HomeMy WebLinkAboutVer - Little River Reservoir EIS - 4/23/2010A14;*
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NCDENR
North Carolina Department of Environment and Natural Resources
Beverly Eaves Perdue
Governor
Division of Water Quality
Coleen H. Sullins
Director
Dee Freeman
Secretary
Mr. Monte Matthews
U.S. Army Corps of Engineers
Raleigh Regulatory Field Office
3331 Heritage Trade Drive, Suite 105
Wake Forest, NC 27587
April 23, 2010
Re: Raleigh Little River Reservoir EIS
Conceptual Wetland and Stream Mitigation Plan
City of Raleigh Umbrella Mitigation Bank
Wake County
DWQ #09-0767
Dear Mr. Matthews:
The Division of Water Quality (DWQ) 401 Oversight and Express Review Permitting Unit has
reviewed the above-referenced document for the proposed Little River Reservoir, and we have
numerous concerns regarding mitigation issues associated with the Conceptual Mitigation Plan
(Plan).
One overall concern is the significant shortfall in mitigation presented in the Plan. If mitigation
is required at 1:1 for the flooding impacts and 2:1 for fill impacts (another concern; see below
sections), the plan as reviewed provides only 23% and 54% of the required wetland and stream
mitigation, respectively.
Another overall concern involves the fourth and sixth components of the Plan, which propose
identification of additional mitigation sites within Neuse 03020201. The City of Raleigh should
target sites within the Piedmont portion of the HUC; existing mitigation policies include a
preference for mitigation within the same ecoregion as the impact site. The fourth component
also includes consideration of mitigation opportunities outside Neuse 03020201. Mitigation out
of HUC would be subject to multipliers under DWQ's Adjacent HUC Policy. Mitigation outside
the Neuse basin will not be considered.
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Suite 250, Raleigh, North Carolina 27604-2260 One
Phone: 919-733-17861 FAX: 919-733-68931 Customer Service: 1-877-623-6748 NorthCarolina
Internet: rtunity tunity \ a usln l Natmally
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Mr. Matthews
Conceptual Wetland and Stream Mitigation Plan
City of Raleigh Umbrella Mitigation Bank
Page 2 of 4
Our specific concerns are as follows:
Wetland Mitigation
• The Plan references Federal and State Regulatory guidance that indicates the goal for
mitigating wetland and stream impacts is 1:1 restoration. This is not a goal, but is in fact
a requirement for wetland mitigation in our Water Quality Rules at 15A NCAC 2H
.0506(h)(6). Therefore, in order for a 401 Water Quality Certification to be issued, the
City of Raleigh will be required to include 573 acres of wetland restoration (or creation)
as part of their compensatory mitigation requirements.
The Plan is assuming that wetland mitigation will be required at a 1:1 ratio for flooding
impacts, and a 2:1 ratio for fill (dam construction) impacts. Wetland mitigation in North
Carolina has typically been required at a 2:1 ratio, in order to mitigate for temporal losses
associated with impacts to mature, fully-functioning wetland systems as compared to the
fairly young age and limited functional development of wetland mitigation sites. DWQ
strongly recommends, based on the quality of wetlands to be impacted by the project, that
mitigation for the entire project be required at a 2:1 ratio.
• DWQ does not concur with including credit derived from the assumed formation of
wetlands along the margins of the reservoir as up-front mitigation credit for the proposed
Little River Reservoir. DWQ recommends that if these areas do in fact develop into
functional wetlands suitable for use as compensatory mitigation, the City of Raleigh can
in the future request that these areas be included as part of the City of Raleigh Umbrella
Mitigation Bank. In order for these areas to produce mitigation credit, these areas should
be demonstrated to be a type of wetlands suitable to provide mitigation credit, monitoring
should be conducted for a suitable amount of time (e.g. five to seven years), appropriate
monitoring data will need to be submitted, and these areas should count as creation credit
at a 3:1 ratio. In addition, a protective mechanism would be required to ensure that these
wetlands are protected in perpetuity.
DWQ does not concur with the proposal to receive mitigation credit for the removal of
"undesirable" species from existing wetland areas. If these areas are wooded and
hydrology is unaltered, these activities would not measurably improve wetland function
and would constitute preservation only. Similarly, removal of pine trees does not, in
DWQ's opinion, constitute mitigative activities which maintain or improve water quality.
If USACE wishes to consider these activities as satisfying mitigation requirements
beyond DWQ's 1:1 restoration requirement, lower credit should be given for these areas,
as the level of functional uplift would be minimal.
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Suite 250, Raleigh, North Carolina 27604-2260 One
Phone: 919-733-17861 FAX: 919-733-68931 Customer Service: 1-877-623-6748 NorthCarohna
Internet: rth2o.en a l Xturally
An Equal Oppopportunity 1 Affirmative tive Action ction Employer oyer
Mr. Matthews
Conceptual Wetland and Stream Mitigation Plan
City of Raleigh Umbrella Mitigation Bank
Page 3 of 4
Stream Mitigation
• As discussed in the wetland section above, DWQ recommends that stream mitigation be
required at a 2:1 ratio. Based on data from DWQ permitting files, compensatory
mitigation for wetlands in North Carolina has generally been meeting the goal of "No Net
Loss" ratio, assuming that mitigation offsetting the permitted impacts is considered
successful. However, North Carolina is not meeting the "No Net Loss" goal for streams.
In addition, the quality of the stream systems being impacted warrants mitigation at a 2:1
ratio.
• While DWQ's rules do not include the requirement for stream mitigation to meet the
criteria of 1:1 restoration, DWQ is concerned regarding the amount of preservation credit
being proposed to provide compensatory mitigation for the proposed Little River
Reservoir impact. As discussed above, based the quality of the streams being impacted,
an overall loss of stream linear footage and stream function will result, as preservation
does not replace lost stream function. In addition, the stream corridors proposed for
preservation are already protected by the Neuse River Riparian Buffer Rules, and the
larger streams also have substantial FEMA floodplains which limit activities in these
areas.
• Based on previous discussions with the City of Raleigh's consultants, Eric Kulz with
DWQ recalls that there were questions regarding the applicability of the use of urban
stream restoration sites to provide compensatory mitigation for the proposed Little River
Reservoir impacts, based on the high quality of the potentially-impacted streams. Mr.
Kulz recalls that he was told that these sites (specifically Northwood Circle, Lake
Wheeler Road, Biltmore Hills, and Hammond Road) were being considered for addition
to the City of Raleigh Umbrella Mitigation Bank, but were intended for use to mitigate
other City of Raleigh impacts (e.g. urban stream impacts).
However, based on the Plan, it appears that these sites are now being proposed for
mitigation for the proposed Little River Reservoir impacts. DWQ questions whether
these sites would adequately replace the high aquatic function of the proposed impact
streams.
Overall, DWQ feels that the Plan, despite the fact that it is a conceptual plan, is inadequate to
address the potential mitigation needs for the proposed Little River Reservoir. DWQ personnel
have commented numerous times at meetings and sites visits about the proposed amount of
preservation versus restoration/replacement of lost function, and the Plan only minimally
addressed DWQ's ongoing concerns regarding the ability to adequately mitigate for the proposed
impacts.
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Suite 250, Raleigh, North Carolina 27604-2260 One
Phone: 919-733-17861 FAX: 919-733-68931 Customer Service: 1-877-623-6748
NorthCarolina
Internet: http://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity 1 Affirmative Action Employer AT&id4
Mr. Matthews
Conceptual Wetland and Stream Mitigation Plan
City of Raleigh Umbrella Mitigation Bank
Page 4 of 4
Please feel free to contact me at (919) 733-1786 if you have any questions regarding this project
or our comments.
Sincerely,
" ) &/a
Ian McMillan, Acting Supervisor
401 Oversight and Express Review Program
cc: File Copy
Lauren Witherspoon - DWQ Raleigh Regional Office
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
Location: 2321 Crabtree Blvd., Suite 250, Raleigh, North Carolina 27604-2260 One
Phone: 919-733-17861 FAX: 919-733-68931 Customer Service: 1-877-623-6748 NorthCarohna
Internet: rtunitytunity \ A Affirr ate.nc.usln l Nawnally
An Equal Opportunity \ mative Action Employer oyer