommendations
and
Proposed
Actions
Decisions and Recommendations:
1. Regarding Flow Recommendations
A. Recommendation 1: Statewide approach using simultaneously two tools:
§ In the basinwide hydrologic models, use 80-90% flow-by as the ecological
flow.
§ If the basinwide hydrologic models indicate that there is insufficient water
available to meet all needs, essential water uses and ecological flows, then
further review is recommended.
§ The Eco-deficit tool should be used to determine the current and future
modeled biological condition of locations in the basinwide hydrologic models.
§ DENR should evaluate the change in current and future biological condition
as a decision criterion. A 5-10% change in biological condition is suggested
as a threshold for further review by DENR. [section requires further
discussion/review by EFSAB to determine if all members can live with/support
this statement].
a. The Board tentatively defined flow-by as: The percentage of ambient
modeled daily flow that remains in the stream. For modeling purposes
this is calculated on a daily basis. [Need to define somewhere how daily
flow is reached].
b. The Board opted to continue fleshing out recommendations and let
writers define terms, then address any concerns about that later.
c. RTI will provide an outline of the RTI report to the EFSAB by mid-Sept for
a review by the EFSAB; include justifications of the 5, 10, and 15%
thresholds to assist with discussion in Sept about the possible threshold.
B. Recommendation 2: Headwater Streams
There is limited biological and hydrologic data in headwater streams within North
Carolina. These streams have a higher vulnerability to disturbance, and the
broader statewide approach may not adequately reflect the potential for impact
to ecological integrity. Therefore, DENR should identify the subset of headwater
streams to receive alternative analysis. (Note for further explaining- examples of
vulnerability, how and in what way. Less water to start could be converted to
intermittent)."
2. Coastal Plain Strategy:
Linda Diebolt will work with Bob Christian to address the coastal plain strategy. This
would include the changes that resulted from the Aug 21 discussion and any pertinent
rationale/assumptions, citations, and references to justify what is being proposed in the
coastal strategy. Writing teams are asked to include other research and literature that
was reviewed and rejected to arrive as this strategy.
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Proposed Actions or Identified Decisions to be made:
1. Regarding Flow Recommendations
1. Another potential recommendation was proposed: The current SIMBASE2013
should be used as the prevailing condition from now forward.
2. Maybe we should advise DWR on how to assess condition of stream, and there
are a couple different ways to do that.
a. Compare against unregulated flow
b. Use eco-deficit tool.
3. When we’re saying to maintain ecological integrity, we’ll at some point define
what it is.
4. Whether or not to set a threshold for %biological change in the recommendation,
and, if so, what that threshold should be.
5. How to move forward between now and September?
a. Address concerns about defensibility/validity
i. Seek report from RTI as documentation (needed)
ii. Seek additional supporting documentation from other studies,
states that could provide references for using indices as
evaluations and particular percent changes (would be helpful)
1. MI paper with table that has water management zones
2. Others?
6. Chris Goudreau will find the MI report to use as a possible reference for
biological change threshold decision.
7. EFSAB members should share any references from other states, studies that
could help with the biological change threshold decision
8. Mark will provide a presentation Sept 24 on how to evaluate the Oasis nodes.
2. Regarding coastal recommendations:
A. Use if/then statements? For example, if DWR wants to pursue scientific
understanding of how to evaluate ecological flows in the coastal plain, then our
advice would be to go through these options.
B. A thorough summary of he coastal work should be included in the report
because the coastal subcommittee's work has been so good, and it mirrors the
work that the whole board has done.
C. Put the research needs into a qualitative description of the if/then statements.
State for your 3 or 4 approaches, how the research needs bolster those. That
would help explain how/why this research is needed.
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Table of Contents
August 20, 2013
August 20 and 21, 2013: Summary of Decisions, Recommendations and Proposed
Actions………………………………………………………………………………………….2
Table of Contents……………………………………………………………………………..3
Executive Summary…………………………………………………………………………..4
August 20, 2013 Meeting Orientation and July 16 & 17, 2013 Meeting Summary
Approval……………………………………………………………………………………….16
Presentation: Defining Stream Sizes……………………………………………………….16
Presentation: Framework of Proposed Recommendations for Coastal Streams and
Rivers…………………………………………………………………………………………..21
Presentation: Recommended Framework for Evaluating Ecological flows in the Streams
and Rivers of North Carolina……………………………………………………………….24
Presentation: EFSAB Report – DRAFT 3…………………………………………………32
Presentation: Concepts and Principles Regarding Ecological Responses to Flows and
Principles……………………………………………………………………………………....33
EFSAB Report Writing Process – Establishment of Writing Teams…………………….35
Discussion on Characterization……………………………………………………………..36
Presentation: Approaches for Setting Protection Standards…………………………….37
Discussion: Continued July Discussions on Development of Flow
Recommendations……………………………………………………………………………39
August 21, 2013
August 21 Meeting Orientation……………………………………………………………...42
Continued Discussion of Stream Size Classification and Headwater Streams………..43
Discussion: Framework for Recommendations in Coastal Streams and Rivers Coastal
Subcommittee…………………………………………………………………………………49
Discussion: Statewide Flow Recommendations………………………………………….50
Revisiting Headwaters Recommendation………………………………………………….57
September Agenda Items…………………………………………………………………....58
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Executive Summary
TITLE: Presentation: Defining Stream Sizes and Discussion of Headwaters
Presenter: Tom Cuffney (Aug 20, 2013)
The EFSAB requested a presentation on the potential ways to define stream sizes and discuss the
merits of each. The presentation was illustrated by the SALCC approach used by RTI/USGS. Tom
Cuffney provided the presentation. The primary purpose of the presentation and discussion was to
look at the issue of how well we’re representing the various stream sizes across the state.
Decisions and Recommendations:
General agreement to have stream classifications in terms of size
Benefit in aligning to SARP and approaches others are using.
Proposed Actions:
Board wants additional data to determine if it’s five classes or combined classes or some other
alternative. Would like to see how the smaller streams fall out from the headwaters. Tom will separate
out and provide new illustration to the EFSAB on Aug 21.
Mark will provide a presentation Sept 24 on how to evaluate the Oasis nodes.
Aug 21: Continued Discussion of Stream Size Classification & Headwater Recommendation
Presenter: Tom Cuffney (Aug 21, 2013)
On Aug 21, the EFSAB picked up from where they left off Tuesday in discussing stream size
classification. The members were asked to review the latest Version of the SALCC drainage area
distribution (a corrected version was reviewed on Aug 21 that separated the headwaters and the
creeks (previously combined) and corrected minor miscalculations). Based on a random set of 900
points, the numbers of the very small basins – less than 3.6 square kilometers – are very under-
represented in the DWQ data. Really small streams tend to become intermittent and thus more
difficult to track and to assess water quality in those systems. These systems require a different set of
standards. With respect to the headwaters, using the RTI, USGS regressions, this reinforces the
notion that smaller and smaller headwater streams are less applicable because these systems
become intermittent, and are totally different. This supports the argument from yesterday to handle
these very small headwater streams differently.
Major Discussion items/concerns/questions:
1. Do headwaters have complete guild assemblages? Vann consistently found fish in ok size streams
2. Is it more appropriate to lump into larger group or keep separate and note the lack of data?
(prefer not lumping)
3. There is data for the headwaters but not for the intermittent streams
4. If applying different criteria, state in the report for headwaters perennials that everything
sampled by DWR/DWQ is proven.
5. What does vulnerability mean?
6. Oasis aggregates small withdrawals criteria; WaterFALL does better in small catchments.
7. If the break were closer to the creek, would that increase the # of creeks? The Geise and
Mason report has a method to identify intermittent streams. [Facilitator's note: upon review of this
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summary, Fred Tarver noted, "I believe Giese & Mason sets drainage areas for Hydrologic Areas (HA)
above which the 7Q10 is not zero.
FOLLOW-UP: “Drainage area, in square miles, below which indicated low-flow statistic generally has a
zero value.” Low-flow statistics are 7Q10/Winter7Q10/7Q2/7Q30. Ten HA’s are delineated in NC in the
report.]
8. The EFSAB may not have enough information but to state small streams are vulnerable.
a. In what ways and how are those vulnerable?
b. Small streams that reach 0 flow experience extreme events naturally; withdrawals add stress
c. example: dead mussels in upper Tar/Sheldon Creek of the Uwharries as creek dries out.
d. Is the impact unnatural given the nature of long-run droughts in the state? What is the
reference condition?
e. Adding a withdrawal factor to stressed systems, extends the period of time of extreme values. This
can be demonstrated on the hydrograph as demonstrated in the Alberta method (a literature source
to conceptually support this claim).
f. Use a different metric and if there is a decrease in flow from perennials – becomes
intermittent – then flag. Another way to add protection.
g. What is the definition of intermittent flows ? 1 day of zero flows (whose definition and can it
be supported?) Biological assemblage should define intermittent. Need to settle on
definition.
h. If there is science that says a withdrawal of 100 mgd from most headwater streams would have a
significant ecological impact, we should say that.
i. Could make statements about dewatering a small stream = impacts; therefore, they need
protection. Though it is unlikely that they can support large withdrawals.
j. Does the EFSAB lump perennial headwaters with creeks?
k. Ecodeficit tool to investigate the potential increase in small streams.
l. Could recommend use of tools in >10km. List of nodes by drainage area to see if any nodes
in <10km drainage? If anything is located in <10km drainage raise a flag?
m. There should be a lot of research showing impacts and vulnerability of small streams.
9. About hydro data and modeling in headwater streams <10 Km. Higher vulnerability therefore
if there is a node in <10km drainage, flag as site specific for follow up. (no gages there to
calibrate Oasis)
10. How to calibrate model and restrictions on OASIS?
11. Do exact same thing without #s – options for recommendations and hard #s where limited
gages (Oasis data)
a. name the description with a range of #s
b. define vulnerability – continuous vulnerability as size increases
c. offer advice not numerical recommendations about relative vulnerability
12. Alternatives to an area
a. actions from perennial to intermittent raises flag
b. 1st or 2nd order stream raises flag (not popular)
c. Condition X triggers a flag if our recommendation doesn’t allow a decision-flow
chart….indicate where to add information if needed.
13. Important to reference impacts to ecology and support these claims.
Decisions Made: Chris, Judy, and Jeff agreed to develop a recommendation for Headwaters that the
group could review and discuss in the afternoon.
Afternoon discussion resulted in the following Recommendation #2 on Headwater Streams:
“There is limited biological and hydrologic data in headwater streams within North Carolina. These
streams have a higher vulnerability to disturbance, and the broader statewide approach may not
adequately reflect the potential for impact to ecological integrity. Therefore, DENR should identify
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the subset of headwater streams to receive alternative analysis. (Note for further explaining-
examples of vulnerability, how and in what way. Less water to start could be converted to
intermittent)."
Proposed Actions or Identified Decisions to be made: none
TITLE: Framework of Proposed Recommendations for Coastal Streams and Rivers
Presenter: Bob Christian
Bob Christian presented a framework for recommendations developed by the Coastal Subcommittee,
which suggests four potential approaches to determining ecological flows for coastal streams,
depending on the origin of the stream, the gradient or slope of the stream and whether the stream has
wind or tidal driven flow:
The subcommittee does not see these as recommendations at this point, but as potential approaches
that could be developed. The subcommittee also developed a list of identified research needs for
developing these into recommendations:
1. Determine correspondence of known discharge patterns with nearby coastal plain stream flow,
stage and floodplain inundation patterns.
2. Evaluate juvenile abundance indices vs. flow and salinity/conductivity.
3. Map salinity distribution across coastal plain.
4. Determine the upper-most extent of tidal influence across coastal plain.
5. Quantify stream typology classes.
6. Evaluate Roanoke slabshell and other mussel distributions and abundance as informative of
salinity and flow patterns.
7. Determine hydrologic metrics and characteristics of coastal streams.
8. Determine reference flow regimes for each river basin.
9. Assess the balance of withdrawals from and discharges to coastal streams.
Major Discussion items/concerns/questions:
• Looking at your stream classification and #5 of the research needs, what percent are covered
by OASIS and not? What are the breakdowns within a class covered and not covered?
o Almost all of it is not covered by OASIS currently.
• In the discussion of coastal rivers and streams, one concern is more about water going into
surface waters after being pumped from an aquifer. An overabundance of fresh water going
into surface waters in the coastal plain has importance for ecological flows, but that is outside
the concern of DWR. [Facilitator's note: Upon review of the summary, DWR disagreed with
the statement that this is outside the concern of DWR, stating that it is a concern if it affects
ecological integrity].
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o That’s in our larger document.
• I’d suggest that the EFSAB would recommend that we push coastal concerns forward with
what it requires. The research needs are appropriate and good for academic concern. But we
have to put it into perspective regarding time and resources to be able to push a
recommendation. It needs a magnitude analysis. I’m most comfortable stating it the way you
(the subcommittee) have: In order to move forward, these are the things that are needed.
• Is the idea that you recommend all 4 approaches and that there would be some hierarchy for
which approach to apply to a given type of stream?
o I would leave these as parallel tracks. Where the statewide approach can comfortably
be extended, that would be the first order approach. But then I think the next best step
is to look at the effects on anadromous fish and other important species and develop
the approaches from the biological point of view. Salinity would be almost a fallback. I
see overbank flow as an add-on; in certain places, the overbank flow is an additional
concern, not an alternate concern
• One of the challenges we are dealing with here is that slope and velocity are not the same;
velocity is incredibly important. It is really the velocity that relates to ecological condition. The
gradients may or may not be indicative of velocity.
o In some ways, though, it is the depth of the stream that determines the amount of
habitat, and in the coastal plain, that is disconnected from the discharge.
• In terms of practical application, if you take it at face value, everything in black, red or turquoise
might fit into the rest of the recommendations.
o Maybe the black and the inland red. I just don't know about the turquoise areas. It may
be that when we look at how to extend the statewide recommendations, the distinction
between inner and outer coastal plain may become a more critical factor.
o Where you have the turquoise areas that are not contiguous with the coastline, they
may be low-head dams or things like that.
• I'm very supportive of dealing with our coastal areas with if/then statements. If DWR wants to
pursue scientific understanding of how to evaluate ecological flows in the coastal plain, then
our advice would be to go through these options.
• I would advocate an integrated whole for the EFSAB report as much as possible. I think a
thorough summary of he coastal work should be included in the report because the coastal
subcommittee's work has been so good, and it mirrors the work that the whole board has done.
I think of it as an integrated whole and encourage us to have a comprehensive report from the
Board at the end of the day.
• I think as much as possible, put the research needs into qualitative description of your if/then
statements. State for your 3 or 4 approaches, how the research needs bolster those. That
would help explain how/why this research is needed.
• When I look at the map of the four classes of streams and the cover slide that shows the
OASIS model area, I think a lot of those that are piedmont, medium-slope are going to be
captured in the OASIS models. If that is the case, then those could automatically go into the
statewide approach. It's not really additional research but rather a next step: overlay those
and see what drops out already.
Decisions Made: none
Proposed Actions or Identified Decisions to be made:
• Use if/then statements? For example, if DWR wants to pursue scientific understanding of how
to evaluate ecological flows in the coastal plain, then our advice would be to go through these
options.
• A thorough summary of he coastal work should be included in the report because the coastal
subcommittee's work has been so good, and it mirrors the work that the whole board has done.
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• Put the research needs into a qualitative description of the if/then statements. State for your 3
or 4 approaches, how the research needs bolster those. That would help explain how/why this
research is needed.
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TITLE: Presentation: Recommended Framework for Evaluating Ecological Flows in the
Streams and Rivers of North Carolina
Presenter: Jennifer Phelan, RTI
There were 2 main components of the presentation:
¥ Flow Alteration – Biological (i.e., flow-biology) response curves for fish and benthos
¥ Ecological Flow (EF) Categories and Thresholds
o Based on “Working Rivers” concept
o Examples within the Upper Neuse River Basin
¥ Where do these curves apply?
The % change of biological condition allowed as a threshold changes based on the current condition of
the stream -- the better condition, the less % change in biological condition is allowed before a flag is
triggered. She showed how this applies in the two example sites within the Upper Neuse River Basin
(Eno River, Goldsboro).
Major Discussion items/concerns/questions:
¥ Concerns were expressed about using the working rivers philosophy
¥ The concept is good for reason of discussion, whether or not the specific proposed categories
and thresholds are used.
¥ Discussion about uncertainty values -- some would like to see them, others point out that the
uncertainty is good for biological data.
¥ Regarding where this could be applied, it was suggested that it could apply everywhere but the
tidal areas.
Decisions Made:
Provide an outline of the RTI report to the EFSAB by mid-Sept for their review; include justifications of
the 5, 10, and 15% thresholds.
Proposed Actions or Identified Decisions to be made: none
TITLE: Presentation: EFSAB Report: Draft 3 - Update
Facilitator: Mary Lou Addor
Chris Goudreau presented Draft 3 of the EFSAB report, which included a new section, titled,
Literature Review and Presentations, and presented additional research information that had been
explored since the EFSAB began meeting. The writing team was comprised of Mark Cantrell, Tom
Cuffney, Linda Diebolt, Chris Goudreau, Sarah McRae, and Jamie Robinson.
Major Discussion items/concerns/questions:
During the Aug 20 meeting, members of the EFSAB were asked for their reactions to the latest
version of the report and specifically regarding the:
1. Level of detail required for the report
2. Organization of the report
Decisions Made:
Ensure Report leads with Findings/Recommendations.
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Proposed Actions or Identified Decisions to be made:
Determine writing teams on Aug 21 once recommendations are developed.
TITLE: Concepts and Principles Regarding Ecological Responses to Flows and Principles
Facilitator: Mary Lou Addor
The EFSAB had been asked to review the section of the DRAFT 3 Report titled, “Flow Regimes to
Maintain Ecological Integrity” (pgs.12-14; this section also referenced a portion of the July Meeting
Summary, pgs 74-78). Presented on pages 12-14, were concepts regarding ecological responses to
flows and principals for maintaining ecological integrity of freshwaters in North Carolina. These
concepts were derived from a list Tom Cuffney presented at the July meeting, titled: ecological
responses to flows.
Major Discussion Items/Concerns/Questions:
During a discussion, several members of the board expressed concern about taking time to review and
develop an agreement about the list versus spending time directly developing recommendations that
would naturally offer context for the discussion.
Decisions and Recommendations:
For the most part, most members were comfortable with the concepts listed on pages 12-14.
Proposed Actions:
Revisit the concepts regarding ecological responses to flows and principals for maintaining ecological
integrity of freshwaters in North Carolina following development of recommendations.
TITLE: Process for Report Writing: Establishment of Writing Teams
Facilitator: Mary Lou Addor
Toward the end of the August 21 meeting, writing teams were established to expand/revise Draft 3 of
the EFSAB report (Aug 16, 2013), in preparation of the Sept 24 and 25 meeting. The main goals are:
1. Provide a rationale for each recommendation developed by Sept 6 (anywhere from 1-3
pages)
2. Ensure the completeness of the document as best as possible. Lou will combine any iteration
into one document with support from Chris and Jamie.
3. Distribute Draft 4 by Sept 10 to the EFSAB listserv so that all members can begin to identify
gaps, areas where they are uncomfortable and why, raise questions, propose alternative
language and additional edits, including how to increase the readability of the report.
4. Receive comments/questions/alternative language/proposals from all EFSAB members by Sept
18 (request earlier return of comments by members working in tandem with their
alternates)
5. Provide marked up copy of Draft 4 with all comments to the EFSAB by Sept 23 (earlier if
possible)
6. Proposal: set aside 2 hours onsite (Sept 25) to make changes to the report moving the EFSAB
closer to one complete report.
Major Discussion Items/Concerns/Questions: None
Decisions and Recommendations:
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The writing teams are:
1. Characterization Recommendation- Chris Goudreau and Linda Diebolt
2. EFlows Recommendation 1 - Statewide approach - Thomas Cuffney and Tom Thompson
3. EFlows Recommendation 2 - Headwaters approach - Judy Ratcliffe and Jeff Hinshaw
4. Coastal Plain Strategy - Bob Christian and Linda Diebolt
5. Glossary - Fred Tarver
6. Reorganization of Report – Jamie Robinson and Chris Goudreau
Recommendations:
1. Characterization Recommendation: Chris and Linda with Tom Cuffney (Tom has an interest in
this section and will do what he can to review). This includes any pertinent rationale/assumptions,
citations and references to justify what is being proposed in the characterization recommendation.
Writing teams are asked to include other research and literature that was reviewed and rejected to
arrive at the characterization recommendation.
2. Eflow Recommendation 1: Tom Cuffney and Tom Thompson will work on this section. This
includes any pertinent rationale/assumptions, citations and references to justify what is being proposed
in recommendation 1. Jennifer Phelan is sending a section of the RTI report that will assist in
supporting the choice of 5%, 10% and the 15% thresholds early Sept. Writing teams are asked to
include other research and literature that was reviewed and rejected to arrive at recommendation 1.
Statewide approach using simultaneously two tools:
§ In the basinwide hydrologic models, use 80-90% flow-by as the ecological flow.
§ If the basinwide hydrologic models indicate that there is insufficient water available to meet all
needs, essential water uses and ecological flows, then further review is recommended.
§ The Eco-deficit tool should be used to determine the current and future modeled biological
condition of locations in the basinwide hydrologic models.
§ DENR should evaluate the change in current and future biological condition as a decision
criterion. A 5-10% change in biological condition is suggested as a threshold for further review
by DENR. [section requires further discussion/review by EFSAB to determine if all members
can live with/support this statement].”
3. Eflow Recommendation 2: Judy & Jeff (Judy may look to Mark, and Sarah to assist). This includes
any pertinent rationale/assumptions, citations and references to justify what is being proposed in
recommendation 2. Writing teams are asked to include other research and literature that was reviewed
and rejected to arrive at recommendation 2.
"Headwater Streams – There is limited biological and hydrologic data in headwater streams within
North Carolina. These streams have a higher vulnerability to disturbance, and the broader
statewide approach may not adequately reflect the potential for impact to ecological integrity.
Therefore, DENR should identify the subset of headwater streams to receive alternative analysis.
(Note for further explaining- examples of vulnerability, how and in what way. Less water to start
could be converted to intermittent)."
4. Coastal Plain Strategy: Linda Diebolt has suggestions for the Coastal section and would like to
work with you, Bob, to address that section. This would include the changes that resulted from the Aug
21 discussion and any pertinent rationale/assumptions and citations and references to justify what is
being proposed in the coastal strategy. Writing teams are asked to include other research and
literature that was reviewed and rejected to arrive as this strategy.
Proposed Actions: None
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TITLE: Discussion on Characterization
Facilitator: Mary Lou Addor
Writing team, Mark Cantrell, Linda Diebolt, Jaime Robinson, and Chris Goudreau drafted a
recommendation for characterization based upon the discussions from the EFSAB at the July meeting.
Major Discussion items/concerns/questions:
¥ Unsure of the relevance of characterization in the way it’s currently reflected in this draft of
report, given that EFSAB did not focus upon it in this fashion.
¥ Make our recommendations and then back up and see what we need to include based on that.
A lot of those answers may come after we have recommendations to provide justification.
¥ RTI and USGS did a lot of work on classification (as a means for characterization). Many
various methods were tried that need to be reflected in the document, but it will be hard to
include until the RTI report is written.
¥ The legislation calls for EFSAB to characterize ecology in the different river basins, so we
somehow need to address that charge in the report, or explain how and why we did not
address it.
¥ DWR staff characterizes the basins when doing basin plans, so we could say that DWR already
does this, and we are focusing on the more critical piece, ecological flows.
¥ Suggest a different way to characterize ecology by basically discussing the relationships
between different flow components and ecology. That stands on its own and we could do that
now in a page or two rather than wait until the last minute. We could find this information in
other documents.
¥ It needs to come out of findings and into a preface section. Its not a finding, but rather it sets
stage for characterizing ecology
Decisions Made: none
Proposed Actions or Identified Decisions to be made:
¥ Chris Goudreau and Linda Diebolt offered to work on the characterization section outside of the
meeting.
TITLE: Approaches for Setting Protection Standards
Presenter: Chris Goudreau
As a lead in to the discussion around developing the flow recommendations, Chris Goudreau reviewed
the general approaches that can be taken for flow recommendations as defined by Richter et al.
(2011). The three approaches defined by Richter include:
1. Minimum flow threshold-- which might be a single value (e.g., 7Q10) or be seasonally adjusted
(e.g., Tennant, South Carolina);
2. Statistically-based standard—this Board has not discussed this type of approach much, but it
attempts to mimic as much as possible all the components of a flow regime, such as:
¥ Critical low, low, high flow pulses, small floods, high floods
¥ Wet, normal, dry years
¥ For each, includes magnitude, duration, frequency, season
¥ Tied to ecologically significant events
o E.g., spawning, floodplain rejuvenation, fry/juvenile growth, migration, sediment
movement, channel maintenance
3. Percent of flow standard (e.g., Alberta)
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Chris then identified which of those approaches were employed by the various trial balloons that have
been presented to the EFSAB. The RTI/USGS (ad-hoc) approach does not fit into Richter’s scheme.
Chris had put this presentation together to assess the various trial balloons in light of the principles that
the EFSAB loosely agreed upon. He then showed how the various trial balloons could be applied to
the various stream sizes used in the recommendations developed in July.
Major Discussion Items/Concerns/Questions: none
Decisions and Recommendations: none
Proposed Actions: none
TITLE: Continuing from July Discussions on Development of Flow Recommendations
Facilitator: Nancy Sharpless
Beginning by looking at the tentative recommendations agreed-upon in July, the EFSAB developed a
new flow recommendation:
Recommendation 1: Statewide approach using simultaneously two tools:
§ In the basinwide hydrologic models, use 80-90% flow-by as the ecological flow.
§ If the basinwide hydrologic models indicate that there is insufficient water available to meet all
needs, essential water uses and ecological flows, then further review is recommended.
§ The Eco-deficit tool should be used to determine the current and future modeled biological
condition of locations in the basinwide hydrologic models.
§ DENR should evaluate the change in current and future biological condition as a decision
criterion. A 5-10% change in biological condition is suggested as a threshold for further review
by DENR. [section requires further discussion/review by EFSAB to determine if all members
can live with/support this statement].”
§ The EFSAB discussed at length whether a numerical range for a threshold for %biological
change should be recommended. This question will be further discussed at the next meeting
The EFSAB developed a list of remaining questions to be addressed and a proposed list of statements
to accompany the recommendation in the report:
Questions to address:
¥ Develop criteria for acceptable % change in biological condition (or do not define?)
¥ Determine if including seasonal differences
¥ How often does it have to drop below for a flag to go up (or let DENR decide?)?
¥ For eco-deficit, use fish or invertebrates?
¥ What level of ecological integrity are the recommendations protecting?
¥ Advise DWR on how to assess condition of stream?
Statements to include in report:
¥ Limitations of data used to develop the eco-deficit tool
o This is already in the report
o When will the RTI/USGS report be published?
¥ PHabSIM could be used when flag is raised.
¥ Issue of it is all modeling—DWR is working in models. Everything is modeled. The
assumptions are based on the models
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¥ It should say it is calculated on a daily time-step
¥ What time step to use in flow-by
¥ How is flow-by calculated
¥ What is the index flow for calculating % flow by
¥ Define terms (%flow-by, eco-deficit)
¥ Include a description of where the high end of the flow-by range would be used.
¥ As data is collected and knowledge develops using the eco-deficit approach, eco-deficit
knowledge might inform changing the % flow-by
¥ Describe where the range of % biological change comes from and authors provide examples of
how it works.
¥ For headwaters, there may not be a node in OASIS. WaterFALL is probably the only tool
available, and it did not correspond well with OASIS. You may not be able to use two tools in
the headwaters because there may not be a node there.
¥ Explain that the model that was done was based on using unregulated flow and based on that
we pick these numbers. Put in a statement that you look at the cumulative effect of
withdrawals and take that into account.
¥ Justification of the flow-by range.
¥ In the Richter paper table 2, FL, MI, ME, EU, those percentages are 80-92.5% flow by. FL is
based on their own information, 80-92%; MI is 85-94%; ME is 90%.
¥ Look at the cumulative effect of withdrawals and take that into account.
Another potential recommendation was proposed: The current SIMBASE2013 should be used as the
prevailing condition from now forward.
The EFSAB had much discussion as to whether to provide a number or range as a threshold for %
change in biologic condition or to not provide a number or range.
Why not to provide a number or range as a threshold?
• Is recommending a % change recommending a policy decision?
• As a group we have different understandings and interpretations of the threshold
concept of the ecodeficit model.
• DENR should have the capacity to determine a threshold themselves
• Authors should be able to provide a recommendation and justify it rather than the Board
setting that point.
• Is it defensible since there is no report from RTI yet, and no publication?
Why provide a number or range as a threshold?
• If saying DENR should consider change of biological condition between current and
future as a decision criterion, without guidance on how to interpret what is allowable
% change, nothing may happen with it.
• PHABSIM approach would also require an allowable % change to be used as a
decision criterion.
• If x% is recommended as an initial threshold with some explanation of why we chose
the #, it’s at least a point of discussion. If it’s ignored, at least we’ve gone down with
some number and some reasoning.
• Would allow us to frame it as a risk of change if more than this % change happens, to
say further review warranted when this threshold is crossed without defining a
specific action of DENR.
• DENR needs some context for what a % change in bio condition would amount to, and
risk of change in EPT class is most logical (criteria with which to evaluate the
magnitude of change).
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Board members present liked the biological index approach presented by RTI/USGS, but consensus
was not reached on whether or not to set a threshold in the recommendation, or what that threshold
should be.
Options
¥ If Board cannot reach consensus on a threshold, we can recommend DENR decide on a
threshold
¥ Ask authors to provide a number recommendation and then Board refers to it rather than
making the recommendation directly.
¥ Board can provide a number/range as an initial/starting point threshold for DENR to use.
¥ If we spent more time with it, with more examples may give us more confidence in a threshold
(wait for RTI report?)
A range of 5-10% change in biological condition was suggested as an initial threshold.
¥ Include an explanation of where numbers came from within the report.
¥ Ask authors to provide examples, advantages, disadvantages of the numbers
¥ In report include language about when you may want a higher % change, when a lower %
change may be appropriate
¥ A straw poll of a proposal to use 5-10% as a threshold resulted in one-1, seven -2’s, and two
4’s
¥ A straw poll of a proposal to use 5-15% as a threshold to reflect the RTI presentation was
polled resulting in three-5s, so this was not further considered
o It would not work to apply 15% across the board as a way to reduce risk
Decisions Made:
1. Recommendation 1: Statewide approach using simultaneously two tools:
§ In the basinwide hydrologic models, use 80-90% flow-by as the ecological flow.
§ If the basinwide hydrologic models indicate that there is insufficient water available to
meet all needs, essential water uses and ecological flows, then further review is
recommended.
§ The Eco-deficit tool should be used to determine the current and future modeled
biological condition of locations in the basinwide hydrologic models.
§ DENR should evaluate the change in current and future biological condition as a
decision criterion. A 5-10% change in biological condition is suggested as a threshold
for further review by DENR. [section requires further discussion/review by EFSAB to
determine if all members can live with/support this statement].”
[The EFSAB discussed at length whether a numerical range for a threshold for %biological
change should be recommended. This question will be further discussed at the next meeting]
2. The Board tentatively defined flow-by as: The percentage of ambient modeled daily flow
that remains in the stream. For modeling purposes this is calculated on a daily basis.
[Need to define somewhere how daily flow is reached].
3. The Board opted to continue fleshing out recommendations and let writers define terms,
then address any concerns about that later.
Proposed Actions or Identified Decisions to be made:
1. Another potential recommendation was proposed: The current SIMBASE2013 should
be used as the prevailing condition from now forward.
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2. Maybe we should advise DWR on how to assess condition of stream, and there are a
couple different ways to do that.
a. Compare against unregulated flow
b. Use eco-deficit tool.
3. When we’re saying to maintain ecological integrity, we’ll at some point define what it is.
4. Whether or not to set a threshold in the recommendation, and, if so, what that threshold
should be.
5. How to move forward between now and September?
a. Address concerns about defensibility/validity
1. Seek report from RTI as documentation (needed)
2. Seek additional supporting documentation from other studies, states that
could provide references for using indices as evaluations and particular
percent changes (would be helpful)
a. MI paper with table that has water management zones
b. Others?
6. RTI will share the proposed outline of their report to the EFSAB for feedback about what
should be included, and will complete a description of the biological change threshold
methods and reasoning before the September meeting.
7. Chris Goudreau will find the MI report to use as a possible reference for biological
change threshold decision.
8. EFSAB members should share any references from other states, studies that could help
with the biological change threshold decision
I. August 20, 2013 Meeting Orientation and July 16 & 17, 2013 Meeting
Summary Approval
Members and alternates of the Ecological Board Science Advisory Board introduced themselves and
their affiliations. Guests in attendance and the facilitation team also introduced themselves.
Everyone was reminded to sign-in who attended the meeting.
A brief orientation was conducted of the meeting facilities (restrooms, concession) and available
technology (webinar). Members and alternates are encouraged to sit at the main meeting table and
guests at tables away from the main meeting spaces. During discussions of the members and
alternates, guests may comment once members and alternates have completed their comments and
questions. During small group work, guests can also participate in small group discussions but may
not dominate the time. Everyone is asked to ensure that space is created for others to engage. From
time to time, the facilitators will conduct a straw poll to determine the current level of support for an
idea or what additional information is needed, not necessarily for a final decision.
The EFSAB approved the July 16 & 17, 2013 meeting summary, and it has been posted to the NC
Water.org website.
II. Presentation:
Defining
Stream
Sizes
Presenter: Tom Cuffney, USGS
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The EFSAB requested a presentation on the potential ways to define stream sizes and discuss the
merits of each. The presentation was illustrated by the SALCC approach used by RTI/USGS. Tom
Cuffney provided the presentation. The primary purpose of the presentation and discussion was to
look at the issue of how well various streams sizes are represented across the state.
Fred opened the discussion of stream classification by introducing a map that Ian McMillian had
developed though it was not clear how this map related to stream sizes. The map displayed public
water intakes, NPS discharges, and USGS gage sites, including the blue line streams in the state. Ian
was demonstrating the distribution on the various intakes and discharges in relationship to the gage
sites.
In terms of stream size in headwater streams, the goal was to address the relationship of these
registers at various intakes and discharges in relationship to discussions about headwater streams
versus larger streams. Recall that the use of bug and fish data primarily comes from wadeable
streams; that larger non-wadeable streams are probably going to be the existing intakes and
discharges in the future and thus candidates for additional withdrawals. And so, in terms of intakes
and placement of these intakes and discharges, the locations in these non-wadeable streams and
lower reaches and to some extent the headwaters are not typical sites for proposed new intake due to
dependability of water supply. The public water supply doesn’t account for non-registered withdrawals
such as with agricultural or other sources.
In terms of relationship to the OASIS models, DWR uses the USGS gage data to calibrate the OASIS
models. In terms of location of the nodes placements in the OASIS model, they’re placed in areas that
try and capture registered water uses (registered with DWR in terms of greater than 100,000 gallons,
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or those shown on the map here). Thus, we try to capture those nodes. In some of the other
headwater streams, there are not nodes because there are no known withdrawals that meet the
criteria of greater than 100,000 gallons.
With respect to discussions about headwater streams, DWR does not have that resolution in its use of
OASIS to capture some of the headwater streams, because there are no uses, or are no known uses.
Question: Is there a way to analyze or augment the blue lines? Because the wadeable streams area is
not necessarily so small; a few of these areas are staying full. Can we acquire concrete numbers?
Tom: In terms of how far up the headwater streams, maybe the Board can consider
recommendations on evaluating headwater flows and headwater streams. But in terms of the OASIS
model, the very upper headwaters are probably not captured.
Question: Does the legislation have a cutoff point for stream size? [No] For ecology or
characterization?
Tom: No, it’s very broad. The Board is free to make recommendations as it sees best.
Comment: Some of the best water supplies are in these smaller headwater streams and in multiple
headwater streams. If there are limits on withdrawals in some waters, then it leaves open the door to
the headwaters.
Tom turned the conversation toward what was currently available to the Board in terms of water or
basin size classifications. He presented a distribution of streams pulled together by the SALCC and
used by RTI and USGS. The distribution is comprised of headwaters, creeks and small rivers, medium
rivers, mainstream rivers, and large rivers, which are greater than 10,000 square kilometers.
[Note: Tom had initially combined the class 1a – headwaters and 1b- small rivers].
A question raised to the group was, “Do we agree to have stream classifications in terms of
size?” [Yes].
The second question is whether 1, 2, 3, 4, 5 classes – are acceptable, or whether some should
be collapsed similar to what Chris had, or some other alternatives. Originally, the work TNC
completed in the northeast involved extensive analyses, a panel of experts, and how different states in
the northeast defined their sampling regimes. The results made sense from a data distribution and a
utilization perspective. SARP and the South Atlantic LCC have picked up this work. Thus it’s fairly
widely used.
Tom further explained that the BEC analysis made use of the fish sites and the use of random points
across the state to define basins. Random points were set up for comparisons to the biological, as
opposed to gage sites; the biological sites do a very good job of reflecting the distribution of these
streams across the state in terms of numbers. This was the point in using those random sites- to
provide a level of criteria to look at. This random population helps to indicate how well we are doing at
representing streams conditions across the state.
The argument about whether we’re representing the mainstream sources where most of the water is
being taken out – is a different question. It needs to be addressed both in terms of the biology, and in
terms of the charge to the group, which does not necessarily say its drinking water withdrawal in large
rivers. But it says basically, all streams in the state. So again, do people agree that this shows that
we are representing the distribution of stream sizes across the state biologically?
Comment: Yes, this seems reasonable. However, I’d be more comfortable if the headwater creeks
were separated from the headwater streams. I’d like to see how they fall out in terms of biology.
There’s a bigger difference between a stream with average mean flow less than 10 CFS compared to
one that might have average mean flow of 75. I’d like to see if it’s representative. We may want to put
them together or we may not. Are we trying to keep certain streams pristine? If so, we might be more
inclined to say headwaters or creeks.
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Additional comment: do not over focus on the adjective of headwater, creeks, small rivers rather than
the numerical distribution. For example, you’ve got 5 categories which are 100% based on drainage
area. (We could debate for a long while the adjectives that describe the drainage areas, as to whether
that’s really headwater or whether it’s a small creek).
Response: when you include the really, really small creeks, you’re including everything down to those
that are ephemeral. I believe there’s much greater difference perhaps in the biology of those compared
to the biology of those that are not that small. Let’s break them out and see what we get – Tom said he
could do that after lunch [was unable to do this until the next morning].
Distribution of Stream Sizes
Drainage area (km2) No. fish sites No. Inv sites No. RndPts All sites
Headwater & Creek: < 100 701 1124 778 2603
Small rivers: 100 – 518 154 409 67 630
Medium rivers: 518 – 2,590 3 130 36 169
Mainstem rivers: 2,590 – 10,000 0 42 12 54
Large rivers: >10,000 0 17 7 24
Total 858 1722 900 3480
Stream sizes: Biol. Vs. Random
The next issue, where does representing the OASIS nodes come in and how do we assess the
importance of that?
We may need to consider some type of analysis that we did with fish sites and say where are the
nodes now? How many nodes fall where? Is that doable? Like where are they on these streams?
Are they meaningful, or medium rivers or greater? I think that would match up with what we’re going to
hear.
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Comment: The difficult part would be to geo-reference the nodes, because they capture a withdrawal
or a discharge or a combination of such. So you have to kind of refer back to what the node’s trying to
capture in order to try and get a placement of it in general. So you’d have to go back and see what
each node tries to represent in terms of the model. And then, based on the NPS permit for an intake
that long, you’d have to say the node is here. Since we don’t have weights and nodes for all basins,
we’ll just go back to the raw data, which are the intakes and the discharge ones.
What is the explanation as to why some of these categories are rolled together? When Mary Davis
was doing the analysis for SARP, the northeast design was here’s the stream and you can collapse or
not based on individual needs. Jeff’s point is a good one. They are ecologically different so it will be
helpful to see if there are distinctions.
For now, I think we are doing a good job spatially and have addressed the issues in terms of
characterizing responses or ecological flow across the state. But we have another question, which
DWR is really interested in. What is the effect on these larger rivers that they’re likely to increase
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withdrawals from? We don’t really know what the overlap is between the sites the models were built
for and the sites DWR is interested in. It’s a supplementary question that may be a bit beyond the
charge although it’s relevant to DWR and their tasks.
The take home message, for me, is that the areas’ classifications haven’t been as important as a
general response across all of the classes of rivers as- within an eco-region of some sort.
The BEC analysis said that we can’t divide them by eco regions, need to conduct statewide. That’s
consistent with what we’re seeing here, that the applicability of this model is over most of the state,
though it may not be very applicable at the very low or very high end.
Facilitator: Mark has volunteered to try and pull the raw data together to determine where the Oasis
nodes come into the analysis.
Some general comments about the stream size classifications:
1. General agreement to have stream classifications in terms of size
2. Board wants additional data to determine if it’s five classes or combined classes or some
other alternative (Tom will provide this review).
3. Benefit in aligning to SARP and in approaches others are using.
[Concluded Aug 20 Discussion on Stream Size Classification]
III. Presentation:
Framework
of
Proposed
Recommendations
for
Coastal
Streams
and
Rivers
Presenter: Bob Christian, ECU
This power point presentation can be found here
Bob Christian reviewed the overall objectives of the Coastal Subcommittee, which include:
• Assessing applicability of previous coastal work (other states and Greenville)
• Developing a stream typology
• Advancing spatial modeling and mapping
• Establishing relevant ecological and biological dependencies on flow
• Developing frameworks for potential coastal ecological flow criteria and protocols if possible
• Identifying factors limiting coastal ecological flow protocols and needed research within coastal
systems.
Bob showed the stream typology developed.
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The subcommittee concluded that whether a stream is in the upper or lower coastal plain was not
significant in terms of determining ecological flows. Rather, the subcommittee determined that the
important issues are: origin, by reach; gradient/slope, dividing streams into medium slope (.2.51m/m)
and low slope (<2.50mm/m); and tidal effect (below 1 meter elevation). The subcommittee mapped
which coastal streams and rivers are in each of those categories:
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They then developed a framework of potential approaches for determining ecological flows based on
those:
For the streams originating in the piedmont, the subcommittee suggests using the EFSAB
recommendations developed for the rest of the state, applying those downstream as far as possible
with the understanding that there is some regional correlation, noting that at this point the
subcommittee can not define the % correlation between upstream and downstream flows.
A discharge and habitat approach could be developed for medium and low gradient streams.
Information from fisheries and other agencies could be used to develop quantitative relationships
between flow and habitat from which to make numerical recommendations. Several states have used
downstream salinity as an approach to ecological flows in coastal areas. Actual numbers would need
to be developed to apply in NC. Finally, Bob noted the importance of overbank flow in riparian
wetlands.
Additional research is needed to develop quantitative approaches for determining ecological flows from
this framework of recommendations. The coastal subcommittee identified the following research
needs:
1. Determine correspondence of known discharge patterns with nearby coastal plain stream flow,
stage and floodplain inundation patterns.
2. Evaluate juvenile abundance indices vs. flow and salinity/conductivity.
3. Map salinity distribution across coastal plain.
4. Determine the upper-most extent of tidal influence across coastal plain.
5. Quantify stream typology classes.
6. Evaluate Roanoke slabshell and other mussel distributions and abundance as informative of
salinity and flow patterns.
7. Determine hydrologic metrics and characteristics of coastal streams.
8. Determine reference flow regimes for each river basin.
9. Assess the balance of withdrawals from and discharges to coastal streams.
Bob indicated that APNEP and Division of Marine Fisheries might be able and willing to carry this work
forward.
Comments/Questions from the EFSAB included:
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• There is a salinity map available
• There are models for Neuse, and Tar/Pamlico, that could be used that hydrodynamic models
o That was used for the Greenville study
• Looking at your stream classification and #5 of the research needs, what percent are covered
by OASIS and not? What are the breakdowns within a class covered and not covered?
o Almost all of it is not covered by OASIS currently.
• The Lumber River has not been attempted, but there are some gages there.
• Some of the Cape Fear could be modeled.
o There are gages on the system that are not being modeled?
o Yes, there are some gages.
• NCSU has done correlations of flow at different water level stations along the Neuse.
• In the discussion of coastal rivers and streams, one concern is more about water going into
surface waters after being pumped from an aquifer. An overabundance of fresh water going
into surface waters in the coastal plain has importance for ecological flows, but that is outside
the concern of DWR. [Facilitator's note: Upon review of the summary, DWR disagreed with
the statement that this is outside the concern of DWR, stating that it is a concern if it affects
ecological integrity].
o That’s in our larger document.
• So in terms of recommendations, at this point your group is recommending that we have a
piece in the report that says, we don’t have enough information to make a quantitative
recommendation, but here are some options.
• I’d suggest that the EFSAB would recommend that we push coastal concerns forward with
what it requires. The research needs are appropriate and good for academic concern. But we
have to put it into perspective regarding time and resources to be able to push a
recommendation. It needs a magnitude analysis. I’m most comfortable stating it the way you
(the subcommittee) have: In order to move forward, these are the things that are needed.
• The process is beyond; here are the research needs.
IV. Presentation:
Recommended
Framework
for
Evaluating
Ecological
flows
in
the
Streams
and
Rivers
of
North
Carolina
Presenter: Jennifer Phelan
This PowerPoint presentation can be found here
This presentation is to place those in a framework to recommend a setting for evaluating flows
throughout the state.
2 main components of presentation:
¥ Flow Alteration – Biological (i.e., flow-biology) response curves for fish and benthos
¥ Ecological Flow (EF) Categories and Thresholds
o Based on “Working Rivers” concept
o Examples within the Upper Neuse River Basin
¥ Where do these curves apply?
These categories based on working rivers concept I’ll explain. We had requests from you to see it on
the ground to see it applied- we’ll show the flow metrics there and translations into metrics that makes
sense (million gallons per day or MGD), which may make more sense than ecodeficit. We used two
examples in the Upper Neuse River Basin and will translate ecodeficit into units that may make more
sense.
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Second component, where do these curves
apply.
Flow biology curves- here we show the curves
for benthos and fish, reminder the biological
response metrics for benthos is EPT Richness.
The biological response metric for fish is the
riffle-run fish guild characterized by the Shannon
Weaver Index for species diversity and
abundance.
Something else to get out of here is the fact that
fish seem to be more sensitive to flow
alterations than benthos, as least riffle-run fish
guild.
Now putting this in a framework of ecological
flow categories and thresholds onto the curves.
Here are definitions to start off with, and then
we’ll put them on a curve.
EF Category = Current biological condition that determines EF Threshold
EF Threshold = Change in biological condition (caused by flow alteration) that triggers a “flag”,
meaning the biological component has been compromised.
This table outlines the 4 categories we’re proposing- current condition is based upon the WaterFALL
model that tries to look at change in biology that changed based on flow, current is the baseline. That
varies across the state, the change in natural vegetative cover to current condition.
Q: what you’re suggesting, the threshold is the greater the degradation of the stream, the greater the
tolerance?
R: yes.
For each category, we recommend an amount of absolute change that can occur in each class. If you
have a relatively good condition with respect to flows, the condition could be altered 5%, etc. This is a
working rivers concept- we’re proposing, and would like your feedback on this, that a greater level of
protection to the streams and rivers that are in good condition. To put this framework onto these
curves to see what it shows.
Q: the threshold is based on an arbitrary weighting decision based on a philosophy, rather than a
tested model?
R: yes, the relationships are linear, there is no place on the curve where it drops off; it is an
incremental change.
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Q: You could have equally made those the same. Based on this threshold with the arbitrary value
judgment, we could equally have made it 10 or 12% or any other figure.
C: To clarify, for the 80-60 category, that’s not 10+ 5, it is a total amount (in the right hand column)?
R: Yes. Basically if you are saying the current condition is 70%, than it could go down to 60%.
Q: How do you reconcile working rivers concept of allowing additional degradation to existing
condition when you have the Clean Water Act that requires… healthy balanced… (inaudible)
C: The concept is likely that this is an ecological flows decision and not a threshold of what meets or
doesn’t meet water quality standards. Those are 2 different models of planning and assessment.
Nothing in the legislation is about water quality.
C: It’s not the same metric of impairment used by DWQ. A 60% condition may not be an impaired.
Q: Aren’t’ they related? The more water you take out the higher the concentration of any pollutants?
C: She is suggesting a tolerance of change, not a threshold of what’s acceptable and not acceptable.
C: Planning not permitting is the mantra- this is not a regulatory decision, it will be up to DWR to
determine the threshold of what the response is based on the category.
C: Legislation has nothing about working rivers in it, but maintaining ecological integrity. In terms of
what our mandate is, there may be a problem with this.
C: It does say “prevailing eco condition”.
C: Not necessarily the prevailing economic condition, but back to ecological integrity.
C: But the way it’s proposed is appropriate but we would need to make sure the caveats are
explained. The 3 categories could be for different levels of warnings for planning purposes.
C: We did discuss having the same number across, but for those in good shape now, would we want
to give them extra protection?
C: You’re dead on target, but that would be a different decision than a planning tool. That would be
decision-making.
C: Whatever the numbers are would be dealt with at the next stage. The concept is good for reason
of discussion.
C: In terms of thresholds, can we detect a 5% or 10% change? Are these measureable differences?
R: I’ll show you and you can decide.
We’re trying to apply these categories and thresholds to eco-deficit. Here are categories placed on the
curve, the x-axis is % ecodeficit, current biological condition in y axis. If you translate what the
categories correspond to in terms of ranges of ecodeficits, you can get these categories of conditions
in the colored boxes.
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Can you name a river or stream you’d expect to have minimum altered flow?
C: Lumber
R: Say for example the Lumber has a 6% current eco-deficit, using WaterFALL to see current level of
flow alteration. The gray dot is where the Lumber falls. If it has current biological condition of 85.8%,
then say if we allow a 5% change in biology going down the slope, which corresponds to an 8.1%
ecodeficit (2.1% additional ecodeficit). Look at it and let me know if you have any questions.
This is a direct translation of these 4 classes (shown in colored areas in SLIDE)
Q: it’s not a 5% change in ecological flow, but in biological condition?
R: Right, and entirely determined by your flow biology curve.
Q: Are you going to go further with your model river and translate that into the flow pattern that
correlates with that change in threshold of eco-deficit?
R: You may get a glimpse of that when we start looking at the Upper Neuse River basins.
C: You go to 6% on the horizontal axis, which goes up to 85.8 current biological condition, which puts
you in blue category. Then allow 5% change in bio condition, which brings you down to at 80.8 on the
vertical access, which translates to 8.1 on the horizontal, which is a net change from current to
projected ecodeficit change.
R: Yes. This is for fish. Relationship is stronger (slope is steeper) with fish you can see the ranges
for categories are slightly tighter due to more sensitivity to flow. The ranges for your categories are
slightly tighter.
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Question: Is it required to use WaterFALL to determine biological condition %?
C: Only thing is you have to have a way to determine baseline condition, and you could map the entire
state using WaterFALL.
Q: Have you put in any uncertainty values? When those original regressions were made, the fit
wasn’t great, a pretty large uncertainty band. Have you looked at the confidence intervals? What
might it be in this example?
R: yes, there is a large band, true.
C: no, important to remember this is your red flag tool, to red flag things you need to look at further.
This is a planning tool, not predictive with absolute values. The confidence Intervals are not bad for
biological data.
C: I just like to see the uncertainty of the curves.
C: The confidence intervals are not that bad for biological data.
C: It’s helpful to think it’s about making comparisons on DWR’s large planning horizons, 25-50 years
out. It’s not on a request-by-request situation. It’s at such a high level in the planning, that this
movement between EF categories will be at a high level. It will take potentially a high withdrawal to
move it.
Back to Jennifer’s presentation: Here are the examples.
¥ Locations:
o Eno River State Park stream segment
o Goldsboro river segment
¥ Scenarios (flow metrics and associated biological condition):
o Current Condition = WaterFALL PNV (natural vegetation)– 2006
o Projected 2050 Condition = OASIS current – 2050
o EF Category and Threshold = determined by flow-biology curve
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¥ Flow metrics and million gallons per day (MGD); Jennifer showed and explained slides -
Applications given real world examples (see slide)
Putting the framework of EF category and threshold and putting them on the curve to show how
proposed projects relate to the categories and see if they exceed our comfort level and raise red flags.
Translate it to MGD.
Starting with Benthos- current
condition, Eno segment is
relatively pristine with respect to
flow alteration; Goldsboro is
quite modified. This is 2050
projection based on OASIS
estimates, associated eco flow
%’s, and MGD for summer
season; keep that in mind.
There is a big difference due to
the size of streams.
Plot the allowed biological
change of 2.1% with Eno, a red
flag goes up because 2050
projections will exceed
allowable amounts of change in
biology. In contrast with
Goldsboro, it’s in a different
category, and does not cause a
red flag.
The same thing happens with fish, though slightly more sensitive; again the red flag goes up for the
Eno but not for Goldsboro.
Any questions here?
Q: just a reference point, at point where you measure Eno, what is flow typically there at that point?
C: It’s about 100 square mile drainage area, 1 cfs per square mile for flow for the year.
C: so on the Eno, that .43 MGD, is about .75 CFS.
R: these MGD, if you were to permit another withdrawal to occur, and how much you think a utility or
facility would want to withdraw on a daily basis, and how these values equate to that.
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Here is the summary of the different flow metrics that have been presented. The 4 eco-deficits based
on season, the 30-day min flows. For Eno and Goldsboro, and biological condition (benthos on right).
Idea is to contrast the 2 different river sizes and how minimum flows convert to MGD. There is a
difference by season and river size. Here you can see for benthos this is current condition based on
curves for benthos, and 2050 projections.
Q: Help me to understand how you generate benthic condition?
R: Continue using the benthic curve relating the amount of flow to % change. Summarize all the curve
condition, plot it on the curve, allow 10% change, plot it, and see where change is on the curve. This
is entirely based on triangulation.
Q: This can design how well we’re able to measure ecodeficit?
C: It’s a function of your slope and your confidence in the slope (and assumption of linearity). They did
look at it non-linear and the fit was similar.
C: I think it’s straightforward. Only wording differences I’d make are that you’re not really proposing
thresholds, your proposing relative changes. DWR could choose something different, such as
moderate change, minimal change.
R: Yes, the terms you use could be very loaded. This is a proposed framework, could put the flow
biology curves, how you could translate them into some kind of recommendation for how you want to
address thresholds.
C: The metric-- winter spring summer fall--those are all flow duration curves…it’s the median flow
duration curve.
C: Fundamentally it’s a risk analysis (which makes sense)
R: Current eco-deficit is a relationship between current condition curves (using 40-year period of
record, same as used in natural vegetation and current) so you only get curves based on human
influence.
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C: What I’m struggling with, I’m glad you used Eno, it’s already a capacity use area, has been
recognized as a flow vulnerable area, but yet it’s coming out in the high category of good biological
condition. It seems to be a mismatch and I’m having trouble reconciling it.
C: A couple things- you’re right the Eno is a voluntary capacity use designation- it doesn’t mean it’s
going to hell, it means there is a threat to it. There is concern about Eno due to the state parks; there
are a lot of straws in it. You’ve got 2 reservoirs in headwaters, water supply, out of basin transfer, it’s
tiptoeing along the edge. But last time we were there was a DWR investigation to see if it qualified for
high quality waters. That it comes out in the upper category isn’t that surprising. It doesn’t seem high
on that graph but it is a lot for the Eno. There’s not a lot of water, it doesn’t take much for withdrawals
to have an effect.
R: this is the same for fish. The eco-deficits don’t change as it based on flows and landscapes, and
these are the biological curves for fish.
Moving on to the next and final component. Anything else first?
C: if folks are getting wrapped around what we call these classes of existing condition, take that away,
and say x%, you start here, you allow x% change, whether its different numbers. The concept is good,
we could argue over details later.
C: We don’t have to embrace the working rivers concept to use this. The management can decide
their threshold; this provides a relative level of risk as a planning tool to describe this.
Back to presentation:
Finally, where do these curves apply- the distribution of the fish and benthos monitoring sites,
exactly same as what Tom put up today, versus summary of what all the catchments look like for the
state. It more or less represents distribution of drainage areas across the state. For fish it’s not as
well, but we recommend the framework for all rivers and streams until more data is available.
Any questions?
C: It could equally be altered to represent if/then scenarios. If you exceed 15% or whatever risk
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threshold, it could require site specific evaluation. Jordan Lake is about 1400 square miles for
reference.
Q: could this be applied about crossing a category, so if you had a system like Eno and the red flag
went up, could you look at it if you are going to move that system further into next category, could you
backtrack what threshold will cause us to shift into the next condition?
R: You can make it so it jumps into next category, but the problem is you can get so the point is so
close to the threshold, you don’t have to have much change in flow to jump into the next category.
That’s the problem with absolute categories. We didn’t want to make absolute categories, but rather
base it on current condition. It doesn’t matter where you start, you can always add more on. Do we
want to apply 10% to rivers in good condition? Determine where you are initially, and then apply a
value to the current condition (a % change). Allows an acknowledgement of where you stand, and
then based on that you allow a certain percent change based on current condition.
C: It would be nice to calculate what an error value would look like. How much of a change to have
statistically significant. Example, a 10% change, how many standard deviations is it, what would be
confidence limit.
C: A more relevant question, is it a significant difference. It’s probably more like a 50 or 40% chance
you’d have that change.
C: The actual amount is less important than knowing whether a difference that you see is related to
some level of variation within the population, right?
C: Expressed another way, you could say we’re 90% confident that we’ll alter the biology.
C: Exactly, rather than just saying a 10% difference. Another way of wording the 5- 10- 15% change
in the proposal.
R: We debated probabilities, too.
C: We need to get away from the 95% confidence interval. If you can prove 50%, you are responsible
to that. We do a disservice by sticking to the 95% confidence interval, then you have drastic change.
Think about the risk instead. To give you an idea of variability of slope for EPT Richness, slope is
2.35, standard of error is 4.199…it’s not that bad (similar to fish too). There’s no R-squared.
C: Recommendation was for all streams, based on Bob’s presentation in terms of coastal waters, that
would answer if this applies to coastal. Do the curves apply for streams where we don’t have data?
C: We do have data. The majority of the actual difference of ecological deficits is in the coastal plain.
C: It might apply to medium gradient.
C: Question for DWR, what are the boundary conditions for the models you’re working on in terms of
the coastal area? Is that question even relevant?
C: The terminal node is associated with lowest gauge that is non-tidal.
C: Most of coast would not be included in the model.
C: The statute is more expansive than the modeling efforts.
C: Here’s a situation, if you have a gauge downstream of where OASIS ends but there is good
correlation to discharge factor, you might be able to apply it downstream. Wouldn’t be able to apply it
to additions of freshwater (reducing the ecodeficit).
R: That would be part of your modeling effort to account for. Example here, for 30-day minimum flow
metric for Goldsboro was not applicable because there wasn’t a reduction, but was an increase.
C: Regarding applicability, a lot of streams are ungaged. We don’t have the hard-core gauge data for
them, so if it’s a physical characteristic like size and you can guess basin size, why wouldn’t you apply
it? There are some pieces of information we have, we may not have biological data or gage data, we
could say this is a medium river, and apply it because we don’t have any information saying it wouldn’t
apply. All the mapping you did it sounds like ¾ of streams fit into the basic size classes. Tidal could
drop off.
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V. Presentation:
EFSAB
Report
–
DRAFT
3
Facilitator: Mary Lou Addor
A writing team composed of Chris Goudreau, Mark Cantrell, Tom Cuffney, Linda Diebolt, Sarah
McRae, and Jamie Robinson developed Draft 3 of the EFSAB report. Chris Goudreau presented Draft
3 of the EFSAB report, which included a new section titled, Literature Review and Presentations,
and additional research information that had been explored since the EFSAB began meeting. The
drafting team also included a section on Characterization that they were asked to write from the July
meeting.
This section will focus on the discussion about the report. During the Aug 20 meeting, members of the
EFSAB were asked for their reactions to the latest version of the report and specifically regarding the:
1. Level of detail required for the report
2. Organization of the report
Comments regarding Organization of the Report included:
1. In general, organization of the report is fine
2. Ensure report leads with what people care about – the Findings/Recommendations
3. Discussion ensued about ensuring the main body was concise and relevant to the outline, that
supplementary details are provided in the Appendices or linked to the appropriate materials on
the DENR Water.org website.
4. The EFSAB will consider the value of an external reviewer before submitting a report to DENR
(Linda Diebolt can recommend an external reviewer).
5. Consider how the report can use 21st Century technology and make use of the DWR website
as an accompaniment to the report (take report into the 21st century)
Comments regarding Level of Detail Required for the Report included:
1. Audience is DENR the institution; DWR is expected to produce the reports required by the end-
users like the EMC, the General Assembly, or the public. Therefore, the report from the EFSAB
should be of sufficient length to present the rationale behind the recommendations presented
by the EFSAB. This includes all of the information examined by the EFSAB, and specifically
what information laid foundation for the current recommendations and what information was not
included in developing that foundation and why.
2. Current format may not support nor ensure the competence of the findings (there is little to no
information about the process the EFSAB used to arrive at the current recommendations nor
how the EFSAB evaluated their choices for recommendations and the selection of the current
recommendations.
3. Where the recommendations are described, provide citations and/or links to the literature –
particularly peer-reviewed materials.
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4. Link the report in general to materials located on the Water.org website for further explanation
of the description in the report or to provide a basis for how the EFSAB chose to move forward
with its investigations.
5. Increase the level of clarity around the technical information including reducing the use of
technical jargon or explaining it in the report. Increase the readability of the report and therefore
the reader’s ability to understand the charge of the EFSAB, the path the EFSAB took to
address the charge, and the how, what, and why of deliverables chosen by the EFSAB.
6. Include a glossary to the report.
7. Other discussion points:
a. Limit to the # of pages
b. Rationale and assumptions included- determine what is enough
c. Drafting process – occur using writing teams
d. Edit process – a team of EFSAB members and external reviewer
VI. Presentation:
Concepts
and
Principles
Regarding
Ecological
Responses
to
Flows
and
Principles
Facilitator: Mary Lou Addor
The EFSAB had been asked to review the section of the DRAFT 3 Report titled, “Flow Regimes to
Maintain Ecological Integrity” (pgs.12-14; this section also referenced a portion of the July Meeting
Summary, pgs 74-78). Presented on pages 12-14, were concepts regarding ecological responses to
flows and principals for maintaining ecological integrity of freshwaters in North Carolina. These
concepts were derived from a list Tom Cuffney presented at the July meeting, titled: Ecological
Responses to Flows.
The current list of concepts is divided into five main categories in the Report:
1. Stream Ecology
2. Many studies that change in flow results in impact to aquatic and riparian biota
3. We have few tools that directly assess the biological effects
4. There is uncertainty in the science and the models, so we need to be risk adverse in
recommendations
5. Adaptive Management
If the EFSAB considers these principles and/or criteria, they may guide decision-making toward
recommendations for ecological flows for the remainder of the afternoon. How would the board like to
proceed?
During a discussion, several members of the board expressed concern about taking time to review and
develop an agreement about the list versus spending time directly developing recommendations that
would naturally offer context for the discussion. For the most part, members were comfortable with the
concepts listed on pages 12-14.
Comment: My concern with using our time to review this list of concepts is we do not know if any or all
of these listed on pages 12-14 will be pertinent in the decision-making process for the flow
recommendation. So, there may be a lot of these that are true statements though they may not drive a
direction toward recommendations. My preference would be to develop recommendations and then
discuss and describe the fundamental principles.
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Comment: In the main, I think these concepts are fine. I can pick out several of them that I have
questions about; some I believe are overstatements. I’d prefer to develop the recommendations and
then come back to these concepts if we need them.
Members of the EFSAB discussed their general agreement with the concepts regarding ecological
responses to flows and principles for maintaining ecological integrity of freshwaters in North Carolina.
These statements may later serve to as part of the supporting documentation for the recommendations
with additional clarity and rationale.
The decision was made to use the remaining meeting time to discuss and develop recommendations
for ecological flows.
[Following the Aug 20 meeting, Tom Gerow provided his perspective on pages 12-14]:
SECTION 1:
I could see all of these statements as "Findings", maybe with statement (e) being a Guiding
Principle.
SECTION 2:
The initial statement "Many studies show that changes in flow...." could itself be a Finding.
Findings: Items a,b,d.
Item (c) could be a Guiding Principle.
Item (d), the statements that starts with "Streams must have access to floodplains......" could be a
Recommendation.
Item (f) could either be a Finding or Guiding Principle.
SECTION 3:
I see all items as Findings. (items a through d).
SECTION 4:
I see all of these items as Recommendations (items a through g).
SECTION 5:
I could see both items as a Guiding Principle.
Alternatively, I could also see item (a) as a Recommendation.
Proposed definitions for terms:
A "Guiding Principle" should explain:
1) How to approach this task; 2) Assumptions that are being made; and 3) What this report is.... and
what this report is not.
A "Finding" equals a statement that says:
1) Our observations are __________.: 2) The literature review revealed _____________.3) Evidence
and data indicate or leads us to conclude ____________.
A "Recommendation" should:
1) Be a direct, actionable statement (either a tangible or intangible); 2) Include methods on how to
measure its progress, success, or failure.
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VII. EFSAB Report Writing Process – Establishment of Writing Teams
Facilitator: Mary Lou Addor
Toward the end of the August 21 meeting, writing teams were established to expand/revise Draft 3 of
the EFSAB report (Aug 16, 2013), in preparation of the Sept 24 and 25 meeting. The main goals are:
1. Provide a rationale for each recommendation developed by Sept 6 (anywhere from 1-3
pages)
2. Ensure the completeness of the document as best as possible. Lou will combine any iteration
into one document with support from Chris and Jamie.
3. Distribute Draft 4 by Sept 10 to the EFSAB listserv so that all members can begin to identify
gaps, areas where they are uncomfortable and why, raise questions, propose alternative
language and additional edits, including how to increase the readability of the report.
4. Receive comments/questions/alternative language/proposals from all EFSAB members by Sept
18 (request earlier return of comments by members working in tandem with their
alternates)
5. Provide marked up copy of Draft 4 with all comments to the EFSAB by Sept 23 (earlier if
possible)
6. Proposal: set aside 2 hours onsite (Sept 25) to make changes to the report moving the EFSAB
closer to one complete report.
The writing teams are:
1. Characterization Recommendation- Chris Goudreau and Linda Diebolt
2. EFlows Recommendation 1 - Statewide approach -Thomas Cuffney and Tom Thompson
3. EFlows Recommendation 2- Headwaters approach - Judy Ratcliffe and Jeff Hinshaw
4. Coastal Plain Strategy - Bob Christian and Linda Diebolt
5. Glossary - Fred Tarver
6. Reorganization of Report – Jamie Robinson and Chris Goudreau
Recommendations:
1. Characterization Recommendation: Chris and Linda with Tom Cuffney (Tom has an interest in
this section and will do what he can to review). This includes any pertinent rationale/assumptions,
citations and references to justify what is being proposed in the characterization recommendation.
Writing teams are asked to include other research and literature that was reviewed and rejected to
arrive at the characterization recommendation.
2. Eflow Recommendation 1: Tom Cuffney and Tom Thompson will work on this section. This
includes any pertinent rationale/assumptions, citations and references to justify what is being proposed
in recommendation 1. Jennifer Phelan is sending a section of the RTI report that will assist in
supporting the choice of 5%, 10% and the 15% thresholds early Sept. Writing teams are asked to
include other research and literature that was reviewed and rejected to arrive at recommendation 1.
Statewide approach using simultaneously two tools:
§ In the basinwide hydrologic models, use 80-90% flow-by as the ecological flow.
§ If the basinwide hydrologic models indicate that there is insufficient water available to meet all
needs, essential water uses and ecological flows, then further review is recommended.
§ The Eco-deficit tool should be used to determine the current and future modeled biological
condition of locations in the basinwide hydrologic models.
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§ DENR should evaluate the change in current and future biological condition as a decision
criterion. A 5-10% change in biological condition is suggested as a threshold for further review
by DENR. [section requires further discussion/review by EFSAB to determine if all members
can live with/support this statement].”
3. Eflow Recommendation 2: Judy & Jeff (Judy may look to Mark, and Sarah to assist). This includes
any pertinent rationale/assumptions, citations and references to justify what is being proposed in
recommendation 2. Writing teams are asked to include other research and literature that was reviewed
and rejected to arrive at recommendation 2.
"Headwater Streams – There is limited biological and hydrologic data in headwater streams within
North Carolina. These streams have a higher vulnerability to disturbance, and the broader
statewide approach may not adequately reflect the potential for impact to ecological integrity.
Therefore, DENR should identify the subset of headwater streams to receive alternative analysis.
(Note for further explaining- examples of vulnerability, how and in what way. Less water to start
could be converted to intermittent)."
4. Coastal Plain Strategy: Linda Diebolt has suggestions for the Coastal section and would like to
work with you, Bob, to address that section. This would include the changes that resulted from the Aug
21 discussion and any pertinent rationale/assumptions and citations and references to justify what is
being proposed in the coastal strategy. Writing teams are asked to include other research and
literature that was reviewed and rejected to arrive as this strategy.
VIII. Discussion
on
Characterization
Facilitator: Mary Lou Addor
A draft section on characterization was completed by a small writing committee composed of Mark
Cantrell, Linda Diebolt, Jamie Robinson, and Chris Goudreau and presented to the EFSAB for
discussion as part of the revised report that was sent to them before the meeting, and provided as a
handout. The key points of discussion follow.
¥ What was the value of discussing the public ownership of land in the mountains?
o Intent was to describe the vegetative state of the watersheds and got into public lands
managed with vegetation as a goal.
o Better to describe the land cover rather than ownership.
o We had said we might reference basinwide plans or other documents that include more
details, those included land use and ownership within them.
o Could add “sparsely developed” to flesh out why public ownership is relevant
¥ Unsure of the relevance of characterization in the way it’s currently reflected in this draft of report,
given that EFSAB did not focus upon it in this fashion.
¥ The distinction between the piedmont, mountains, coastal plain may not add value for
characterization.
¥ If we’re going to put these statements in, they need to add something to the discussion of our
conclusions. For example forested cover is too broad, x% forested is better.
¥ Other reports spent considerable pages on characterizing watersheds and streams. We should
either say we didn’t get around to it, or we improve upon what we have.
¥ Current draft attempts to address characterization in terms of hydrology, biology, geomorphology,
and water quality, connectivity.
¥ Make our recommendations and then back up and see what we need to include based on that. A
lot of those answers may come after we have recommendations to provide justification. (Many
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comments of this type were made)
o If recommendations are classification dependent, than there should be more detail there to
support the recommendation.
o It’s possible the flow recommendation will be purely hydrologically based, in which case we
won’t need to characterize the ecology.
o If we go with something USGS/RTI proposed then it makes a difference and we need to get
something in there.
o We need in include ecological integrity and characterization as basis for making ecological
flow recommendations.
¥ RTI and USGS did a lot of work on classification (as a means for characterization). Many various
methods were tried that need to be reflected in the document, but it will be hard to include until the
RTI report is written.
¥ The legislation calls for EFSAB to characterize ecology in the different river basins, which we tried
to do through classification.
o If we don’t have a recommendation, we need to be clear about how we’re addressing the
charge in the legislation.
¥ The current level of detail is enough, though the content may need to change.
¥ If an EFSAB member has a suggestion for what to include, they should write it down (edit the
document)
¥ DWR staff characterizes the basins when doing basin plans, so we may not need to do it but rather
say that DWR already does this, and we are focusing on the more critical piece, ecological flows.
¥ Suggest a different way to characterize ecology, regardless of the recommendations, that can be
done by talking about high flows important for this reason, base flows are important for this reason,
overbank flows are necessary because of x, basically the relationships between different flow
components and ecology. That stands on its own and we could do that now in a page or two
rather than wait until the last minute. We could find this information in other documents: Texas,
Alberta, Susquehanna reports. (Agreement expressed from another)
¥ It needs to come out of findings and into a preface section. Its not a finding, but rather it sets stage
for characterizing ecology
Based on the group’s interest in focusing on the ecological flows recommendation, they set
characterization aside and moved on.
Action item: Chris Goudreau and Linda Diebolt offered to work on the characterization section
outside of the meeting.
IX. Presentation:
Approaches
for
Setting
Protection
Standards
Presenter: Chris Goudreau
This power point presentation is available here
As a lead in to the discussion around developing the flow recommendations, Chris Goudreau reviewed
the general approaches that can be taken for flow recommendations as defined by Richter et al.
(2011). The three approaches defined by Richter include:
1. Minimum flow threshold-- which might be a single value (e.g., 7Q10) or be seasonally adjusted
(e.g., Tennant, South Carolina);
2. Statistically-based standard—this Board has not discussed this type of approach much, but it
attempts to mimic as much as possible all the components of a flow regime, such as:
¥ Critical low, low, high flow pulses, small floods, high floods
¥ Wet, normal, dry years
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¥ For each, includes magnitude, duration, frequency, season
¥ Tied to ecologically significant events
o E.g., spawning, floodplain rejuvenation, fry/juvenile growth, migration, sediment
movement, channel maintenance
3. Percent of flow standard (e.g., Alberta)
Chris then identified which of those approaches were employed by the various trial balloons that have
been presented to the EFSAB. The RTI/USGS (ad-hoc) approach does not fit into Richter’s scheme.
Chris put this together to assess the various trial balloons in light of the principles that the EFSAB
loosely agreed upon. Chris showed some graphs depicting what these would look like. He then
showed how the various trial balloons could be applied to the various stream sizes used in the
recommendations developed in July.
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X. Discussion:
Continued
July
Discussions
on
Development
of
Flow
Recommendations
Facilitator: Nancy Sharpless
The Board then looked at the tentative recommendations that had been developed in July, which were
based on stream size:
¥ Small stream protection draft recommendation in July
o Make sure that whatever methods are used in the recommendations for wadeable
streams address the issue of extra protection for small streams.
o Define small stream.
o Clarify what site-specific evaluation means.
¥ Large rivers draft recommendation in July
o Define large rivers
o Use a flow-by approach
o Use some type of floor/cut-off/ environmental base flow (EBF)
o Address cumulative effects
¥ Wadeable streams draft recommendation in July
o Use a flow by approach
o Apply EBF/South Carolina (SC)-modified, for when a flag goes up
o Characterize difference between wadeable, small catchments, large rivers
o Address cumulative effects
o Use the RTI/USGS tool for assessing biological responses to altered flows
¥ With additional recommendations developed in July
o Endangered/threatened species
o Adaptive management
o Site specific follow up from DWR
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The facilitator asked the Board if this was still the approach they wanted to take since several people
were not present when these recommendations were developed and given the RTI/USGS presentation
this morning.
Comments included:
¥ What would catchment size be for small streams? <100km?
¥ Is a flow-by based on instantaneous flow, daily, monthly…needs definition
¥ With the new RTI/USGS tool, we could go with a minimum threshold; it is not my choice, but
with what Jen presented, you wouldn’t ask how much is coming out; you’re asking where is this
node on the linear relationship, then calculate to see if you cross the threshold.
¥ The RTI/USGS tool is a method for assessing the impact of any method you choose.
Once you make a decision in how you handle the flow, then you can measure the
ecodeficit and determine a priori what the risk is. It’s not a method for setting eco-flow
but for evaluating any decision you make. That should be clear.
¥ I thought it would preclude the need for establishing e-flows if you put in the water here now
and for 2050.
¥ Those numbers were arbitrary to start a discussion. The numbers have to be set by
somebody.
¥ It is a measuring tool.
¥ Threshold approaches do not address the natural flow paradigm.
¥ Fransen looked at it as you not only need to protect an eco-flow but essential uses. Either e-
flow is a flat line or people are cut off from using water. This is different from a % flow
approach, where both portions are getting something all the time; it is reduced but not flat line.
¥ If you do a % flow and a threshold, you will still come up against that (but for a short time). % of
flow without that you’d have natural flow extended down beyond the natural. That’s why
combine them.
¥ Stick with this classification of the streams, so we address the concerns that are size related.
That is the fundamental thing- we frame recommendations because size of stream will be an
important factor about how you maintain ecological integrity. Small streams are more
vulnerable. With large rivers we are making somewhat of a reach because the data are from
wadeable streams. I agree personally that the threshold approach alone is probably not
protective enough of ecological integrity. We have to decide what that number is.
¥ Acknowledge that small streams/headwaters are vulnerable and document why.
¥ We have the same approach, with 3 sizes, with different levels of protection. With larger
streams we probably need more data.
¥ Headwaters, you’re talking about 90% of impounded farm pounds in the state are headwaters.
¥ We’ve kicked around that we can make the recommendation of importance of protecting
headwater streams; science suggests they are the most vulnerable and maybe leave it like
that. I’m not sure I would say no touch, but recognize vulnerability.
¥ If there is science that says a withdrawal of 100 mgd from most headwater streams would have
a significant ecological impact, we should say that.
¥ That’s fine but if we then say that it shouldn’t be allowed…
¥ We can say we think if you withdraw 100k mgd then you violate eco integrity, but then not
recommend policy of not allowing that.
¥ It’s DENRs policy call to determine
¥ What is a recommendation vs. just a statement? I think that is just a statement, not a
recommendation.
¥ We recommend that DWR take that into consideration. We’re presenting all this info and we
hope you take it into consideration as you make policy
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¥ It is not realistic to think a lot of straws will go into the small streams. Its really really important
that we make decisions about the likely locations of withdrawals.
¥ My point was the policy statement of saying hands off of headwaters, where already people are
using them for impoundments. The straws are often already in place.
¥ My concern about the RTI/USGS tool is the original fit of data. The data was not a clear
straight line, but they made it fit.
¥ The larger the stream, the more permitted withdrawals, the smaller, then the more unpermitted
withdrawals…. it behooves us to be more conservative in the headwaters because there are a
lot of unpermitted uses.
¥ We could look at what permitted withdrawals are on what size streams.
¥ OASIS does not include withdrawals less than 100,000gpd. Less than 100,000 will be
aggregated.
¥ There are two ways to get at headwater streams: 1) percent flow-by, which could be different
from other sizes; or 2) use some flow-by and if using USGS/RTI, have a different allowable
percent change in the biological condition. You could combine the 2.
At this point the Board developed 2 draft recommendations using a statewide approach to e-
flow with a different criterion for headwaters:
Recommendation 1: Statewide approach using simultaneously two tools:
1. Use [x percentage] of flow-by as the flow regime
2. Use eco-deficit tool to identify the effect on the ecological integrity.
a. Combine eco-deficit tool with the criteria to be used as a flagging tool
Recommendation 2: Use the two tools with different criteria for headwaters.
This draft recommendation received full support with the understanding that a list of statements
(caveats) would need to be developed to include in the report. These recommendations were
subsequently refined further the next day.
The EFSAB developed a list of questions to be addressed and a proposed list of statements to
accompany the recommendations in the report [some of these were added on 8/21; the issues in italics
are from 8/20]:
Questions to address:
¥ % for flow-by
¥ Develop criteria for acceptable % change in biological condition
¥ Determine if including seasonal differences
¥ How often does it have to drop below for a flag to go up
¥ For eco-deficit, use fish or invertebrates?
¥ When using SIMBASE, does that change over time?
¥ What level of ecological integrity are the recommendations protecting?
¥ Advise DWR on how to assess condition of stream?
Statements to include in report:
¥ Limitations of data used to develop the eco-deficit tool
o This is already in the report
o When will the RTI/USGS report be published?
¥ PHabSIM could be used when flag is raised.
¥ Issue of it is all modeling—DWR is working in models. Everything is modeled. The
assumptions are based on the models
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¥ It should say it is calculated on a daily time-step
¥ What time step to use in flow-by
¥ How is flow-by calculated
¥ What is the index flow for calculating % flow by
¥ Define terms (%flow-by, eco-deficit)
¥ Include a description of where the high end of the flow-by range would be used.
¥ As data is collected and knowledge develops using the eco-deficit approach, eco-deficit
knowledge might inform changing the % flow-by
¥ Describe where the range of % biological change comes from and authors provide examples of
how it works.
¥ For headwaters, there may not be a node in OASIS. WaterFALL is probably the only tool
available, and it did not correspond well with OASIS. You may not be able to use two tools in
the headwaters because there may not be a node there.
¥ Explain that the model that was done was based on using unregulated flow and based on that
we pick these numbers. Put in a statement that you look at the cumulative effect of
withdrawals and take that into account.
¥ Justification of the flow-by range.
¥ We can point to other places, and we can add qualitative descriptions of reasons of where
you’d want the flag to be triggered earlier, for example less resilient lands, or where you have
cumulative effects. If we were talking about a regulatory program I’d articulate it differently, but
if we’re talking about when do you want to take a closer look, I think it is more appropriate for
certain streams that may be more vulnerable, to have a higher percentage to trigger a closer
look.
¥ In the Richter paper Table 2, FL, MI, ME, EU, those percentages are 80-92.5% flow-by. FL is
based on its own information, 80-92%; MI is 85-94%; ME is 90%.
¥ Look at the cumulative effect of withdrawals and take that into account
¥ When we’re saying to maintain ecological integrity, we’ll at some point define what it is.
Another potential recommendation was proposed: The current SIMBASE2013 should be used
as the prevailing condition from now forward.
August 21, 2013
I. August
21
Meeting
Orientation
Members, alternates and guests of the Ecological Board Science Advisory Board introduced
themselves and their affiliations. The facilitation team also introduced themselves. Everyone was
reminded to sign-in who attended the meeting.
The facilitator reviewed the revised agenda. The meeting would start with a discussion of headwater
streams, followed by a discussion about the framework of recommendations in Coastal Streams and
Rivers, then moving into spending the majority of the day continuing to develop flow recommendations.
The day would end with developing writing subcommittees and developing the agenda for September.
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II. Continued
Discussion
of
Stream
Size
Classification
and
Headwater
Streams
Facilitator: Christy Perrin
On Aug 21, the EFSAB picked up from where they left off Tuesday in discussing stream size
classification. The members were asked to review the latest version of the SALCC DA Distribution (a
corrected version was reviewed on Aug 21 that separated the headwaters and the creeks (previously
combined) and corrected minor miscalculations). Based on a random set of 900 points, the numbers
of the very small basins – less than 3.6 square kilometers – are very under-represented in the DWQ
data. Really small streams tend to become intermittent and thus more difficult to track and to assess
water quality in those systems. These systems require a different set of standards. With respect to
the headwaters, using the RTI/USGS regressions, this reinforces the notion that smaller and smaller
headwater streams are less applicable because these systems become intermittent, and are totally
different. This supports the argument from yesterday to handle these very small headwater streams
differently.
Do headwaters have complete guild assemblages?
The EFSAB discussed the biological assemblages of these very small streams. Tom made the point
that these streams would have EPT, but of a different kind. Vann offered that he consistently found fish
in ? size streams.
Is it more appropriate to lump into larger group or keep separate and note the lack of data?
(preference is not to lump)
What is the interpretation? Is it more appropriate to lump together in the next larger group? Or more
appropriate to retain that separate group and simply state, we don’t have the information. Or is there
even enough information to propose anything specific other than if we have literature that suggests the
need for treating them separately -what’s the best approach?
If we’re trying to retain these classes in some way, relative to the RTI data, do we lump them with the
next larger group or separate with a caveat that, within this group there is information in some areas
and in others there is not information.
There are data for the headwaters but not for the intermittent streams
We do have information for headwater perennial streams; we don’t have information for the intermittent
streams since the state does not monitor them. We could apply a different criteria for intermittent from
perennial headwater streams (and may need to set a different criteria flowby).
Class
DA
km2 Inverts Fish Rand
Headwaters <=10 85 255 509
Creeks <100 616 878 270
Small Rivers <518 154 411 67
Medium Tributary Rivers <2590 3 133 36
Medium Mainstem Rivers <10000 0 43 12
Large Rivers <25000 0 17 7
Great Rivers >25000 0 0 0
858 1737 901
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Percentage of Sites
Class
DA
km2 Inverts Fish Rand Biol Rand
Headwaters <=10 9.9 14.7 56.5 13.1 56.5
Creeks <100 71.8 50.5 30.0 57.6 30.0
Small Rivers <518 17.9 23.7 7.4 21.8 7.4
Medium Tributary Rivers <2590 0.3 7.7 4.0 5.2 4.0
Medium Mainstem Rivers <10000 0.0 2.5 1.3 1.7 1.3
Large Rivers <25000 0 1 1 1 1
Great Rivers >25000 0 0 0 0 0
100 100 100 100 100
If applying different criteria, state in the report for headwaters perennials that everything
sampled by DWR/DWQ has record of evidence.
Someone mentioned that the headwaters and creeks are set at 10 square kilometers that one gets
more biological samples with random for creeks and a lot fewer biological samples of random for
headwaters. If one slides that break 10 kilometers down a little bit, one might pick up some of the
larger headwaters. This would provide better representation for the creek. And thus reduce the
number of headwater streams to be treated differently. May even consider setting aside non-perennial
streams. The older USGS report by Geise and Mason (USGS report) had relationships by basin on
what drainage area produced a 0 flow stream during a year [or something like this]. They had a
relationship of how to figure out what size stream in each basin in the state was from 0 flow stream.
Perhaps this would be a way to draw the line between intermittent and perennial streams and which
ones that might or might not be covered by hydrologic area and not by river basins? OASIS
aggregates small withdrawals criteria; WaterFALL does better in small catchments.
What does vulnerability mean? How best to convey it? What is the reference condition?
A discussion about vulnerability ensued. The board may not have much information at this time to
address the extremes – except to convey vulnerability. Perhaps focus on small river, medium
tributaries where there is enough information, and for the headwaters say they are extremely
vulnerable.
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In what way are these vulnerable? What are they vulnerable to? Are they vulnerable to it at some
percentage flow-by reduction, therefore making them from perennial to intermediate? Is that the idea
of their vulnerability? Or are they biologically more vulnerable than a larger stream? What do we
know about that?
Vulnerability can be considered when these streams seasonally reached a 0 flow; even though there’s
volume, there’s not protectable flow. Or in some cases they may be drying out completely, seasonally,
or experience extreme events in their hydrologic cycle. And even in the natural condition. For
example: upper Tar (Sheldon Creek) over the past 3 or 4 years, every summer you go up there and
there’s hundreds and hundreds of dead mussels, because there’s no flow in creek and thus is not a
good candidate for a withdrawal proposal. Given the 5 years of drought, the creeks have dried out
completely and turned into giant sidewalks. There are ecological impacts when there is no water at all.
How to test/support vulnerability?
How do we know that? Can you test the difference between something that is dry for 0 times, versus 5
days a year, versus a month a year? Is this due to a natural cycle, or is there a withdrawal that’s
causing that?
Think back to the Alberta and the environmental base flows. If you add a withdrawal factor,
conceptually this will extend the period of time extreme values are being experienced. This can be
demonstrated on the hydrograph. That’s the concept that they’re looking at in Alberta and something
we can consider for all streams.
Extremes that are beneficial; extremes that are not beneficial – what is the reference condition?
Need referenced information. The risk is that on the flip side, we may try to justify and make the point
that extremes in terms of flooding and over bank flow are beneficial. An extreme in one case is a
negative, and an extreme in another case is a positive, like flooding.
Someone else mentioned that all flooding is not created equal. There are very unnatural flooding
scenarios in which streams are inundated for a much longer period of time or in seasons when it’s not
appropriate for them to be inundated. That causes a significant shift in the ecology. It is happening this
year and it happened last year.
But is this unnatural? It is happening because of the change in the precipitation pattern. Whatever
goes into the report, it needs to be referenced and justified.
One possible way of talking about exception for headwaters may be a different kind of metric. Not sure
how this could work in OASIS, because there are not many nodes in these areas. But given a basin
with a node in this kind of situation, if a natural scenario changes the stream from a perennial stream
to an intermittent stream then this is pretty extreme change.
What is being explored is the use of Tom’s numbers. The smallest class is not going to change based
on class boundaries here. So those 10 square kilometer headwater streams, if only 25% of them
essentially have biological data in them, and the rest of them don’t – either because they’re intermittent
or they’re just too small to sample, in terms of these protocols. Thus a large portion of those is already
probably intermittent. So the question is, does that push the remaining bunch of 25% or whatever from
perennial to intermittent? That is a big change, but it’s another way of dealing with protection to
headwaters. Still will have criteria of changes in the eco-deficit numbers.
Definition of Intermittent Flow
Intermittent means you have 1 day of zero flow. Whose definition is this? The term ‘intermittent’ is used
in different contexts by different people. In the board’s previous work of the hydrologic classification
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piece, there was the use of a term, intermittent. That pushed away to whether there was any
measurable flow. Though (to me) that’s not the definition of intermittent; there is the need to look at the
long-term pattern of that stream. Biological assemblage should define intermittent There is a need to
settle on a definition of intermittent.
Do we need to mention headwaters in smallest systems?
Is there a need for this level of concern about what to say about headwaters in the smallest systems,
since they are almost out by the bounds, if it’s not completely out of the bounds by what is currently
tracked by DWR? Because at 100 kilometers, is there going to be 100,000 gallons per day
withdrawal? [Some said – the point is, it could be].
Do you all want to spend alot of time trying to refine a specific recommendation in the absence of this
information? On the other hand, if one causes a stream to be de-watered that is not normally de-
watered, it’s a safe statement to state that there likely will be an impact on the ecology of the stream.
Therefore these streams need a high level of protection in the absence of that kind of information. But
the reality is, it’s unlikely these are going to be capable of supporting large amounts of withdrawal, or
permanent withdrawals anyway. Or, they’d be willing to issue a permit for withdrawal. The question is:
do we lump the remaining part of these- the perennial parts of the headwater streams in with the larger
category? Or do we leave them separately? Do we lump them together with the creeks, and state that
everything from whatever the size was – less than 75 square kilometers should also be treated
similarly? Or do they need something separate?
Ecodeficit tool to investigate the potential increase in small streams
On Aug 20, when RTI presented, I was struck by the comparison of the Eno River and the Neuse, and
what percentage, what amount was being withdrawn before it shifted. If the board had that tool,
perhaps the board could see how much of a withdrawal is observed for these small headwater streams
and the change involved. If that happens, and dependent on where it occurs, that might capture how to
examine the headwaters.
Considering the recommendation from Tuesday regarding statewide percentage of flow-by and what
Jeff is talking about, one way to deal with this is to use that approach for nodes and drainage areas
with greater than 10 square kilometers. Then, if there’s a node in a drainage area with less than 10
square kilometers, slide those out. This would provide more detail than the analysis needs because
there’s not going to many of those to start with. Right up there where there are nodes in drainage
areas smaller than 10 square kilometers up there.
Question: do we have OASIS models, summaries that show all the nodes and their drainage areas of
the ones that are done so far?
There are nodes in models where there are existing gages.
Think there is a lot of research that will support the vulnerability of small streams for water withdrawal.
I’m certain that there is information in the literature we have reviewed that describes the vulnerability of
small systems.
Beginning to Generate a Recommendation for Headwaters
The morning discussion began to generate a recommendation for headwaters and how smaller creeks
are handled, including a statement of vulnerability. One is a boundary condition; that there is
uncertainty about hydrology data and modeling in headwater streams. Specifically, there are no gages
to test, calibrate the model. Second, is the high likelihood of greater vulnerability to the streams if
withdrawals happen. Therefore, if there were a proposed withdrawal, specifically less than 10 square
kilometer drainages, then this would flag DWR to follow up and determine how to proceed.
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Can we go greater than 10 to 100 square kilometers? Thinking of Virginia and the confidence we had
in their model would give the board the ability to make a numerical recommendation. Less than 10
kilometers, we’re not going to make a numerical recommendation. [Recommend to avoid getting
bogged down in debating the confidence of the probability of 10 versus 12 versus 20, but establishing
kind of threshold here].
In the OASIS model when it first was started, the smallest drainage area in the model at that point was
about 100 square miles or 100 square kilometers. That’s big; there are two things going on in here.
One is the restrictions on the OASIS, and the other is the restriction on the water supply here, which
would be related to the availability of calibration gages. Which may be much smaller than 100. But
there are kind of two different things going on here. One is how to evaluate the model – the RTI,
USGS model – that is depending on what you can use to calibrate it. And the other is if you plot it
using the OASIS, what are the restrictions on that? And they’re two separate things. And I think that
maybe we need to leave that up to DWR to determine what they need to address it, based I think on
what we decide.
There are two ways to get at headwater streams: 1) percent flow-by, which could be different from
other sizes; or 2) use some flow-by and if using USGS/RTI, have a different allowable percent change
in the biological condition. You could combine the two.
Numeric Thresholds: Narrative, Range or A Numeric Number
A member put forth the suggestion to avoid establishing numeric thresholds and substitute narrative
descriptions of headwaters and creeks, or small streams. Consider combining statements 1 and 2,
without a numerical threshold given without providing some security in those numbers.
1. One is perennial streams where the action is likely to make them intermittent. This would be one flag
to address as the categories change from perennial to intermittent.
2. Second is to consider the headwater streams now. That if it’s a first order stream, or second order
stream, the flag goes up. Thus, do not about whether that’s 12 acres or 20 acres.
The board is struggling with the number of intersect and continuance; with the smaller the drainage
area, the greater the vulnerability. But then we talk about the continuum of how much a withdrawal of
percent flow-by. These are intersecting continuums and have different numbers depending on how
these areas are taken from minor to severe. As a Science Advisory Board, my proposal is to offer
advice but not necessarily numerical recommendations. In our report, let’s discuss relative smaller
systems without quantifying them. If somebody was to take out a gallon in a small system, we’re not
going to worry too much about that. But if they want to take out 80% of the flow and divert for use on a
trout farm that might not be a good idea. In fact, it might not be a good idea to take out 20% of the
water for trout farms in part of the systems. We want to offer a high degree of caution for those kinds
of planning and migrations. We could go from a vertical analysis to a second or third or where moving
site specific. I think if we try to go down the path of doing that type of quantitative definitions, as a
scientific advisory board we should be highly confident in what our recommendations are. And I don’t
believe we are. That’s why I’m suggesting some sort of language advice rather than a quantitative
debate. Numerical trigger point either has good scientific confidence based on real information, or we
have to insert our own value judgments in establishing the trigger point. It’s trying to avoid those value
judgments, which I think are best done by commissions and divisions. Even though we have spent
three years learning this new language of ecological flow related terminology and issues, we likely
more knowledgeable than most other science board who could provide value judgment bodies. Is that
our job? I think our job is to find scientific advice and not establish uncertain thresholds. We do not
want to get bogged down here into philosophical difference because we’re way too close in agreement
here.
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Another said, I understand the problem with hard thresholds. Though not clear how we can substitute
narrative descriptions of headwaters and creeks, or small streams. Maybe this means we consider a
range of numbers or better criteria, by which we can define vulnerability.
Perhaps we don’t have to put a number limit to the point of excluding any particular size of headwater
stream. If we say small headwater streams, and then we can give examples, or use RTI’s limits of
utilization or the data that RTI has available for their models. Provide justification of what they found,
that they had this information for calibrating their model below a certain size, or above a certain size.
Those would be descriptors, but then leave to DWR to determine specifically where that line pops up.
Another option is that at some given known condition, x, a flag is raised. If we don’t, then our
description of that condition, x that triggers the flag is arbitrary and capricious, or too vague for
planning purposes. But our recommendation, putting aside a hard size limit, is for a particular action.
That particular action is the need for more information – such as a site-specific evaluation.
If you’re going to propose a node into small drainage basins - that is a recommendation for a specific
action. That’s different than describing a continuum of vulnerability through different sized drainage
basins. I’m hesitant to go down a road where we are not recommending and instead are performing
primarily a scientific descriptive function rather than having actual recommendations on where
additional information is needed. I’m not at all advocating that our recommendations should disallow a
withdrawal or prohibit or restrict. I’m not interested in any of that language. But I am interested in
having clear demarcations where we think additional information is needed. Where the basic flow-by
standard that whatever percent it could be agreed on is appropriate for DWR’s use as the flag. Those
are recommendations for trigger points and it is challenging to have a trigger point that is tied to the art
of hydrology, rather than simply making a couple of them.
May want to consider 4 options on what to do in areas where there is limited gage data, limited OASIS
information:
1. Narrative description
2. Narrative description that includes hard numbers or range of numbers.
3. Skip narrative and put in a range.
4. Develop criteria around vulnerability that may include a stream size dependent
Other considerations:
Do exact same thing without #s – options for recommendations and hard #s where limited
gages (OASIS data)
a. name the description with a range of #s
b. define vulnerability – continuous vulnerability as size increases
c. offer advice not numerical recommendations about relative vulnerability
Alternatives to an area
a. actions from perennial to intermittent raises flag
b. 1st or 2nd order stream raises flag (not popular)
c. Condition X triggers a flag if our recommendation doesn’t allow a decision-flow
chart….indicate where additional information is needed.
Chris, Judy, and Jeff agreed to develop a recommendation for Headwaters that the group could review
and discuss in the afternoon.
III. Discussion:
Framework
for
Recommendations
in
Coastal
Streams
and
Rivers
Coastal
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After a brief review of the framework of recommendations that Bob Christian presented to the Board on
August 20, the facilitator solicited comments and suggestions from the Board for Bob in drafting this
section of the EFSAB report. Those comments and suggestions included:
• Is the idea that you recommend all 4 approaches and that there would be some hierarchy for
which approach to apply to a given type of stream?
o I would leave these as parallel tracks. Where the statewide approach can comfortably
be extended, that would be the first order approach. But then I think the next best step
is to look at the effects on anadromous fish and other important species and develop
the approaches from the biological point of view. Salinity would be almost a fallback. I
see overbank flow as an add-on; in certain places, the overbank flow is an additional
concern, not an alternate concern
• It sounds like you are saying that the EFSAB is not in a position to provide recommendations
for the coastal areas, but here is a list of options and advice for making a path forward.
• The recommendation is to develop this framework.
• The gradient cut-offs are somewhat arbitrary, based on professional judgment.
• One of the challenges we are dealing with here is that slope and velocity are not the same;
velocity is incredibly important. It is really the velocity that relates to ecological condition. The
gradients may or may not be indicative of velocity.
o In some ways, though, it is the depth of the stream that determines the amount of
habitat, and in the coastal plain, that is disconnected from the discharge.
• In terms of practical application, if you take it at face value, everything in black, red or turquoise
might fit into the rest of the recommendations.
o Maybe the black and the inland red. I just don't know about the turquoise areas. It may
be that when we look at how to extend the statewide recommendations, the distinction
between inner and outer coastal plain may become a more critical factor.
o Where you have the turquoise areas that are not contiguous with the coastline, they
may be low-head dams or things like that.
• I'm very supportive of dealing with our coastal areas with if/then statements. If DWR wants to
pursue scientific understanding of how to evaluate ecological flows in the coastal plain, then
our advice would be to go through these options. I'm not comfortable with going forward with
those as recommendations; I distinguish between advice and recommendations because I
don't think we know enough about how to get to an ecological flow in the coastal plain to make
recommendations, but I am very comfortable with what Bob has presented and the attributes
he has talked about. If DENR is interested in developing that, we have given them ways to
move forward with it. Frankly, I think it would be wonderful research to pursue.
• I think this subcommittee has done the absolute best job possible on this.
o In such a short time.
o Highly commendable.
• We should decide the link between the EFSAB report and this subcommittee's report.
• I would advocate an integrated whole for the EFSAB report as much as possible. I think a
thorough summary of he coastal work should be included in the report because the coastal
subcommittee's work has been so good, and it mirrors the work that the whole board has done.
I think of it as an integrated whole and encourage us to have a comprehensive report from the
Board at the end of the day.
• The committee's 3-page report or the 12-page report?
• That goes back to whether we have a 10-page EFSAB report with appendices or a longer
report, which we have not yet resolved.
• I think as much as possible, put the research needs into qualitative description of your if/then
statements. State for your 3 or 4 approaches, how the research needs bolster those. That
would help explain how/why this research is needed.
• When I look at the map of the four classes of streams and the cover slide that shows the
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OASIS model area, I think a lot of those that are piedmont, medium-slope are going to be
captured in the OASIS models. If that is the case, then those could automatically go into the
statewide approach. It's not really additional research but rather a next step: overlay those
and see what drops out already.
IV. Discussion:
Statewide
Flow
Recommendations
The facilitator invited the Board to look at the draft recommendations as they were at the end of 8/20
and the list of remaining questions to address. Comments included:
¥ On the third bullet [2a above in recommendation 1] of recommendation 1, what criteria? %
change criteria?
¥ It should be flow-by regime to maintain ecological integrity
¥ % of what flow? What is the index flow?
¥ Are there seasonal differences that might be applied?
¥ Use x% of flow-by calculated on a daily time step
o In Fred’s proposal, baseline hydrograph today is x, multiply it by .8, then works it
through the spreadsheet. People want to know how many days its over.
o Isn’t it averaged into a daily?
o The withdrawal amount is a seasonally or monthly adjusted value, but the number, even
if constant for a month, you want it contrasted vs. a daily number. The metric that goes
into an eco-flow is calculated daily.
o The flag goes up when violated once?
o Regardless, we’re not making that decision…I’m not convinced it needs to be done on a
daily time step. I think it is fine on a weekly time step.
o It would give you a different outcome, probably wouldn’t send up any flags.
o Calculate using a specific period of record?
o They generate a period of record that is used for the entire basin.
o It is different from how eco-deficit is calculated in the RTI work, which uses natural
vegetation; it needs to be specified.
o It is good to have two different approaches.
¥ Include a calculation of unregulated flow for comparison
o Publications that have proposed a % of flow-by use a reference point, index flow, on
which to base % flow. What we are talking about that index flow. Is it based on natural
flow, current condition, etc? The percent tool will be a % of that index
o Advise DWR to assess current alteration compared to unaltered.
¥ The time step is also factored in. We don’t necessarily need to specify that. It will need to be
decided by somebody.
¥ We need to define flow-by before I can agree on a recommendation.
o We could just Richter’s definition.
o What is currently used as the index flow? Period of record for a particular day?
o For PHabSIM it was .85 times every daily flow in the record—80 years x 365 flows x
.85.
o Richter paper didn’t have NC data set.
o His paper uses it as a presumptive standard. You could remove up to x % of the
ambient flow.
o The baseline condition as determined by Fransen? SIMBASE? SIMBASE is the
current condition using 80 years of record.
o For the purpose of calculating when to raise the flag, we need a point of reference.
You’re suggesting SIMBASE be used.
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o OASIS is based on historical record and assumes that history continues. Year 2050
projected flows take historical flows and bolt onto those the projected alterations. They
assume 1930- 2010 record of flow based on gauge data is the pattern that will continue
into the future but with projected withdrawals and discharges, and you can do %
increase or decrease based on climate change.
¥ The Board tentatively defined flow-by as: The percentage of ambient modeled daily flow that
remains in the stream. For modeling purposes this is calculated on a daily basis. [Need to
define somewhere how daily flow is reached].
¥ The Board opted to continue fleshing out recommendations and let writers define terms, then
address any concerns about that later.
The Board decided that the first decisions to be addressed should be 1) what the x is in x% flow-by;
and 2) biological impact.
The facilitator suggested that the Board start with the X% flow-by and start by narrowing in on a range
for that number. She pointed out that several of the trial balloons had suggested similar percentages.
Comments included:
The only ones in the trial balloons were 80 and 85%.
¥ Didn't TNC have 90%?
¥ It was 90-95%, but it was on a monthly, not a monthly time step...it was on a monthly statistic,
which is different from what we are talking about. It's hard for me to figure out.
¥ Wasn’t it mostly an average monthly average that would account for the seasonal issues?
¥ Let's use 80-85%.
¥ We're saying that % of flow by is going to be done in concert with knowledge of biological
deficit as well. We can use biological deficit to determine what that % would be.
¥ The eco-deficit tool is just a tool to measure the change in eco-deficit, but if somebody comes
up with what % change would raise a flag it could also raise a flag.
¥ So if you have a flow by of 80% and it gave you a 20% change in biology and we had flow-by of
85 % and it gave you 2% change in biology. That larger change gives you a bigger bang for
you buck and would inform your selection.
¥ But you would have to do it node by node by node, and I don't know if that is practicable. We
need to set our statewide flow-by and it can raise a flag, and at the same time we are going to
use the eco-deficit piece and that gives you a more precise numerical impact that you can
show how big a shift you are going to get. You might not get a flag at 80% but see a huge
change in the biology.
¥ What I hear is that you want two separate flagging mechanisms rather than one.
¥ I think the original intent of RTI was to use it as an evaluation too. You flag with an x% flow by
then you use the eco-deficit tool to evaluate how much change you get in the biology. But once
you get enough data down the road, you can also use that eco-deficit tool as another flagging
tool.
¥ So you're suggesting that your first order review is under the flow-by percentage; your 2nd
order review is under the biological impact.
¥ That's where you have the 3 steps. You can come up with a flow-by and assess the impact of
that, but unless you decide what that criterion is that thing is nothing more than a number.
¥ So you are saying they are combined, not in parallel.
¥ In Jennifer's presentation there was a proposal for setting the biological, then from the
biological you get the eco-deficit and with the eco-deficit you could assess what that meant in
terms of setting your flow. It's tougher to see it going that way.
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¥ It's also tough to accept the answers she gave us on where those numbers came from.
¥ If you raise a flag, with the current knowledge, it [eco-deficit] may be a good indicator of how
much change you might see. But I don't have a lot of confidence in looking at those numbers
and using those numbers as any kind of limiting criteria, positive or negative with the current
state of what the models and how much variability they account for. It is a good tool to
evaluate, but I think the level of confidence involved is so broad that it would be really difficult to
set a threshold based on the tool.
¥ I agree with that at this point in time, but it could be refined as we move forward in time and get
more data. Then it could be used as a tool to develop those criteria.
¥ I think you are underestimating how good this model is, and you are equating it with a linear
regression model. The significance of the slopes and y-intercept are very very high; the
confidence is high. What you are uncomfortable with is the ceiling that it is predicting. We see
a response of eco-deficit change along the slope. It is less variable than our hydrology
estimates. It is the best thing, only thing, we have.
¥ In terms of applying it, it is an indicator, not a fixed point, and frankly we still haven’t seen the
final report and gone through it. I accept what you are saying but other than using it to indicate
level of impact, establishing a boundary is difficult to justify at this time.
¥ I don’t know why there’s such consternation over talking about a % biological change from that
curve, the two curves from yesterday for fish and benthos, any more than there is about what
% hydrologic number? It’s the same concept in my mind. That % flow-by is not based on any
statistic, we say others are using these numbers and that’s a good starting point and as more
data is gathered they can change that number in the future. We’re putting too much cold water
on the eco-deficit analysis.
¥ We are for invertebrates using EPT Richness. The state has criteria for EPT rRchness. Your
condition classes have a range of about 10% wide [Jennifer countered this later, saying it was
20%], so the 5% we are talking about is half of a class. It has some basis. As to whether it is
protective or not is a different question, but it wasn’t entirely arbitrary. It was based on some
degree of alteration.
¥ I was impressed with RTI/USGS presentation. I’m not sure about this % change; it’s a little bit
arbitrary.
¥ Let’s talk about the flow-by numbers. We started with 80 and 85%. Kimberly's stuff is hard to
figure out as how to put into a percentage. She is doing it totally differently from what we are
talking about here.
¥ The curves give a solid basis for developing planning tools; it's good work. I’m not entirely
confident in the threshold values, but I am confident in the tool as a means for moving forward
with pursuing eflows concepts.
¥ Whatever number we put into that box will be reviewed or altered over time. We shouldn’t
worry about whether it’s 80 or 85.
¥ I’m fine to say 85% and be done with it.
¥ We could use a range, or pick 80%. We could reference everyone else using 80%. When you
use the eco-deficit piece, it may raise the flag. It may show 80% will cause significant change
at this node or not.
¥ If you look at PHABSIM results, the 80-85% is actually a pretty good choice as flow-by. While
it’s a small sample size of NC data, it supports the general literature. I think we have support
within the state’s work for that.
¥ FL uses 15% loss of habitat, based on most limiting factor.
¥ My feeling, based on PHABSIM, is that the strength of 80-85% is a pretty good range. I think
we have pretty good support within the state to go ahead with that.
¥ Facilitator: So it sounds like there has been a proposal to make the x in flow by 80-85%. Is
that a proposal?
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¥ Based on the PHABSIM work the strength of that work was that it was based on an
unregulated model. Removing 20% of unregulated flow was low impact, but the SIMBASE
could already be a 20% change so you could end up with a 40% change. That would be
predicting impacts to those guilds.
¥ I think you adjust that. We’re working within the bounds of the Legislature's prevailing
conditions. I think we just explain that the model that was done was based on using
unregulated flow and based on that we pick these numbers. Put in a statement that you look
at the cumulative effect of withdrawals and take that into account.
¥ In a system with a significant amount hydro alteration, I’d pick 90 or 95%.
¥ We did use unregulated as baseline for PHABSIM; that was one of the things we wrestled with
while evaluating the RTI/USGS analysis. Where do you set lines between categories? Maybe
setting your flow-by at 80-85 will have more impact on streams with some alteration. If you’re
working on a stream with no or minimal alteration, 80-85% is pretty good. Do you want to steer
potential withdrawals to streams with less alteration?
¥ Like the working rivers approach?
¥ By allowing 20% flow-by you’re not shifting emphasis on those with no impacts.
¥ I don’t know if the legislation has paid enough attention to language; prevailing conditions is not
unregulated.
¥ We absolutely need to use SIMBASE. We’re not precluded from also including unregulated
flow so we can characterize a node with degree of alteration.
¥ Knowing prevailing condition means knowing where it falls on the spectrum. To know how
much you want to move, it helps to know where you are now.
¥ IF DWR chooses not to use eco-deficit as a tool, I’d feel more strongly about using unregulated
flow, to factor in how altered the system is. Maybe we should advise DWR on how to
assess condition of stream, and there are a couple different ways to do that.
¥ Under a planning strategy, we are not compelling anyone to go anywhere; it is an evaluation of
a future state.
¥ Make the range of flow-by 80-90%.
¥ An advantage of using a little wider range is that you give opportunity for constituency groups
to comment on where you think the final should be.
¥ How do we justify the range? What do we have from other areas?
¥ The advantage of a little wider range, the midpoint is something used in other places. We can
point to other places, and we can add qualitative descriptions of reasons of where you’d
want the flag to be triggered earlier, for example less resilient lands, or where you have
cumulative effects. If we were talking about a regulatory program I’d articulate it differently,
but if we’re talking about when do you want to take a closer look, I think it is more appropriate
for certain streams that may be more vulnerable to have a higher percentage to trigger a closer
look.
¥ I think that is true. We don't have data to support 80 or 85 or 90% exactly. Give DWR a range
and let them use discretion.
¥ In the Richter paper Table 2, FL, MI, ME, EU, those percentages are 80-92.5% flow by. FL is
based on its own information, 80-92%; MI is 85-94%; ME is 90%. We’re in the same ballpark.
UK has seasonal- larger % in high flow months. I think we can reference Richter and other
papers and support 80-90%. He’s done the summary but there are other papers.
¥ When we’re saying to maintain ecological integrity, we’ll at some point define what it is.
PHABSIM used the most sensitive guild, etc. In the Richter paper, what are they saying they
are protecting? In MI they say excellent ecological condition; UK had 2 levels of protection. Do
we need a modifier in there or would it confuse things?
¥ These are often in site-specific applications. They are identifying a location where they want to
maintain a certain condition. We’re saying we want to maintain a resilient eco community, and
don’t’ need to get more specific than that.
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¥ If the eco-deficit piece is fleshed out, that may be where we put some qualifiers on it.
¥ If you read the statute, it says the intent is to maintain ecological integrity. Current is assumed
to be maintaining ecological integrity and what we are talking about is the amount of disruption
that allows recovery. So is this 80-90% the amount of disruption from the current condition?
¥ If current is maintaining ecological integrity, deviation must still maintain ecological integrity.
¥ It's to maintain ecological integrity and allow a small amount of disruption.
¥ Judy's language would work: "to maintain a resilient ecological community."
¥ We didn’t really address recovery, but we can imply it.
¥ These permits are not going to change. The permits are permanent, so the notion of coming
back to it is a fallacy.
¥ They could be nonpermanent if used for drought use permits. This is not the purpose of this
long range planning, but I can see scenarios where there could be temporary drought supplies.
¥ I’m not hyped up on resilient ecological community versus ecological integrity.
¥ Does it trigger it if it hits it once or twice, or how many times? We don't necessarily
want to put that number in there.
¥ To that, maybe we want to put in there that DWR will determine at what frequency this value is
exceeded will trigger a flag.
¥ Maybe we could cover that by saying that if the hydrologic models indicate that there is
insufficient water available to meet all needs, essential water uses and ecological flows, then
further review is recommended.
¥ How many times in this report will we refer to this in any other application? If not, we could
define it in a broad sense elsewhere and refer to in general here.
¥ I think we want to lead off with this. It doesn't have to be in great detail, but the rest of the
report explains why.
¥ After wordsmithing, the Board developed the first two bullets of recommendation 1:
• In the basin wide hydrologic models, use 80-90% flow-by as the ecological flow.
• If the basin wide hydrologic models indicate that there is insufficient water available
to meet all needs, essential water uses and ecological flows, then further review is
recommended.
Further Discussion about setting biological change criteria:
After discussing and agreeing upon an ecological flow recommendation, the group discussed how the
ecodeficit tool might be used, particularly focusing on the idea of setting biological change criteria
using the method that was presented by RTI/USGS on Aug. 20.
The main discussion points of the conversation follow.
¥ We need more conversation to pick the percentages as offered by RTI, or say the tool could be
used in this way, here’s a starting point that Division could refine based on additional data, peer
review of RTI work.
¥ The presentation was for the % that represented half the change in EPT Richness associated
with a change in condition class.
¥ We don’t have a comparable thing for fish.
¥ Two ways to set thresholds- a fixed percentage (10% is half of the change of the condition
class), or the percentage varies depending on the starting point of ecological condition
¥ Using benthos AND fish?
• Shannon Weaver Index for fish is more sensitive than benthos
• Could use both, and choose the more sensitive of the two for a trigger
¥ We could recommend we use this ecodeficit tool, and ask the authors of this approach to
recommend these thresholds rather than EFSAB naming the thresholds
• The authors were offering this as a straw man approach
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• Documentation for it is not immediately available (with Sam in TN)
• Could authors be specific about their recommendation about numbers that should be
used in our report
¥ How to establish validity of this approach?
¥ The group discussed how the method was developed in order to try to get an understanding of
it. Ad hoc group members shared ideas that were raised- a recovery-based approach vs. a
working rivers approach, for example.
¥ Using a straight 5% would allow you to get rid of the category (working rivers)
¥ What does a 10% change represent?
• 10% seems extreme for a change in EPT Richness or Shannon Weaver Index.
• The starting point seems relevant.
¥ Using a working rivers concept is beyond the EFSAB charge.
• A 5% change in biological condition is tolerable and has potential to be protective of
resilience.
• 15% on an already impacted system would not protect resiliency.
• The concept gets into values and policy
¥ The amount of flow that equates with a % change is site specific
¥ How comfortable in the large/great streams are we in using both (tools?)
• There is some data in some of the bigger rivers; it’s reflective of the frequency of
streams of particular sizes (fewer larger rivers, fewer data)
¥ Ways to use eco-deficit tool:
• To determine current/relevant biological condition (current eco-deficit)- what is your
current prevailing condition
• To then determine additional biological impact of a proposed flow (future eco-deficit)
• To convert the flow-by using biology to flag
• To use if 80-90% flow-by indicates a big change
• The flow regimes that can be evaluated are endless as long as you can create a flow
duration curve (any proposal can be plugged through tool to see if flag pops up)
¥ If using ecodeficit tool to figure out a flow if you have a target eco-deficit, it would be an
average over an extended period.
¥ We should be clear that we’re recommending using both in parallel; both tools get used every
time the basinwide models are run. This is important since you could maintain 80-90% flowby
and still see a significant biological change.
¥ Previous concern about using EPT categories was that using excellent, fair, good-fair, etc. for
describing existing biological condition would tie it to language from an existing regulatory
program that was not relevant here.
¥ Is it relevant if there are few or many species at a site, when looking at a certain % change?
¥ 5% change is 50% chance of moving to a new class. On average, if done 100 times, ½ will
probably move out of a class, ½ will not. How much of a risk of moving to a new class are we
comfortable with?
¥ Why not to provide a number or range as a threshold?
• Is recommending a % change recommending a policy decision?
• As a group we have different understandings and interpretations of the threshold
concept of the ecodeficit model.
• DENR should have the capacity to determine a threshold themselves
• Authors should be able to provide a recommendation and justify it rather than the Board
setting that point.
• Is it defensible since there is no report from RTI yet, and no publication?
¥ Why provide a number or range as a threshold?
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• If saying DENR should consider change of biological condition between current and
future as a decision criteria, without guidance on how to interpret what is allowable
% change, nothing may happen with it.
• PHABSIM approach would also require an allowable % change to be used as a
decision criterion.
• If x% is recommended as an initial threshold with some explanation of why we chose
the #, it’s at least a point of discussion. If it’s ignored, at least we’ve gone down with
some number and some reasoning.
• Would allow us to frame it as a risk of change if more than this % change happens, to
say further review warranted when this threshold is crossed without defining a
specific action of DENR.
• DENR needs some context for what a % change in bio condition would amount to, and
risk of change in EPT class is most logical (criteria with which to evaluate the
magnitude of change).
Board members present liked the biological index approach presented by RTI/USGS, but consensus
was not reached on whether or not to set a threshold in the recommendation, or what that threshold
should be.
Options
¥ If Board cannot reach consensus on a threshold, we can recommend DENR decide on a
threshold
¥ Ask authors to provide a number recommendation and then Board refers to it rather than
making the recommendation directly.
¥ Board can provide a number/range as an initial/starting point threshold for DENR to use.
¥ If we spent more time with it, with more examples may give us more confidence in a threshold
(wait for RTI report?)
A range of 5-10%change in biological condition was suggested as an initial threshold.
¥ Include an explanation of where numbers came from within the report.
¥ Ask authors to provide examples, advantages, disadvantages of the numbers
¥ In report include language about when you may want a higher % change, when a lower %
change may be appropriate
¥ A straw poll of a proposal to use 5-10% as a threshold resulted in one-1, seven -2’s, and two
4’s
¥ A straw poll of a proposal to use 5-15% as a threshold to reflect the RTI presentation was
polled resulting in three-5s, so this was not further considered
o It would not work to apply 15% across the board as a way to reduce risk
How to move forward between now and September?
¥ Address concerns about defensibility/validity
o Seek report from RTI as documentation (needed)
o Seek additional supporting documentation from other studies, states that could provide
references for using indices as evaluations and particular percent changes (would be
helpful)
§ MI paper with table that has water management zones
§ Others?
¥ Find out absent EFSAB members’ views on the proposal
Everyone present agreed on this part of the recommendation:
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DENR should evaluate the change in current and future biological condition as a decision criterion.
More information is needed before determining support for this part of the recommendation (in
September):
A 5-10% change in biological condition is suggested as a threshold for further review by DENR.
Mary Lou Addor called Jennifer Phelan who provided the following explanation of how they arrived at
the threshold numbers:
The numbers are the ecological flow thresholds assigned to the individual ecological flow categories.
The numbers are not documented specifically in the literature; we used a circuitous route originally
based on the benthic site condition classes that have been adopted and used by the state of NC.
There are 5 site condition classes based on benthos (excellent, good, good-fair, fair, poor) that are
used as indications of quality for benthic health.
We found through an evaluation of EPT Species Richness at each of the monitoring sites across the
state, on average, each site condition class represented a 20% change in benthic biological condition.
From the top to bottom of a class was ~20% change (20% for each class add up to 100%). We then
tried to see if we were to go to a site, and we allow a 20% change in condition would that cause a jump
in site condition class. Would that be too much? The ad hoc group thought, yes it would be too much
of a change in condition, and a half of a site condition class would be good number to recommend,
which would be a 10% change in biological condition. That is where 10% came from. We considered
that we could apply the 10% change to every location, but perhaps that is too much across the board,
maybe it would be better to recommend a greater level of protection to good condition streams. So
that’s where half of the 10% was suggested, which represented a 5% change in biological condition for
the higher-level category. The 10% was meant to apply to the middle condition. Then we followed the
5% gradient going down into the ecological flow categories. That’s the logic behind those 5,10,15%
percentages. The 4th category was 20%, which was another base flow standard. It’s founded within a
preexisting classification system based upon benthic condition, however its gone through several
stages of judgment calls, and is not necessarily supported by flow ecology relationships.
Action item: RTI will share the proposed outline of their report to the EFSAB for feedback about what
should be included, and will complete a description of the biological change threshold methods and
reasoning before the September meeting.
Action item: Chris Goudreau will find MI report to use as a possible reference.
Action item: EFSAB members should share any references from other states, studies that could help
with the biological change threshold decision.
V. Revisiting
Headwaters
Recommendation
Presenter: Chris Goudreau
A Headwaters Steams Recommendation was developed and presented by Chris Goudreau, Judy
Ratcliff, and Jeff Hinshaw. After a brief discussion, the recommendation was refined as follows.
Recommendation 2:
There is limited biological and hydrologic data in headwater streams within North Carolina.
These streams have a higher vulnerability to disturbance, and the broader statewide approach
Ecological
Flows
Science
Advisory
Board
August
20
&
21,
2013
Meeting
Summary
Page
60
of
60
may not adequately reflect the potential for impact to ecological integrity. Therefore, DENR
should identify the subset of headwater streams to receive alternative analysis. (Note for further
explaining- examples of vulnerability, how and in what way. Less water to start could be
converted to intermittent).
This recommendation was supported by a straw poll with eight members or their alternates supporting
the proposal at a “1” –meaning they were in full support of the recommendation; and two members
supporting the recommendation with a “2” – meaning they had a minor reservation.
VI. September
Agenda
Items
Proposed agenda items for the September 24 and 25 include:
1. Recommendation 1: revisit the discussion on the 5, 10 and 15% thresholds assuming RTI provides
the justifications on the thresholds to convene this discussion.
2. Review all recommendations: Ecological Flow Statewide Recommendation, Headwater Streams
Recommendation, Characterization (using stream hydrology) and Coastal Strategy Recommendations.
3. Review justifications provided by writing teams
4. Discuss SIMBASE and recommend that DWR move forward with SIMBASE of today 2013 for future
use.
5. Mark Cantrell will present a table on how to evaluate OASIS nodes.
6. Chris Goudreau will find MI report to use as a possible reference.
7. EFSAB members should share any references from other states, studies that could help with the
biological change threshold decision.
The next meeting of the EFSAB is scheduled for
September 24 and 25, 2013 at the Stan Adams
Educational Center from 9:00am until 4:30pm on
the 24th and 8:30- 4:00 on the 25th. Please
remember to bring lunch and refreshments with
you. Coffee will be available on site and soft
drinks are ($1). Webinar: If you cannot attend
the meeting in person but would like to join us
via the webinar, you can watch the presentations
and listen to the live streaming audio of the
meeting by accessing the link and typing your
name in the space labeled “guest”:
https://denr.ncgovconnect.com/sab/
Meeting Location & Directions: The meeting location is the Stanford M. Adams Training Facility at
Jordan Lake Educational State Forest. Directions are: 2832 Big Woods Road, Chapel Hill, NC 27517.
From Rt 64 and Big Woods Road, it will be the first Forest Service sign on the right. Pass the office
building and continue on through the gate to the education center. For Map link:
http://go.ncsu.edu/stanadams