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Home My WebLink AboutSpringdale Stream Restoration Report Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 1 of 8 Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 Prepared for West Springdale , LLC a SC LLC 910 Prestonwood Dr, Hartsville, SC 29550 Prepared by PR Engineering, PLLC, Preston R. Gregg, P.E. 83 Shermans Run, Canton, NC 28716 (828) 400-9353 | prengineering@outlook.com Figure 1: Westward View of Upper Tributary to Pigeon River Beginning of Project (February 15, 2022) Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 2 of 8 EXECUTIVE SUMMARY PR Engineering was contracted by West Springdale, LLC in February 2022 a>er the owner received a NoBce of ViolaBon from mulBple permiFng agencies. The project site was part of a larger common plan of development previously permiJed by another engineering firm. Site grading acBviBes exceeded the scope of the original permit. DevastaBng flooding associated with Tropical Storm Fred in August 2021 complicated maJers. Flood waters from TS Fred on the open graded site significantly changed stream morphology of the unnamed tributaries on the project site and obliterated the former onsite impoundment adjacent to Country Club Drive. PR Engineering was contracted to obtain proper Erosion Control and Related Permits and restore the onsite streams to the extent feasible harmonious with the intent of the development of the site. A>er mulBple design iteraBons and onsite meeBngs with Haywood County, NC DEQ, and USACE, PR Engineering has prepared a plan limiBng the stream impacts to the maximum extent feasible and restoring approximately 360LF of the upper Unnamed Tributary. The stream restoraBon plan follows the design guidelines as presented in “Stream RestoraBon – A Natural Channel Design Handbook” prepared by the North Carolina Stream RestoraBon InsBtute and North Carolina Sea Grant. The results of this effort are presented in brief in this report. As recommended in “Stream RestoraBon – A Natural Channel Design Handbook” and as widely accepted as the Best Management PracBce, preference for the restoraBon stream design is based on a nearby reference reach. The reference reach is an offsite porBon of the UT to East Fork Pigeon River. The reference reach is located NE of the exisBng wetland on the “George Property.” (LaBtude 35.443, Longitude -82.808). Figure 2: Project Site and Reference Reach LocaHon PROJECT SITE REFERENCE REACH Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 3 of 8 Figure 3: Reference Reach, Looking Eastward (upstream) Figure 4: Reference Reach, Looking Westward (downstream) Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 4 of 8 PROJECT DESCRIPTION The project site is located within Springdale Golf Course, a recreaBonal and residenBal development. The stream restoraBon iniBaBve is part of a larger proposed project to expand the exisBng golf driving range already onsite. The primary land use is recreaBonal. The UT targeted for restoraBon is an Rosgen Stream Type A5. The need for restoraBon is plainly evident by the incising that is already occurring along the upper porBon of the stream. The design takes a Rosgen Priority II approach by creaBng a new, stable stream at the exisBng channel bed elevaBon. WATERSHED CHARACTERIZATION The drainage area of the project reach at the upstream limits is 8.7 acres. Soil types are Group B hydrologic soils Evard-Cowee complex (EvD) and Saunook loam (ScB). Storm Event Runoff (cfs) Notes 2-yr 6.5 Bank full flow 10-yr 13.4 50-yr 22.1 Carried by 36” culvert downstream Table 1 Figure 5: ExisHng Soils Map (NRCS), Haywood County GIS Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 5 of 8 REFERENCE REACH ANLYSIS A reference reach is a channel with a stable dimension, paJern, and profile within a parBcular valley morphology. The reference reach is used to develop dimensionless morphological raBos (based on bankfull stage) that can be extrapolated to disturbed/unstable streams to restore a stream of the same type and disposiBon as the reference stream (Rosgen, 1998). The selecBon criteria for a reference reach includes a stable reach occurring under similar hydrophysiographic, landform, and watershed land use condiBons. The reference reach for this project is an offsite porBon of the UT to East Fork Pigeon River. The reference reach is located NE of the exisBng wetland on the “George Property.” (LaBtude 35.443, Longitude -82.808). The selecBon of this reference reach was based on: locaBon in the same hydrophysiographic province, similar valley morphology, similar longitudinal slope, and similar sediment profiles as the project site. Field assessments and GIS analysis were employed to determine the parameters of the reference reach. The sinuosity of the reference reach was determined from GIS analysis and confirmed with field measurements. Field measurements also recorded the reference reach pool-riffle system consisBng of 1-foot elevaBon drops in steep areas and 2-3” drops in others. Figure 6: Riffle-Pool Complex, Reference Reach RESTORATION DESIGN The restoraBon design is based on a Priority Level II approach as described in “A Geomophological Approach to RestoraBon of Incised Rivers,” (Rosgen, 1997). The exisBng stream flow will be diverted through a temporary channel while the new channel is constructed. The design proposes construcBng approximately 360 linear feet of restored channel. The proposed stream dimension, paJern, and profile will be based on the detailed morphological criteria and hydraulic geometry relaBonships developed from the reference stream (Table 2, below). Refer to the plan set for proposed longitudinal stream slope profile, cross-secBons of Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 6 of 8 the proposed stream channel realignment, pool-riffle structures, and other necessary details. Cross-secBon details of the proposed stream include cross-secBonal area, boJom width, top width, streambank slopes, and channel depth. Pool-riffle complexes that match that of the reference reach and natural character of the stream are included in the design. Rock cross-vanes with an elevaBon drop of 1’ are used in the steepest porBons of the stream to stabilize the restored channel by reducing stress and maintaining the established streambed morphology. Cobbles secBons with an elevaBon change of 2-3” are used in areas where the longitudinal slope is less than 10-percent. Coir fiber maFng will be used to provide temporary stabilizaBon on newly graded streambanks. Future channel aggradaBon and/or degradaBon has been considered. Parameter Exis+ng Stream Reference Reach Design Stream Bankfull XSEC area, Aw (sq >) 0.675 2.23 0.94 Bankfull width, Wbkf (>) 1.35 4 2.5 Bankfull mean depth, Dbkf (>) 0.5 0.56 0.5 Width-to-depth raBo, Wbkf/Dbkf 2.7 7.14 5 Width flood-prone area, Wfpa (>) 29 14.5 Entrenchment raBo, Wfpa/Wbkf 7.25 5.8 Bankfull Velocity, Vbkf 6.8 7.2 Bankfull Discharge, Qbkf 4.4 15.1 6.8 Max depth @ bkf, Dmax (>) 0.583 0.5 Max depth raBo, Dmax/Dbkf 1.04 1 Bank height, Dtob (>) 0.56 Bank height raBo (BHR), Dtob/Dmax 0.96 Meander length, Lm (>) 311 156 Meander length raBo (BHR), Lm/Wbkf 78 Radius of curvature, Rc (>) 99 50 Radius of curvature raBo, Rc/Wbkf 25 Belt width, Wblt (>) 53 26 Meander width raBo, Wblt/Wbkf 13 Sinuosity, K 1.1 1.1 Va lley slope, Sval (>/>) 0.09 0.1 Channel slope, Save (>/>) 0.09 0.1 Riffle length, Lrif (>) 7.5 4 Riffle length raBo, Lrif/Wbkf 1.9 Pool max depth, Dpool (>) 1.1 1 Pool max depth raBo, Dpool/Dbkf 2 Pool area, Apool (sq >) 4.2 1.75 Pool area raBo, Apool/Abkf 1.9 Pool width, Wpool (>) 3.83 2 FR O M F I E L D FR O M GI S MA P P I N G Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 7 of 8 Pool width raBo, Wpool/Wbkf 1 Pool length, Lpool (>) 2.1 1.06 Pool length raBo, Lpool/Wbkf 0.53 Pool-pool spacing, p-p (>) 7.5 4 Pool-pool spacing raBo, p-p/Wbkf 1.9 Table 2 RIPARIAN BUFFER NaBve woody and herbaceous species will be used to establish riparian buffers on both sides of the restored reach. Landscaping details and notes are provided within the plan set. Herbaceous vegetaBon within the buffer shall consist of a naBve grass mix that may include: Big bluestem, Bushuy Bluestem, Splitbeard bluestem, Broomsedge, Wiregrass, River cane/switch cane, Pennsylvania sedge, Plantain-leaved sedge, River Oats, Poverty Oatgrass, Oat grass, Crinkled Hairgrass, BoJle brush, Purple Love grass, Pink Muhly grass, Switch grass, LiJle bluestem, Indian grass, Eastern gammagrass. Woody live stakes shall be Silky Dogwood, Black Willow, and Elderberry. The success of the riparian buffer planBngs will be evaluated regularly and no less than annually for a minimum of two years or unBl the stream has become permanently re-established but no more than 5 years following project compleBon.. Riparian vegetaBon must meet a minimum survival success rate of 80% across the project area. If monitoring indicates that the survival rate is not being met, appropriate correcBve acBons will be developed, to include invasive species control, the removal of dead/dying plants and replanBng. MONITORING AND EVALUATION Monitoring shall consist of the observaBon and analysis of stream stability and riparian/stream bank vegetaBon survivability data to support the evaluaBon of the project in meeBng established restoraBon objecBves. Specifically, project success will be assessed uBlizing field observaBons of stream dimensions, paJern, and profile, structure evaluaBon, site photographs, and vegetaBon survival rate assessment. The first scheduled monitoring will be conducted at the end of the first full growing season following project compleBon. Monitoring shall subsequently be conducted annually unBl the stream for a minimum of two years or unBl the stream has become permanently re-established but no more than 5 years following project compleBon. Take photographs throughout the monitoring period at the same locaBons. Include both upstream and downstream views. Compare to photos from previous years to evaluate vegetaBve growth and channel stability. Use photographs to subjecBvely evaluate channel aggradaBon or degradaBon, bank erosion, success of riparian vegetaBon and effecBveness of in- Stream Restora+on Design as part of Springdale Golf Course Driving Range Expansion Cruso, Haywood County, North Carolina February 20, 2023 | Page 8 of 8 stream structures and erosion control measures. Photos will indicate the presence or absence of developing bars within the channel or an excessive alteraBon in channel depth or width. Photos also will indicate the presence of any excessive bank erosion or conBnuing degradaBon of the bank. The series of photos over Bme should indicate successional maturaBon of riparian vegetaBon. Monitoring reports will be prepared and retained by the owner a>er all monitoring tasks for each monitoring event are completed. Each report must be made available to the appropriate permiFng agency upon request unBl a>er 5 years following project compleBon. Each report will include observed cross secBon and profile data, photographs, vegetaBon assessment, and other informaBon as necessary. Any significant deviaBons from the as- built survey and previous annual measurements, as well as evaluaBons as to whether the changes indicate a stabilizing or de-stabilizing condiBon, must be reported to the Engineer and the appropriate permiFng agency in order to develop a correcBve acBon plan.