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Home My WebLink About20071531 Ver 1_Stone Ridge at Hayes Mountain (2)_20070910p 7- 1 5 3 1 StoneRidge at Hayes Mountain Stream and Wetland Mitigation Plan Buncombe County, North Carolina August 29, 2007 Prepared by: PO Box 882 Canton, NC 28716 Project Description The project site known as StoneRidge at Hayes Mountain is owned by SJH Enterprises, LLC, and is located off of Ridge Road near Enka, North Carolina. The site contains land in Buncombe County. Latitude and longitude for the site are 35.351247 N and 82.424428 W, respectively. The site is located within the Enka USGS Topo Quad. SJH Enterprises, LLC proposes to develop the property as a residential community on approximately 63.83 acres. Stream enhancement totaling 250 linear feet and wetland enhancement and littoral shelf establishment totaling 0.103 acre will be used as mitigation. The overall goal of the enhancement activities on site will be to provide a structurally stable hydrologic system where historic livestock activities have degraded the stream and wetland systems. The stream is a first order unnamed tributary to Pole Creek which drains to Hominy Creek then to the French Broad River. The stream has a 15 acre watershed. Enhancement Plan The developer of StoneRidge plans to enhance 250 linear feet of stream and 0.07 acre of wetland. The goals of the project are: 1. Stabilize banks and reduce erosion. 2. Create and preserve a riparian buffer with permanent native vegetation. 3. Create aquatic habitat and complexity. 4. Re-slope and stabilize banks around wetland. 5. Enhancement of wetland vegetation (to extend beyond current wetland). Construction Plan and Specifications Construction activities will include the systematic re-sloping of banks including bankful benches along the stream. The eroded banks surrounding the wetland will be re-sloped as well. A description of each treatment is described below. Re-slope Banks In areas where the banks can be re-sloped, this method will be used instead of toe armor. Vertical banks will be graded at a slope of 2:1 or flatter. Where appropriate, accessible bankfull benches will be established to reduce sheer stress on banks. Newly sloped banks will be graded into the existing stream banks. Any disturbed soil will be stabilized with erosion matting and planted with native vegetation. Existing mature trees will be preserved unless the stream bank erosion has damaged the tree. Monitoring Plan After construction completion, WNR staff will provide the resource agencies with a baseline monitoring report. Monitoring activities will take place every year for 5 years after construction completion. An annual monitoring report will be submitted each year following the monitoring activities. WNR will conduct monitoring and SJH Enterprises, LLC will provide the financial assurance that will ensure this project is complete and successful. An as-built report will be included with the first annual monitoring report. At least two bankfull events in separate years will be documented within 5-year monitoring period. If two bankfull events have not been documented, stream monitoring will continue until two bankfull events have occurred in two separate years. Success will be measured in terms of channel stability and plant survival. Problem areas identified in during any part of annual monitoring activities will be discussed with project partners. Any necessary remedial actions will be planned, approved, and implemented. Monitoring Parameters 1.0 Channel Stability 1.1 Cross Sections 1.2 Pebble Counts 2.0 Plant Survival 2.1 Monitoring Plots 3.0 Photographic Reference Sites 4.0 Biological Monitoring 1.0 Channel Stability Channel stability will be measured through the following two parameters: cross- sections and pebble counts; and then compared to previous measurements. Four permanent cross-sections will be set up on the stream representing 50% pools and 50% riffles. Pebble counts will be performed at each cross section. If there is substantial evidence of instability, such as down-cutting or erosion, remedial actions will be taken. 2.0 Plant Survival Vegetative success will be measured in terms of plant survival. Plant survival will be measured with stem counts in designated vegetative monitoring plots. Stem counts of at least 320 stems/acre in year 3 and 260 stems/acre in year 5 will be considered successful. Vegetative monitoring plots, 1/10 acre in size, will be set up adjacent to each cross section. Plant survivability will be assessed using these vegetative monitoring plots. If there is substantial plant mortality that leads to lowered stem counts, remedial actions will be taken. Areas with less than 75% vegetation coverage will be re-seeded and/or fertilized; and live stakes and bare rooted trees will be planted to achieve the desired densities. Exotic, invasive, and invader species will be removed so that they will not exceed 20% of the vegetative composition. 3.0 Photographic Reference Sites Photos will be taken at each cross section as well as other monumented reference sites throughout the stream reach. These photos will indicate aggradation, degradation, and/or bank erosion. If none exists, no remedial action will be required. If aggradation, degradation, and/or bank erosion occurs, the problem will be accessed and remedial actions will be planned, approved, and implemented. 4.0 Biological Monitoring Benthic macroinvertebrate sampling will be conducted before the project begins and will continue for at least three years of monitoring after project completion. Planting Plan and Specifications The objective will be to mimic most of the natural buffer that is on site, which is mainly composed of shrubs and trees. However, warm season grasses will be used, in accordance with the ~~Warm Season Grass Establishment and Management in North Carolina and Virginia" provided by the US Fish and Wildlife Service as a temporary planting to aid with soil stabilization. Recommended Native Species for Stream Restoration Trees Yellow Buckeye Aescu/us octandra Sweet Birch Betu/a /enta River Birch Betula nigra Bitternut Hickory Carya cordiformis Shagbark Hickory Carya ovata Persimmon Diospyros virginiana Green Ash Fraxinus pennsy/vanica Carolina Silverbell Ha/esia caro/iniana Blackgum Nyssa sy/vatica Sycamore P/atanus occidentalis Black Cherry Prunus serotina Black Willow Sa/ix nigra White Basswood Tilia heterphylla Small Trees and Shrubs Tag Alder A/pus serru/ata Serviceberry Ame/anchier arbrea Red Chokeberry Aronia arbutifolia Common Pawpaw Asimina triboba Sweet-shrub Calycanthus floridus Ironwood Carpinus caroliniana Alternate Leaf Dogwood Corpus a/ternifo/ia Silky Dogwood Corpus amomum Hazel-nut Cory/us Americana Witch Hazel Hamame/is virginiana Winter Berry I/ex verticillata Doghobble Leucothoe axil/cries Spicebush Lindera benzoin Male-berry Lyon/a /igustrina Umbrella Tree Magno/ia tripeta/a Ninebark Physocarpus opulifolius Wild Azalea Rhododendron peric/ymenoides Swamp Azalea Rhododendron viscosum Swamp Rose Rosa pa/ustris Silky Willow Sa/ix sericea Meadowsweet Spirea /atifolia Sweet Leaf Symplocos tinctoria Wihe-rod Viburnum cassinoides Yellow-root Xanthorhiza situp/icissima Herbaceous Jack-in-the-Pulpit Arisaema triphy//um Swamp M i I kweed Asc%pias incarnate Fringed Sedge Carex crinata Bladder Sedge Carex intumescens Hop Sedge Carex /upu/ina Lurid Sedge Carex /urida Broom Sedge Carex scoparia Tussock Sedge Carex stricta Fox Sedge Carex vu/pinoides Turtlehead Che%ne g/abra Umbrella Sedge Cyperus strigosus Bottlebrush Grass E/ymus hystrix Joe-Pye Weed Eupatorium fistu/osum Boneset Eupatorium pen`oliatum Jewelweed Impatiens capensis Soft Rush Juncus effuses Rice Cutgrass Leersia oryzoides Cardinal Flower Lobe/ia cardina/is Great Blue Lobelia Lobe/ia siphi/itica Seedbox Ludwigia a/ternifolia Switchgrass Panicum virgatum Tea rth u m b Polygonum sagittatum Green Bulrush Scirpus atrovirens Woolgrass Scirpus cyperinus Soft Stem Bulrush Scirpus va/idus Bur-reed Sparganium americanum March Fern Theypteris pa/ustris River Oats Uniola /atifolia Ironweed I/ernonia noveboracensis 7 ~- 1 5 3 1 ~;: ,' ... ~. ..~,. f~ ~~'~3~ ~ ~_.e, ,.~ ~ ,~. r4.,r.ra;:q ~yv. t ..i .. ~~ ~.'.•1 y ~ A S~ s a~ ' ~ r' . ,~ ',~,~~ ~ ~ ~ o~ fp -~ . 1m, I r. Photo 2. Eroded Banks and Poor Water Quality. a ~ ,` ~. ~~ ,. Photo 1. Cattle Impacted Stream. ~. a~' ~,. Photo 3. Lack of understory vegetation to stabilize stream banks. ,~. .t a ~,_ ~„'~~ Photo 4. Cattle Impacted Wetland. ,, r ~ - _ __ ~ '~ W amd -~nhancem n~ ~~~ ~~_ _ ,_ -- ,, . _, - -_- 0.07 Acne ~~, ,; l ~et~and` Littoral Shed ,,, ~_-- - _- ~- - ~:,0 . ~F~~cre ~~, t ~ ~~ ~~~ ~~_ ~, -_ ~~~~~~ ~ ,` ~ ~ .. ... ~ i ..- ~ -~.- ~~ ~ ~ ~i ,1 ~ ~~ ~~ i > ~ ~', ~I I ~ ~~ ~~' ,,~~ - ~ \ `• ~~i. --a_ - __~ / - -~- ~ ((/ ~St~ea r~n-€-~h~-~c~~e~t- ~, _ __ --_ ,, ,~~ 250 Line~r~eet~-_- --- __ _ - --- _-- Sh _ _ _ _ ------ --. ,, _ ~, \\\ \\ - ~ - ~,, ~, - ~~ ~ ., ~ _ Mitigation Required T e of Im act Amount LF or Acrea a Mitigation Ratio Based on Stream Multiplier Based on Im act Final Ratio Mitigation LF or Acrea e Dam & Culvert Pi e & Ri -Ra 88 1:1 Poor Qualit 1 for fill 1:1 88 Floodin 140 1:1 Poor Qualit 1 /2 for floodin .5:1 70 Pond & Culvert Pi e & Fill 0.03 1:1 Poor Qualit 1 for fill 1:1 0.03 Floodin 0.082 1:1 Poor Qualit 1/2 for floodin .5:1 0.041 Total Stream Impact 228 LF Total Wetland Impact 0.112 Acre Mitigation Proposed by Type Total 158 LF Total 0.071 Acre Type of Mitigation Method Ammount Proposed Multiplier SMU Stream Enhancement Level II On-Site 250 1.5 166.666667 Wetland Littoral Shelves On-Site 0.033 1 0.033 Wetland Enhancement On-Site 0.07 1.5 0.047 Total 167 LF Total 0.080 Acre Surplus 9 LF Surplus 0.009 Acre