HomeMy WebLinkAbout20140332 Ver 1_follow-up meeting minutes_20141107Strickland, Bev
From: Baker, Virginia
Sent: Monday, November 10, 2014 10:56 AM
To: Strickland, Bev
Subject: FW: Browns Summit follow -up meeting minutes
Attachments: BrownsSummitCreek_ IRT_ SiteMeetingMinutes _7Nov2014.docx;
BrownsSummit_ Pro posed MitigationFeatures _IRT_7Nov2014.pdf
Hi Bev,
Meeting Min 11/7/2014 for laserfishe. Hard copy is in your in box. 20140332 Ginny
- - - -- Original Message---- -
From: Roessler, Chris [ mailto :Croessler @mbakerintl.com]
Sent: Monday, November 10, 2014 10:47 AM
To: Baker, Virginia; Bailey, David E SAW; Tugwell, Todd SAW; Homewood, Sue; Schaffer, Jeff; Melia, Gregory
Cc: Vanstell, Kayne; Hunt, Scott
Subject: Browns Summit follow -up meeting minutes
Hi all -> Thanks again for meeting at the site on Friday. I think it was good example of compromise. Attached are the
updated minutes and map. Todd's perspective could probably be communicated better, so feel free to do that if you're
inclined.
I think the outcome is sufficient but please feel free to provide input if you like. Have a great week, thanks again, Chris
Chris Roessler I Technical Manager I Michael Baker Engineering, Inc., a unit of Michael Baker International
8000 Regency Parkway, Suite 600 1 Cary, NC 27518 1 [D] 919 - 481 -5737 1 [M] 919 - 624 -0905 croessler @mbakerintl.com
www.mbakerintl.com
INTERNATIONAL
Meeting Minutes
BROWNS SUMMIT CREEK RESTORATION PROJECT
EEP Contract No. 5792
Date Prepared:
November 10, 2014
Meeting Date, Time,
November 7, 2014, 10:00 pm
Location:
On -site (Guilford County, NC)
USACE —Todd Tugwel1, David Bailey
NCEEP —Jeff Schaffer, Periann Russell
Attendees:
NCDWR — Ginny Baker, Sue Homewood
Baker —Chris Roessler
Subject:
Third Post - Contract Site visit w/ NCIRT
Recorded By:
Chris Roessler
A third on -site meeting was held on November 7th, 2014 at approximately 10:00 PM to discuss the
Browns Summit Creek Restoration (Full Delivery) Project in Guilford County, NC. Meetings with the IRT
were previously held on April 14th and June 6th —the unchanged results from those meetings are
included in this memo. The purpose of this meeting was to review lower Reach R3 and upper Reach R2
to come to an agreement on the approach. Priority Level I Restoration was initially proposed by Baker
but this was changed to Enhancement Level II (E2) at a 5:1 credit ratio in the second IRT meeting. After
the site had been surveyed, Baker reviewed the approach and thought enough problems were evident
that corrective measures beyond E2 were needed.
Prior to the November 7 meeting, Chris Roessler distributed a PDF titled
BrownsSummit_postSurvey_ Resto ration _ v_ Enhancement_R2_lowerR3.pdf, which showed topography,
photos, and cross sections of the reach sections in question. The bankfull cross sectional areas are
estimated to be 9.7 sf for lower Reach R3 and 12.0 for upper Reach R2. These areas correspond to bank
height ratios of approximately 1.8 to 2.1. Erosion is not widespread but many of the streambanks on the
outside bends are vertical and eroding.
Chris Roessler presented Baker's case to do Priority Level I restoration by stating that the evolutionary
trend for the stream reaches is likely to be down because the channel is incised and widening to create
space for a floodplain bench is expected. The channel is currently 7 to 12 feet wide and it would appear
to need floodprone widths of approximately 15 to 25 feet to be stable (i.e., to reach entrenchment
ratios of > 2.2). Additionally, two locations have riffles that are oriented up valley, which means that
flow vectors are pointed into vertical streambanks and the stream has nowhere to go without causing
significant erosion. Spoil piles are present along the right bank of upper Reach R2, and indicate past
channel manipulation. Finally, floodplain area is available along the existing channel without having to
remove mature trees, making Priority I Restoration more feasible. By reconnecting the channel with its
floodplain and restoring appropriate pattern and dimension, Baker is confident the channel would
remain stable indefinitely.
Todd Tugwell's perspective on the section is that it is currently not very degraded and falls in the middle
category of streams in North Carolina (i.e., not exceptional, but not very degraded). He thinks that if it
were tied to streams that are impacted, the mitigation ratio would not be very high. Also, he believes
that the functional uplift potential for the section is not very high. Todd generally agreed that more
work than fencing out cattle and planting a buffer is warranted.
Given these differing approaches, Chris Roessler suggested a compromise of Enhancement Level I at a
1.5:1 ratio. The two sharp bends will be smoothed, riffle structures will be incorporated to raise the bed,
vertical banks will be laid back and possibly benched, and the spoil piles will be removed, as long as
mature woody vegetation would not be harmed in the process. Additionally, large woody debris will be
incorporated in the form of toe wood, log vanes and /or weirs, and invasive species such as privet will be
treated.
NCDWR thought that Enhancement Level I (E1) is an appropriate approach for this section. Sue
Homewood stated that the mitigation plan should incorporate additional language about functional
uplift that is specific to this section of the project. David Bailey agreed with the E1 approach and stated
that the spoil piles should be removed as part of this effort.
Note: a map for the stream component following this visit is included with this memo.
Reach R5 (notes are unchanged from previous meeting on April 14, 2014)
The group walked along Reach R5 below the spring and agreed with the proposed Enhancement Level II
approach at a 2.5:1 credit ratio. Livestock will be excluded and the buffer will be planted. A gradient
control structure will be installed to prevent the headcut located just below the spring from progressing.
Baker will try to include as much as the channel as possible and still allow cattle to move around the
head of the reach.
Reach R6 (updated from the previous meeting on April 14, 2014)
The Corps and Baker have concluded that this is not a jurisdictional channel but rather a livestock
watering pond in an upland setting. The group has decided that a water quality BMP will be more
appropriate for the replacement of the pond. In effect the pond will be converted to a wetland -type
feature with a low- maintenance weir outlet. It is possible that there will be several tiers of wetland cells
because the Corps recommended that the work extend as far upstream as possible in order to exclude
cattle from the eroded channel. The area included in the project will be planted and placed within the
conservation easement. A cattle crossing will be constructed immediately above the easement.
The credit ratio for developing a BMP channel for Reach R6 was agreed upon at 1.5:1 for the valley
length of the BMP. Under this approach, the existing spillway channel below the pond, which is actively
eroding and filled with concrete debris, will be filled and stabilized.
Reach R4 (notes are from previous meeting on April 14, 2014 except that credit is proposed for a
second stormwater BMP — see fourth paragraph in this section)
This reach will begin where the future Reach R5 and R6 join. Presently, this confluence is located on the
delta at the head of the second pond. It is anticipated that this confluence will be moved upstream and
to the southwest from the existing confluence as part of the Reach R6 proposed mitigation (see above).
The pond at the head of Reach R4 will be removed and replaced with Priority I or shallow Priority II
restoration. This approach will continue downstream to the property line, at which point the incision
and channel erosion become more pronounced.
Once past the property line, the channel will be re- routed slightly to the northeast to line up with the
low point of the valley. The floodplain in this section will be leveled to fill in the existing eroding channel
and remove the relic pond dam.
A second BMP feature will be created on the new floodplain to treat runoff discharge from a 30 -inch
culvert located just above and beyond the right bank. The culvert discharges runoff from much of Broad
Ridge Court, a newly developed subdivision. Baker proposes 1.5:1 credit ratio for the valley length of this
BMP, similar to the BMP along Reach R6. The valley length of this BMP is estimated to be 60 -75 feet. The
outlet is currently causing a major headcut that will continue to migrate. To correct this, a rock -lined
step -pool channel will be constructed to bring the stormwater runoff from the outlet to the floodplain
elevation. Next, a properly -sized basin will capture the runoff, diffuse its energy, and allow water to
spread across the vegetated floodplain, promoting nutrient uptake within the buffer. A stable outlet
channel will be constructed to deliver the runoff to the project reach.
The Corps acknowledged that some of the mature trees toward the lower end of Reach R4 would be
need to be removed for construction but that tree removal should be minimized.
Reach T3 (notes are unchanged from previous meeting on April 14, 2014)
This reach enters the mainstem from the right bank and forms Reach R3 below it. The channel is overly
deep and wide in this location due to a headcut progressing from the mainstem. However, the channel
is also barely intermittent above the headcut.
Baker proposes to remove the headcut and raise the stream to tie in to the Priority 1 restoration on the
mainstem. The reach length in the proposal of 102 feet will be shortened to 50 feet, which should be
within the area of the higher water table created by restoration of the mainstem.
Reach R3 (includes a change on the lower part of the reach from restoration to E2)
Reach R3 begins at the confluence of Reaches T3 and R4. The upper section is currently backwatered
due to a farm pond just downstream. The pond will be removed as part of the Priority 1 restoration of
this reach. Tyler noted the narrow valley width in the lower part of the reach and the need to switch
sides of the channel to save some of the mature trees along it. Chris commented that the assumed
sinuosity is about 1.15. It's actually 1.18 but this can be worked out in the design process.
Per the November 7, 2014 meeting, below the existing and proposed stream crossing Enhancement
Level I at a 1.5:1 credit ratio, as described above, will be implemented for lower Reach R3.
Reach T2 (notes are unchanged from previous meeting on April 14, 2014)
The group didn't discuss Reach T2. Most of this reach is covered by low vegetation. A headcut has
migrated slightly upstream from the mainstem and then it's a small ditch flowing from a pond above.
The proposed work is Enhancement Level II at a 2.5:1 credit ratio to plant and remove livestock from
this reach. A grade control structure will be added to stop the headcut.
Reach R2 (includes a change from restoration to E2)
Reach R2 begins at the confluence of Reaches T2 and R3. Spoil piles are evident in the middle of the
reach beyond the right bank in the middle of the reach. The spoil piles will be removed as discussed in
the wetland mitigation section below.
the,; rp;wh Thp IvArk well hp lernetppl te livesteek emph sien fenr=ing and supplemental planting. Ne vierk
Per the November 7, 2014 meeting, Enhancement Level I at a 1.5:1 credit ratio, as described above, will
be implemented for upper Reach R2 to the barbed wire fence at the property line.
Reach T1 (notes are unchanged from previous meeting on April 14, 2014)
Reach T1 enters from the east on the downstream most property. It has a drainage area of 62 acres and
144 feet of Priority I restoration are proposed. As with all reaches, Baker will describe the functional
uplift that will be attained through restoration in the mitigation plan.
Reach R1 (notes are unchanged from previous meeting on April 14, 2014)
Reach R1 begins at the confluence of Reaches R2 and T1. The bank height ratios are not particularly
high, though there is some channel erosion on the upstream and middle sections. The channel has been
straightened in the past so Priority I restoration is proposed to reestablish natural pattern and eliminate
bank erosion. The IRT accepted this approach because the impacts from implementing it will not be as
high as the reach upstream, which has more mature vegetation.
The downstream end of Reach R1 has been previously manipulated and spoil piles remain in this area.
These will be removed as part of an effort to re- establish and rehabilitate the wetlands in this section.
Wetland Mitigation
The previous iteration of the minutes explained that Baker would map the wetlands to divide them into
different categories according to their existing condition in terms of vegetation and hydrology. This was
done in preparation for the June 6t" meeting with Todd Tugwell.
The different areas may be generally categorized as follows:
1. "Functioning" wetlands — forested areas with hydrology and hydric soils, such as along the right
bank of Reach R1. The hydrology and vegetation are present but in many areas cattle trampling
has impacted the soil structure and ability to percolate water.
2. Degraded wetlands — areas with no wetland vegetation and some hydrology such as along the
corrugated metal pipe at the beginning of Reach R1.
3. Partially- functioning wetlands — mucky areas along the left bank of the middle of Reach R1 that
lacked wetland vegetation.
4. Filled wetlands — areas where spoil has been placed on top of presumed hydric soils, such as
upper Reach R2 and the downstream end of Reach R1.
NCEEP explained that it is important for all wetland mitigation to be used by this project be in the
restoration category (re- establishment or rehabilitation), otherwise it cannot be used according to the
RFP. The federal definitions for wetland restoration and enhancement are listed below.
At the June 6t" meeting, Todd Tugwell expressed that any wetland mitigation would appear to be linked
to changes to the stream channel. Consequently, the wetland mitigation along Reaches R3 (lower) and
R2 will be removed, with the exception of the wetland re- establishment along Reach R2 where spoil
piles will be removed and hydric soils will be at the ground surface.
The credit ratios for the four types of wetland areas are proposed as follows:
1. "Functioning" wetlands — the Corps suggested credit ratios of 3:1.
2. Degraded wetlands — Baker proposes 1.5:1 credit for rehabilitation in these areas. The hydrology
would be improved, as well as the vegetation.
3. Partially- functioning wetlands — Baker proposes 1.5:1 for these areas. Livestock trampling has
adversely affected hydrology and soil structure in these areas. Baker believes that a compacted
layer is promoting surface ponding and preventing suitable /natural drainage. By removing the
livestock and planting appropriate wetland vegetation, Baker believes the soil structure will be
rehabilitated and wetland function will significantly improve.
4. Filled wetlands — Baker proposes wetland re- establishment at a 1:1 credit ratio. By removing the
spoil, hydric soils will be exposed and wetland hydrologic function will be re- established.
Wetland planting will complete the picture.
C'nntarts
• Jeff Schaffer will serve as the NCEEP Project Manager for this project with and Greg Melia will
provide technical assistance during project development and in review of deliverables. Chris
Roessler will be the Baker Project Manager and coordinate /submit project deliverables directly
with Jeff for distribution to all NCIRT team members.
Action Items and Next Steps
• Project Schedule — A separate meeting will be held to conduct the jurisdictional determination
with the Corps. Baker will update NCEEP separately on the expected stream and wetland
mitigation credits following the changes recommended by the IRT.
• After the jurisdictional determination has been conducted, any wetland areas that will be
impacted by the proposed work (filled or drained) will need to be identified and functional
replacement for those losses should be proposed and discussed in the draft mitigation plan.
• USACE requires Jurisdictional (JD) stream /wetland calls for the project. Baker will coordinate
with David Bailey for on -site JD verification prior to mitigation plan submittal.
• Signage will be needed on all conservation easement areas.
This represents Baker Engineering's interpretation of the meeting discussions. If you should find any
information contained in these meeting notes to be in error and /or incomplete based on individual
comments or conversations, please notify me with corrections /additions as soon as possible.
Sincerely,
Chris Roessler, Project Manager
Michael Baker Engineering, Inc.
8000 Regency Parkway, Suite 600
Cary, NC 27518
Phone: 919.481.5737
Email: croessler @mbakercorp.com