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HomeMy WebLinkAbout20090969 Ver 4_Mitigation Plans_20091020US Army Corps of Engineers Public Notice for City of Raleigh (Cedar Fork Creek Mitiga... Page 1 of 1 US Army Corps of Engineers Public Notice for City of Raleigh (Cedar Fork Creek Mitigation Site) - 200901917 Harrington, Dorothy SAW [Dorothy.Harrington@usace.army.mil] Sent: Tuesday, October 20, 2009 11:23 AM To: Matthews, Monte K SAW [Monte.K.Matthews@usace.army.mil] Cc: Dailey, Lisa M SAW [Lisa.M.Dailey@usace.army.mil] As you requested, you are hereby notified that Wilmington District, United States Army Corps of Engineers has issued a Public Notice. The text of this document can be found on the Public Notices portion of the Regulatory Division Home Page. Each Public Notice is available in ADOBE ACROBAT (.pdf) format for viewing, printing or download at http://www.saw.usace.army.milANETLANDS/notices.htm1. As with all e-mail attachments, be sure to check for viruses prior to opening the attachment. The current notice involves: PUBLIC NOTICE ACTION ID #: 200901917 2009 20 October The District Engineer has received a draft mitigation plan entitled "Cedar Fork Creek Mitigation Site" proposed for inclusion into the City of Raleigh's umbrella mitigation bank. EXPIRATION DATE: 19 November 2009 POC: Monte Matthews https:Hmail.nc.gov/owa/?ae=Item&t=IPM.Note&id=RgAAAACChSeOTRSCT5TNO706... 10/20/2009 DRAFT MITIGATION PLAN CEDAR FORK CREEK MITIGATION SITE Developed Through PRESERVATION AND RESTORATION OF WETLANDS AND STREAMS ADJACENT TO CEDAR FORK CREEK Wake County, North Carolina PREPARED BY: HAZEN AND SAWYER HAZEN AND SAWYER Environmental Engineers & Scientists 4011 WESTCHASE BOULEVARD RALEIGH, NORTH CAROLINA 27607 AND AXIOM ENVIRONMENTAL, INC. 20 ENTERPRISE STREET, SUITE 7 RALEIGH, NORTH CAROLINA 27607 Axiom Environmental, Inc. JULY 2009 EXECUTIVE SUMMARY The City of Raleigh proposes the establishment of the Cedar Fork Creek stream and wetland mitigation site along Cedar Fork Creek (hereafter the Mitigation Site) located approximately 5 miles southeast of Wake Forest in eastern Wake County. The Mitigation Site is anticipated to be one of several included in an umbrella stream and wetland mitigation bank sponsored by the City of Raleigh. The Mitigation Site is located within the Neuse River Basin in 14-digit USGS Cataloging Unit 03020201180010 of the South Atlantic/Gulf Region (NCDWQ Subbasin Number 03-04-06). The Mitigation Site encompasses approximately 205 acres of land that includes approximately 110 acres of either forested or marsh wetlands. The Mitigation Site currently encompasses approximately 9,100 linear feet of stream associated with Cedar Fork Creek and eight unnamed tributaries to Cedar Fork Creek. Land uses in the vicinity of these wetlands and streams include pasture, agriculture, residential, and unmanaged forest. Protection of Mitigation Site resources along this stream corridor through conservation easements or restrictive covenants will promote the sustainability or improvement of aquatic resources in the Cedar Fork Creek watershed, a watershed under increasing pressure from development, as well as the Little River downstream. Wetland and stream functions currently provided include flood attenuation, slow release of water to maintain stream baseflow, removal of watershed pathogens, a sink for particulate and soluble matter (including nutrients), aquatic and riparian habitat, and landscape-scale wildlife travel corridors. The primary goal of this mitigation project focuses on removing a threat to and preventing a decline of aquatic resources on a watershed scale by an action in or near those aquatic resources. This goal will be accomplished through the following measures: • Protecting, on a watershed scale, a tributary to the proposed reservoir from nonpoint sources of pollution associated with urban services area expansion and development. • Promoting water quality by protecting jurisdictional wetlands adjacent to Mitigation Site streams and tributaries. • Perpetually providing a diverse woody vegetative buffer adjacent to the Mitigation Site's streams and wetlands. • Promoting floodwater attenuation through a) allowing bankfull stream flows to develop over time and b) protecting vegetation on the Mitigation Site's floodplains to increase frictional resistance on floodwaters crossing the Mitigation Site. • Improving aquatic habitat by promoting stable stream banks, shading open waters, and providing structure within the Mitigation Site. • Providing a wildlife corridor and refuge in an area rapidly expanding with residential and commercial development. The Mitigation Site mitigation plan includes 1) preservation of approximately 9,100 linear feet of streams, 2) restoration of approximately 450 linear feet of stream, 3) preservation of approximately 110 acres of jurisdictional wetlands, and 4) establishment of a permanent conservation easement which will encompass all mitigation activities, as well as a 100-foot Cedar Fork Draft Mitigation Plan July 17, 2009 riparian buffer adjacent to Cedar Fork Creek and 50-foot wooded riparian buffers adjacent to all other streams, ponds, and wetlands. Mitigation options outlined in this report are as follows: Proposed Mitigation Proposed Credits Proposed Mitigation Activity Streams Wetlands (linear feet) (acres) Stream Credits Wetland Credits Stream Preservation 9,100 1,820 Stream Restoration 450 450 Wetland Preservation 110 22 Total: 2,270 Total: 22 After completion, the Mitigation Site will offer 2,270 stream mitigation credits and 22 wetland mitigation credits. Please note that proposed mitigation credits provided in the table above are based on an on-site, cursory determination of Mitigation Site resources. Prior to generation of a final mitigation plan, aquatic resources within the Mitigation Site will be delineated in the field and accurately mapped for the generation of quantities. Detailed quantities of streams, wetlands, and wooded buffers within the Mitigation Site will be provided in the final mitigation plan. Three federally protected species are listed for Wake County (USFWS 2008): dwarf wedgemussel (Alasmidonta heterodon), red-cockaded woodpecker (Picoides borealis), and Michaux's sumac (Rhus michauxii). Each of these species is listed as Endangered. Additionally, the bald eagle (Haliaeetus leucocephalus) is protected by the Bald and Golden Eagle Protection Act, and 15 Federal Species of Concern (FSC) are listed for Wake County. While unlikely to support habitat for red-cockaded woodpecker, the Mitigation Site may support suitable habitat for dwarf wedgemussel within stream channels and Michaux's sumac in open areas and along woodland edges. With a range of habitats, including pine forest, mixed hardwood forest, marsh, and open areas, the Mitigation Site may provide suitable habitat for bald eagle and any or all of the 15 FSC species on the USFWS 2008 list. One FSC mussel, green floater (Lasmigona subviridis), was found in the Little River approximately 1 mile downstream of the Mitigation Site outfall during surveys performed in 2007 (The Catena Group 2008). Additionally, the potential creation of a large, open body of water in the near vicinity (the proposed Little River Reservoir) may induce bald eagle to utilize portions of the Mitigation Site for nesting. ii Cedar Fork Draft Mitigation Plan July 17, 2009 TABLE OF CONTENTS EXECUTIVE SUMMARY ........................................................................................................................... i 1.0 INTRODUCTION ............................................................................................................................. .. 1 2.0 OBJECTIVES ................................................................................................................................... .. 1 3.0 SITE SELECTION ............................................................................................................................ .. 2 4.0 SITE PROTECTION INSTRUMENT .............................................................................................. .. 3 5.0 BASELINE INFORMATION ............................................................................................................ 3 5.1 Physiography, Topography, and Land Use ............................................................................. .. 3 5.2 Jurisdictional Streams and Wetlands ...................................................................................... .. 4 5.3 Water Quality .......................................................................................................................... .. 5 5.4 Vegetation ................................................................................................................................. 6 5.5 Soils and Land Form ................................................................................................................ .6 5.6 Federally Protected Species ...................................................................................................... 8 6.0 DETERMINATION OF CREDITS .................................................................................................. .. 9 6.1 Credit Determination ................................................................................................................. 9 6.2 Proposed Credit Release Schedule ............................................................................................ 9 7.0 MITIGATION WORK PLAN .......................................................................................................... 10 7.1 Stream Preservation ................................................................................................................ 10 7.2 Stream Restoration .................................................................................................................. 11 7.3 Wetland Preservation .............................................................................................................. 11 8.0 MAINTENANCE PLAN .................................................................................................................. 12 9.0 PERFORMANCE STANDARDS .................................................................................................... 12 10.0 MONITORING REQUIREMENTS ................................................................................................. 12 11.0 LONG-TERM MANAGEMENT PLAN .......................................................................................... 12 12.0 ADAPTIVE MANAGEMENT PLAN .............................................................................................. 12 13.0 FINANCIAL ASSURANCES .......................................................................................................... 13 14.0 CORPORATE EXPERIENCE .......................................................................................................... 13 15.0 REFERENCES .................................................................................................................................. 15 APPENDICES A. Figures LIST OF FIGURES Figure 1. Project Location Figure 2. Hydrologic Unit Map Figure 3. Drainage Area and Topography Figure 4a. Site Topography - Western Portion Figure 4b. Site Topography - Eastern Portion Figure 5a. Existing Conditions - Overview Figure 5b. Existing Conditions - Western Portion Figure 5c. Existing Conditions - Eastern Portion Figure 6. NRCS Soils Map Figure 7a. Mitigation Credits - Overview Figure 7b. Mitigation Credits - Western Portion Figure 7c. Mitigation Credits - Eastern Portion ui Cedar Fork Draft Mitigation Plan July 17, 2009 LIST OF TABLES Table 1. Existing Stream Characteristics (see Figures 5a through 5c for locations) ......................4 Table 2. Cedar Fork Creek Mitigation Site Soils ............................................................................6 Table 3. FSC Species Listed for Wake County ..............................................................................8 Table 4. Proposed Mitigation Quantities vs. Mitigation Credits ....................................................9 Table 5. Proposed Credit Release Schedule ...................................................................................9 Table 5 (Continued) .......................................................................................................................10 iv Cedar Fork Draft Mitigation Plan July 17, 2009 DRAFT MITIGATION PLAN CEDAR FORK CREEK MITIGATION SITE PRESERVATION AND RESTORATION OF WETLANDS AND STREAMS ADJACENT TO CEDAR FORK CREEK Wake County, North Carolina 1.0 INTRODUCTION The City of Raleigh proposes the establishment of a stream and wetland mitigation project at the Cedar Fork Creek Mitigation Site (Mitigation Site) located approximately 5 miles southeast of Wake Forest in eastern Wake County (Figures 1 and 2, Appendix A). The Mitigation Site is anticipated to be one of several included in an umbrella stream and wetland mitigation bank (Bank) sponsored by the City of Raleigh (Sponsor). The Mitigation Site is located within eight- digit United States Geological Survey (USGS) Hydrologic Unit Code (HUC) 03020201. The Bank is expected to offset unavoidable impacts associated with Sponsor projects, such as the proposed construction of the Little River Reservoir, located immediately southeast of the Mitigation Site (Figures 1 and 2, Appendix A). This document serves as the Draft Mitigation Plan for the Mitigation Site, which encompasses portions of 24 parcels and 205 acres of land. Supporting figures are located in Appendix A. The Mitigation Site generally consists of the area within 100 feet of Cedar Fork Creek and within 50 feet of all other jurisdictional streams, ponds, and wetland areas, and is primarily characterized by mature hardwood forest stands and freshwater marshes within floodplains and adjacent side slopes associated with Cedar Fork Creek and various unnamed tributaries. Within the Mitigation Site, approximately 9,100 linear feet of stream and approximately 110 acres of jurisdictional wetland are proposed for preservation, and approximately 450 linear feet of stream is proposed for restoration. Currently, the Mitigation Site is discontinuous, and it is expected that future acquisitions will generate a continuous easement. Mitigation Site streams and wetlands are situated immediately upstream of the proposed impoundment of the Little River, resulting in perpetual protection of water quality within the proposed water supply watershed. Directions to the Mitigation Site. ? From the City of Raleigh travel north on U.S. Highway 1 ? Travel 5.5 miles and veer right on U.S. Highway 401 North ? Travel 10.8 miles and turn right on Pulley Town Road (SR 2300) ? The Mitigation Site is on the right (south) side of Pulley Town Road ? Point on road near the center of the Mitigation Site Latitude: 35.9251°N, Longitude: 78.4155°W 2.0 OBJECTIVES The primary goals of this stream and wetland mitigation project focus on promoting sustainability and improvement of aquatic resources within the Cedar Fork Creek watershed. Protection of existing aquatic resources (forested wetlands, emergent wetlands, and streams) through conservation easement and/or fee-simple purchase is likely to result in net gains in hydrology, water quality, and habitat functions of Mitigation Site streams and wetlands. Primary goals will be accomplished through the following measures: Cedar Fork Draft Mitigation Plan July 17, 2009 • Protecting, on a watershed scale, a tributary to the proposed reservoir from nonpoint sources of pollution associated with urban services area expansion and development. • Promoting water quality by protecting jurisdictional ponds and wetlands adjacent to Mitigation Site streams. • Perpetually providing a diverse woody vegetative buffer adjacent to Mitigation Site streams, ponds, and wetlands. • Promoting floodwater attenuation through a) allowing bankfull stream flows to develop over time and b) protecting vegetation on Mitigation Site floodplains to increase frictional resistance on floodwaters crossing the Mitigation Site. • Improving aquatic habitat by promoting stable stream banks, shading open waters, and providing structure within the Mitigation Site. • Providing a wildlife corridor and refuge in an area rapidly expanding with residential and commercial development. These goals will be achieved through the following measures: Providing approximately 2,270 stream mitigation credits (preserving approximately 9,100 linear feet of stream channel and restoring approximately 450 linear feet of stream channel). Providing approximately 22 wetland mitigation credits (preserving approximately 110 acres of jurisdictional wetland). Protecting the Mitigation Site in perpetuity with appropriate legal mechanisms (either conservation easement or fee-simple purchase). 3.0 SITE SELECTION Primary considerations for Mitigation Site selection include in-kind mitigation and the potential for protection/improvement of water quality within a portion of North Carolina under developmental pressure. More specifically, considerations include desired aquatic resource functions, hydrological conditions, soil characteristics, aquatic habitat diversity, habitat connectivity, compatibility with adjacent land uses, reasonably foreseeable effects the mitigation project will have on ecologically important aquatic and terrestrial resources, and potential development trends and land use changes. The Mitigation Site is located immediately adjacent (upstream) to the proposed reservoir, and Mitigation Site streams and wetlands will drain directly into the reservoir impoundment. The Mitigation Site supports similar aquatic resources (bottomland hardwood forest, riverine swamp forest, and non-tidal freshwater marsh) to aquatic systems in this portion of the state. According to the Neuse River Basinwide Water Quality Plan (NCDWQ 2008), due to the presence of rare species in the Little River, this watershed should be targeted for land acquisition to protect the riparian area beyond the 50-foot required buffer. The proposed mitigation will result in perpetual protection of wetlands and streams which may contribute drinking water for the region. The Mitigation Site is located in a developing region of the state; therefore, protection of streams and wetlands are expected to result in immediate water quality benefits in the vicinity of the impact reach. Cedar Fork Draft Mitigation Plan July 17, 2009 4.0 SITE PROTECTION INSTRUMENT The Sponsor intends to purchase a conservation easement or land in fee simple for portions of 24 parcels totaling approximately 205 acres. The owners of these parcels have indicated a willingness to have their properties considered for this purpose, but no arrangements have been finalized. Upon approval of the prospectus for the Sponsor's proposed Bank, the Sponsor will delineate jurisdictional boundaries, complete a Mitigation Banking Instrument (MBI), and proceed toward acquiring a conservation easement or land in fee simple for portions of the subject parcels. The Mitigation Site information presented in this Mitigation Plan is based on the optimum Mitigation Site to maximize mitigation credits, and may be adjusted prior to completion of the MBI. The Sponsor will remain the owner of the land or conservation easement or will transfer the land or conservation easement to a land-management entity approved by the Interagency Review Team (IRT). 5.0 BASELINE INFORMATION Mitigation Site aquatic resources are similar to those found within the proposed reservoir site. Ridges and side slopes support a mixture of hardwood forests, agriculture, pasture, and scattered residences. Floodplains adjacent to streams support forested wetlands, emergent wetlands, and some open water. And, in some cases, streams drown into beaver impoundments. Ponds within the Mitigation Site are generally located within agricultural and pasture lands and are occasionally fringed by vegetated wetland areas of various sizes. Forested wetlands include headwater forest (when characterized by seasonal saturation to intermittent inundation and associated with a less than second-order stream), bottomland hardwood forest (when characterized by intermittent to seasonal inundation and associated with a second-order or larger stream), and riverine swamp forest (when characterized by seasonal to semi-permanent inundation). With increasing length of time of surface inundation, forested wetlands grade to non-tidal freshwater marsh. Some marsh areas occur adjacent to small areas of open water. This wetland complex provides hydrology functions such as runoff and flow-velocity reduction, energy dissipation, maintenance of stream baseflow, and groundwater recharge and discharge. Water quality functions include sediment retention, toxicant and nutrient reduction and transformation, and bacterial and viral reduction of watershed runoff. Habitat functions include a complexity of physical structures, dispersion of open waters within vegetated wetlands, a reduction of habitat fragmentation, and travel corridors. 5.1 PHYSIOGRAPHY, TOPOGRAPHY, AND LAND USE The Mitigation Site is located in the Northern Outer Piedmont ecoregion of North Carolina within USGS HUC 03020201 (North Carolina Division of Water Quality [NCDWQ] Subbasin Number 03-04-06) of the Neuse River Basin. Regional physiography is characterized by dissected irregular plains, some low rounded hills and ridges; low- to moderate-gradient streams with mostly cobble, gravel, and sandy substrates are typical (Griffith et al. 2002). On-site elevations range from a high of 400 feet National Geodetic Vertical Datum (NGVD) on slopes adjacent to unnamed tributaries to a low of approximately 290 feet NGVD at the lowest point of the Mitigation Site (USGS Rolesville, North Carolina 7.5-minute topographic quadrangle). Topography within the Cedar Fork Creek watershed is depicted on Figure 3, and Mitigation Site topography is depicted on Figures 4a and 4b. 3 Cedar Fork Draft Mitigation Plan July 17, 2009 The Mitigation Site provides water quality functions to a 4.4-square mile watershed at the discharge of Cedar Fork Creek to the Little River, approximately 1,900 feet east of the Mitigation Site (Figure 3, Appendix A). The watershed is dominated by residential development, agricultural land, forested land, and fragmented forested areas. Impervious surfaces account for less than 5 percent of the upstream watershed land surface. Surrounding area land use is primarily agricultural, with some low-density residential housing and intermittent high density development. On-site land use is characterized by hardwood forest and agricultural land (hay fields and row crop production) (Figures 5a through 5c). Riparian zones and wetland areas are primarily composed of mature hardwood forest. Hardwood forest is characterized by oaks (Quercus spp.), hickories (Cary spp.), red maple (Acer rubrum), sweetgum (Liquidambar styraciflua), and green ash (Fraxinus pennsylvanica). Forested areas appear relatively intact, with several breaks along farm fields and agricultural ponds. Marshes are dominated by emergent vegetation with lesser amounts of shrubs and trees. 5.2 JURISDICTIONAL STREAMS AND WETLANDS The main hydrologic features of the Mitigation Site include Cedar Fork Creek, eight unnamed tributaries, associated floodplains, and some open-water ponds. Mitigation Site streams are first- to third-order, intermittent to perennial, systems that drain an approximately 4.4-square mile watershed (at the discharge of Cedar Fork Creek into the Little River, approximately 1,900 feet east of the Mitigation Site) (Figure 3). The unnamed tributaries tend to be characterized by stable banks and a generally wide, undisturbed forested buffer. Perennial streams within the Mitigation Site may be generally characterized as riverine and upper perennial with unconsolidated bottoms consisting of sand and gravel (R3UB1/2). Intermittent streams within the Mitigation Site may generally be characterized as riverine and upper perennial with streambeds consisting of sand and mud (R3SB4/5). Streams are surrounded by a mixture of mature riparian vegetation and marsh and remain relatively stable, despite expanding developmental pressures. The Mitigation Site currently encompasses approximately 9,100 linear feet of stream channel that are proposed for preservation, including Cedar Fork Creek and eight unnamed tributaries; characteristics of each are included below (Table 1 and Figures 5a through 5c). Table 1. Existing Stream Characteristics (see Figures 5a through 5c for locations) Stream Reach Approximate Stream Length (linear feet) USGS Stream Order USGS Stream Classification In-Field Stream Classification Cedar Fork Creek 1,070 third perennial perennial UT 1 1,230 / 1,340 first intermittent intermittent / perennial UT2 355 first intermittent perennial UT3 200 not shown not shown intermittent UT4 1150 first intermittent perennial UT5 1980 not shown not shown intermittent UT6 205 not shown not shown intermittent UT7 845 first intermittent perennial UT8 725 first intermittent perennial Total 9,100 4 Cedar Fork Draft Mitigation Plan July 17, 2009 The stream proposed for restoration has been degraded and currently exhibits unvegetated wetland characteristics. After restoration activities have been completed, the UT will be approximately 450 linear feet in length and is expected to exhibit characteristics of an intermittent stream. The Mitigation Site will then encompass a total of approximately 9,550 linear feet of stream channel, including Cedar Fork Creek and nine unnamed tributaries. Cedar Fork Creek is depicted as perennial on the USGS 7.5-minute topographic quadrangle. UTs 1, 2, 4, 7, and 8 are depicted as intermittent on USGS mapping; however, UTs 2, 4, 7, and 8 exhibited characteristics of perennial flow during field investigations. UTs 3, 5, and 6 are not depicted on USGS mapping; however, these channels exhibited characteristics of intermittent flow during field investigations. Jurisdictional wetlands are defined by the presence of three criteria: hydrophytic vegetation, hydric soils, and evidence of wetland hydrology during the growing season (Environmental Laboratory 1987). Portions of the Mitigation Site supporting jurisdictional wetlands are characterized by temporarily to seasonally inundated, palustrine, forested wetlands (bottomland hardwood forest); seasonally to semi-permanently inundated, forested wetlands (riverine swamp forest); and semi-permanently flooded, palustrine, emergent wetlands (non-tidal freshwater marsh). Wetlands are underlain by hydric soils that are grey to bluish-gray (gley) in color and are striated with lenses of coarse materials deposited in a fluvial environment. Vegetative communities are composed of various strata, including canopy, relatively open understory, and herbaceous groundcover. Groundwater springs and surface runoff contribute hydrology to these areas, although the dominant hydrological influence is overbank flooding and beaver activity. According to the Cowardin classification (Cowardin et al. 1979), jurisdictional wetlands located within the Mitigation Site along first- to second-order UTs or along the margins of open water may be generally characterized as palustrine, forested, broad-leaved deciduous systems that are saturated, temporarily flooded, or seasonally flooded (PFOIAB/C). Jurisdictional wetlands located along Cedar Fork Creek often show signs of beaver activity and may be generally classified as palustrine, forested, broad-leaved deciduous systems that are semi-permanently to permanently flooded (PFOIF/Hb). The Mitigation Site encompasses approximately 110 acres of wetlands. The approximate locations of jurisdictional wetland areas within the Mitigation Site are depicted on Figures 5a through 5c. 5.3 WATER QUALITY The Mitigation Site is located within the Neuse River Basin in 14-digit USGS Cataloging Unit 03020201180010 of the South Atlantic/Gulf Region (NCDWQ Sub-basin Number 03-04-06) (Figure 2). Cedar Fork Creek has been assigned Stream Index Number 27-57-3 and a Best Usage Classification of WS-II, HQW, NSW (NCDWQ 2008). Streams with a designation of WS-II are protected as water supplies which are generally in predominantly undeveloped watersheds. Local programs to control nonpoint sources and stormwater discharges of pollution are required. These waters are suitable for all Class C uses including aquatic life propagation and survival, fishing, wildlife, secondary recreation, and agriculture. Secondary recreation includes wading, boating, and other uses not involving human body contact with waters on an organized or frequent basis. The supplemental classification HQW (High Quality Waters) 5 Cedar Fork Draft Mitigation Plan July 17, 2009 includes waters which are rated as excellent based on biological and physical/chemical characteristics. All water supply watersheds which are WS-1 or WS-II receive this supplemental classification. The designation NSW (Nutrient Sensitive Waters) includes areas with water quality problems associated with excessive plant growth resulting from nutrient enrichment. NCDWQ has assembled a list of impaired waterbodies according to the Clean Water Act Section 303(d) and 40 CFR 130.7, which is a comprehensive public accounting of all impaired waterbodies. An impaired waterbody is one that does not meet water quality standards including designated uses, numeric and narrative criteria, and anti-degradation requirements defined in 40 CFR 131. Neither Cedar Fork Creek nor the receiving waters of the Little River (proposed for reservoir construction) are listed on the NCDWQ final 2006 303(d) list (NCDWQ 2007). 5.4 VEGETATION The Mitigation Site is characterized primarily by mature hardwood forest, agricultural land, and a few open water ponds. Agricultural land is dispersed along the margins of riparian zones and is characterized by native grasses as well as invasive species including blackberries (Rubus spp.) and milkweed (Asclepias sp.). Hardwood forest dominates the Mitigation Site and is primarily characterized by mesic, floodplain species adjacent to stream channels. Tree and sapling layers include tulip tree (Liriodendron tulipifera), sweetgum (Liquidambar styraciua), American sycamore (Platanus occidentalis), eastern red cedar (Juniperus virginiana), red maple (Acer rubrum), green ash (Fraxinus pennsylvanica), and various oak species (Quercus spp.). Marsh areas associated with beaver impoundments support emergent herbs such as cat-tails (Typha spp.) and wool grass (Scirpus cyperinus), and scattered shrubs such as black willow (Salix nigra) and tag alder (Alnus serrulata). 5.5 SOILS AND LAND FORM Based on county soil survey mapping (MRCS 2008), the Mitigation Site contains ten soil series: Appling sandy loams (Typic Kanhapludults), Buncombe loamy sand (Typic Udipsamments), Chewacla sandy loam (Fluvaquentic Dystrudepts), Colfax sandy loam (Aquic Fragiudults), Durham loamy sand (Typic Hapludults), Enon fine sandy loam (Ultic Hapludalfs), Louisburg loamy sands (Typic Hapludults), Mantachie sandy loams (Fluvaquentic Endoaquepts), Wehadkee and Bibb soils (Fluvaquentic Endoaquepts and Typic Fluvaquents), and Worsham sandy loam (Typic Endoaquults). Soils that occur within Mitigation Site are depicted on Figure 6 in Appendix A and described in Table 2. Table 2. Cedar Fork Creek Miti>ation Site Soils Map Unit Hydric Symbol Ma Unit Name Status Description ApB, Appling sandy loam Non- This series consists of well-drained, moderately-high to ApB2, hydric highly permeable soils of interfluves and slopes along ApC, ApC2, ridges. Slopes are generally between 2 and 15 percent. ApD Depth to the seasonal high water table is greater than 80 inches. Bedrock occurs at a depth of more than 80 inches. Cedar Fork Draft Mitigation Plan July 17, 2009 Table 2 (Continued) Map Unit Hydric Symbol Ma Unit Name Status Description BuB Buncombe loamy sand Non- This series consists of excessively drained, highly to very hydric highly permeable soils of levees on floodplains and is with frequently flooded. Slopes are generally between 0 and 5 hydric inclusions percent. Depth to the seasonal high water table is greater than 80 inches. Bedrock occurs at a depth of more than 80 inches. CmA Chewacla sandy loam Non- This series consists of somewhat poorly drained, hydric moderately-high to highly permeable soils on floodplains with that are frequently flooded. Slopes are generally between hydric inclusions 0 and 2 percent. Depth to the seasonal high water table is between 6 and 24 inches. Bedrock occurs at a depth of more than 80 inches. CnA Colfax sandy loam Non- This series consists of somewhat poorly-drained, slowly hydric permeable soils of depressions around the heads of with drainageways. Slopes are generally between 0 and 3 hydric inclusions percent. Depth to seasonal high water table occurs between 6 and 18 inches. Bedrock occurs at a depth of 40 to 80 inches. DuB, Durham loamy sand Non- This series consists of well-drained soils of interfluves and DuC hydric slopes along ridges with moderately high permeability. Slopes are generally between 2 and 10 percent. Depth to the seasonal high water table is greater than 80 inches. Bedrock occurs at a depth of more than 80 inches. EnB Enon fine sandy loam Non- This series consists of well-drained soils of interfluves hydric with moderately low to moderately high permeability. Slopes are generally between 2 and 6 percent. Depth to the seasonal high water table is greater than 80 inches. Bedrock occurs at a depth of more than 80 inches. LoC Louisburg loamy sand Non- This series consists of well-drained soils of slopes along hydric ridges with very low to high permeability. Slopes are generally between 6 and 15 percent. Depth to the seasonal high water table is greater than 80 inches. Bedrock occurs at a depth of 40 inches. MeA Mantachie sandy loam Non- This series consists of somewhat poorly drained, hydric moderately-high to highly permeable soils on floodplains with that are rarely flooded. Slopes are generally between 0 and hydri c 2 percent. Depth to the seasonal high water table is inclusions between 12 and 18 inches. Bedrock occurs at a depth of more than 80 inches. WoA Wehadkee and Bibb soils Hydric This series is composed of generally even areas of Wehadkee and Bibb soils that consist of poorly drained, moderately-high to highly permeable soils in depressions on floodplains that are frequently flooded. Slopes are generally between 0 and 2 percent. Depth to the seasonal high water table is between 0 and 12 inches. Bedrock occurs at a depth of more than 80 inches. WyA Worsham sandy loam Hydric This series consists of poorly drained soils in depressions that have very low to moderately-low permeability. Slopes are generally between 0 and 3 percent. Depth to the seasonal high water table is between 0 and 12 inches. Bedrock occurs at a depth of more than 80 inches. Cedar Fork Draft Mitigation Plan July 17, 2009 5.6 FEDERALLY PROTECTED SPECIES Species with the classification of Endangered (E), Threatened (T), or officially Proposed (P) for such listing are protected under the Endangered Species Act of 1973 (ESA), as amended (16 U.S.C 1531 et seq.). Three species are federally listed for Wake County by the U.S. Fish and Wildlife Service (USFWS) (USFWS 2008): dwarf wedgemussel (Alasmidonta heterodon), red- cockaded woodpecker (Picoides borealis), and Michaux's sumac (Rhus michauxii). Each of these species is listed as Endangered. Additionally, the bald eagle (Haliaeetus leucocephalus) is protected by the Bald and Golden Eagle Protection Act. In addition to the bald eagle and E, T, and P species, the USFWS list includes a category of species designated as "Federal Species of Concern" (FSC). A species with this designation is one that may or may not be listed in the future (formerly C2 candidate species or species under consideration for listing for which there is insufficient information to support listing). The FSC designation provides no federal protection under the ESA for the species listed. The 15 FSC species listed on the current USFWS list are presented in Table 3. Table 3. FSC Species Listed for Wake County Common Name Scientific name American eel Anguilla rostrata Bachman's sparrow Aimophila aestivalis Carolina darter Etheostoma collis lepidinion Carolina madtom Noturus furiosus Pinewoods shiner Lythrurus matutinus Roanoke bass Ambloplites cavifrons Southeastern myotis Myotis austroriparius Southern hognose snake Heterodon simus Atlantic pigtoe Fusconaia masoni Diana fritillary (butterfly) Speyeria diana Green floater Lasmigona subviridis Yellow lance Elliptio lanceolata Bog spicebush Lindera subcoriacea Grassleaf arrowhead Sagittaria weatherbiana Sweet pinesap Monotropsis odorata Virginia least trillium Trillium pusillum var. virginianum While unlikely to support habitat for red-cockaded woodpecker, the Mitigation Site may support suitable habitat for dwarf wedgemussel within stream channels, and Michaux's sumac in open areas and along woodland edges. With a range of habitats, including pine forest, mixed hardwood forest, marsh, and open areas, the Mitigation Site may provide suitable habitat for any or all of the 15 FSC species on the USFWS 2008 list. One FSC mussel, green floater (Lasmigona subviridis) was found to be present in the Little River approximately 1 mile downstream of the Mitigation Site during surveys performed in 2007 (The Catena Group 2008). Additionally, the creation of a large, open body of water in the near vicinity (the proposed Little River Reservoir) may induce bald eagle to utilize portions of the Mitigation Site for nesting. Cedar Fork Draft Mitigation Plan July 17, 2009 6.0 DETERMINATION OF CREDITS 6.1 CREDIT DETERMINATION The Mitigation Site encompasses Cedar Fork Creek, various unnamed tributaries to Cedar Fork Creek, and associated adjacent jurisdictional ponds and wetlands. Generally, Mitigation Site stream reaches and wetlands are relatively undisturbed; therefore, the mitigation options outlined in this report are as follows. Table 4. Proposed Mitigation Quantities vs. Mitigation Credits Proposed Mitigation Proposed Credits Pro osed Miti ation p g Activity Streams Wetlands Stream Credits Wetland Credits (linear feet) (acres) Stream Preservation 9,100 1,820 Stream Restoration 450 450 Wetland Preservation 110 22 od: Total: 2,270 Total: 22 After completion, the Mitigation Site will offer (at a 5:1 ratio for preservation and a 1:1 ratio for restoration) 2,270 stream mitigation credits and 22 wetland mitigation credits. Please note that proposed mitigation credits provided in the table above are based on an on-site, cursory determination of Mitigation Site resources. Prior to generation of a final mitigation plan, aquatic resources within the Mitigation Site will be delineated in the field and accurately mapped for the generation of quantities. Detailed quantities of streams, wetlands, and wooded buffers within the Mitigation Site will be provided in the final mitigation plan. 6.2 PROPOSED CREDIT RELEASE SCHEDULE A credit release scenario is proposed that complies with interagency guidelines. Under this scenario, the credit release schedule is based upon satisfactory completion of project milestones. Proposed project milestones and percent of credit released are presented in the following table. Table 5. Proposed Credit Release Schedule Task Completion Verification Percent of Credit Release Preconstruction 1. Execution of MBI by the Sponsor, USACE, and other agencies eligible 15 for membership in the Interagency Review Team who choose to execute the agreement 2. Approval of the final mitigation plan 3. Delivery of financial assurances 4. Recordation of the preservation mechanism, as well as the title opinion covering the property that is acceptable to the USACE 5. Execution of stream restoration plan Construction Completion of all initial physical and biological improvements made 15 pursuant to the mitigation plan 9 Cedar Fork Draft Mitigation Plan July 17, 2009 Table 5 (Continued) Task Completion Verification Percent of Credit Release I" Year Monitoring Monitoring Report* 10 2"d Year Monitoring Monitoring Report* 10 3`d Year Monitoring Monitoring Report* 10 4th Year Monitoring Monitoring Report* 10 5`h Year Monitoring Monitoring Report* 15 Bankfull Events Occurrence of two Bankfull Events* * 15 Total 100 * Provided that the channel is stable and all other success criteria are met. ** The release of 15 percent is contingent upon at least two bankfull event occurrences, in separate years, provided that the channel is stable and all other success criteria are met. In the event that less than two bankfull events occur during the monitoring period, the release of the remaining credit shall be at the discretion of the Interagency Review Team. Since the majority of the Mitigation Site is primarily composed of preservation-based mitigation alternatives, an alternative credit release schedule may be suitable. Preservation is not expected to require annual monitoring of stream, wetland, or vegetative parameters; therefore, the majority of credit may be released after the execution of the MBI and approval of this Mitigation Plan. 7.0 MITIGATION WORK PLAN The primary goals of this mitigation plan include 1) protecting a watershed draining to the proposed reservoir from nonpoint sources of pollution associated with urban services area expansion and development, 2) promoting water quality by protecting jurisdictional wetlands adjacent to Mitigation Site streams and tributaries, 3) perpetually providing a diverse woody vegetative buffer adjacent to Mitigation Site streams, ponds, and wetlands, 4) promoting floodwater attenuation by protecting vegetation on Mitigation Site floodplains to increase frictional resistance on floodwaters crossing the Mitigation Site, 5) improving aquatic habitat by promoting stable stream banks, shading open waters, and providing structure within the Mitigation Site, and 6) establishing fee-simple ownership or a permanent conservation easement which will encompass all mitigation activities. Primary activities include stream preservation and restoration and wetland preservation. The mitigation concept as outlined in Figures 7a through 7c is expected to achieve the following: • Preserve approximately 9,100 linear feet of stream channel • Restore approximately 450 linear feet of stream channel • Preserve approximately 110 acres of jurisdictional wetland • Establish an approximately 205-acre area permanently protected by either fee-simple ownership or conservation easement 7.1 STREAM PRESERVATION Stream preservation is being proposed on approximately 1,070 linear feet along Cedar Fork Creek and approximately 8,030 linear feet along various unnamed tributaries to Cedar Fork Creek (Figures 7a through 7c). Based on preliminary analysis and field investigations, 10 Cedar Fork Draft Mitigation Plan July 17, 2009 Mitigation Site streams are relatively stable due to a lack of human-induced impact and a well- developed riparian buffer. Preservation areas will be protected in perpetuity through the establishment of a conservation easement or fee-simple purchase including a minimum 100-foot wooded buffer adjacent to the banks of Cedar Fork Creek and a 50-foot wooded buffer adjacent to all other stream banks. Preservation of the existing stream resources will remove a threat to or prevent the decline of functions such as maintenance of baseflow, floodflow attenuation in adjacent floodplains, energy dissipation during flood events, and in-stream and streamside habitat. 7.2 STREAM RESTORATION Stream restoration is being proposed on approximately 450 feet of a generally linear wet depression that drains to Cedar Fork Creek. This depressed area is highly disturbed, unvegetated, and characterized by human manipulation (grading and crossing), which has resulted in water surface slopes that are equal to the valley slope and the removal of channel bed morphology that supports habitat for aquatic life survival and function. Based upon the slope of the project site and guidance from IRT personnel during an on-site visit, restoration activities will follow stream guidance as presented in Information Regarding Stream Restoration in the Outer Coastal Plain (USACE and NCDWQ 2005). Restoration of the stream is expected to entail 1) beltwidth preparation and grading, 2) channel stabilization, 3) vegetative planting, and 4) culvert installation to provide the landowner with access to all portions of the parcel. Minimal channel excavation is proposed at this time, and it is anticipated that this stream type will develop on the site without intervention. Success criteria for stream restoration will include 1) successful classification of the reach as a functioning stream system (Rosgen 1996) and 2) channel stability indicative of a stable stream system. The restoration area will be protected in perpetuity through the establishment of a conservation easement or fee-simple purchase, including a minimum 50-foot wooded buffer adjacent to the stream banks. 7.3 WETLAND PRESERVATION Wetland preservation is being proposed on approximately 110 acres within floodplains adjacent to Mitigation Site stream reaches (Figures 7a through 7c). Based on preliminary analysis and field investigations, wetlands occur as two general types: forested wetlands and wetlands dominated by emergent vegetation. Forested wetlands are characterized by mature forest vegetation and undisturbed hydric soils, and are subject to jurisdictional wetland hydrology. Emergent wetlands are characterized by a prevalence of emergent herbs with scattered trees and shrubs, hydric soils receiving sediment from upstream sources, and semi-permanent inundation. Preservation areas will be protected in perpetuity through the establishment of a conservation easement or fee-simple purchase, including a minimum 50-foot forested buffer adjacent to jurisdictional wetland margins. Preservation of existing wetland resources will remove a threat to or prevent the decline of functions such as surface and sub-surface storage and retention; will maintain the system's ability to remove pathogens, soluble chemicals (including nutrients), and particulates from the water column; and will provide physical structure for habitat and landscape patch structure for wildlife. 11 Cedar Fork Draft Mitigation Plan July 17, 2009 8.0 MAINTENANCE PLAN Mitigation Site wetland and stream functions will be protected from anthropogenic disturbance through fee-simple ownership or restrictive land uses outlined in a conservation easement. 9.0 PERFORMANCE STANDARDS Preservation-related portions of the project will be deemed successful if photo documentation and post project walkthroughs of the Mitigation Site indicate an undisturbed riparian community, healthy jurisdictional wetland community, and functioning stream channels. Once the project has been deemed successful by the IRT, Mitigation Site wetland and stream functions will be protected through fee-simple ownership or restrictive land uses outlined in conservation easements. Success criteria for stream restoration will include 1) successful classification of the reach as a functioning stream system (Rosgen 1996) and 2) channel stability indicative of a stable stream system. The stream will be visually assessed and photographically documented annually to semi-annually, and any potential problem area(s) will be identified. If a problem area is noted during the review, the area will be evaluated to determine the corrective action required to resolve the problem. Stream channel redevelopment is expected to proceed without excessive shear and/or erosion. Therefore, aggressive stream restoration activities are not proposed at this time. 10.0 MONITORING REQUIREMENTS Based on interagency guidance (Stream Mitigation Guidelines [USACE et al. 2003]), preservation-based monitoring is primarily administrative; therefore, a 5-year monitoring plan for the majority of the Mitigation Site is not required. However, reference photos will be taken and provided to document the status of aquatic resources, including streams, wetlands, and riparian zones. Photos will adequately document the Mitigation Site and will include a detailed description of the locations at which the photos were taken. Stream restoration within the Mitigation Site will be monitored following procedures outlined in the Stream Mitigation Guidelines (USACE et al. 2003). Monitoring efforts of the restoration reach are expected to occur annually for five years or until success criteria, as determined by the IRT, are met. 11.0 LONG-TERM MANAGEMENT PLAN The Mitigation Site is proposed to be protected and managed under fee-simple ownership or restrictive covenants outlined in perpetual conservation easements. Conservation easements will be written to prohibit incompatible uses that might jeopardize the objectives of the Mitigation Site. Easements may be maintained by the City or by a land management entity approved by the IRT. The holder of the easements will be responsible for long-term management. 12.0 ADAPTIVE MANAGEMENT PLAN 12 Cedar Fork Draft Mitigation Plan July 17, 2009 Minimal construction and planting are required for the restoration components of this project; therefore, any changes in the mitigation plan that may occur due to unanticipated construction constraints will be adapted accordingly to meet performance standards. The Mitigation Site will be visited at least annually for a check of the status of aquatic resources. Likely challenges are limited, but may include a loss of vegetation structure due to natural or man-made causes, a growing presence of invasive species, or some type of contaminated spill upstream of the Mitigation Site. In the event that unforeseen changes occur that affect the management or performance standards of the Mitigation Site, the holder of the easements will work with the IRT to determine appropriate measures to rectify deficiencies in the Mitigation Site in order to provide targeted aquatic functions. 13.0 FINANCIAL ASSURANCES The Mitigation Site is anticipated to be part of an umbrella mitigation bank, which will have its own distinct cost center number within the City's budgeting and financial tracking system. Therefore, all accounting for revenues, contract encumbrances, fund transfers, and expenses will be performed and reported independent from all other capital budget or operating budget accounting. A distinct revenue account will be used to account for only stream/wetland- mitigation-dedicated revenues and fund transfers. The Sponsor shall provide the IRT with an annual estimate of the cost of work required by this agreement, and a statement of funds available to perform that work, after each annual budget of the Sponsor is adopted. 14.0 CORPORATE EXPERIENCE Mitigation proposed for the Mitigation Site will involve the establishment, maintenance, and protection of aquatic resources existing within the proposed Mitigation Site in perpetuity. The Mitigation Site is proposed for use toward City of Raleigh public projects. Mitigation credits provided by the Mitigation Site will be used for capital projects performed under the supervision or direction of the City's Public Utilities Department. If possible and practicable, the Mitigation Site may also be available for use by other City departments. Mitigation Site credits will not be offered as mitigation for any other projects without approval of the IRT. The City will maintain contracts with experienced mitigation providers to construct and maintain the mitigation sites, including Hazen and Sawyer, Axiom Environmental, Inc. (Axiom), and EcoScience Corporation (EcoScience). Hazen and Sawyer is an engineering consulting firm that is assisting the City of Raleigh and the U.S. Army Corps of Engineers with the preparation of an Environmental Impact Statement (EIS) and preliminary engineering services for the proposed Little River Reservoir. Since 1985, the Raleigh office of Hazen and Sawyer has completed over 30 Environmental Assessment (EA)/EISs for water and wastewater projects, including water supply reservoirs. Axiom is a Raleigh-based environmental consulting firm that is assisting Hazen and Sawyer with the generation of this draft mitigation plan. The Axiom staff is experienced with coordination among North Carolina natural resources agencies over a wide range of environmental issues ranging from jurisdictional area identification and delineations, jurisdictional area functional assessments, protected species, mitigation site assessments, mitigation site conceptual and detailed planning and construction oversight, mitigation site monitoring, determination of 13 Cedar Fork Draft Mitigation Plan July 17, 2009 mitigation success, and mitigation bank development. Axiom has conducted over 100 investigations of potential mitigation sites, and completed 54 mitigation feasibility studies/prospectuses during the past four years for private landowners, mitigation bankers, and in-lieu fee programs throughout North Carolina. Axiom has also developed many detailed plans for stream, wetland, and riparian buffer mitigation. EcoScience is a Raleigh-based, wholly-owned subsidiary of PBS&J and is assisting Hazen and Sawyer with the field investigation and evaluation of potential mitigation sites. The EcoScience staff is experienced with coordination among North Carolina natural resources agencies over a wide range of environmental issues ranging from jurisdictional area identification and delineations, jurisdictional area functional assessments, protected species, mitigation site assessments, mitigation site conceptual and detailed planning and construction oversight, mitigation site monitoring, determination of mitigation success, and mitigation bank development. 14 Cedar Fork Draft Mitigation Plan July 17, 2009 15.0 REFERENCES Cowardin, Lewis M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classifications of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service. U.S. Government Printing Office, Washington D.C. Environmental Laboratory. 1987. Corps of Engineers Wetlands Delineation Manual. Technical Report Y-87-1. United States Army Engineer Waterways Experiment Station, Vicksburg, Mississippi. Griffith, G.E., J.M. Omernik, J.A. Comstock, M.P. Schafale, W.H. McNab, D.R. Lenat, T.F. MacPherson, J.B. Glover, and V.B. Shelbourne. 2002. Ecoregions of North Carolina and South Carolina. U.S. Geological Survey, Reston, Virginia. Natural Resources Conservation Service (MRCS). 2008. Web Soil Survey. Available online: http://websoilsurvey.nres.usda.gov/ (Reviewed 11/11/2008). Soil Survey Staff, Natural Resources Conservation Service, United States Department of Agriculture. North Carolina Division of Water Quality (NCDWQ). 2007. Final North Carolina Water Quality Assessment and Impaired Waters List (2006 Integrated 305(b) and 303(d) Report) (online). Available: http://h2o.enr.state.nc.us/tmdl/documents/303d_Report.pdf [November 11, 2008]. North Carolina Department of Environment and Natural Resources, Raleigh, North Carolina. North Carolina Division of Water Quality (NCDWQ). 2008. Basinwide Planning Program : Draft Neuse River Basinwide Water Quality Plan -- June 2008. North Carolina Department of Environment and Natural Resources. Raleigh, North Carolina. Rosgen, D. 1996. Applied River Morphology. Wildland Hydrology (Publisher). Pagosa Springs, Colorado. The Catena Group. 2008. City of Raleigh Freshwater Mussel Surveys of the Little River: Wake and Johnston Counties. Prepared for Arcadis. United States Army Corps of Engineers and the North Carolina Division of Water Quality. 2005. Information Regarding Stream Restoration in the Outer Coastal Plain of North Carolina. United States Army Corps of Engineers, United States Environmental Protection Agency, North Carolina Wildlife Resources Commission, North Carolina Division of Water Quality. 2003. Stream Mitigation Guidelines. United States Fish and Wildlife Service (USFWS). 2008. Threatened and Endangered Species in North Carolina (online). Available: http://www.fws.gov/nc-es/es/countyfr.html. 15 Cedar Fork Draft Mitigation Plan July 17, 2009