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HomeMy WebLinkAboutSW1210602_Design Calculations_20210630DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 SUPPORTING CALCULATIONS FOR Suncap Post Construction Stormwater Management — Supporting Documentation TOWN OF MILLS RIVER HENDERSON COUNTY, NORTH CAROLINA PREPARED BY: WGLA Engineering, PLLC CONSULTING ENGINEERS 724 5t" Avenue West Hendersonville, NC 28739 P-1342 June 2021 DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Town of Mills River Henderson County, North Carolina Table of Contents Narrative and Project Description Location Map and Site Plans NOAA Rainfall Data Geotechnical Report Stormwater Collection System Bioretention Cell Supplement Level Spreader Design Calculations DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Narrative and Project Description DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Town of Mills River Henderson County, North Carolina Erosion Control Narrative and Project Description: Site Location: This site is located in Henderson County and is bounded by Ferncliff Park Drive (S.R. 2418) to the south, vacant wooded parcel to the north and west and a newly constructed gravel road by NCDOT to the east. The site is accessed from NC 280 by Ferncliff Park Drive. Project Description: Suncap is a project involving the construction of a new distribution facility in the Ferncliff Industrial Park. Stormwater from the parking, drive isles, loading areas and building will be collected and directed to five bio-retention cells located around the perimeter of the site. Site Description: The site is located north of Ferncliff Park Drive (S.R. 2418), west of GF Linamar facility and east and south of vacant wooded parcels. Streams and wetlands on and in the vicinity of the site have been verified by the Corps of Engineers. No impacts to streams or wetlands are planned on this parcel as part of the construction of the distribution facility site. The bioretention cells will be located along the perimeter the site to collect and treat stormwater runoff. Soils information has been collected for these areas, and the proposed cell will be more than 2' above the seasonal high water table. No borings on the entire site encountered groundwater, and the bore levels were far below the proposed facility or any of the bioretention cells. A copy of the geotechnical report is included in this package. The bioretention cells will be sized to accommodate all the impervious area of this site. Three feet of soil media will be provided in the basins, and the basins will be covered with mulch. The basins will also be constructed with forebays to reduce inlet velocity and to collect any trash or sediment from the impervious area. Liners are being provided for bioretention cells A, B and C, due to the proximity to retaining walls, steep slopes or other features. The liner is required to prevent infiltration of water to areas that could cause damage or failures. LEED: The Owner has elected to meet LEED requirements for this project related to stormwater management. Follow is a summary of the strategies used to meet the stormwater requirements: SSc6.1 Stormwater Design — Quantity Control The Suncap site is greater than 50% impervious (53%) for this development. Calculations have been provided showing the post -development runoff rates and quantities for the 90' percentile storm events (1.25 inches). The quantity is controlled with the BMPs described above. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 The routing of storm events through the SCM was performed using Hydroflow to generate hydrographs and to calculate runoff rates. SSc6.2 Stormwater Design — Quality Control Removal of total suspended solids for the GF Linamar site is accomplished through the use of stormwater BMPs used. Five proposed bioretention cells have been provided to treat runoff from parking, buildings, loading and drive areas. Calculations for the water quality volumes required and provided in the bioretention cells have been provided with this report. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Location Map and Site Plans DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 41 A. 1 Ijf � IFS ✓ ��' � :. 1 � • / VVILLE REG AIRPORT j � I _ ,3 �- h r •`f Ilan _�, t i �I 65 . � ,s UFe 19 i -'J 1L C 1 � V ry '• � �� 'J _ 1 �� � l� � � 00 1 ` Q �JI�f � 2a50 �'� l ..�'. ^ • ��• tl ,�� Preliminary � • •� ii+� � • •ur "• 1NI � � � � � 111�^ WGLA ENGINEERING, PLLC 724 5th AVENUE Suncap Skyland Quad Map HENDERSONVILLE, NC 28739 Town of Mills River (828) 687-7177 Henderson County Job #: 20176 WGLA.COM North Carolina Date: 6/22/21 NC LICENSE P-1342 Scale: 1" = 2000' DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 1310—RETENTION CELL "B" 1310—RETENTION CELL "A" I I I I I V I 1310—RETENTION CELL "E" DRAINAGE AREAS DRAINAGE TO BIO-CELL DRAINAGE TO BIO-CELL DRAINAGE TO BIO-CELL DRAINAGE TO BIO-CELL DRAINAGE TO BIO-CELL "B" "C» 11 D" „E„ 1310—RETENTION CELL "C" 1310—RETENTION CELL "D" RNCLIFF PARK DRIVE (PUBLIC 60' R/W) Preliminary WGLA ENGINEERING, PLLC Stormwater WGLA 724 5th AVENUE Suncap Management Plan HENDERSONVILLE, NC 28739 Town of Mills River Sheet 1 of 1 (828) 687-7177 Henderson County Job #: 20176 Engineering WGLA.COM North Carolina Date: 6/22/21 NC LICENSE P-1342 Scale: 1' = 300' DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap NOAA Rainfall Data DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 NOAA Atlas 14, Volume 2, Version 3 ASHEVILLE WSO AP Station ID: 31-0300 Location name: Fletcher, North Carolina, USA* Latitude: 35.4358*, Longitude:-82.5392° Elevation: Elevation (station metadata): 2140 ft** 9 M" *source: ESRI Maps source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland PF tabular I PF graphical I Maps & aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Duration Average recurrence interval (years) 1 ���������� 2 5 10 25 50 100 200 500 1000 0.365 0.435 0.521 0.587 0.673 0.738 0.804 0.870 0.955 1.02 5-min (0.329-0.406) (0.393-0.483) (0.470-0.579) (0.527-0.651) (0.600-0.745) (0.655-0.816) (0.710-0.891) (0.763-0.966) (0.827-1.07) (0.878-1.15) 0.584 0.695 0.835 0.939 1.07 1.18 1.28 1.38 1.51 1.61 1 0-min (0.526-0.649) (0.628-0.772) (0.752-0.928) 1 (0.843-1.04) 1 (0.956-1.19) 11 (1.04-1.30) 11 (1.13-1.42) 1 (1.21-1.53) 11 (1.31-1.69) 11 (1.38-1.81) 0.729 0.874 1.06 1.19 1.36 1.49 1.62 1.74 1.90 2.02 1 5-min (0.657-0.811) (0.789-0.971) (0.951-1.17) 1 (1.07-1.32) 1 (1.21-1.50) 11 (1.32-1.65) 11 (1.43-1.79) 1 (1.53-1.93) (1.65-2.13) (1.74-2.28) 1.00 1.21 1.50 1.72 2.01 2.24 2.47 2.71 3.03 3.28 30-min (0.901-1.11) (1.09-1.34) 11 (1.35-1.67) 1 (1.80-2.23) 11 (1.99-2.48) 11 (2.18-2.74) 1 (2.37-3.01) (2.62-3.38) (2.81-3.69) 1.25 1.51 1.92 2.24 2.68 3.04 3.41 3.80 4.34 4.79 60-min (1.12-1.39) 11 (1.37-1.68) (1.73-2.14) 1 (2.39-2.97) 11 (2.69-3.36) 11 (3.01-3.78) 1 (3.33-4.22) (3.76-4.85) (4.10-5.38) 1.46 1.77 7 7 2.24 2.60 3.13 7 3.55 F 3.99 F 4.47 5.13 5.67 2-hr (1.31-1.62) 11 (1.59-1.96) (2.00-2.47) 1 (2.33-2.88) 1 (2.77-3.47) 11 (3.13-3.93) 11 (3.49-4.43) 1 (3.88-4.96) (4.39-5.73) (4.81-6.37) 1.56 1.88 2.36 F 3.33 7 3.80 F 4.31 F 4.86 5.65 6.30 3-hr (1.41-1.75) 11 (1.70-2.10) 11 (2.12-2.62) 1 (2.95-3.70) 11 (3.35-4.23) 11 (3.76-4.79) 1 (4.19-5.41) (4.80-6.34) (5.29-7.11) 1.95 2.32 2.86 3.32 3.99 4.56 5.18 5.85 6.82 7.64 6-hr (1.78-2.14) 11 (2.11-2.55) 11 (2.60-3.14) 1 (3.01-3.65) 1 (3.59-4.38) 11 (4.07-5.00) 11 (4.57-5.69) 1 (5.11-6.44) (5.86-7.56) (6.48-8.52) 2.46 2.93 3.59 4.12 4.87 5.47 6.09 6.74 7.65 8.36 12-hr (2 26-2.68) 11 (2.69-3.20) 11 (3.30-3.92) 1 (4.44-5.31) 11 (4.97-5.97) 11 (5.50-6.66) 1 (6.05-7.40) (6.78-8.45) (7.34-9.31) 2.91 3.49 4.29 4.94 5.82 6.54 7.28 8.05 9.12 9.97 24-hr (269-3.15) 11 (3.24-3.79) 11 (3.97-4.66) 1 (4.56-5.34) 1 (5.36-6.30) 11 (6.00-7.07) 11 (6.65-7.86) 1 (7.31-8.70) (8.21-9.87) 11 (8.90-10.8) 3.46 4.13 5.03 5.75 6.74 7.54 8.36 9.20 10.4 11.3 2-da (3.22-3.73) 11 (3.84-4.45) 11 (4.67-5.42) 1 (6.23-7.25) 11 (6.94-8.11) 11 (7.67-9.00) 1 (8.40-9.93) (9.39-11.2) (10.2-12.2) 3.69 4.39 5.32 6.04 7.03 7.82 8.62 9.44 10.6 11.4 3-da (3.44-3.96) 11 (4.10-4.72) 11 (4.95-5.71) 1 (5.62-6.48) 1 (6.52-7.54) 11 (7.22-8.39) 11 (7.93-9.27) 1 (8.65-10.2) (9.60-11.4) (10.3-12.4) 3.92 4.67 5.60 6.34 7.33 8.10 8.89 9.68 10.7 11.6 4-da (3.66-4.19) (4.35-5.00) (5.22-5.99) (5.90-6.78) (6.80-7.84) (7.50-8.67) 11 (8.20-9.53) 1 (8.90-10.4) (9.81-11.6) (10.5-12.5) 4.57 5.42 6.50 7.36 8.52 9.44 10.4 11.3 12.6 13.7 7-da (4.27-4.89) (5.07-5.82) (6.07-6.97) (6.86-7.88) (7.92-9.11) (8.75-10.1) 11 (9.59-11.1) 1 (10.4-12.1) (11.5-13.6) (12.4-14.7) 5.23 6.19 7.34 8.25 9.49 10.5 11.4 12.4 13.8 14.8 10tlay (4.93-5.56) (5.83-6.58) (6.92-7.81) (7.77-8.77) (8.90-10.1) (9.79-11.1) 11 (10.7-12.2) 1 (11.6-13.2) (12.7-14.7) 11 (13.6-15.9) 7.11 8.36 9.71 10.8 12.1 13.2 14.2 15.1 16.4 17.4 20tlay (6.72-7.51) (7.91-8.84) (9.18-10.3) (10.2-11.4) (11.4-12.8) (12.4-13.9) 11 (13.3-15.0) 1 (14.2-16.0) (15.3-17.4) (16.1-18.5) 8.72 10.2 11.7 12.8 14.2 15.3 16.2 17.2 18.3 19.1 30tlay (8.28-9.20) (9.72-10.8) (11.1-12.3) (12.2-13.5) (13.5-15.0) (14.4-16.1) 11 (15.3-17.1) 1 (16.2-18.1) (17.2-19.4) (17.9-20.3) 11.1 13.0 14.6 15.8 17.3 18.3 19.2 20.1 21.1 21.8 45tlay (10.6-11.6) (12.3-13.6) (13.9-15.3) (15.0-16.6) (16.4-18.1) (17.4-19.2) 11 (18.2-20.2) 1 (19.0-21.1) (20.0-22.2) (20.6-23.0) 13.3 15.5 17.3 18.6 20.2 21.3 22.3 23.2 24.2 24.9 60tlay (12.7-14.0) (14.8-16.3) (16.5-18.2) (17.819.6) (19.2-21.3) (20.2-22.4) (21.2-23.5) (22.0-24.4) (22.9-25.6) (23.5-26.3) Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 NOAA Atlas 14, Volume 2, Version 3 Location name: Fletcher, North Carolina, USA* �'It Latitude: 35.4358*, Longitude:-82.5392* Elevation: 2147.72 ft * *source: ESRI Maps 'w,�w, source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland PF tabular I PF graphical I Maps & aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches/hourp Average recurrence interval (years) 1 2 5 10 25 501 100 200 500 1 000 4.38 5.22 6.25 7.04 8.08 8.86 9.65 10.4 11.5 12.3 5-min (3.95-4.87) 1 (4.72-5.80) 11 (5.64-6.95) 11 (6.32-7.81) 1 (7.20-8.94) 1 (7.86-9.79) 11 (8.52-10.7) 1 (9.16-11.6) 1 (9.92-12.8) 11 (10.5-13.8) 3.50 4.17 5.01 5.63 6.43 7.06 7.67 8.27 9.07 9.68 10-min (3.16-3.89) (3.77-4.63) (4.51-5.57) (5.06-6.24) (5.74-7.12) (6.26-7.80) (6.77-8.50) (7.25-9.19) (7.85-10.1) (8.30-10.9) 2.92 3.50 4.22 4.75 5.44 5.96 6.46 6.96 7.61 8.10 15-min (2.63-3.24) (3.16-3.88) (3.80-4.70) (4.27-5.26) (4.85-6.02) (5.28-6.58) (5.70-7.16) (6.10-7.73) (6.59-8.50) (6.94-9.10) 2.00 2.41 3.00 3.44 4.03 4.48 7 7 4.95 5.42 6.05 6.56 30-min (1.80-2.22) 1 (2.18-2.68) 11 (2.70-3.34) 11 (3.09-3.81) 1 (3.59-4.46) 1 (3.98-4.96) 11 (4.37-5.48) 1 (4.75-6.02) 1 (5.24-6.77) 11 (5.62-7.37) 1.25 1.51 1.92 2.24 2.68 3.04 3.41 3.80 4.34 4.79 60-min (1.12-1.39) 1 (1.37-1.68) 11 (1.73-2.14) 11 (2.01-2.48) 1 (2.39-2.97) 1 (2.69-3.36) 11 (3.01-3.78) (3.33-4.22) (3.76-4.85) (4.10-5.38) 0.729 0.885 1.12 1.30 1.56 1.77 2.00 2.23 2.56 2.83 2-hr (0.655-0.809) (0.796-0.980) (1.00-1.24) 11 (1.16-1.44) 1 (1.39-1.73) 1 (1.56-1.97) 11 (1.75-2.22) (1.94-2.48) (2.20-2.86) (2.40-3.18) 0.520 0.626 0.786 0.916 1.11 1.26 1.43 1.62 1.88 2.10 3-hr (0.469-0.581) (0.564-0.698) (0.706-0.873) (0.820-1.02) (0.982-1.23) 1 (1.11-1.41) 11 (1.25-1.60) 1 (1.40-1.80) 1 (1.60-2.11) 11 (1.76-2.37) 0.325 0.387 0.477 0.554 0.666 0.761 0.864 0.976 1.14 1.27 6-hr (0.297-0.358) (0.353-0.425) (0.435-0.524) (0.503-0.609) (0.600-0.732) (0.680-0.835) (0.764-0.951) (0.853-1.08) (0.978-1.26) 11 (1.08-1.42) 0.204 0.243 0.298 0.342 0.404 0.454 0.506 0.560 0.635 0.694 12-hr (0.188-0.223) (0.223-0.265) (0.274-0.325) (0.314-0.373) (0.368-0.440) (0.412-0.496) (0.457-0.553) (0.502-0.614) (0.563-0.702) (0.609-0.773) 0.121 0.145 0.179 0.206 0.243 0.273 0.303 0.335 0.380 0.415 24-hr (0.112-0.131) (0.135-0.158) (0.166-0.194) (0.190-0.223) (0.223-0.262) (0.250-0.295) (0.277-0.328) (0.305-0.362) (0.342-0.411) (0.371-0.450) 0.072 0.086 0.105 0.120 0.140 0.157 0.174 0.192 0.216 0.235 2{iay (0.067-0.078) (0.080-0.093) (0.097-0.113) (0.111-0.129) (0.130-0.151) (0.145-0.169) (0.160-0.188) (0.175-0.207) (0.196-0.234) (0.212-0.255) 0.051 0.061 0.074 0.084 0.098 0.109 0.120 0.131 0.147 0.159 3{iay (0.048-0.055) (0.057-0.066) (0.069-0.079) (0.078-0.090) (0.091-0.105) (0.100-0.117) (0.110-0.129) (0.120-0.141) (0.133-0.158) (0.144-0.172) 0.041 0.049 0.058 0.066 0.076 0.084 0.093 0.101 0.112 0.121 4{iay (0.038-0.044) (0.045-0.052) (0.054-0.062) (0.061-0.071) (0.071-0.082) (0.078-0.090) (0.085-0.099) (0.093-0.108) (0.102-0.120) (0.110-0.130) 0.027 0.032 0.039 0.044 0.051 0.056 0.062 0.067 0.075 0.081 7{iay (0.025-0.029) (0.030-0.035) (0.036-0.041) (0.041-0.047) (0.047-0.054) (0.052-0.060) (0.057-0.066) (0.062-0.072) (0.069-0.081) (0.074-0.088) 0.022 0.026 0.031 0.034 0.040 0.044 0.048 0.052 0.057 0.062 10-da (0.021-0.023) (0.024-0.027) (0.029-0.033) (0.032-0.037) (0.037-0.042) (0.041-0.046) (0.044-0.051) (0.048-0.055) (0.053-0.061) (0.057-0.066) 0.015 0.017 0.020 0.022 0.025 0.027 0.030 0.032 0.034 0.036 20-da (0.014-0.016) (0.016-0.018) (0.019-0.021) (0.021-0.024) (0.024-0.027) (0.026-0.029) (0.028-0.031) (0.030-0.033) (0.032-0.036) (0.034-0.038) 0.012 0.014 0.016 0.018 0.020 0.021 0.023 0.024 0.025 0.027 30-da (0.011-0.013) (0.013-0.015) (0.015-0.017) (0.017-0.019) (0.019-0.021) (0.020-0.022) (0.021-0.024) (0.022-0.025) (0.024-0.027) (0.025-0.028) 0.010 0.012 0.014 0.015 0.016 0.017 0.018 0.019 0.020 0.020 45-da (0.010-0.011) (0.011-0.013) (0.013-0.014) (0.014-0.015) (0.015-0.017) (0.016-0.018) (0.017-0.019) (0.018-0.020) (0.018-0.021) (0.019-0.021) 0.009 0.011 0.012 0.013 0.014 0.015 0.015 0.016 0.017 0.017 60-da (0.009 0.010) (0.010 0.011) (0.011 0.013) (0.012-0.014) (0.013-0.015) (0.014-0.016) (0.015-0.016) (0.015-0.01-1) (0.016-0.018) (0.016-0.018) Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Geotechnical Report DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 N ❑ VA March 12, 2021 SUNCAP PROPERTYGRouP 6101 Carnegie Boulevard, Suite 180 Charlotte, North Carolina 28209 Attention: Mr. Van Boyett Development Associate Subject: Seasonal High Water Table Determination FernclifF Property Fletcher, North Carolina NOVA Project Number 10705-2021005 Dear Mr. Boyett: We have completed the requested Seasonal High Groundwater Table (SHWT) Determinations for the above referenced project. For this determination we have teamed with Three Oaks Engineering. The field investigation for this study was completed on March 7, 2021 and consisted of five (5) hand auger borings for SHWT determinations within four (4) stormwater control measures (SCMs). The SHWT borings were advanced to a target depth of approximately five (5) feet below the existing grades; however, some borings were advanced deeper. Readings SHWT-1 and SHWT-4 did not reach the proposed target depth (5') due to auger refusal (rock) at 59" and 51" below ground surface, respectively. The attached report, prepared by Three Oaks Engineering, contains the results of the field exploration. To summarize, soil characteristics indicative of a SHWT (Hayesville Soil Series) were not observed in any of the five (5) borings performed within the four (4) SCMs during the investigation. The attached report should be reviewed for additional details and information regarding testing procedures, locations, and results. We appreciate the opportunity to continue to be of service on this project. Please contact us if you have any questions or if we may be of further assistance. Sincerely, NOVA Engineering and Environmental, Inc. k"--- A—� Kyle Russell avid E. Perialva, P.E. Staff Professional Senior Project Manager PROFESSIONAL I PRACTICAL I PROVEN 417 Minuet Lane, Suite D, Charlotte, North Carolina 28217 NOVA North Carolina License No: C-2807 t. 980.321.4100 / f. 980.321.4099 / usanova.com DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 SEASONAL HIGH WATER TABLE DETERMINATION Ferncliff Henderson County, North Carolina Three Oaks Job 921-741 Prepared For: NOVA 417 Minuet Lane, Suite D Charlotte, NC 28217 Prepared By: 324 Blackwell Street, Suite 1200 Durham, NC 27701 (919) 732-1300 March 11, 2021 solk M4 LA Evan T. Morgan,�� DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 INTRODUCTION NOVA is investigating the construction of four (4) stormwater control measures (SCMs) within the Ferncliff project site located at the end of Ferncliff Park Drive in Fletcher, Henderson County, NC. The SCMs are being considered to collect and treat runoff from impervious surfaces. As part of the application process, a soils investigation detailing soil type and depth to the seasonal high water table (SHWT) at five (5) locations is required. Three Oaks Engineering (Three Oaks) has been retained to perform the soil investigation. INVESTIGATION METHODOLOGY The Web Soil Survey was referenced prior to the field investigation to get an overview of the possible soil series located at the SCM location. The Hayesville soil series is mapped at the proposed SCM locations (Figure 1). Information for these series is listed in Table 1. Table 1. Map Unit Symbol, Soil Series and Taxonomic Classification Map Unit Symbol Soil Series Taxonomic Class H C Hayesville Fine, kaolinitic, mesic Typic Kanhapludults H E The field investigation was performed on March 7, 2021, by Evan T. Morgan, LSS utilizing a hand - turned auger. The boring locations were staked with a target depth of 5-feet. The site was wooded. Observations of the landscape (slope, drainage patterns, etc.) as well as soil properties (depth, texture, structure, color, seasonal wetness, restrictive horizons, etc.) were recorded. Soil profiles were described per the USDA-NRCS, Field Book for Describing and Sampling Soils, version 3.0. Soil color was determined with a Munsell Soil Color Chart. RESULTS A soil series determination was made by comparing the soil boring profile description to the NRCS Official Series Description (OSD) and the results listed in Table 2. A SHWT was not observed at any of the boring locations. The target depth was not achieved at boring SHWT-1 (59") and SHWT-4 (51") due to auger refusal from subsurface rock. All soil borings were representative of the Hayesville soil series. Full soil profile descriptions and a key to profile abbreviations are attached. The NRCS OSD for the Hayesville soil series is appended. Table 2. Soil Series Determination and SHWT Depth Soil Boring Soil Series Determination SHWT in. below surface) SHWT-1 Hayesville >59 SHWT-2 Hayesville >90 SHWT-3 Hayesville >98 SHWT-4 Hayesville >51 SHWT-5 Hayesville >92 Ferncliff SHWT March 11, 2021 Three Oaks Job #21-741 1 DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 CONCLUSIONS The findings presented herein represent Three Oaks' professional opinion based on our soil investigation. A SHWT was not observed at any of the borings. The target depth of 5-feet was not achieved at SHWT-1 and SHWT-4 due to shallower auger refusal. Due to the inherent variability of soils to change over short distances, the soil profile description presented in this report may not be representative of the entire soil system of the SCM footprint. This report is provided to assist in the application for the SCMs by providing the soil information. The permitting agency must issue the final permit. Any concurrence with the findings in this report would be made at that time. Ferncliff SHWT March 11, 2021 Three Oaks Job #21-741 2 DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 SHWT Determination Ferncliff Henderson County, North Carolina Date: March 2021 Scale: 0 80 160 Feet I I I ,lob No.: 21-741 Drawn By: ETM Checked By: MGW Figure DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 S+" Slaw SRC SOIL EVALUATION FORM Three Oaks Engineering Job: Z( N fiffmi-I p S�.Ir,,,+ 324 Blackwell Street, Suite 1200 County: d."., Durham, NC 27701 Date: 3 ]-ZI 919.732.1300 Sheet: I of Z-� o or o s Structure / Consistence / Matrix Texture Mineralogy Color R /so x l,s 3 3 Mottle Colors (Quantity, Size, Contrast, Color) E i L L fi s ,'P / tL o IMsr /c F.� /5P V A v �G H 4 /G �/63, S/' G ri SG I IFA / 0 0 (o A, IS m ? !a 811 Nv Si I wpm Szr'' r f•E q ►1 S Z n6- 51 7. 3y t ' / '1a 'L VM _'Ib i A r r t,rr i IM&A All FK f 5a d to Y/3 Zo �►S6t L Fr-S 4 2!r1 �S`l-' 7►5 GL V4ASS S 7 S Rs F 7.S P I w 611 n Of Evaluated by: E. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 50t' 5t-�-T SOIL EVALUATION FORM Three Oaks Engineering 324 Blackwell Street, Suite 1200 Durham, NC 27701 919.732.1300 Job: Zl-7Nl rCr) C(%&' SFIET County: 9Cijf1e- ,j Date: 3,7-z f Sheet: L of Z b 'o = as O = �o Structure/ Texture Consistence/ Mineralogy Matrix Color Mottle Colors (Quantity, Size, Contrast, Color) If5, 5P -r 1-4 3�9 to S-1 A 0 Tyk 5-1Y tl Imp S.tL Fk 1f P to W ► a z., 51 Om S,`G Sty Id SA 3 VRk. /S'to 1C'YRt 10 /S P �T-nvf -I If 7ram"+ % G F.L f SS,SP 7,7n-VA k, 2(o 171- 1 !�-Sp 951ed c 10 k. 1 ' t 0 61 40 001 �'� F/L 7 r M- Z p �•� CAM S L URL 4L-T Evaluated by: DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Key to Abbreviations for Soil Profile Descriptions DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 HORIZON AND LAYER DESIGNATIONS Use capital letters to identify master horizons; e.g., A, B. Use suffixes (lowercase letters) to denote additional horizon characteristics or features; e.g., Ap, 6tA. (For more detailed criteria see the "Soil Taxonomy" section [p. 4-1]; for complete definitions, see Keys to Soil Taxonomy [Soil Survey Staff, 2010].) Label a horizon (assign horizon designation) only after all morphology is recorded, MASTER AND TRANSITIONAL HORIZONS AND LAYERS' — Identify the master horizons of the soil profile. Horizon Criteria (expanded details listed in "Soil Taxonomy" section) O Organic sail materials (not limnic). A Mineral; organic matter (humus) accumulation, loss of Fe, AI, clay. AB or AE Dominantly A horizon characteristics but also or AC Contains some B, E, or C horizon attributes. A/B or A/E Discrete, intermingled bodies ofA and B, E, or C or A/C material; majority is A material. E Mineral; some loss of Fe, Al, clay, or organic matter. EA Dominantly E horizon characteristics but also or EB Contains some A, B, or C horizon attributes. or EC E/A Discrete, intermingled bodies of E and A or B horizon or E/B material; majority of horizon is E material. E and Bt Thin, heavier textured lamellae (Bt) within a B and E dominantly E horizon (or thin E within dominantly B horizon). BA or BE Dominantly B characteristics but contains A, E, or C or BC horizon attributes. B/A or B/E Discrete, intermingled bodies of B and A, E, or C Or B/C material; majority of horizon is B material. Subsurface accumulation of clay, Fe, Al, Si, humus, B CaCO, CaSO,; or loss of CaCO,; or accumulation of sesquioxides; or subsurface soil structure. CB Dominantly C horizon characteristics but also or CA Contains attributes of the B or A horizon. C/B Discrete, intermingled bodies of C and B or A or C/A material; majority of horizon is C material. C Little or no pedogenic alteration, unconsolidated earthy material, soft bedrock. L Limnic soil materials. A layer of liquid water (W) or permanently frozen W water (Wf) within or beneath the soil (excludes water/ice above soil, M Root -limiting subsoil layers of human -manufactured materials. R Bedrock, strongly cemented to indurated. HORIZON SUFFIXES —Historically referred to as "Horizon Subscripts,' "Subordinate Distinctions,- "Horizon -Designation_ Suffix" in NASIS, and as "Suffix Symbols" in soil taxonomy 1. (Historical designations and conversions are shown in the "Soil Taxonomy" section.) Horizon suffix Criteria I (expanded details listed in "Soil Taxonomy" section) is Highly decomposed organic matter (used only with O) a ) (proposed) Accumulation of anhydrite (CaSO b Buried genetic horizon (not used with C horizons) c Concretions or nodules co Coprogenous earth (used only with Q d Densic layer (physically root restrictive) di I Diatomaceous earth (used only with L) is decomposed organic matter (used only with with O) f Permanently frozen soil or ice (permafrost); continuous subsurface ice; not seasonal ice ff Permanently frozen soil ("Dry" permafrost); no continuous ice; not seasonal ice g Strong gley in Illuvial organic matter accumulation Slightly decomposed organic matter (used only with O) j larosite accumulation jj Evidence of cryoturbation k Pedogenic CaCO, accumulation (<50%by vol.) kk Major pedogenic CaCO, accumulation (>50%by vol.) m Continuous cementation(pedogenic) me Marl (used only with L) in Pedogenic, exchangeable sodium accumulation o Residual sesquioxide accumulation (pedogenic) p Plow layer or other artificial disturbance q Secondary (pedogenic) silica accumulation Weathered or soft bedrock Illuvial sesquioxide and organic matter accumulation se Presence of sulfides (in mineral or organic horizons) ss Slickensides t Illuvial accumulation of silicate clay u Presence of human -manufactured materials (artifacts) v Plinthite Weak color or structure within B (used only with B) x Fragipan characteristics y Accumulation of gypsum yy Dominance ofgypsum(o>50%by vol.) z Pedogenic accumulation of salt more soluble than gypsum SOIL TEXTURE Soil texture is the numerical proportion (weight percentage) of the sand, silt, and clay separates in the fine -earth fraction (52 mm). Sall texture is field estimated by hand or lab meai. by hydrometer or pipette and placed within the textural triangle to obtain Texture Class. Rerord the Texture Class; e.g., bam; or Subclass; e.g., fine sandy loam; or choose a Term in Lieu of Texture; e.g., gravel. If appropriate, use a Texture Class Modifier; e.g „gravelly loam, NOTE. Soil Texture includes only the fine -earth fraction (52 mhi "Whole -mil Particle -Size Distribution" incl utlas the fine -earth Fraction (52 mm, wt %) and manse fragments (>2 mm). (NOTE: For fragments >76 mm in diameter, visually estimate the volume percent, which is then converted to a weight basis using the estimated particle density [pit] and bulk density [BJ.) TEXTURE CLASS — Texture Class or Subclass Code Conv. NASIS Coarse Sand s COS Sand s S Fine Sand fs FS Very Fine Sand vfs VFS Loamy Coarse Sand Icos LOOS Loamy Sand Is LS Loamy Fine Sand Ifs LFS Loamy Very Fine Sand Ivfs LVFS Coarse Sandy Loam coal COST Sandy Loam sl SL Fine Sandy Loam fsl FSL Very Fine Sandy Loam vfsl VFSL Loam I L Silt Loam all SIL Silt si SI Sandy Clay Loam scl I SCL Clay Loam cl CL Silty Clay Loam slcl SICL Sandy Clay sc SC Silty Clay sic SIC Clay c C (Soil) Textural Triangle: Flne Earth Textu'e Classes ( r Tn day �N d s 6p A silty i ay day J �dav o / dayloam silty day loan ra :anay day loam �u loam W silt loam saa„asaaev loam n 0 0 0 0 0 0 0 0 0 0 �— Sand Separate, %o — TEXTURE MODIFIERS —Conventions for using "Rock Fragment Texture Modifiers" and for using textural adjectives that convey the '-A volume' ranges for Rock Fragment - Quantity and Size. Frag• Rock Fragment Modifier Usage Content Vol. a/o <15 No texture class modifier (noun only; e, g., loam). 15 to <35 Use fragment -size adjective with texture class; e.g., gravelly loam. 35 to <60 Use "very' with fragment -size adjective with texture class; e.g., very gravelly loam. 60 to <90 Use "extremely" with fragment -size adjective with texture class; e.g., extremely gravelly loam. >_90 No adjective or modifier. If <10% fine earth, use the appropriate fragment -size class name for the dominant size class; e.g., gravel. Use Terms Used in Lieu of Texture (see table on P. 2-43). DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 CONSISTENCE Consistence is the degree and kind of cohesion and adhesion that soil exhibits and/or the resistance of soil to deformation or rupture under an applied stress. Soil -water state strongly influences consistence. Field evaluations of consistence include: Rupture Resistance (Blocks, Peds, and Clods; or Surface Crusts and Plates), Manner of Failure (Brittleness, Fluidity, Smeariness), Stickiness, Plasticity, and Penetration Resistance. Historically, consistence applied to dry, moist, or wet soil as observed in the field. Wet consistence evaluated stickiness and plasticity. Rupture Resistance now applies to dry soils and to soils in a water state from moist through wet. Stickiness and Plasticity of soil are independent evaluations. RUPTURE RESISTANCE —A measure of the strength of soil to withstand an applied stress. Separate estimates of Rupture Resistance are made for Blocks/Peds/Clods and for Surface Crusts and Plates of soil. Block -shaped specimens should be approximately 2.8 cm across. If 2.8-cm cubes (e.g., = 2.5-3.1 cm, or I inch) are not obtainable, use the following equation and the table below to calculate the stress at failure: [(2.8 cm/cube length Chl X estimated stress (N) at failure)]; e.g., for a 5.6-cm cube [(2.8/5.6)2 X 20 NJ = 5 N - Soft Class. Plate -shaped specimens (surface crusts or platy structure) should be approximately 1.0-1.5 cm long by 0.5 cm thick (or the thickness of occurrence, if <0.5 cm thick). RUPTURE RESISTANCE FOR: Blocks, Peds, and Clods —Estimate the class by the force required to rupture (break) a soil unit. Select the column for the appropriate soil water state (dry vs. moist) and/or the Cementation column, if applicable. Dry' Moist Cementation Specimen class Code class Code= class Code = Fails Under Loose L Loose L [Not Applicable] [Intact specimen d(lo) m(lo) not obtainable] Soft S Very VFR Non- NC Very slight force Friable cemented between fingers. d(so) m(vfr) <8 N Slightly SH Friable FR Extremely EW Hard Weakly Slight force Cemented between fingers. 8 to <20 N d(sh) m(fr) Mod. MH Firm FI Very vW Hard Weakly Moderate force Cemented between fingers. 20 to <40 N d(h) m(f) Hard HA Very VFI Weakly W Strong force Firm Cemented between fingers. d(vh) m(vfi) c(w) 40 to <80 N Very VH Extr. EF Moderately M Moderate force Hard Firm Cemented between hands. d(vh) m(efi) 80 to <160 N Extr. EH Slightly SR Strongly ST Foot pressure by Hard Rigid Cemented full body weight. d(eh) m(efi) c(s) 160 to <600 N Rigid R Rigid R Very vs Strongly Blow of <3I but Cemented not body weight. 800 N to <3 I d(eh) m(efi) Very VR Very VR Indurated I Blow of >:3 ] Rigid Rigid (3 I = 2 kg weightdropped d(eh) m(efi) c(I) Is cm) STICKINESS —The capacity of soil to adhere to other objects. Stickiness is estimated at the moisture content that displays the greatest adherence when pressed between thumb and forefinger. Stickiness Code Criteria: work moistened soil Conv. NASIS Class between thumb and forefinger Nonsticky (w) so SO Little or no soil adheres to fingers after release of pressure. Slightly Soil adheres to both fingers after Sticky (w) ss SS release of pressure. Soil stretches little on separation of fingers. Moderately Soil adheres to both fingers after Sticky (w) s MS release of pressure. Soil stretches some on separation of fingers. Soil adheres firmly to both fingers Very Sticky (w) vs VS after release of pressure. Soil stretches greatly upon separation of fingers. ' Historically, the Moderately Sticky class was simply called Sticky. PLASTICITY The degree to which "puddled" or reworked soil can be permanently deformed without rupturing. The evaluation is made by forming a roll (wire) of soil at a water content where the maximum plasticity is expressed. Plasticity Code Criteria: make a roll of soil Class Cori NASIS 4 cm long Will not form a roll 6 mm in Nonplastic (w) po PO diameter, or if a roll is formed, it can't support itself if held on end. Slightly (w) ps SP 6 mm diameter roll supports itself; Plastic 4 mm diameter roll does not. Moderately (w) p MP 4 mm diameter roll supports itself; Plastics 2 mm diameter roll does not. Very (w} vp VP 2 mm diameter roll supports its Plastic weight. • • • __N NF Nil Nil 2 mm 4 mm 6 mm 4 cm SOIL COLOR DECISION FLOWCHART FOR DESCRIBING SOIL COLORS —Use the following chart to decide how and with which data elements the color patterns of a soil or soil feature should be described. Matrix Color list in sequence, dominant first Color >Yes Is the coloamatrix or colMixed/ Intermingled No i.e., discrete, mixed, or transitional horizons, such as BIA Other Colors Mottle onmatrix colors) No color associated with <1s lithochromic color; coat/stain, film, e.g., 10YR 811 nnranrrannn nr gibbsite; gray shales Yes � Is the feature -- formed by oxidation and reduction processes? Yes Redoximorphic Feature (RMF) Concentration, depletion, or reduced matrix color Non- redoximorphic Feature No Concentration or Ped and Void Surface Feature; e.g., carbonate mass, clay film, and organic NOTE., Reduced matrix color is described as a matrix color and in the associated "(Soil Color) - Location or Condition Described Table." (SOIL) MATRIX COLOR —Record the Color(s), Moisture State, and Location or Condition. (Soil) Matrix Color - (Soil) Color —Identify the soil matrix color(s) with Munsell* notation (Hue, Value, Chrome); e.g., 10YR 3/2. For neutral colors, chroma is zero but not shown; e.g., N 4/. For other gley colors, use appropriate notation (see Munsell(A) gley pages; e.g., 5GY6/1). For narrative descriptions (soil survey reports, Official Soil Series Descriptions), both the verbal name and the Munsell* notation are given; e.g., dark brown, 10YR 3/3. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Reference: Schoeneberger, P.J., D.A. Wysocki, E.C. Benham, and Soil Survey Staff. 2012. Field book for describing and sampling soils, Version 3.0. Natural Resources Conservation Service, National Soil Survey Center, Lincoln, NE. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 LOCATION HAYESVILLE NC+GA SC TN VA Established Series Rev. RM-AG-DHK 04/2001 HAYESVILLE SERIES The Hayesville series consists of very deep, well drained soils on gently sloping to very steep ridges and side slopes of the Southern Appalachian Mountains. They most commonly formed in residuum weathered from igneous and high-grade metamorphic rocks such as granite, granodiorite, mica gneiss and schist; but in some places formed from thickly -bedded metagraywacke and metasandstone. On steeper slopes the upper part of some pedons may have some colluvial influence. Mean annual air temperature is 55 degrees F., and average annual precipitation is about 56 inches near the type location. Slopes range from 2 to 60 percent. TAXONOMIC CLASS: Fine, kaolinitic, mesic Typic Kanhapludults TYPICAL PEDON: Hayesville loam --wooded. (Colors are for moist conditions unless otherwise stated.) Al- 0 to 1 inch; brown (IOYR 4/3) loam; moderate fine and medium granular structure; very friable; many fine and medium roots; moderately acid; abrupt smooth boundary. (1 to 5 inches thick) A2--1 to 5 inches; brown (IOYR 513) loam; weak medium granular structure; very friable; many fine and medium roots; moderately acid; abrupt smooth boundary. (0 to 7 inches thick) BA--5 to 9 inches; yellowish red (5YR 518) clay loam; weak medium subangular blocky structure; friable; common medium and fine roots; few fine flakes of mica; strongly acid; clear smooth boundary. (0 to 6 inches thick) Btl--9 to 26 inches; red (2.5YR 4/6) clay; moderate medium and coarse subangular blocky structure; friable to firm; common distinct clay films on faces of peds; few to common soft fragments of rock; few fine flakes of mica; strongly acid; gradual smooth boundary. Bt2--26 to 38 inches; red (2.5YR 5/6) clay loam; weak medium subangular blocky structure; friable; few faint clay films on faces of peds; common coarse fragments of rock; soft and hard; few partially weathered feldspar and dark minerals; few flakes of mica; strongly acid; gradual irregular boundary. (Combined thickness of the Bt horizon is 11 to 45 inches) BC--38 to 48 inches; yellowish red (5YR 5/6) and red (2.5YR 4/6) sandy clay loam; massive; friable; many grayish and whitish streaks of soft gneiss; gray and white colors increase in abundance with depth; common flakes of mica; few hard fragments of gneiss; strongly acid. (6 to 29 inches thick) C--48 to 60 inches; strong brown (7.5YR 5/8) saprolite that is fine sandy loam; massive (rock structure); very friable; common fine flakes of mica; strongly acid. TYPE LOCATION: Clay County, North Carolina; 2.5 miles southeast of Hayesville, on Swain Road in road cut on north side of road. RANGE IN CHARACTERISTICS: Solum thickness is 30 to 60 inches. Depth to bedrock is greater than 60 inches and ranges to more than 10 feet. Content of rock fragments ranges from 0 to 40 percent by volume in the A and E horizons and 0 to 15 percent in the B and C horizons. Rock fragments are commonly pebbles, cobbles, or stones, but may include charmers or flagstones. Reaction is extremely acid to moderately acid unless limed. Limed soils are typically slightly acid to neutral in the upper part. Flakes of mica range from none to common in DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 the A and B horizons above a depth of 40 inches, and from none to many in the B and C horizons below 40 inches. The A or Ap horizon has hue of 5YR to 1 OYR, value of 3 to 6, and chroma of 2 to 6. Where the value is less than 3, it is less than 7 inches thick. The A horizon is loam, fine sandy loam, sandy loam, or very fine sandy loam in the fine -earth fraction, or eroded pedons are sandy clay loam or clay loam. The E horizon, where present, has hue of 7.5YR or IOYR, value of 4 to 6, and chroma of 3 to 8. It is loam, fine sandy loam, sandy loam, or very fine sandy loam in the fine -earth fraction. The BA horizon, where present, has hue of 2.5YR to 1 OYR, value of 4 to 6, and chroma of 4 to 8. Texture is loam, clay loam, or sandy clay loam. The Bt horizon has hue of 1 OR to 5YR, value of 4 or 5, and chroma of 6 or 8. Mottles, if they occur, are in shades of red, yellow, or brown. Texture is clay or clay loam. The BC or CB horizon, where present, has hue of 1 OR to 7.5YR, value of 4 to 6, and chroma of 6 or 8. Mottles, if they occur, are in shades of red, yellow, or brown. Texture is sandy clay loam, clay loam, or loam. The C horizon is saprolite that is sandy clay loam, loam, sandy loam, or fine sandy loam. It is variable in color. COMPETING SERIES: This is the only other known series in this family. Bradson, Brevard, Braddock, Clifton, Evard, Fannin, and Nantahala (tentative) soils are in closely related families. Bradson and Braddock soils have water worn coarse fragments. In addition, the Braddock soils have mixed mineralogy. Brevard, Evard, and Fannin soils have less than 35 percent clay in the control section. Nantahala (tentative) and Clifton soils have mixed mineralogy. Note: Competing series have not been updated since most of these will also require reclassification using the 7th Edition of Keys to Soil Taxonomy (1996). GEOGRAPHIC SETTING: The Hayesville soils are on gently sloping to very steep ridges and side slopes in the intermountain plateaus, low rolling hills, and valleys of the southern Appalachian Mountains. Slopes range from 2 to 60 percent. Elevation ranges from 1400 to 4000 feet. The soils most commonly formed in residuum from igneous and high-grade metamorphic rocks such as granite, granodiorite, mica gneiss and schist; but in some places formed from thickly -bedded metagraywacke and metasandstone. There may be some colluvial influence on steep slopes. Mean annual air temperature is ranges from 46 to 57 degrees F., and average annual precipitation ranges from about 40 to 60 inches. GEOGRAPHICALLY ASSOCIATED SOILS: In addition to the similar Braddock, Clifton, Evard, and Fannin soils these include the Brevard, Cullasaja, Saunook, Tate, Tuckasegee, and Tusquitee soils. All except Braddock and Clifton soils have less than 35 percent clay in the control section. Braddock soils are on high terraces. Clifton, Evard, and Fannin soils are on ridges and side slopes. Brevard, Cullasaja, Saunook, Tate, Tuckasegee, and Tusquitee soils are on colluvial fans and toe slopes. DRAINAGE AND PERMEABILITY: Well drained; moderate permeability in the subsoil and moderately rapid permeability in the underlying material; medium internal drainage. Runoff class low on gentle slopes, medium on strong and moderately steep slopes, and high on steeper slopes. Runoff is much lower where forest litter has little or no disturbance. USE AND VEGETATION: About one-half of the acres of this soil is in cultivation. Common trees in wooded areas are yellow- poplar, eastern white pine, northern red oak, pitch pine, shortleaf pine and Virginia pine. The understory includes flowering dogwood, rhododendron, mountain laurel and sourwood. Cleared areas are used for cultivated crops such as corn, small grain, pasture, hayland, burley tobacco, vegetable crops and Christmas trees. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 DISTRIBUTION AND EXTENT: Mountain areas of North Carolina, Virginia, South Carolina, Georgia, and Tennessee. The series is of large extent. MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia SERIES ESTABLISHED: Clay County, North Carolina; 1935. REMARKS: The classification of the Hayesville series was changed in April 1989 to clayey, kaolinitic, mesic Typic Kanhapludults. This is change is based on lab data from South Carolina, North Carolina, and Virginia that indicates presence of a kandic horizon. The May 1995 revision added thickly -bedded metagraywacke and metasandstone as allowable parent materials for Hayesville soils. Laboratory data from North Carolina State University provided support for Hayesville soils being formed from these materials in Cherokee County, NC. The 12/97 revision changes the particle size class from clayey to fine per the 7th Edition of Keys to Soil Taxonomy (1996). Diagnostic horizons and features recognized in this pedon are: Ochric epipedon: The zone from 0 to 5 inches (Al and A2 horizons). Kandic horizon: The zone from 5 to 48 inches (BA, Bt, and BC horizons). Argillic horizon: The zone from 5 to 48 inches (BA, Bt, and BC horizons). MLRA: 130 SIR(s): NC0013, NCO151 (STONY) ADDITIONAL DATA: A Southern Cooperative Series Bulletin No. 157, April 1971, "Soils of the Hayesville, Cecil, and Pacolet series in the Southern Appalachian and Piedmont Regions of the United States." Characterization data is available from the National Soil Survey Laboratory, Lincoln, NE; pedon numbers S60- NC-043-001 and -002; S60-NC-089-002; S78-NC-021-001; S88-NC-115-001; S91-NC-021-001, -001A, and -012. Revised: 9/95-RM-AG; 1/98-DHK National Cooperative Soil Survey U.S.A. DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Stormwater Collection System DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Project: Suncap wgla #: 20176 Date: 5/10/2021 Location: Town of Mills River, North Carolina Design Storm: 25 yr I = 8.08 Tc (min) = 5.00 Grass c = 0.30 Impervious c = 0.90 Wooded c = 0.20 NOAA Atlas 14, Volume 2, Version 3 Minimum Pipe Dia = 15 Structure # Drainage Area (ac.) Grass Area (ac.) Misc Imp Area (ac.) Wooded Area (ac.) Weighted c Q (cfs) Top/Throa t Elev Inv In Elev Inv Out Elev Type 1 0.61 0.18 0.16 0.27 0.41 2.04 2147.45 2140.20 2140.20 OTCB 2 0.66 0.44 0.00 0.22 0.27 1.42 2133.00 2128.00 2128.00 OCS 3 0.00 0.00 0.00 0.00 0.00 0.00 2133.93 2117.00 2117.00 JB 4 1.08 0.39 0.29 0.40 0.42 3.70 2119.00 2115.00 2115.00 OTCB 5 1.78 1.69 0.09 0.00 0.33 4.75 2117.00 2106.40 2106.40 OCS 6 0.00 0.00 0.00 0.00 0.00 0.00 2089.00 2083.00 2083.00 JB 7 0.00 0.00 0.00 0.00 0.00 0.00 2085.00 2081.00 2081.00 JB 8 0.00 0.00 0.00 0.00 0.00 0.00 2110.00 2104.00 2104.00 JB 9 2.27 2.24 0.00 0.03 0.30 5.48 2098.00 2093.00 2093.00 OCS 10 1.75 1.75 0.00 0.00 0.30 4.24 2127.00 2122.00 2122.00 OCS 11 1.33 1.33 0.00 0.00 0.30 3.22 2117.00 2110.50 2110.50 OCS 13 2.39 0.03 2.36 0.00 0.89 17.23 2121.73 2116.73 2116.73 Cl 14 0.12 0.00 0.12 0.00 0.90 0.87 2121.17 2116.17 2116.17 Cl 15 1.55 0.00 1.55 0.00 0.90 11.27 2122.33 2117.33 2117.33 Cl 16 1.63 0.00 1.63 0.00 0.90 11.85 2122.33 2117.33 2117.33 Cl 17 1.44 0.04 1.40 0.00 0.88 10.28 2122.83 2117.83 2117.83 Cl 18 0.10 0.00 0.10 0.00 0.90 0.73 2124.28 2119.28 2119.28 Cl 19 0.25 0.05 0.20 0.00 0.78 1.58 2129.89 2124.89 2124.89 Cl 20 3.59 0.12 3.47 0.00 0.88 25.52 2129.08 2122.88 2122.88 Cl 21 0.89 0.16 0.73 0.00 0.79 5.70 2126.74 2121.74 2121.74 Cl 22 1.79 0.00 1.79 0.00 0.90 13.02 2127.82 2120.82 2120.82 Cl 23 0.15 0.02 0.13 0.00 0.82 0.99 2145.44 2141.44 2141.44 Cl 24 0.17 0.02 0.15 0.00 0.83 1.14 2142.52 2138.52 2138.52 Cl 25 0.17 0.02 0.15 0.00 0.83 1.14 2139.60 2135.60 2135.60 Cl 26 0.16 0.01 0.15 0.00 0.86 1.12 2145.89 2141.89 2141.89 Cl 27 0.18 0.02 0.16 0.00 0.83 1.21 2142.97 2138.97 2138.97 Cl 28 0.18 0.02 0.16 0.00 0.83 1.21 2140.05 2134.79 2134.79 Cl 29 0.17 0.02 0.15 0.00 0.83 1.14 2137.13 2133.13 2133.13 Cl 30 0.17 0.02 0.15 0.00 0.83 1.14 2134.21 2130.21 2130.21 Cl 31 0.17 0.02 0.15 0.00 0.83 1.14 2131.29 2127.95 2127.95 Cl 32 0.22 0.03 0.19 0.00 0.82 1.45 2131.30 2128.28 2128.28 Cl 33 0.23 0.06 0.17 0.00 0.74 1.38 2131.14 2127.88 2127.88 Cl 34 0.04 0.01 0.03 0.00 0.75 0.24 2148.27 2144.27 2144.27 Cl 35 0.16 0.01 0.15 0.00 0.86 1.12 2145.35 2141.35 2141.35 Cl 36 0.10 0.04 0.06 0.00 0.66 0.53 2146.20 2142.20 2142.20 Cl 37 0.15 0.04 0.11 0.00 0.74 0.90 2142.24 2138.24 2138.24 Cl 38 0.17 0.02 0.15 0.00 0.83 1.14 2142.43 2137.96 2137.96 Cl 39 0.17 0.02 0.15 0.00 0.83 1.14 2139.51 2135.51 2135.51 Cl 40 0.15 0.01 0.14 0.00 0.86 1.04 2136.08 2132.08 2132.08 Cl 41 0.17 0.02 0.15 0.00 0.83 1.14 2136.59 2131.80 2131.80 Cl 42 0.17 0.02 0.15 0.00 0.83 1.14 2133.67 2129.67 2129.67 Cl DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 43 0.17 0.02 0.15 0.00 0.83 1.14 2130.75 2127.19 2127.19 CI 44 0.22 0.07 0.15 0.00 0.71 1.26 2130.60 2127.12 2127.12 CI 45 0.32 0.12 0.20 0.00 0.68 1.75 2130.14 2126.84 2126.84 CI 46 0.14 0.02 0.12 0.00 0.81 0.92 2132.32 2126.56 2126.56 CI 47 0.51 0.18 0.33 0.00 0.69 2.84 2130.10 2126.29 2126.29 CI 48 0.43 0.10 0.18 0.15 0.52 1.79 2149.53 2145.53 2145.53 CI 49 0.38 0.15 0.19 0.04 0.59 1.81 2138.00 2134.00 2134.00 CI 50 0.26 0.03 0.23 0.00 0.83 1.75 2139.65 2134.65 2134.65 CI 51 0.21 0.02 0.19 0.00 0.84 1.43 2136.41 2132.41 2132.41 CI 52 0.10 0.01 0.09 0.00 0.84 0.68 2137.13 2132.13 2132.13 CI 53 0.30 0.09 0.21 0.00 0.72 1.75 2120.93 2116.93 2116.93 CI 54 0.04 0.00 0.04 0.00 0.90 0.29 2121.35 2116.35 2116.35 CI 0.00 0.00 IN 1 1.84 0.74 0.22 0.88 0.32 4.82 2137.00 2137.00 FES 0.00 0.00 OUT 1 0.00 0.00 2080.90 2080.90 LS OUT 2 0.00 0.00 2097.00 2097.00 FES OUT 3 0.00 0.00 2108.90 2108.90 LS OUT 4 0.00 0.00 2097.00 2097.00 FES OUT 5 0.00 0.00 2097.00 2097.00 FES OUT 6 0.00 0.00 2097.00 2097.00 FES OUT 7 0.00 0.00 2097.00 2097.00 FES OUT 8 0.00 0.00 2097.00 2097.00 FES OUT 9 0.00 0.00 2117.00 2117.00 FES OUT 10 0.00 0.00 2117.00 2117.00 FES OUT 11A 0.00 0.00 2126.00 2126.00 FES OUT 11 B 0.00 0.00 2126.00 2126.00 FES OUT 12 0.00 0.00 2132.00 2132.00 FES OUT 13 0.00 0.00 2116.00 2116.00 FES OUT 14 0.00 0.00 2116.00 2116.00 FES DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 c �, U) Eco � W Z) U) to E Cu L o U) �' Throat Elev (Upstream Inlet) Inv Elev (Upstream Inlet) Inv Elev (Dnstream Inlet) Inlet Depth (Upstream Inlet) Slope (%) Material Manning's n Branch Q (cfs) Total Q (cfs) Dia. Theo. (in) 76- Q o -E-I Qpipe (cfs) Vpipe (fps) A 1 to 2 120 2147.45 2140.20 2128.00 7.25 10.17% HDPE 0.011 2.04 2.04 5.9 24 85.48 27.21 B 2 to 3 272 2133.00 2128.00 2117.00 5.00 4.04% HDPE 0.011 1.42 7.06 11.2 24 53.91 17.16 C IN 1 to 3 399 N/A 2137.00 2117.00 N/A 5.01% HDPE 0.011 4.82 4.82 9.4 18 27.87 15.77 D 3 to 5 349 2133.93 2117.00 2106.40 16.93 3.04% HDPE 0.011 0.00 11.88 14.4 24 46.72 14.87 E 4 to 5 86 2119.00 2115.00 2106.40 4.00 10.00% HDPE 0.011 3.70 3.70 7.4 15 24.21 19.73 F 6 to 7 79 2089.00 2083.00 2081.00 6.00 2.53% HDPE 0.011 0.00 56.98 26.9 30 77.34 15.75 G 7 to OUT 1 10 2085.00 2081.00 2080.90 4.00 1.00% HDPE 0.011 0.00 56.98 32.0 36 79.04 11.18 H 8 to OUT 2 98 2110.00 2104.00 2097.00 6.00 7.14% HDPE 0.011 0.00 50.49 21.1 30 129.90 26.46 I 9 to 6 76 2098.00 2093.00 2083.00 5.00 13.16% HDPE 0.011 5.48 56.98 19.7 24 97.24 30.95 J 10 to 8 53 2127.00 2122.00 2104.00 5.00 33.96% HDPE 0.011 4.24 50.49 15.8 30 283.26 57.70 K1 11 to OUT 3 220 2117.00 2110.50 2108.90 6.50 0.73% HDPE 0.011 3.22 37.91 29.1 30 41.45 8.44 L 13 to OUT 4 58 2121.73 2116.73 2097.00 5.00 34.02% HDPE 0.011 17.23 17.23 10.5 15 44.65 36.38 M 14 to OUT 5 58 2121.17 2116.17 2097.00 5.00 33.05% HDPE 0.011 0.87 0.87 3.5 15 44.01 35.86 N 15 to OUT 6 59 2122.33 2117.33 2097.00 5.00 34.46% HDPE 0.011 11.27 11.27 9.0 15 44.93 36.62 O 16 to OUT 7 58 2122.33 2117.33 2097.00 5.00 35.05% HDPE 0.011 11.85 11.85 9.1 15 45.32 36.93 P 17 to OUT 8 58 2122.83 2117.83 2097.00 5.00 35.91% HDPE 0.011 10.28 10.28 8.6 15 45.87 37.38 Q 18 to OUT 9 24 2124.28 2119.28 2117.00 5.00 9.50% HDPE 0.011 0.73 0.73 4.1 15 23.59 19.23 R 19 to 20 159 2129.89 2124.89 2122.88 5.00 1.26% HDPE 0.011 1.58 1.58 8.0 15 8.61 7.01 S 20 to 21 228 2129.08 2122.88 2121.74 6.20 0.50% HDPE 0.011 25.52 27.10 27.6 30 34.37 7.00 T 21 to 22 148 2126.74 2121.74 2120.82 5.00 0.62% HDPE 0.011 5.70 32.80 28.4 30 38.32 7.81 U 22 to OUT 10 30 2127.82 2120.82 2117.00 7.00 12.73% HDPE 0.011 13.02 45.81 18.3 30 173.44 35.33 V 23 to 24 73 2145.44 2141.44 2138.52 4.00 4.00% HDPE 0.011 0.99 0.99 5.4 15 15.31 12.48 W 24 to 25 73 2142.52 2138.52 2135.60 4.00 4.00% HDPE 0.011 1.14 2.13 7.2 15 15.31 12.48 X 25 to 50 57 2139.60 2135.60 2134.65 4.00 1.67% HDPE 0.011 1.14 3.27 9.9 15 9.88 8.05 Y 26 to 27 73 2145.89 2141.89 2138.97 4.00 4.00% HDPE 0.011 1.12 1.12 5.6 15 15.31 12.48 Z 27 to 28 73 2142.97 2138.97 2134.79 4.00 5.73% HDPE 0.011 1.21 2.33 6.9 15 18.32 14.93 AA 28 to 29 73 2140.05 2134.79 2133.13 5.26 2.27% HDPE 0.011 1.21 3.54 9.7 15 11.54 9.41 BB 29 to 30 73 2137.13 2133.13 2130.21 4.00 4.00% HDPE 0.011 1.14 4.68 9.7 15 15.31 12.48 CC 30 to 31 73 2134.21 2130.21 2127.95 4.00 3.10% HDPE 0.011 1.14 5.82 11.0 15 13.47 10.98 DID 31 to 33 13 2131.29 2127.95 2127.88 3.34 0.54% HDPE 0.011 1.14 6.96 16.3 18 9.13 5.17 EE 32 to 33 80 2131.30 2128.28 2127.88 3.02 0.50% HDPE 0.011 1.45 1.45 9.2 15 5.41 4.41 FF 33 to 44 152 2131.14 2127.88 2127.12 3.26 0.50% HDPE 0.011 1.38 9.79 18.8 24 18.96 6.03 GG 34 to 35 73 2148.27 2144.27 2141.35 4.00 4.00% HDPE 0.011 0.24 0.24 3.2 15 15.31 12.48 HH 35 to 38 73 2145.35 2141.35 2137.96 4.00 4.64% HDPE 0.011 1.12 1.36 5.9 15 16.50 13.44 11 36 to 37 99 2146.20 2142.20 2138.24 4.00 4.00% HDPE 0.011 0.53 0.53 4.3 15 15.31 12.48 DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 JJ 37 to 38 55 2142.24 2138.24 2137.96 4.00 0.51% HDPE 0.011 0.90 1.43 9.1 15 5.46 4.45 KK 38 to 39 73 2142.43 2137.96 2135.51 4.47 3.36% HDPE 0.011 1.14 3.93 9.3 15 14.02 11.43 LL 39 to 41 73 2139.51 2135.51 2131.80 4.00 5.08% HDPE 0.011 1.14 5.07 9.5 15 17.26 14.06 MM 40 to 41 55 2136.08 2132.08 2131.80 4.00 0.51% HDPE 0.011 1.04 1.04 8.1 15 5.46 4.45 NN 41 to 42 73 2136.59 2131.80 2129.67 4.79 2.92% HDPE 0.011 1.14 7.25 12.1 15 13.08 10.66 00 42 to 46 62 2133.67 2129.67 2126.56 4.00 5.02% HDPE 0.011 1.14 8.39 11.5 15 17.14 13.97 PP 43 to 44 13 2130.75 2127.19 2127.12 3.56 0.54% HDPE 0.011 1.14 1.14 8.3 15 5.62 4.58 QQ 44 to 45 55 2130.60 2127.12 2126.84 3.48 0.51% HDPE 0.011 1.26 12.19 20.4 24 19.13 6.09 RR 45 to OUT 11B 85 2130.14 2126.84 2126.00 3.30 0.99% HDPE 0.011 1.75 13.94 18.9 24 26.65 8.48 SS 46 to 47 53 2132.32 2126.56 2126.29 5.76 0.51% HDPE 0.011 0.92 9.31 18.4 24 19.13 6.09 TT 47 to OUT 11A 58 2130.10 2126.29 2126.00 3.81 0.50% HDPE 0.011 2.84 12.14 20.4 24 18.96 6.03 UU 48 to 49 256 2149.53 2145.53 2134.00 4.00 4.50% HDPE 0.011 1.79 1.79 6.6 15 16.25 13.24 W 49 to OUT 12 24 2138.00 2134.00 2132.00 4.00 8.33% HDPE 0.011 1.81 3.60 7.6 15 22.10 18.01 WW 50 to 52 63 2139.65 2134.65 2132.13 5.00 4.00% HDPE 0.011 1.75 5.02 9.9 15 15.31 12.48 XX 51 to 52 38 2136.41 2132.41 2132.13 4.00 0.74% HDPE 0.011 1.43 1.43 8.5 15 6.57 5.35 YY 52 to OUT 13 48 2137.13 2132.13 2116.00 5.00 33.60% HDPE 0.011 0.68 7.13 7.6 15 44.37 36.16 ZZ 53 to 54 57 2120.93 2116.93 2116.35 4.00 1.02% HDPE 0.011 1.75 1.75 8.6 15 7.72 6.29 AAA 54 to OUT 14 42 2121.35 2116.35 2116.00 5.00 0.83% HDPE 0.011 0.29 2.04 9.5 15 6.99 5.69 DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Bioretention Cell Supplement DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 SUPPLEMENT-EZ COVER PAGE FORMS LOADED PROJECT INFORMATION 1 1 Project Name Suncap 2 Project Area (ac) 40.42 0 3 Coastal Wetland Area (ac) 4 Surface Water Area (ac) 0 5 Is this project High or Low Density? High 6 Does this project use an off -site SCM? No COMPLIANCE WITH 02H .1003(4) 7 Width of vegetated setbacks provided feet N/A 8 Will the vegetated setback remain vegetated? N/A 9 If BUA is proposed in the setback, does it meet NCAC 02H.1003(4)(c-d)? N/A 10 Is streambank stabilization proposed on this project? No NUMBER AND TYPE OF SCMs: 11 Infiltration System 12 Bioretention Cell 5 13 Wet Pond 14 Stormwater Wetland 15 Permeable Pavement 16 Sand Filter 17 Rainwater Harvesting RWH 18 Green Roof 19 Level Spreader -Filter Strip LS-FS 20 Disconnected Impervious Surface DIS 21 Treatment Swale 22 lDry Pond StormFilter Silva Cell Ba filter Filterra 23 24 25 26 FORMS LOADED DESIGNER CERTIFICATION 27 IName and Title: Or anization: Street address: William R. Buie, PE Project Engineer) 28 WGLA Engineering, PLLC 29 724 5th Avenue West 30 City, State, Zip: Hendersonville, NC 28739 31 Phone numbers : 828 687-7177 32 Email: wbuie@wgla.com Certification Statement: I certify, under penalty of law that this Supplement-EZ form and all supporting information were prepared under my direction or supervision; that the information provided in the form is, to the best of my knowledge and belief, true, accurate, and complete; and that the engineering plans, specifications, operation and maintenance agreements and other supporting information are consistent with the information provided here. \\�„��illirr!�777 ebj�j�° ° 07CO3F2Zq04S8D... o° — ° /1 � rA M y,R+\\\ 6/ 2 5 /2021 Seal Ec DocuSigned by: iwaal r. bb� ,- 07CO3FBF740148D... Signature of Designer Date 6/25/2021 DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 DRAINAGE AREAS 1 Is this a hi h density project? Yes 2 If so, number of drainage areas/SCMs 5 3 Does this project have low density areas? No 4 If so, number of low density drainage areas 0 Is all/part of this project subject to previous rule 5 versions? No FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 1 2 3 4 4 Type of SCM Bioretention Cell A Bioretention Cell B Bioretention Cell C Bioretention Cell D 5 Total drainage area (sq ft 409564 346186 377136 64158 6 Onsite drainage area (sq ft 409564 346186 377136 62254 7 Offsite drainage area (sq ft 0 0 0 1904 8 Total BUA in project (sq ft 307970 sf 273482 sf 265344 sf 16227 sf 9 New BUA on subdivided lots (subject to permitting) s ft 10permitting) New BUA not on subdivided lots (subject to s 307970 sf 273482 sf 265344 sf 15576 sf 11 Offsite BUA (sq ft 651 sf 12 Breakdown of new BUA not on subdivided lots: - Parking (sq ft 259920 sf 48071 sf 260280 sf 15576 sf - Sidewalk (sq ft 5064 sf - Roof (sq ft) 48050 sf 206174 sf - Roadway s ft - Future (sq ft 19211 sf - Other, please specify in the comment box below (sa ft 13 New infiltrating permeable pavement on Isubdivided lots (sq ft 14 New infiltrating permeable pavement not on subdivided lots (sq ft 15permitting) Existing BUA that will remain (not subject to s ft 16 Existing BUA that is already permitted (sq ft 17 Existing BUA that will be removed (sq ft Percent BUA 75% 79% 70% 25% Desi n storm inches 1.3 in 1.3 in 1.3 in 1.3 in Desi n volume of SCM cu ft 31005 cf 27409 cf 26835 cf 1844 cf V Calculation method for design volume Simple Simple Simple Simple IONAL INFORMATION 22 Please use this space to provide any additional information about the drainage area(S)7 DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 DRAINAGE AREAS 1 Is this a hi h density project? Yes 2 If so, number of drainage areas/SCMs 5 3 Does this project have low density areas? No 4 If so, number of low density drainage areas 0 Is all/part of this project subject to previous rule 5 versions? No FORMS LOADED DRAINAGE AREA INFORMATION Entire Site 5 4 Type of SCM Bioretention Cell E 5 Total drainage area (sq ft 117168 6 Onsite drainage area (sq ft 113458 7 Offsite drainage area (sq ft 3710 8 Total BUA in project (sq ft 68825 sf 9permitting) New BUA on subdivided lots (subject to s ft 10permitting) New BUA not on subdivided lots (subject to s 29519 sf 11 Offsite BUA (sq ft 6895 sf 12 Breakdown of new BUA not on subdivided lots: - Parking (sq ft 29519 sf - Sidewalk (sq ft 78 sf - Roof (sq ft) - Roadway s ft - Future (sq ft 32333 sf - Other, please specify in the comment box below (sa ft 13 New infiltrating permeable pavement on Isubdivided lots (sq ft 14 New infiltrating permeable pavement not on subdivided lots (sq ft 15permitting) Existing BUA that will remain (not subject to s ft 16 Existing BUA that is already permitted (sq ft 17 Existing BUA that will be removed (sq ft 18 IPercent BUA 59% 19 Design storm inches 1.3 in 20 Design volume of SCM cu ft 7174 cf 21 Calculation method for design volume Simple DITIONAL INFORMATION 22 Please use this space to provide any additional information about the drainage area(S)7 DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 BIORETENTION CELL 1 IlDrainage area number I A I B I C I D I E 2 IMinimum required treatment volume cu ft ct 214U9 c ct 1644 cf f1l f4 c GENERAL MDC FROM 02H .1050 3 Is the SCM sized to treat the SW from all surfaces at build -out? Yes Yes Yes Yes Yes 4 Is the SCM located away from contaminated soils? No No No No No 5 What are the side slopes of the SCM (H:V)? 3:1 3:1 3:1 3:1 3:1 6 Does the SCM have retaining walls, gabion walls or other engineered side slopes? Yes No Yes No No 7 Are the inlets, outlets, and receiving stream protected from erosion (10-year storm)? Yes Yes Yes Yes Yes 8 Is there an overflow or bypass for inflow volume in excess of the design volume? No No No No No 9 What is the method for dewatering the SCM for maintenance? Pump (preferred) Pump (preferred) Pump (preferred) Pump (preferred) Pump (preferred) 10 If applicable, will the SCM be cleaned out after construction? Yes Yes Yes Yes Yes 11 Does the maintenance access comply with General MDC (8)? Yes Yes Yes Yes Yes 12 Does the drainage easement comply with General MDC (9)? Yes Yes Yes Yes Yes 13 If the SCM is on a single family lot, does (will?) the plat comply with General MDC (10)? N/A N/A N/A N/A N/A 14 Is there an O&M Agreement that complies with General MDC (11)? Yes Yes Yes Yes Yes 15 Is there an O&M Plan that complies with General MDC (12)? Yes Yes Yes Yes Yes 16 Does the SCM follow the device specific MDC? Yes Yes Yes Yes Yes 17 Was the SCM designed by an NC licensed professional? Yes Yes Yes Yes Yes BIORETENTION CELL MDC FROM 02H .1052 18 SHWT elevation (fmsl) 2090.00 2110.00 2118.00 2115.00 2098.00 19 Bottom of the bioretention cell (fmsl) 2093.00 2113.00 2123.00 2128.00 2112.00 20 Ponding depth of the design storm (inches) 12 in 12 in 12 in 12 in 12 in 21 Surface area of the bioretention cell (square feet) 40740 sf 38020 sf 30628 sf 3984 sf 9232 sf 22 Design volume of SCM (cu ft) 42730 cf 39330 cf 37150 cf 4589 cf 9862 cf 23 Is the bioretention cell used for peak attenuation? No No No No No 24 Depth of peak attenuation over planting surface (in) N/A N/A N/A N/A N/A 25 Height of peak attenuation outlet above the planting surface (in) N/A N/A N/A N/A N/A 26 Infiltration rate of the in situ soil (inch/hour) N/A N/A N/A N/A N/A 27 Diameter of the underdrain pipes (if applicable) 4 in 4 in 4 in 4 in 4 in 28 Does the design include Internal Water Storage (IWS)? Yes Yes Yes Yes Yes 29 if so, elevation of the top of the IWS (fmsl) 2095.5 2115.5 2124.5 2130.5 2114.5 30 Elevation of the planting surface (fmsl) 2097 2117 2126 2132 2116 31 What type of vegetation will be planted? (grass, trees/shrubs, other)? Trees/Shrubs Trees/Shrubs Trees/Shrubs Trees/Shrubs Trees/Shrubs 32 Media depth (inches) 36 in 36 in 36 in 36 in 36 in 33 Percentage of medium to coarse washed sand by volume 85% 85% 85% 85% 85% 34 Percentage of fines (silt and clay) by volume 10% 10% 10% 10% 10% 35 Percentage of organic matter by volume 5% 5% 5% 5% 5% 36 Type of organic material Pine Bark Pine Bark Pine Bark Pine Bark Pine Bark 37 Phosphorus Index (P-Index) of media (unitless) 20 20 20 20 20 38 lWill compaction be avoided during construction? Yes Yes Yes Yes Yes 39 Will cell be maintained to a one inch/hour standard? Yes Yes Yes Yes Yes 40 Depth of mulch, if applicable (inches) 4 in 4 in 4 in 4 in 4 in 41 Type of mulch, if applicable Hardwood Hardwood Hardwood Hardwood Hardwood 42 How many clean out pipes are being installed? 19 40 11 41 12 43 Type of pretreatment that will be used: Forebay Forebay Forebay Forebay Forebay ADDITIONAL INFORMATION 44 Please use this space to provide any additional information about the bioretention cell(s): Bioretention 4 7:17 AM 6/25/2021 DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 WATER QUALITY VOLUME CALCULATION WGLA Engineering, PLLC Project: Date: Description: Suncap 5/10/2021 Bio-Cell #A Determine Runoff Volume (NCDENR BMP 3.3.1) Rv=0.05+0.9xIA Drainage Area = Impervious Area = Impervious Fraction (IA) = Rv = 9.40 (acres) 7.07 (acres) 0.752 0.727 V = 3630 x RD x Rv x A (Volume to be controlled) Rp = runoff depth Required Volume V = Provided V = 1.25 (inches) P90 Storm 31,005 cf 42,730 cf wgla.com DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 WATER QUALITY VOLUME CALCULATION WGLA Engineering, PLLC Project: Date: Description: Suncap 5/10/2021 Bio-Cell #B Determine Runoff Volume (NCDENR BMP 3.3.1) Rv=0.05+0.9xIA Drainage Area = Impervious Area = Impervious Fraction (IA) = Rv = 7.95 (acres) 6.27 (acres) 0.760 V = 3630 x RD x Rv x A (Volume to be controlled) Rp = runoff depth Required Volume V = Provided V = 1.25 (inches) P90 Storm 27,409 cf 39,330 cf wgla.com DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 WATER QUALITY VOLUME CALCULATION WGLA Engineering, PLLC Project: Date: Description: Suncap 5/10/2021 Bio-Cell #C Determine Runoff Volume (NCDENR BMP 3.3.1) Rv=0.05+0.9xIA Drainage Area = Impervious Area = Impervious Fraction (IA) = Rv = 8.66 (acres) 6.09 (acres) 0.703 V = 3630 x RD x Rv x A (Volume to be controlled) Rp = runoff depth Required Volume V = Provided V = 1.25 (inches) P90 Storm 26,835 cf 37,150 cf wgla.com DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 WATER QUALITY VOLUME CALCULATION WGLA Engineering, PLLC Project: Date: Description: Suncap 5/10/2021 Bio-Cell #D Determine Runoff Volume (NCDENR BMP 3.3.1) Rv=0.05+0.9xIA Drainage Area = Impervious Area = Impervious Fraction (IA) = Rv = 1.47 (acres) 0.37 (acres) 0.252 0.277 V = 3630 x RD x Rv x A (Volume to be controlled) Rp = runoff depth Required Volume V = Provided V = 1.25 (inches) P90 Storm 1,844 cf 4,589 cf wgla.com DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 WATER QUALITY VOLUME CALCULATION WGLA Engineering, PLLC Project: Date: Description: Suncap 5/10/2021 Bio-Cell #E Determine Runoff Volume (NCDENR BMP 3.3.1) Rv=0.05+0.9xIA Drainage Area = Impervious Area = Impervious Fraction (IA) = Rv = 3.18 (acres) 1.58 (acres) 0.497 0.497 V = 3630 x RD x Rv x A (Volume to be controlled) Rp = runoff depth Required Volume V = Provided V = 1.25 (inches) P90 Storm 7,174 cf 9,862 cf wgla.com DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 1 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 24 Q 25 = CIA = 10.28 3 Rip Rap (d50= 9" 3 0.069 CHECK VELOCITY 12.750 V = 0.9 27.162 vis 0.469 CHECK SHEAR STRESS 11.8 T= yds = 0.2 0.91 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d 0.5 -' ' B 24 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 2 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 36 Q 25 = CIA = 11.85 3 Rip Rap (d50= 9" 3 0.069 CHECK VELOCITY 18.750 V = 0.9 39.162 vis 0.479 CHECK SHEAR STRESS 17.5 T= yds = 0.2 0.91 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d 0.5 ��=III III II-'' B 36 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 3 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 34 Q 25 = CIA = 12.14 3 Rip Rap (d50= 9" 3 0.069 CHECK VELOCITY 17.750 V = 0.9 37.162 vis 0.478 CHECK SHEAR STRESS 16.6 T= yds = 0.2 0.91 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d 0.5 -' ' B 34 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 4 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 26 Q 25 = CIA = 17.23 3 Rip Rap (d50= 9") 3.00 0.61 0.069 CHECK VELOCITY 16.976 V = 1.0 29.858 vis 0.569 CHECK SHEAR STRESS 17.8 T= yds = 0.2 1.0 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1.1 I--1111- LINER III I��,J� d 0.6 -' ' B 26 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 5 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 35 Q 25 = CIA = 0.73 3 Rip Rap (d50= 9") 3.00 0.10 0.104 CHECK VELOCITY 3.530 V = 0.2 35.632 OK 0.099 CHECK SHEAR STRESS 0.8 T= yds = 0.0 0.2 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d O.I ��=III III II-'' B 35 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 6 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 74 Q 25 = CIA = 45.81 3 Rip Rap (d50= 9") 3.00 0.58 0.069 CHECK VELOCITY 43.929 V = 1.0 77.668 vis 0.566 CHECK SHEAR STRESS 45.9 T= yds = 0.2 1.0 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1.1 I--1111- LINER III I��,J� d 0.6 -' ' B 74 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 7 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 41 Q 25 = CIA = 26.08 3 Rip Rap (d50= 9" 3 0.069 CHECK VELOCITY 25.234 V = 1.0 44.731 vis 0.564 CHECK SHEAR STRESS 26.3 T= yds = 0.2 1.0111 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1.1 I--1111- LINER III I��,J� d 0.6 ��=III III II-'' B 41 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 8 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 26 Q 25 = CIA = 3.60 3 Rip Rap (d50= 9") 3.00 0.31 0.104 CHECK VELOCITY 8.348 V = 0.5 27.961 vis 0.299 CHECK SHEAR STRESS 3.8 T= yds = 0.1 0.5 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d 0.3 -' ' B 26 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 9 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 29 Q 25 = CIA = 2.04 3 Rip Rap (d50= 9") 3.00 0.21 0.104 CHECK VELOCITY 6.222 V = 0.4 30.328 vis 0.205 CHECK SHEAR STRESS 2.2 T= yds = 0.1 0.4 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d 0.2 -' ' B 29 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Forebay Design FOREBAY NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 10 Suncap 20176 6/23/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 45 Q 25 = CIA = 7.13 3 Rip Rap (d50= 9") 3.00 0.33 0.104 CHECK VELOCITY 15.177 V = 0.5 47.087 vis 0.322 CHECK SHEAR STRESS 7.2 T= yds = 0.1 0.5 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 3 :1 -' I -I I EZI I p I I -I I Ed I I. D 1 I--1111- LINER III I��,J� d 0.3 -' ' B 45 Liner Rip Rap (d50= 9") B DocuSign Envelope ID: CAD BO D52-F5C B-48B3-B354-86C BAD F E6A28 Suncap Level Spreader Design Calculations DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Level Spreader Design LEVEL SPREADER NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 1 Suncap 20176 5/3/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 92 Q 25 = CIA = 56.98 0 Concrete 12.50 0.23 0.015 CHECK VELOCITY 21.528 V = 2.7 92.468 vis 0.233 CHECK SHEAR STRESS 57.2 T= yds = 0.1 2.71 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 0 :1 -' I-II1=1I p I1=1I1=1II. D 1 LINER III I��,J� d o.2 =' ' B 92 Liner Smooth Concrete B DocuSign Envelope ID: CAD BOD52-F5CB-48B3-B354-86CBAD FE6A28 Level Spreader Design LEVEL SPREADER NUMBER: PROJECT NAME: PROJECT NO.: DATE: LOCATION: DESIGN STORM RETURN YR: APPROACH: INPUT DATA: Drainage Area, Bare Soil (Ac) Drainage Area, Grass (Ac) Drainage Area, Woods (Ac) Drainage Area, Impervious (Ac) "C" Value Bare Soil "C" Value Grass "C" Value Woods "C" Value for Paved Rainfall Intensity (in/hr) Ditch Slope (Decimal) Bottom Width (ft) Ditch Side Slope (x:1) SOLUTION: Try Type Allowable Shear Stress d guess (ft) n (no units) A (sqf) P (ft) R = A/P Q=L49/n(AR" 2/3)(S" l/2) Velocitv = O/A 2 Suncap 20176 5/3/2021 Town of Mills River, North Carolina 25 Use Trial & Error to set the flow depth, d, until Q = Q 25 0.4 (NCDENR Table 8.03b) 0.3 (NCDENR Table 8.03b) 0.2 (NCDENR Table 8.03b) 0.9 (NCDENR Table 8.03b) 8.08 NOAA Atlas 14, Volume 2, Version 3 0.005 DESIGN STORM: 122 Q 25 = CIA = 37.91 0 Concrete 12.50 0.15 0.015 CHECK VELOCITY 18.849 V = 2.0 122.309 OK 0.154 CHECK SHEAR STRESS 38.1 T= yds = 0.0 2.01 OK Allow. n Values for Depth Ranges: Manning n Shear Allow. Lining Type 0 - 0.5 ft 0.5 - 2.0 ft > 2 ft Stress Velocity Bare Soil (No Temp Liner) 0.020 0.020 0.020 N/A 2.5 fps NAG S 75 (Straw with Net) 0.055 0.038 0.021 1.55 5 fps NAG S 150 (Straw with Net) 0.055 0.038 0.021 1.75 6 fps NAG SC150 (Straw/Coconut) 0.050 0.034 0.018 2.00 8 fps NAG C 125 (Coconut with Net) 0.022 0.018 0.014 2.25 10 fps NAG P300 / Propex 450 0.034 0.027 0.200 8.00 16 fps Rip Rap (d50= 9") 0.104 0.069 0.035 3.00 4.5 fps Rip Rap (d50=12") --- 0.078 0.040 4.00 5 fps Smooth Concrete 0.015 0.013 0.013 12.50 40 fps Sod or Established Grass 0.033 0.030 0.030 N/A 4.5 fps FINAL DESIGN Side Slope 0 :1 -' I-II1=1I p I1=1I1=1II. D 1 �_- _ -ICII d 0.2 B 122 LINER - I I 111 I� I. Liner Smooth Concrete B