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HomeMy WebLinkAbout20140338 Ver 1_RFP Technical Approach_20140404c-or fbp Part 5 - Technical Approach � L��7LiU�lS C APR 4 2014 ... NR -_ WA TM 7i The Maney Farm Stream Mitigation Site (Site) is located in Chatham County approximately 15 miles northwest of the Town of Pittsboro (Figure 1). The project involves restoration and enhancement of Piedmont streams. The project is located within the EEP targeted watershed for the Cape Fear River Basin Hydrologic Unit Code (HUC) 03030002o5oo5o and NCDWQ Subbasin 03 -o6 -04 and is being submitted for mitigation credit in the Cape Fear River Basin HUC 03030002. The proposed Site is located within the Cane Creek Targeted Local Watershed and is discussed in EEP's 2009 Cape Fear River Basin Restoration Priorities (RBRP). This document identifies the need to improve aquatic conditions and habitats in the Cane Creek watershed and notes that there are currently 51 active animal operations in the watershed. The Maney Farm Site is currently maintained as cattle pasture and is one of the 51 animal operations referenced in the RBRP. l4my�is lU ; i+ N:a sign ++ N.; Cane Creek drains to the Haw River, which flows to and tr�ii M�t�i�a ' ,� ��,,������tr. B. Everett Jordan Lake (Jordan Lake). The 2005 NC DWQ Cape Fear River Basinwide Water Quality Plan indicates that the Jordan Lake is a drinking water supply, a primary area for recreation, and a designated Nutrient Sensitive Water, and calls for reduction of non -point source pollution to the lake. The water supply watershed boundary for the Jordan Lake is just 6 miles downstream from the Site. The Cape Fear watershed is also discussed in the 2oo5 North Carolina Wildlife Resource Commission's Wildlife Action Plan where sedimentation is noted as a major issue in the basin. Maps within the Wildlife Action Plan indicate that Priority Species are present along Cane Creek. Restoration at the Site will directly address non -point source stressors by removing cattle from the streams, creating stable stream banks, restoring a riparian corridor, and placing 14.5 acres of land under permanent conservation easement. This project will reduce sediment and nutrient loading, provide and improve instream habitats, provide and improve terrestrial (riparian) habitats, improve stream stability, and improve hydrologic function. The area surrounding the streams proposed for restoration and enhancement is currently fenced to keep cattle in the riparian area and out of the surrounding row crops. Cattle activity is concentrated in the project streams and riparian corridor, resulting in trampled stream banks, minimal riparian vegetation due to overgrazing, and cattle defecate directly in the stream. The proposed work at the Site will provide nutrient and sediment load reduction by removing cattle from the stream, repairing stream bank erosion, raising incised streams, and creating riparian buffers. Reconnection of these creeks to their historic floodplain will filter nutrients before runoff flows off the site. Sources: NC EEP. 2009. Cape Fear River Basin Restoration Priorities. NC DWQ. 2005. Cape Fear River Basinwide Water Quality Plan North Carolina Wildlife Resources Commission. 2005. North Carolina Wildlife Action Plan. Raleigh, NC. qVV Wildlands Engineering, Inc. Page 5.1 Maney Farm Stream Mitigation Site — Part 5 5.1 Project Goals and Objectives The major goals of the proposed stream mitigation project are to provide ecological and water quality enhancements to the Cape Fear River Basin while creating a functional riparian corridor at the site level, providing floodplain habitat and ecological function, and restoring a Piedmont Bottomland Forest community as described by Schafale and Weakley (iggo). Specific enhancements to water quality and ecological processes are outlined below in Table 5.1. Table 5.1 Ecological and Water Quality Goals of the Mitigation Project Water Quality Goals Decrease nutrient and Nutrient input will be decreased by cattle exclusion throughout the Site. Off -site adverse chemical levels nutrient -laden runoff from adjacent farms will be absorbed on -site by filtering flood (RBRP Goal) flows through restored floodplain areas and vernal pools where flood flows can disperse through native vegetation. Increased surface water residency time will provide contact treatment time and groundwater recharge potential. Decrease sediment input A large volume of sediment is being contributed to the system through the failure (RBRP Goal) ofonsite stream banks. Sediment input from unprotected stream banks will be reduced by installing bioengineering and instream structures while creating a stable channel form using natural channel design principles on the restoration reaches. Sediment input from trampled stream banks on enhancement reaches will be decreased by preventing further cattle disturbance and planting the banks. Sediment from off -site sources will be captured by allowing deposition on restored floodplain areas where native vegetation will slow overland flow velocities. Decrease water Stream bed form will be restored and woody structures will be installed to promote temperature and increase re- aeration; this will also help to maintain oxygen levels in the perennial stream dissolved oxygen reaches. Creation of pool zones will lower temperature, helping to maintain concentrations dissolved oxygen concentrations. Establishment and maintenance of riparian buffers will create long -term shading of the channel flow to minimize thermal heating. Ecological Goals Provide and improve Adjacent riparian buffer areas will be restored by planting native vegetation. These terrestrial habitat areas will receive more regular inundating flows, encouraging establishment of a native natural community that connects with other forested areas. Provide and improve A stable channel form and structure appropriate for Piedmont channels will be instream habitat constructed. Introduction of large woody debris, root wads, brush toe meander bends, and native stream bank vegetation will substantially increase habitat value. Wildlands Engineering, Inc. Page 5.2 Maney Farm Stream Mitigation Site — Part 5 5.2 Project Description The following section describes the existing conditions at the Site in terms of geomorphic condition, watershed, soils, geology, cultural resources, species of concern, regulated floodplain zones, and site constraints. 5.2.1 Existing Site Conditions The Site is located in a predominantly rural part of Chatham County, and is currently maintained for cattle pasture and row crops. The parcel directly downstream of the Site is currently under both a Farmland Preservation Trust Fund Easement and a Piedmont Land Conservancy Easement. This parcel also contains a platted NC Wetlands Restoration Program conservation easement from 2002 around South Fork Cane Creek. The proposed conservation easement for this Site will connect these two parcels, creating a protected wildlife corridor. The Site is characterized by moderately sloped valleys dominated by pasture grasses with sparse, intermittent woody vegetation located directly adjacent to the streams. Based on a review of historical aerials (presented in Appendix A), the land use directly adjacent to onsite streams was a mix of farmland and fallow field in 1973. Between 1973 and 1983, the land use on the site transitioned to all farmland. It has been maintained as farmland from 1983 to present. The Site contains one main channel, which is an unnamed tributary (UT) to South Fork Cane Creek (SF), and six tributaries to UT to SF: UT1, UT1B, UTz, UT3, UT4, and UT5. UT to SF generally flows south to north through the property, entering at the southeastern property line at Center Church Road, and exiting at the northern property boundary. UT3., UT3, and UT4 all generally flow southwest to northeast to join UT to SF. UT16 enters the property from a culvert under Center Church Road and joins UT1 near its confluence with UT to SF. UTz and UT5 generally flow east to west tojoin UT to SF. The majority of UT to SF (beginning below its confluence with UT1), the downstream half of UTz, and UTS were identified as perennial streams on October 10 and 11, 2013, using the North Carolina Division of Water Quality (NCDWQ) Stream Identification Forms. A short section of UT to SF (upstream of the UT1 confluence), UT1, UT1B, the upstream half of UTz, UT3, and UT4 were identified as intermittent streams. Copies of these forms are included in Appendix B. The streams are all depicted on Figure 2. Details about the existing streams are provided in Section 5.2.2, below. 5.2.2 Existing Conditions - Streams UT to SF willow oak (Quercus alba). UT to SF enters the Site from a culvert under Center Church Road and flows south to north through a sparsely wooded buffer frequently accessed by cattle. Cattle activity is particularly concentrated near the Center Church Road culvert, and the bed and banks are severely trampled. The stream is overly wide, incised, and entrenched, similar to a Rosgen F -type stream. Although larger trees are present along one or both sides of the channel here, the buffer is heavily grazed and little understory is present. Canopy species include green ash (Fraxinus pennsylvanica), red maple (Acer rubrum), sweetgum (Liquidambarsty ciflua), and Understory species consist of American holly (Ilex opaca), coralberry Wildlands Engineering, Inc. Page 5.3 Maney Farm Stream Mitigation Site — Part 5 (Symphoricarpos orbiculatus), Eastern red cedar (Juniperus virginiana), and Chinese privet (Ligustrum sinense). Common herbaceous species included fescue (Fescue spp.), Nepalese browntop (Microstegium vimineum), and Pennsylvania smartweed (Polygonum pennsylvanicum). The confluence of UT to SF and UT1 approximately 200 feet downstream of the culvert marks UT to SF's transition from an intermittent stream to a perennial stream _ (Figure 2). The cattle wallow in UT to SF below this confluence. UTto SF becomes further incised below this area, and is similar to a Rosgen G -type stream with a low bankfull width -to -depth ratio, a low entrenchment ratio, and a bank height ratio in excess of 1.5. Stream a+ banks are impacted by cattle and alternate fi i w between a trampled and a vertical, sheer state. ° The stream continues in this condition until approximately halfway through the project, where it meanders out into the left floodplain, away from the mature trees. Here the channel cross section decreases and the stream is connected to the floodplain. The stream is stable but lacks pattern and bedform diversity. Invasive Chinese privet and herbaceous pasture grasses dominate the bank vegetation on this section of stream. The riparian buffer from this point down to the project limits alternates between open pasture and small pockets of woods. The pasture areas are vegetated with pasture grasses, rough cocklebur (Xanthium strumarium), horesnettle (Solanum carolinense), and wingstem (Verbesian altemifolia). UT to SF turns to head back through pockets of larger woody vegetation below its confluence with UT4. From this point downstream, UT to SF is again incised with degraded bed and banks due to cattle activity. At the downstream project limits, the stream is under backwater conditions from a downstream wetland complex. provided on Figure 2. Cross sectional surveys were conducted on UT to SF and are provided in Appendix B for review. Three cross sections are provided to illustrate the different forms of UT to SF throughout the site; one on the overly wide, trampled portion of the stream (XS1), one on the incised portion of UT to SF within the wood line (XSz), and one in the open field where the stream is connected to the floodplain (XS3). Due to a lack of reliable bankfull indicators in the maintained channels, bankfull stage was estimated using the published NC Piedmont Regional Curve (Harman et.al., 1999) and the revised INC Piedmont and Mountain Regional Curve (Walker, unpublished) as guides to assist with channel metric calculations. A reachwide pebble count and a riffle loo -count at XSz were conducted on UT to SF to characterize the sediment delivered by the watershed. UT to SF is a sand bed stream. The pebble counts are provided in Appendix B. The locations of the cross sections and sediment surveys are Wildlands Engineering, Inc. Page 5.4 Maney Farm Stream Mitigation Site — Part 5 UT, UTi, an intermittent stream, enters the Site at the southern property line and flows northeast to join UT to SF. The channel flows through a gentle valley, the upstream half of which is maintained as an open pasture, and the downstream half of which is maintained as wooded pasture. Vegetation in the pasture consists of fescue, rough cocklebur, blackberry, and coralberry. The wooded corridor is comprised of green ash, red maple, and sweetgum. The stream is relatively straight through the open pasture but gains some slight pattern within the wood line. Generally, the stream is connected to the floodplain but suffers from bank trampling due to cattle access. The stream most closely resembles a Rosgen C -type stream. UTiB joins UTi within the wood line. Below the UTiB confluence, there is a headcut on UTi which is currently stabilized by large tree roots. Downstream of the headcut, UTs suffers from moderate incision with a bank height ratio of approximately 1.3 for soo linear feet before joining UT to SF. UT1B UT2 UTi.B begins at a culvert under Center Church Road and flows westward to its confluence with UTi. UT3.B is intermittent. The stream is shallow and connected to the floodplain, although cattle have trampled the bed and banks of the stream. A pile of riprap, which may be a remnant check dam, is present approximately halfway through the reach. UT1B flows for approximately ioo linear feet within the project limits before joining UTijust upstream of a headcut. The floodplain vegetation along UTiB is similar to that described for the wooded portion of UTi. UT2 originates as an intermittent stream within the project limits, and becomes perennial approximately halfway down its length as it approaches UT to SF. UT2 flows through a forested pasture with very limited understory due to grazing. The stream is relatively straight but stable. This reach is entirely wooded with minimal understory. Canopy species include green ash, red maple, sweetgum, and few pines (Pinus spp.). A few eastern red cedar saplings and spots of Chinese privet are present. The herbaceous layer is primarily Nepalese browntop because the reach is well shaded. Wildlands Engineering, Inc. Page 9 5.5 Maney Farm Stream Mitigation Site — Part 5 Like UTz, UT3 also originates as an intermittent stream within a pocket of willow oaks within the project limits. The stream is stable with low banks that have been trampled by cattle. UT3 flows from the sparsely wooded buffer into the open pasture and down to meet UT to SF. This reach is dominated by herbaceous species including pasture grasses and pasture weeds like rough cocklebur. Coralberry is present in clusters. Wetter species including Pennsylvania smartweed, soft rush (Juncus effusus), arrrowleaf tearthumb (Polygonum saggittatum), and sedges (Carex spp.) are common along stream corridor, especially where cattle have heavily trampled the channel causing hydrology to spread out. A small pocket of willow oaks is present near the upstream end of the reach. UT4 UT4 also originates as an intermittent stream within the project limits. The stream begins within a small, thinly wooded pocket of vegetation, and then flows through open pasture to meet UT to SF. The wooded area is comprised of red maple, sweetgum, and American holly; the open pasture is similar in species composition to the pasture on UTs. UT4 has low banks and is relatively stable throughout its length despite cattle access and a lack of a riparian buffer. Where UT4 joins UT to SF, Chinese privet has overtaken the stream banks. UTS stream bank. UTS is a perennial stream that enters the project area at a fence line from the eastern side of the property and flows west to meet UT to SF. The stream is incised and disconnected from its floodplain. Banks are heavily eroding and contributing fine sediments downstream, which is choking out available bed habitats. UT5 is most similarto a Rosgen G -type stream; however, UT5 does regain floodplain connection approximately one half way down its length for a short, isolated section. This isolated area is most similarto a Rosgen E/C -type stream. UT5 becomes unstable again belowthis area and continues as a Rosgen G -type stream until the UT to SF confluence. Cattle have access to the entire stream length and have trampled banks, particularly in the lower half of the reach. This reach flows primarily through open woods with little to no understory. The herbaceous layer is dominated by Nepalese browntop with some Christmas ern k Polystichum acrostichoides) present on the The canopy includes green ash, red maple, and river birch (eetula nigra). A cross sectional survey was conducted on UT5 to illustrate the size of the stream where it is connected to the floodplain and in a Rosgen E/C form (XS4). A reachwide pebble count was also collected on UT5 to characterize the sediments delivered by the watershed. UT5 is a silt bed stream, and heavy silt and clay contributions from upstream bank erosion is evident in the riffles. The cross section survey and pebble count data are provided in Appendix B. Wildlands Engineering, Inc. Page 5.6 Maney Farm Stream Mitigation Site — Part 5 5.2.3 Watershed Characterization The Site is located within the Targeted Local Watershed 0303000205oo5o and NCDWQ subbasin o3 -o6- 04. All onsite tributaries drain to South Fork Cane Creek which is classified as Class WS -V: NSW waters by NCDWQ. WS -V waters are usually upstream of waters used for drinking, culinary, or food processing purposes. South Fork Cane Creek is also a Nutrient Sensitive Water, which indicates a need for management of nutrients in its watershed. The Site topography, as indicated on the Crutchfield Crossroads, NC USGS 7.5 minute topographic quadrangle, shows mostly moderately sloped areas throughout the Site (Figure 3). Drainage areas for the project reaches were delineated using z -foot contour intervals derived from the North Carolina Floodplain Mapping Program's zoo? Light Detection And Ranging (LiDAR) data (Figure 4). Land uses draining to the project reaches are primarily cultivated crops, pasture, and forests. The watershed areas and current land use are summarized in Table 5.2, below. Table 5.2 Drainage Areas and Associated Land Use Reach Name Existing NCDWQ Stream Intermittent/ Watershed Predominant Land Use Reach Identification Perennial Area Length Form Scores (acres) (LF) UT to South 51% cultivated crops; 26% Fork Cane 2,8o6 7, 37 27,37 Perennial 211 forested; 17% pasture; 5% Creek impervious; i% residential 47% forested, 27% pasture, 12% developed, UT1 6o8 21 28 Intermittent 21.6 6% impervious, 4% grass; 4% cultivated crops 55% developed, 20% cultivated crop, 13% grass, UT1B 102 25.5 Intermittent 47 9% forested, 3% impervious Intermittent, S9% cultivated crops; 41% UTz 51z z6 3o Perennial 11 forest 55 % pasture, 30% UT3 478 20.75 Intermittent 10.5 forested; 1.5% cultivated crops 45% forested, 30% UT4 273 22.5 Intermittent 19.9 cultivated crops, 25 % pasture 65% cultivated crops; 33% UT 5 467 32.5 Perennial 76 forested; 2/o residential 5.2.4 Soils The proposed project is mapped by the Chatham County Soil Survey. Project area floodplain soils are mapped as Cid silt loam, Cid - Lignum Complex, and Nanford -Badin complex. These soils are described below in Table 5.3. A soils map is provided in Figure 5. Wildlands Engineering, Inc. Page 5.7 Maney Farm Stream Mitigation Site — Part 5 Table 5.3 Project Soil Types and Descriptions Soil Name Description Cid silt loam, 6 -io% Cid silt loam is strongly sloping, moderately deep and slopes moderately well drained soil found on uplands and interfluves. The soil forms in residuum from Carolina Slate Belt rocks and other fine grained rocks. Cid - Lignum Complex, Cid - Lignum is found on gently sloping areas of the upland. It 2 -6% slopes is moderately well drained to somewhat poorly drained. Cid - Lignum has a loamy surface layer and clayey subsoil. Nanford -Badin complex, Nanford- Badin complex is a well- drained soil with low flood 2-6% slopes potential. It is found on uplands, hillslopes and ridges and consists of residuum weathered from slate. Bedrock is within 40 to 6o inches of this soil. Nanford -Badin complex, Nanford- Badin complex at 6 -io% slopes is found on strong 6 -io %slopes slopes on the sideslopes of uplands. This soil is deep and well drained. Bedrock is within 20 to 40 inches of this soil. Source: Chatham County Soil Survey, USDA -NRCS, http: / /efotg.nres.usda.gov 5.2.5 Geology The Site is located in the Carolina Slate Belt of the Piedmont physiographic province. The Piedmont is characterized by gently rolling, well- rounded hills with long low ridges, with elevations ranging from 300 to i.50o feet above sea level. The Carolina Slate Belt consists of heated and deformed volcanic and sedimentary rocks. Approximately SSo to 65o million years ago, this region was the site of a series of oceanic volcanic islands. The underlying geology of the proposed restoration site is mapped as late Proterozoic to Cambrian age (goo to Soo million years in age) felsic metavolcanic rock (CZfv). This unit is described as light gray to greenish, metamorphosed dacitic to rhyolitic flows and tuffs interbedded with mafic and intermediate metavolcanic rock, meta - argillite and metamudstone. Sources: http://www.cieolociy.enr.state.nc.us/uscis/caroIina.htm http•/ /www geology enr state. nc. us / Mineral% zoresources /mineraIresources.htmI 5.2.6 Cultural Resources The site is not located near any sites listed on the National Register with the State Historic Preservation Office (SHPO). The archaeological site files at the North Carolina Office of State Archaeology (OSA) have not been reviewed at this time. All appropriate cultural resource agencies will be contacted for their review and comment prior to any land disturbing activity. 5.2.7 Threatened and Endangered Species The NC Natural Heritage Program (NHP) database was searched for state and federally listed threatened and endangered plant and animal species in Chatham County, NC. Fourteen state listed species are currently listed as threatened or endangered in Chatham County. In addition, three Federally listed species, the Cape Fear Shiner (Notropis mekistocholas), Red - cockaded Woodpecker (Picoides borealis), and Harperella (Ptilimnium nodosum) are listed as Endangered in Chatham County and the Bald Eagle (Haliaeetus leucocephalus) is protected underthe Bald and Golden Eagle Protection Wildlands Engineering, Inc. Page 5.8 Maney Farm Stream Mitigation Site — Part 5 Act (Table 5.4). A pedestrian survey conducted on October 11, 2013 indicated that the site has no potential habitat for federally protected species including the bald eagle, red - cockaded woodpecker, Cape Fear shiner, or Harperella. Wildlands conducted a review of recorded Natural Heritage Elemental Occurrences; no known species occur within 3 miles of the Site. Wildlands will conduct a thorough review of the Site for all state - listed species upon award of contract. Table 5.4 Listed Threatened and Endangered Species in Chatham County, NC Species State Federal Habitat Status Status Vertebrate Bald Eagle Found in forested habitats for nesting and roosting, and (Haliaeetus leucocephalus) T BGPA expanses of shallow water for foraging. Carolina Redhorse T FSC Found in deep water (greater than 6 ft.) with sluggish currents, (Moxostoma sp. 3) silt -sand bottoms, and near large woody debris. Cape Fear Shiner E E Beds in flowing areas of creeks and rivers over gravel, cobble, (Notropismekistocholas) and boulder substrate. Red - cockaded Found in mature pine forest. Excavates cavity exclusively in Woodpecker E E living pine trees. (Picoides borealis) Invertebrate Triangle Floater T Found in moderate flowof small rivers and headwater streams (Alasmidonta undulate) near very stable substrate. Brook Floater E FSC The brook floater is found in high relief streams among (Alasmidonta varicose) boulders in sand. Roanoke Slabshell Found in large rivers and occasionally small creeks. Able to (Elliptio roanokensis) T tolerate large variation in flow levels and high temperatures. Atlantic Pigtoe E FSC Prefers coarse sand and gravel at the downstream edge of riffle (Fusconaia masoni) with fast flowing water. Found in gravel bars, margins of the flowing portions of water Yellow Lampmussel E FSC bodies and cracks in bedrock in both large rivers and small (Lampsilis cariosa) streams. Eastern Lampmussel Found in muddy and sandy areas in streams, rivers and (Lampsilis radiate) T backwater swamps. Creeper Found in shallow water in both small streams and large rivers. (Strophitus undulates) T It inhabits a variety of substrates, from silt to boulder fields. Savannah Lilliput E FSC Prefers shallow water distribution making it particularly (Toxolasma pullus) susceptible to off -road motor vehicle traffic and droughts. Found in mud or sand near stream banks. Occasionally, this Carolina Creekshell E FSC mussel is found in gravelly sand in the main channel of streams (Villosa vaughaniana) and medium rivers. Vascular Plant Indian Physic T Often found in dry open woods with acidic soils. (Gillenia stipulate) Harperella E E Occurs in riparian and wetland habitats. (Ptilimnium nodosum) Southern Skullcap E Found in prairies, upland woods and rock ledges. (Scutellaria australis) Wildlands Engineering, Inc. Page 9 5.9 Maney Farm Stream Mitigation Site — Part 5 Species State Federal Habitat Status Status Veined Skullcap E Found in floodplain forests. (Scutellaria nervosa) Buffalo Clover T Often found near creek banks in sandy soils. (Trifolium ref(exum) BGPA = Bald and Golden Eagle Protection Act; FSC = Federal Species of Concern; T= Threatened; E = Endangered 5.2.8 Floodplain Compliance The Site is represented on the Chatham County Flood Insurance Rate Map Panels 8784 and 8796. There are no FEMA regulated floodplain areas on the Site. 5.2.9 Site Constraints and Access The proposed mitigation approach includes one 25 foot easement break on UT to SF mid -reach and one 25 foot break at the downstream property boundary (see Figure 6). These breaks are for culverted crossings to allow the farmer to access the western fields from Center Church Road. The easement breaks will be fully fenced and gated to prevent cattle access to the streams. A water pipe will also be installed through the mid -reach easement crossing to provide well water to a cattle watering trough on the west side of the site. The crossing and pipe will not dictate the stream design and this area is excluded from the mitigation credit calculation for the site. All easement FIRM , FIRM F1000 IRSUBARCE RATE NON'1'H GMULI:A FAIR M There are no known utilities within the easement boundaries. There are no known airports located within 5 miles of the project site (Figure 1). All streams proposed for mitigation credit provide the required minimum riparian bufferfor Piedmont streams. The easement area will be marked per NCEEP Guidelines for Full Delivery Requirement for Completion of Survey for Conservation Easements (version 13, August 2013). There are no other known constraints on the proposed project site. The entire easement area can be accessed for construction, monitoring, and long term stewardship from existing site access points located along Center Church Road (Figure 6). Wildlands has executed an option agreement to purchase a conservation easement on the property. The conservation easement agreement will ensure the right of entry abilities of Wildlands, its contractors, and the future easement holder in any future land transactions. 5.3 Project Development The Wildlands Team proposes to restore a high quality of ecological function to the streams, riparian corridors, and wetlands on the Site. The project design will ensure that no adverse impacts to existing wetlands or riparian buffers occur. Different management objectives are proposed for different portions of the project area. These activities are discussed below and summarized in Table 5.5. Figure 6 illustrates the conceptual design for the Site. Wildlands Engineering, Inc. Page 5.10 Maney Farm Stream Mitigation Site — Part 5 The major goals of the project will be to improve water quality in the Cane Creek watershed by removing cattle from the riparian corridor and stabilizing eroding stream banks, to achieve improved floodplain functions, and to improve habitat for macro invertebrate and aquatic communities through reestablishment of natural stream function, bed form structure, and reduction in sedimentation. 5.3.1 Stream Mitigation Approach Cattle have caused significant degradation to the onsite streams. UTto SF in particular has been severely impacted and is in various stages of stability throughout the site. The majority of UT to SF is either incised and disconnected from a floodplain or severely trampled from heavy cattle access, or a combination of both. Bed habitats are choked by fine sediments generated from bank erosion, and bedform diversity is poor. Full restoration, using a Priority 1 approach, is proposed on UT to SF to correct the dimension, pattern, and profile deficiencies of the existing stream. Restoration efforts will begin at the Center Church Road culvert, where the stream will be raised to meet the invert of the culvert. Priority z restoration will be used to transition the stream onto the historic floodplain. The width of the Priority z floodplain bench will be minimized while maintaining an entrenchment ratio of at least 2.2 to lessen construction impacts on nearby large woody vegetation: any trees removed as part of the Priority z restoration will be incorporated into the stream design as habitat. As soon as possible, the design will transition to a Priority 1, and the stream will be designed with avoidance of large woody vegetation in mind. Our ultimate goal is to leave as many large trees as possible to provide immediate shade for the stream and woody debris inputs to the newly constructed channel. At the downstream project extents, UT to SF will transition to a Priority z to step the channel down and tie into the backwater created from the wetlands on the downstream property. Throughout UT to SF, bed form diversity will be provided through profile development to include riffles, runs, pools, and glides. The channel dimension will be modified to provide a bankfull — - channel connected to the floodplain, eliminating incision and promoting hydrologic connectivity. Plan form will be adjusted to provide UT to SF with an alignment appropriate for its channel type. UT5 is currently very incised. We propose to fully restore UT5 using a Priority 1 approach to correct the dimension, pattern, and profile deficiencies of the existing stream. Priority z restoration will be used to transition the stream onto the historic floodplain. As discussed for UT to SF, the width of the Priority z floodplain bench will be minimized while maintaining an entrenchment ratio of at least 2.2 to lessen construction impacts on nearby large woody vegetation. All trees removed as part of the Priority z restoration will be incorporated into the stream design as habitat. The existing woody vegetation along UT5 is sparse and the design will route the new stream through Wildlands Engineering, Inc. Page 5.11 Maney Farm Stream Mitigation Site — Part 5 the existing woody vegetation to the greatest extent possible. There is a short, isolated section of existing UT5 channel approximately halfway down the reach that is not incised and is connected to the floodplain. The stream design will tie the new channel into this stable section both upstream and downstream of it. Priority 1 restoration will continue all the way down to the UT to SF confluence. UT1, UT1B, UT2, UT3, and UT4 are all currently relatively stable, but are impacted by cattle. Because none of these streams currently suffer from deep incision, removal of cattle and planting woody vegetation will allow these streams to quickly recover on their own. Enhancement level II, which includes fencing out cattle and planting a native riparian buffer, is proposed for these streams. All reaches on the project will be designed to create new stable, functional stream channels based on reference reach and sediment transport analyses. Dimension, pattern, and profile will be designed to allow for frequent overbank flooding, + provide stable bank slopes, and enable biological lift. This approach will provide hydrologic connectivity between creeks and floodplains and will also create vertical and lateral stability. --- Removing invasive vegetation and establishing •A- 4 � � � stable bank slopes will allow for a native and diverse riparian zone to grow which will improve nutrient removal. A diverse bedform will provide habitat for an increased number of species of insects, fish, and amphibians. This diverse bedform will be established using instream structures appropriate for the geomorphic setting such as log weirs, log vanes, and constructed riffles. Hardwood trees can be harvested from upland areas around the property for log and wood structures. Wildlands will begin the project by identifying the best design approach to meet the stated project objectives and implement the appropriate degree of intervention. A combination of analog, empirical, and analytical design approaches will potentially be used. Reference streams will be identified and will serve as one of the primary sources of information on which designs are based. Modeling and other detailed analyses will be used as appropriate to develop or verify designs. Wildlands has developed a general approach to be used as the basis for stream restoration design and has begun on -going Homogeneity Test coordination with EEP on the procedures. The design approach, which is tailored to each site, 100 continues to develop as additional projects are implemented. Some of the key elements of the methods are described below. �> a 5.3.2 Channel Hydrology 10 Generally, stream designs will be based on a design F" discharge range which, in most cases, will be an approximation of the bankfull discharge but will be selected to meet the objectives of the design. The discharge will be determined through detailed 1 hydrologic analyses using the best available 0 20 40 60 information such as local or regional stream gage Length of Record (yrs) records, empirical regional stream flow estimates, Index -Flood Analysis Results Wildlands Engineering, Inc. Page 5.12 Maney Farm Stream Mitigation Site - Part 5 hydrologic modeling results, and reference stream flows. A preliminary index -flood analysis identified two nearby homogeneous USGS gages, Station 020772oo Hyco Creek and Station 020955365o Buffalo Creek, which will be used during detailed hydrologic modeling. Other discharges (such as baseflow or flows to support instream habitat features) will also be considered during the design process based on the specific project objectives. The design will be refined or validated with sediment transport analysis. 5.3.3 Sediment Transport Sediment transport is an extremely complicated process and the appropriate level of analysis must be determined for each specific design. This determination is based on watershed assessment, local stream observations, reference conditions, and other sources of information. Preliminary sediment sampling efforts throughout the Site have shown that the streams are dominated by fine grained sediments. Streams dominated by sand or silt bed material require more detailed sediment transport studies and must be designed as alluvial channels. These conditions must be considered when establishing design objectives as alluvial channels are expected to adjust their slope, geometry, and bedforms overtime. A capacity analysis with data collection and /or detailed modeling will be an important component of the design. Detailed analysis involves several tools, including SAMwin, Copeland stability curve, and HEC -RAS sediment transport module. However, alluvial channels will most often be designed with controls at key locations to prevent rapid, significant change. 5.3.4 Nutrient Reduction On -site nutrient reduction will be achieved by establishing riparian buffers along both banks and excluding cattle from the streams within the project area. The project area currently consists primarily of agricultural land. An estimate of the percent reduction in nitrogen and phosphorus was made using a spreadsheet based on typical nutrient loading in the Piedmont region. Pre - project conditions reflected agricultural and maintained field conditions within the project area while post - project conditions modeled the project area as wooded. The worksheet estimated that total nitrogen (TN) would be reduced by 37% while total phosphorus (TP) will be reduced by 63 %. A copy of the spreadsheet results can be found in Appendix B. 5.3.5 Vegetation Plan Native riparian buffers a minimum of 5o feet from the proposed top of bank will be planted along all restored and enhanced streams on the Site following construction of the project (Figure 6). The planting plan will be based on an appropriate, nearby reference community and will be developed to restore appropriate strata (canopy, understory, shrub, and herbaceous layers). The canopy will be restored through planting of bare root trees. The understory and shrub layers will be restored through a combination of planting bare root, low growth species and installing live stake shrub species. The herbaceous layer will be restored by seeding the disturbed area with a native seed mix with an emphasis placed on creating good soil contact to encourage germination. The floodplain of UT to SF, as well as the area surrounding the restored and enhanced UT's, will be protected with a conservation easement. Overtime a large native floodplain and stream complex of over 14.5 acres will be created. 5.4 Proposed Mitigation The Site will be a combination of stream restoration and enhancement. 4,748 SMUs are proposed (Table 5.5 and Figure 6). The mitigation credit calculation was derived using the US Army Corps of Engineers' Stream Mitigation Guidance and was based on Wildlands' conceptual design for maximum ecological uplift. Given the existing conditions of the stream channels, the disturbance factors, and the Wildlands Engineering, Inc. Page 5.13 Maney Farm Stream Mitigation Site — Part 5 constraints, management objectives for each reach have been established. The management objective, the mitigation type, and proposed amount of stream mitigation is presented below. Table 5.5 Mitigation Units proposed for the Maney Farm Stream Mitigation Site Stream Miti ation Units Reach Management Objectives Type of Mitigation Length (feet) Ratio Mitigation Units (SMUs) Restore appropriate dimension, pattern, and profile with Priority 1 restoration. UT to SF Install habitat structures, allow bankfull Restoration 3,413 1:1 3,413 floodplain access. Fence out livestock. Establish native riparian buffer. UT1 Fence out livestock. Establish native Enhancement II 608 2.5:1 243 riparian buffer. UT1B Fence out livestock. Establish native Enhancement II 102 2.5:1 41 riparian buffer. UT2 Fence out livestock. Establish native Enhancement II 512 2.5:1 205 riparian buffer. UT3 Fence out livestock. Establish native Enhancement II 478 2.5:1 191 riparian buffer. UT4 Fence out livestock. Establish native Enhancement II 273 2.5:1 109 riparian buffer. Restore appropriate dimension, pattern, and profile with Priority 1 restoration. UT5 Install habitat structures, allow bankfull Restoration S46 1:1 546 floodplain access. Fence out livestock. Establish native riparian buffer. Total 5,932 4,748 SMUs 5.5 Current Ownership The Site is located on a single parcel and owned by one landowner, Darryl M. Lindley, Trustee. An Option Agreement for the general project area shown on Figure 6 has been signed by the property owner and a Memorandum of Option is recorded at the Chatham County Register of Deeds. The landowner has signed the Landowner Authorization Form allowing the United State Army Corps of Engineers (USACE) to enter the site for assessment purposes prior to execution of the Option. Copies of the recorded Memorandum of Option and the Landowner Authorization Form are included in Appendix B. The landowner, parcel identification number, and deed book and page number for the Memorandum of Option are summarized in Table 5.6. Table 5.6 Property Owners for the Maney Farm Stream Mitigation Site Property Owner Parcel ID Number Memorandum of Option Deed Book and Page Number Darryl M. Lindley, Trustee 8795-89-5745 01-713, 0208 -0211 5.6 Project Phasing The Wildlands Team has experience handling tightly - scheduled projects with a number of stakeholders. We understand the importance of clear communication and adherence to deadlines. We will establish additional internal deadlines to keep the project milestones on track. Each task will be staffed with the appropriate technical and management staff to ensure quality and timely completion. Table 5.7 provides a summary of the major project milestones. Wildlands Engineering, Inc. Page 5.1.4 Maney Farm Stream Mitigation Site — Part 5 Table 5.7 Project Schedule for the Maney Farm Stream Mitigation Site 5.7 Success Criteria The stream restoration performance criteria for the project site will follow approved performance criteria presented in the EEP Mitigation Plan Template (version 2.2, 6/o8/2012), the EEP Monitoring Requirements and Performance Standards for Stream and /or Wetland Mitigation (11/07 /2oii), and the Stream Mitigation Guidelines issued in April 2003 by the USACE and NCDWQ. Annual monitoring and semi - annual site visits will be conducted to assess the condition of the finished project. The stream and wetland restoration sections of the project will be assigned specific performance criteria components for hydrology, vegetation, and morphology (streams only). Performance criteria will be evaluated throughout the seven (7) year post- construction monitoring If all performance criteria have been successfully met and two bankfull events have occurred during separate years, Wildlands may propose to terminate stream and /or vegetation monitoring after Year 5, in accordance with the Early Closure Provision in the EEP Monitoring Requirements and Performance Standards for Stream and /or Wetland Mitigation (11/7/2011). An outline of the performance criteria components follows. Wildlands Engineering, Inc. Page 5.3-5 Maney Farm Stream Mitigation Site — Part 5 Proposed Time to Proposed Completion Date Project Milestone Completion (assuming NTP on (from date of NTP) Aril 1, 2014) Task i. CE Document 3 months July 3-, 2014 Task 2. Submit Recorded Conservation 3- year, 3 months July 3-, 203-5 Easement on the Site Task 3. Mitigation Plan Approved by EEP i year April 3-, 2015 Task 4. Mitigation Site Earthwork 2 years, 4 months August 3-, 203-6 Completed Task 5. Mitigation Site Planting and z years, 6 months October 3-, 203-6 Installation of Monitoring Devices Task 6. Baseline Monitoring Report (Including As -Built Drawings) 2 years, 8 months January 3-, 203-7 Approved by EEP Task 7. Submit Monitoring Report #3- to 3 years, 8 months December 3-, 203-7 EEP (meets success criteria) Task 8. Submit Monitoring Report #2 to 4 years, 8 months December 3-, 203-8 EEP (meets success criteria) Task 9. Submit Monitoring Report #3 to 5 years, 8 months December 3-, 203-9 EEP(meets success criteria) Task 3-o. Submit Monitoring Report #4 to 6 years, 8 months December 3-, 2020 EEP (meets success criteria) Task 3-3-. Submit Monitoring Report #5 to 7 years, 8 months December 3-, 2023- EEP (meets success criteria) Task 3-2. Submit Monitoring Report #6 to 8 years, 8 months December 3-, 2022 EEP (meets success criteria) Task 3-3. Submit Monitoring Report #7 to EEP (meets success criteria) and 9 years, 8 months December 3-, 2023 complete Close -Out Process 5.7 Success Criteria The stream restoration performance criteria for the project site will follow approved performance criteria presented in the EEP Mitigation Plan Template (version 2.2, 6/o8/2012), the EEP Monitoring Requirements and Performance Standards for Stream and /or Wetland Mitigation (11/07 /2oii), and the Stream Mitigation Guidelines issued in April 2003 by the USACE and NCDWQ. Annual monitoring and semi - annual site visits will be conducted to assess the condition of the finished project. The stream and wetland restoration sections of the project will be assigned specific performance criteria components for hydrology, vegetation, and morphology (streams only). Performance criteria will be evaluated throughout the seven (7) year post- construction monitoring If all performance criteria have been successfully met and two bankfull events have occurred during separate years, Wildlands may propose to terminate stream and /or vegetation monitoring after Year 5, in accordance with the Early Closure Provision in the EEP Monitoring Requirements and Performance Standards for Stream and /or Wetland Mitigation (11/7/2011). An outline of the performance criteria components follows. Wildlands Engineering, Inc. Page 5.3-5 Maney Farm Stream Mitigation Site — Part 5 5.7.3. Stream Morphological Parameters and Channel Stability Dimension Riffle cross - sections on the restoration reaches should be stable and should show little change in bankfull area, maximum depth ratio, and width -to -depth ratio. Per EEP guidance, bank height ratios shall not exceed 3..2 and entrenchment ratios shall be at least 2.2 for restored channels to be considered stable. All riffle cross - sections should fall within the parameters defined for channels of the appropriate Rosgen stream type. If any changes do occur, these changes will be evaluated to assess whether the stream channel is showing signs of instability. Indicators of instability include a vertically incising thalweg or eroding channel banks. Changes in the channel that indicate a movement toward stability or enhanced habitat include a decrease in the width -to- depth ratio in meandering channels or an increase in pool depth. Remedial action would not be taken if channel changes indicate a movement toward stability. In orderto monitor the channel dimension, one (3.) permanent cross - sections will be installed per 20 bankfull widths along stream restoration reaches, with riffle and pool sections in proportion to EEP guidance. Each cross - section will be permanently marked with pins to establish its location. Cross - section surveys will include points measured at all breaks in slope, including top of bank, bankfull, edge of water, and thalweg. If moderate bank erosion is observed within permanent pool cross - sections during the monitoring period, an array of bank pins will be installed in the permanent cross - section where erosion is occurring for reaches with a bankfull width of greaterthan three feet. Bank pins will be installed on the outside bend of the cross - section in at least three locations (one (3.) in upper third of the pool, one (3.) at the permanent cross - section, and one (3.) in the lower third of the pool). Bank pins will be monitored by measuring exposed rebar and maintaining pins flush to bank to capture bank erosion progression. Annual cross - section and bank pin survey (if applicable) will be conducted in monitoring years one (3.), two (2), three (3), five (5), and seven (7). Profile and Pattern Longitudinal profile surveys will not be conducted during the seven (7) year monitoring period unless other indicators during the annual monitoring indicate a trend toward vertical and lateral instability. If a longitudinal profile is deemed necessary, monitoring will follow standards as described in the EEP Monitoring Requirements and Performance Standards for Stream and /or Wetland Mitigation (3.3./07/2o3.3.) and the 2003 USACE and NCDWQ Stream Mitigation Guidance for the necessary reaches. Substrate Substrate materials in the restoration reaches should indicate a progression towards or the maintenance of coarser materials in the riffle features and smaller particles in the pool features. A reach -wide pebble count will be performed in each restoration reach each year for classification purposes. A pebble count will be performed at each surveyed riffle to characterize the pavement. Wildlands Engineering, Inc. Page 5.3.6 Maney Farm Stream Mitigation Site — Part 5 5.7.2 Hydrology Two (2) bankfull flow events must be documented on the restoration reaches within the seven (7) year monitoring period. The two (2) bankfull events must occur in separate years. Stream monitoring will continue until success criteria in the form of two bankfull events in separate years have been documented. Bankfull events will be documented using photographs and either a crest gage or a pressure transducer, as appropriate for site conditions. The selected measurement device will be installed in the stream within a surveyed riffle cross - section. The device will be checked at each site visit to determine if a bankfull event has occurred. Photographs will also be used to document the occurrence of debris lines and sediment deposition. 5.7.3 Vegetation The final vegetative success criteria will be the survival of 210 planted stems per acre in the riparian corridor at the end of the required monitoring period (year seven (7)). The interim measure of vegetative success for the site will be the survival of at least 320 planted stems per acre at the end of the third (3) monitoring year and at least 26o stems per acre at the end of the fifth (5) year of monitoring. Planted vegetation must average 10 feet in height in each plot at the end of the seventh (7) year of monitoring. If this performance standard is met by year five (5) and stem density is trending towards success (i.e., no less than 26o five year old stems /acre), monitoring of vegetation on the site may be terminated with written approval by the USACE in consultation with the NC Interagency Review Team. The extent of invasive species coverage will also be monitored and controlled as necessary throughout the required monitoring period (year five or seven). Vegetation monitoring quadrants will be installed across the restoration site to measure the survival of the planted trees. The number of monitoring quadrants required will based on the EEP monitoring guidance documents (version 1.5, 6/08/12). Vegetation monitoring will occur in the fall and will follow the CVS -EEP Protocol for Recording Vegetation (2006). 5.7.4 Other Parameters Photo Reference Stations Photographs will be taken once a year to visually document stability for seven (7) years following construction. Permanent markers will be established and located with GPS equipment so that the same locations and view directions on the site are photographed each year. Photos will be used to monitor restoration and enhancement stream reaches as well as vegetation plots and wetland areas. Longitudinal reference photos will be established at the tail of riffles approximately every Zoo LF along the channel by taking a photo looking upstream and downstream. Cross - sectional photos will be taken of each permanent cross - section looking upstream and downstream. Reference photos will also be taken for each of the vegetation plots and within wetland areas. Representative digital photos of each permanent photo point, cross - section and vegetation plot will be taken on the same day that the stream and vegetation assessments are conducted. The photographer will make every effort to consistently maintain the same area in each photo overtime. Wildlands Engineering, Inc. Page 5.17 Maney Farm Stream Mitigation Site — Part 5 Photographs should illustrate the site's vegetation and morphological stability on an annual basis. Cross - section photos should demonstrate no excessive erosion or degradation of the banks. Longitudinal photos should indicate the absence of persistent bars within the channel or vertical incision. Grade control structures should remain stable. Deposition of sediment on the bank side of vane arms is preferable. Maintenance of scour pools on the channel side of vane arms is expected. Visual Assessments Visual assessments will be performed along stream reaches on a semi - annual basis during the seven (7) year monitoring period. Problem areas will be noted such as channel instability (i.e. lateral and /or vertical instability, instream structure failure /instability and /or piping, headcuts), vegetation health (e.g. low stem density, vegetation mortality, invasive species or encroachment), beaver activity, or livestock access. Areas of concern will be mapped and photographed accompanied by a written description in the annual report. Problem areas with be re- evaluated during each subsequent visual assessment. Should remedial actions be required, recommendations will be provided in the annual monitoring report. eenthic Macroinvertebrates If required by NCDWQ as part of the projects permitting process, benthic macroinvertebrate sampling will be performed on the restored site. Any required sampling will be performed using NCDWQ Standard Operating Procedures for Benthic Macroinvertebrates, July 2006. 5.7.5 Reporting Performance Criteria Using the EEP Baseline Monitoring Plan Template (version 2.0, 10/14/10), a baseline monitoring document and as -built record drawings of the project will be developed within 6o days of the planting completion and monitoring installation on the restored site. Monitoring reports will be prepared in the fall of each year of monitoring and submitted to EEP. These reports will be based on the EEP Monitoring Report Template (version 1.5, 6/08/12). The monitoring period will extend seven years beyond completion of construction or until performance criteria have been met per the criteria stated in the EEP Monitoring Requirements and Performance Standards for Stream and /or Wetland Mitigation (111712011). 5.7.6 Maintenance and Contingency Plans The Wildlands Team will develop necessary adaptive measures or implement appropriate remedial actions in the event that the site or a specific component of the site fails to achieve the success criteria outlined above. The project — specific monitoring plan developed during the design phase will identify an appropriate threshold for maintenance intervention based on the monitored items. Any actions implemented will be designed to achieve the success criteria specified previously, and will include a work schedule and updated monitoring criteria. Wildlands Engineering, Inc. Page 5.18 Maney Farm Stream Mitigation Site — Part 5 Figure 2 Site Map W I L D L A N D 5 0 325 Feet Maney Farm Stream Mitigation Site Oft N G I N E E R I N G I I t Cape Fear River Basin 03030002 Chatham County, NC Project Location 579', .i. Proposed Conservation Easement f f67 / JP +l x596 - AIAMANCE CO_ ~ _— _Ca•nt.:Ch S.� – - -- _ CHATHAM CO I UL -A, 5� outh Bark Ch - .r �` F o i 1.,..�.,._�.� I i I sy, I J Mz f2T5 e +( Ayc ? -?v, � u � t ra' G u0 C �0 '� rf 0 Crutt }r, roads, USGS 7.5 minute topographic quadrangle I Figure 3 Topographic Map witwWlLDLANDS 0 2,000 Feet Maney Farm Stream Mitigation Site E N G IN E E RING I I I Cape Fear River Basin 03030002 ?s XIIr61 x. S „6 � Chatham County, NC Figure 4 Watershed Map WILD LANDS p 600 Feet Maney Farm Stream Mitigation Site EN G IN E = R I N G I I I Cape Fear River Basin 03030002 Chatham County, NC I � i `yfi MAMA i ti 'ry .._ AAA Ta V NaC .t �. �t fy Ksk -O 4, a ;- AaB ,r r �I NaC %ZVAW, WILDLANDS ENGINEERING 0 400 Feet I I I t !minim 16,m�i Project Location Conservation Easement(14.51 Acres) Project Streams ChA- Chewacla silt loam, 0 -2% slopes CkC- Cid silt loam, 6 -10% slopes CmB- Cid - Lignum complex, 2 -6% slopes GaB- Georgeville silty clay loam, 2 -6% slopes - GeB2- Georgeville silty clay loam, 2 -6% slopes GeC2- Georgeville silty clay loam, 6 -10% slopes NaB- Nanford -Badin complex, 2 -6% slopes NaC- Nanford -Badin complex, 6 -10% slopes Figure 5 Soils Map Maney Farm Stream Mitigation Site Cape Fear River Basin 03030002 Chatham County, NC r ( 1 AM FIn All .: ,`�1. .1.6.11/ 1.1.1.1./ PITPIT PIT PIT 7. ', 4 F+ 30�{ ♦ I t 6� PAP 'Q f r k• F F )•t t fit- , "4.., CO ■ I Project Location 71.Ir ' t Proposed Conservation Easement d Planted Buffer - ?; �r''♦ Stream Restoration ,�•.' ��'. •'yam -i. -�_ Stream Enhancement II 1�1. t.1..1.1.1.1. 1.1 .1.1•I 11 11 11 1 I.1 .1.1. = _ �erial • • •• .• hy witv,WILDLANDS E N G I N E E R I N G 0 325 Feet I I I Figure 6 Concept Map Maney Farm Stream Mitigation Site Cape Fear River Basin 03030002 Chatham County, NC