HomeMy WebLinkAboutDMS_Detecting_WQ_Change_Melia_Haywood-3NCSU EcoStream Conference
August 13-16, 2018
Asheville, NC
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Determining the Likelihood of Detecting Change in
Water Quality Resulting from Stream Restoration
Practices over Mitigation Time Frames
Greg Melia and Casey Haywood
NC Department of Environmental Quality
Division of Mitigation Services
EcoStream Conference
August 13-16, 2018
Asheville, NC
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DMS WQ Sites
Project County
#
Reaches Param Storm Base
Heath Dairy Randolph 2 F,N,S,M Y Y
Millstone Randolph 2 F,N,S,M Y Y
Millstone Randolph 1 F,N,S Y Y
Pen Dell Johnston 1 F Y
Buckwater Orange 1 F,N,S Y Y
Big Harris Cleveland 5 F,N,S Y Y
Big Harris Cleveland 8 M Y
F –Fecal; N –Nutrients; S –Total Suspended Res; M–Macrobenthos
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DMS WQ Sites
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Station Setup and Methods
Drivers for Assessing Higher Level
Ecological Functions Such as Water
Quality and Biology in Mitigation
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Department of Environmental Quality
2010 EEP –DMS
Mitigation
Instrument
DMS Mitigation Plan
Guidance
Claim Uplift
Prove Uplift
The Challenges
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The Challenges
Data Requirements
❑Storm and baseflow separation. Hard to tell
the story without storm data.
❑Number of storms (~15 pers. com NCSU).
❑Based on weather and errors need about 1.5 -2
years for a given treatment phase (i.e. pre -post).
❑Watershed control station.
❑Possible need for reference site(s) pre -con.
The ChallengesThe Challenges
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Optimizing Water Quality Monitoring Plans
❑Objective 4
Where pre-con data is available and/or direct
measurement is required/advisable apply
meaningful criteria and statistical tools to refine
and optimize the post-con monitoring plan.
Project County
#
Reaches Param Storm Base
Heath Dairy Randolph 2 F,N,S,M Y Y
Millstone Randolph 2 F,N,S,M Y Y
Millstone Randolph 1 F,N,S Y Y
Pen Dell Johnston 1 F Y
Buckwater Orange 1 F,N,S Y Y
Big Harris Cleveland 5 F,N,S Y Y
Big Harris Cleveland 8 M Y
F –Fecal; N –Nutrients; S–Total Suspended Res; M–Macrobenthos
MDC =Allows you to estimate the
amount of change necessary to support
statistically reliable change detection.
This is based on the variability observed
in the parameters distribution.
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Baseflow
Base and Stormflow
Optimizing Water Quality Monitoring Plans
Big Harris Pre-con Water Quality Monitoring Scope
Station 0 1 2 3 4 5a 6 7 8 9 10 11 12 13 14 16 17 18 19 20
Fecal
Cond
Solids
NH3
TKN
NOx
TP
Macro
Fish
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Optimizing Water Quality Monitoring Plans
Criteria and Analyses Applied to Pre-con Data
❑Are the existing levels of concern?
Reference Sites
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Optimizing Water Quality Monitoring Plans
Criteria and Analyses Applied to Pre-con Data
❑MDC values >50% were considered too high
Example :Variability in data pre-construction data
for TSS at station 4 produced an MDC of 81%.
High MDC (low probability of reliable change detection)
TSS mg/L
MDC 11.86
MDC%81
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Optimizing Water Quality Monitoring Plans
Criteria and Analyses Applied to Pre-con Data
❑Proposed restoration treatment(s) for reach(s)
represented by sampling have the opportunity to
address the main stressors
Example:Constraints or landowners will not permit
stabilization of ephemeral gullies that are producing
the bulk of the sediment load. Does it make sense to
expect meaningful TSS reductions?
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Optimizing Water Quality Monitoring Plans
Criteria and Analyses Applied to Pre-con Data
❑Pre-con data indicates one or more other stations
will adequately represent the station that was
dropped.
The application of these criteria and the analyses
performed on the pre-con data converted the scope
from this….
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Station 0 1 2 3 4 5a 6 7 8 9 10 11 12 13 14 16 17 18 19 20
Fecal
Cond
Solids
NH3
TKN
NOx
TP
Macro
Fish
Baseflow
Base and Stormflow
Optimizing Water Quality Monitoring Plans
Big Harris Pre-con Water Quality Monitoring Scope
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Optimizing Water Quality Monitoring Plans
Big Harris Post-con Water Quality Monitoring Scope
Station 2 3 5a 6 8 9 10 13 14
Fecal Base and Storm
Cond Baseflow
Solids Stormflow
NH3
TKN
NOx
TP
Macro
Fish
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Optimizing Water Quality Monitoring Plans
Criteria and Analyses Applied to Pre-con Data
❑Data driven.
❑Technically Sound
❑~50% cost-scope reduction between pre and post
❑Optimized.
Questions that Need to be Addressed
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Which parameters and under what land use
histories will detection of change be
possible in mitigation timeframes?
What are the key variables of a reach and its
watershed that govern the likelihood of
detecting change?
What sort of sample sizes and levels of effort
(i.e. cost) will typically be required to enable
statistically reliable detection of change?
How do we arrive at appropriate performance
standards and optimize post-construction
sampling plans?
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DMS Monitoring Plan and Objectives
❑Overarching Goal of DMS Plan.
Provide information and data resources to the
mitigation/restoration community that will assist
practitioners in making decisions about the inclusion
of water quality goals and performance standards at
the reach scale and to augment models and tools
with quality data.
This will reduce the need for direct measurement of
water quality in the long run.
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DMS Monitoring Plan and Objectives
❑Objective 1 –Near Term. Conduct or compile rigorous
water quality monitoring of restoration stream reaches to
determine the reach and watershed attributes that permit
documented improvement within mitigation timeframes.
Provide case examples
Project County
#
Reaches Param Storm Base
Heath Dairy Randolph 2 F,N,S,M Y Y
Millstone Randolph 2 F,N,S,M Y Y
Millstone Randolph 1 F,N,S Y Y
Pen Dell Johnston 1 F Y
Buckwater Orange 1 F,N,S Y Y
Big Harris Cleveland 5 F,N,S Y Y
Big Harris Cleveland 8 M Y
F –Fecal; N –Nutrients; S –Total Suspended Res; M–Macrobenthos
Heath Dairy –NCSU (D.E. Line) larger reach showed storm
load reductions ranging from 41 to 67% for nutrients and
solids. Smaller reach only demonstrated reductions in NH3/4
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DMS Monitoring Plan and Objectives
❑Objective 2 –Long Term.
a.Over the long term compile enough reach outcomes with
simple hypothesis tests (i.e. significance determined Yes or
No between pre and post) from monitored reaches or from
the literature with adequate monitoring practices to generate
a quality reach data set.
b.It is intended that the reach data set will span the reach and
watershed variables that are likely deterministic in supporting
reliable statistical detection of change. (i.e. can we find
thresholds?)
c.develop a model/relationship in which variables determined
to be explanatory yield a probability of detection for each
water quality parameter
❑Example Explanatory Variables .
1.Watershed Proportionality Variables
e.g. drainage area
e.g.treated footage as a proportion of the drainage network
e.g. treated area as a proportion of the drainage area
2.LULC Variables –Continuous Variables
e.g.Proportion forested cover and/or grassland
e.g. Proportion Ag
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DMS Monitoring Plan and Objectives
❑Objective 3
Use the same data to augment/calibrate existing
models and tools to improve their predictive
capability hopefully reducing the need for direct
measurement given its challenges.
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Acknowledgements and Citations
❑Casey Haywood –DMS
❑Jamie Blackwell –NCSU and DMS.
❑Dan Line -NCSU
❑Jean Spooner -NCSU
❑DMS Management.
Jean Spooner, Steven A. Dressing, and Donald W. Meals. 2011. Minimum
detectable change analysis. Tech Notes 7, December 2011. Developed for U.S.
Environmental Protection Agency by Tetra Tech, Inc., Fairfax, VA, 21 p.
Daniel E. Line 2015. Effects of Livestock Exclusion and Stream Restoration on
the Water Quality of a North Carolina Stream. ASABE Vol. 58(6): 1547-1557
Terziotti, Silvia, Capel, P.D., Tesoriero, A.J., Hopple, J.A., and Kronholm, S.C., 2018,
Estimates of nitrate loads and yields from groundwater to streams in the Chesapeake Bay
watershed based on land use and geology: U.S. Geological Survey Scientific Investigations
Report 2017–5160, 20 p., https://doi.org/10.3133/sir20175160.
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DMS S&A Website
https://deq.nc.gov/about/divisions/
mitigation-services/dms-science-
data