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Home My WebLink About20170920 Ver 1_Heron_PostContractMemo_7_25_2017_20170731MEMORANDUM July 31, 2017 RE: Heron Stream and Wetland Mitigation Site Post -IRT Site Visit Notes DMS Project ID: 100014 Attendees: USAGE: Todd Tugwell, Kim Browning NCDWR: Mac Haupt NCWRC: Travis Wilson NCDMS: Melonie Allen, Lindsay Crocker, Jeff Schaffer AXE: Grant Lewis, Kenan Jernigan RS: JD Hamby, Worth Creech On Tuesday July 25, 2017, representatives of the Interagency Review Team (IRT) met with representatives from North Carolina Division of Mitigation Services (NCDMS), Restoration Systems (RS), and Axiom Environmental (AXE) at the Heron Stream and Wetland Mitigation Site to review proposed site mitigation features and approaches. Below is a summary of what was discussed onsite and how those comments will be addressed as the mitigation plan moves forward. This proposal will be further refined in the development of the initiation plan. Please see the proposed asset map (attached) for reference. South Fork: • South Fork enhancement (level II) and preservation was concerning to IRT members from the standpoint of functional uplift. Cattle aren't directly in all parts of stream, and the stream itself is late -evolutionary. Main uplift will result from fencing cattle and invasive treatment, which may have little impact on the current 8+ square -mile drainage area. • It was discussed that buffer widths on South Fork could extend beyond 50 feet (possibly 100 feet) to generate better mitigation uplift. IRT members said the best mitigation option would be enhancement (level II) along the entire reach at a 5:1 or 7.5:1 ratio. • RS decided that mitigation on South Fork is not cost-effective, and therefore no easement will be purchased on the reach. 1101 Haynes St., Suite 211 • Raleigh, NC 27604 • www.restorationsystems.com • Ph 919.755.9490 • Fx 919.755.9492 UT 1: • The upper reaches of UT 1 are now proposed as Enhancement (level I) based on IRT suggestions and discussions. Restoration is proposed to begin upstream of the confluence with UT 2 in an effort to tie the channel into lower restoration reaches where wetland restoration is dependent upon channel depth and location. A restoration approach will be taken from this point downstream. UT 2: • An enhancement (level II) approach with a 2.5:1 credit ratio was agreed upon by all parties. UT 3: • IRT expressed some concern that bringing up the bed on UT 3 may result in the loss of stream flow. This reach was deemed a risk, but a restoration approach was agreed upon. • Stream flow will be monitored throughout the life of the project to prove at least 30 consecutive days of flow annually. All parties agree this is a minimum standard and more that 30 consecutive days is ideal. Other data will be collected as necessary. UT 4: • AXE suggested changing the approach above the confluence with UT 5 to Enhancement (level I) or Restoration. All parties agreed to a Restoration approach for this reach, with justicifation provided in the Mitigation Plan. The installation of the crossing upstream of the easement will require coordination with landowner to re-route and treat runoff from chicken houses and existing path. The remaining downstream reach is proposed as enhancement (level II) at a 2.5:1 ratio. UT 5: • The flow regime of UT 5 was deemed a risk, but a restoration approach was agreed upon. • Stream flow will be monitored throughout the monitoring period to prove at least 30 consecutive days of flow annually. All parties agree this is a minimum standard and more that 30 consecutive days is ideal. Other data will be collected as necessary. UT 6: • After field review of the UT, the IRT agreed that a restoration approach was suitable for the portion of UT 6 within the pasture. • The lower portion, outside of the pasture, was originally proposed as enhancement (level II); however field discussion indicated Restoation approach would be suitable based on the amount of channel work to construct rock fallout structures and/or Terracell as with past projects. UT 7: • There was much discussion of the appropriate approach for mitigation on UT 7. RS proposes using same techniques and methods as other sites where the small pond and dam will be removed. Below the crossing, the rest of the reach will be enhancement (level I). • Stream flow will be monitored throughout the monitoring period to prove at least 30 consecutive days of flow annually. All parties agree this is a minimum standard and more that 30 consecutive days is ideal. Other data will be collected as necessary. 1101 Haynes St., Suite 211 • Raleigh, NC 27604 • www.restorationsystems.com • Ph 919.755.9490 • Fx 919.755.9492 UT 8: • IRT said the preservation at the upstream end of UT 8 would not warrant a 5:1 ratio, and suggested 10:1 instead. Several IRT members suggested restoration of UT 8 upstream to the property boundary; however all members of the IRT did not agree. • RS is now proposing restoration slightly further into the preservation reach as dictated by natural floodplain contours and channel invert tie-in elevations with priority 1 restoration downstream. More detailed studies will be required to determine the extent of restoration; however, streams will be relocated to the most natural position on the existing floodplain. The remaining reach of UT 8 will be proposed as preservation at a 10:1 ratio. • The downstream end of UT 8 is being proposed as Enhancement (level II) at a 2.5:1 ratio and the IRT agreed with this approach. Wetland Restoration/Enhancement: • All proposed wetland approaches were agreed upon by the IRT. Thank you, AAOOP 4-wp�� Worth Creech Restoration Systems 1101 Haynes St., Suite 211 • Raleigh, NC 27604 • www.restorationsystems.com • Ph 919.755.9490 • Fx 919.755.9492 Heron Proposed Asset Table: Riparian Stream Riparian Stream Mitigation Type Stream Wetland Mitigation Mitigation Wetland (linear feet) (acreage) Ratio Units Mitigation Units Restoration 4401 -- 1:1 4401 -- Enhancement (Level I) 1295 -- 1.5:1 863 -- Enhancement (Level 11) 1309 -- 2.5:1 654 -- Preservation 98 -- 10:1 10 -- Wetland Restoration -- 0.33 1:1 -- 0.33 Wetland Enhancement -- 0.61 2:1 -- 0.30 Totals 7103 if 0.94 ac 5928 SMU 0.63 WMU