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HomeMy WebLinkAboutWPO202200013 Calculations 2022-11-14PREMIER CIRCLE VSH BUILDING (PHASE 1) ALBEMARLE COUNTY, VIRGINIA DESIGN CALCULATIONS & NARRATIVE WPO 2022-00013 JUNE 215 2022 00006 . • • TIMMONS GROUP YOUR VISION ACHIEVED THROUGH OURS. Prepared by: Jonathan Showalter, PE Timmons Group 608 Preston Avenue, Suite 200 Charlottesville, VA 22903 434.327.1681 Table of Contents Section Title Project Narrative HydroCAD Calculations 55 Virginia Runoff Reduction Method Worksheet 56 LD-204 Inlet Calculations 57 LD-229 Pipe Calculations 58 NRCS Web Soil Survey Map 78 NOAA Atlas 14 — Precipitation Frequency Estimate Table Project Narrative: This project included the removal of existing hotel buildings and associated hardscapes and utilities in order to construct a new building developed by Virginia Supportive Housing (VSH) for Phase 1 of the development. The future phases will have their own Final Site Plans and WPO plans submitted. These are currently planned as another multi- family building by Piedmont Housing Alliance (PHA) (Phase 2), and a commercial building to be developed by another developer (Phase 3). This first Phase 1 project will remove two of the existing hotel buildings and include the construction of the VSH building located in the middle of the parcel. Phase 2 will include the removal of the northern hotel building and include the construction of the PHA. Phase 3 will include the removal of the southern hotel building and include the construction of the commercial building. Each phase will have their own VSMP / WPO submitted for review and approval before construction. The current existing conditions will be used as the pre - developed condition for each future phase. The future overall anticipated limit of disturbance is 3.68 acres and will meet water quantity requirements through onsite detention and water quality requirements through the purchase of offsite nutrient credits. This WPO submission is for the construction of Phase 1 only and will only include calculations for phase 1 work. The limits of disturbance for phase 1 is 1.75 acres. In the existing conditions, there is 0.28 acres of pervious area and 1.47 acres of impervious area within the limits of disturbance and the existing pond is routed in the pre -developed calculations. In the proposed condition, there will be 0.95 acres of pervious area and 0.80 acres of impervious area. Water Ouality: The current site has four buildings with associated parking. For the master plan, 3.68 acres of disturbance was analyzed for water quality and will require approximately 1.14 lb./year to be treated. This will be finalized for review and purchase on future WPO/VSMP plans. For phase 1, two of the existing buildings will be removed along with their associated parking. Due to the decrease in impervious area from the existing conditions to the proposed conditions, no removal credit will be required for phase 1. Water Ouantity: The existing site is mostly impervious with buildings and parking lots. The Master Plan proposed development will have similar impervious cover. The majority of the site's runoff in the existing conditions is captured in an existing storm sewer system and conveyed to an existing stormwater facility located on the northeast comer of the site. In the final anticipated condition, the existing stormwater facility will be removed, and on -site detention will be satisfied through an underground storage pipe. In the final condition of phase 1, the existing stormwater facility will remain with a similar drainage area as the existing condition. In the existing conditions, the existing stormwater facility has a drainage area of approximately 3.34 acres and in the developed conditions will have a drainage area of 3.45 acres. Due to the decrease in impervious area from the pre -developed to post -developed conditions, the flow to the existing facility decreases and therefore will have capacity in the post -developed conditions. To satisfy the 9VAC-970-66.B stormwater requirement for channel protection, the energy balance equation was applied to the limits of disturbance for phase 1. Based on the equation, no additional detention is required beyond the existing stormwater management facility. To satisfy the 9VAC-970-66.0 stormwater requirement for flood protection, the post developed 10-year flow is less than the pre -developed 10-year flow for phase 1. 8S Preto P nd 9S A Pr Bypass Ex. Pon\ 24L AP Pre Subcat Reach Aon Llnk /15S To EPond Post 13S 7P BY PASS P T x. Pond 21L AP post PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CALCULATIONS Prepared by Timmons Group Printed 6/17/2022 Rainfall Events Listing Event# Event Storm Type Curve Mode Duration B/B Depth AMC Name (hours) (inches) 1 1-Year NOAA24-hr D Default 24.00 1 3.04 2 2 2-Year NOAA 24-hr D Default 24.00 1 3.68 2 3 10-Year NOAA 24-hr D Default 24.00 1 5.56 2 4 100-Year NOAA 24-hr D Default 24.00 1 9.14 2 4 PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CALCULATIONS Prepared by Timmons Group Printed 6/17/2022 Area Listing (selected nodes) Area CN Description (acres) (subcatchment-numbers) 4.130 98 (8S, 9S, 13S, 15S) 3.000 61 >75% Grass cover, Good, HSG B (8S, 9S, 13S, 15S) VA 1101CA W_1N=F_1 PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CALCULATIONS Prepared by Timmons Group Printed 6/17/2022 Soil Listing (selected nodes) Area Soil Subcatchment (acres) Group Numbers 0.000 HSG A 3.000 HSG B 8S, 9S, 13S, 15S 0.000 HSG C 0.000 HSG D 4.130 Other 8S, 9S, 13S, 15S 7.130 TOTAL AREA 3 PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CALCULATIONS Prepared by Timmons Group Printed 6/17/2022 Ground Covers (selected nodes) HSG-A HSG-B HSG-C HSG-D Other Total Ground Subcatchment (acres) (acres) (acres) (acres) (acres) (acres) Cover Numbers 0.000 0.000 0.000 0.000 4.130 4.130 8S, 9S, 13S, 15S 0.000 3.000 0.000 0.000 0.000 3.000 >75% Grass cover, Good 8S, 9S, 13S, 15S 0.000 3.000 0.000 0.000 4.130 7.130 TOTAL AREA PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CALCULATIONS Prepared by Timmons Group Printed 6/17/2022 Pipe Listing (selected nodes) Line# Node In -Invert Out -Invert Length Slope n Width Diam/Height Inside -Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 7P 468.36 467.66 5.0 0.1400 0.020 0.0 18.0 0.0 2 27P 468.36 467.66 5.0 0.1400 0.020 0.0 18.0 0.0 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 HydroCAD® 10.10-7a s/n 08663 © 2021 HydroCAD Software Solutions LLC Page 7 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment8S: Pre to Pond Runoff Area=3.340 ac 71.56% Impervious Runoff Depth>1.63" Tc=6.0 min CN=87 Runoff=6.71 cfs 0.454 of Subcatchment9S: Pre Bypass Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>0.38" Tc=6.0 min CN=63 Runoff=0.06 cfs 0.005 of Subcatchment13S: BY PASS POST Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>0.38" Tc=6.0 min CN=63 Runoff=0.06 cfs 0.005 of Subcatchment15S: To Ex. Pond Post Runoff Area=3.450 ac 49.86% Impervious Runoff Depth>1.10" Tc=6.0 min CN=79 Runoff=4.76 cfs 0.316 of Pond 7P: Ex. Pond Peak Elev=469.26' Storage=48 cf Inflow=6.71 cfs 0.454 of Outflow=6.71 cfs 0.454 of Pond 27P: Ex. Pond Peak Elev=469.07' Storage=8 cf Inflow=4.76 cfs 0.316 of Outflow=4.76 cfs 0.316 of Link 21 L: AP post Inflow=4.82 cfs 0.322 of Primary=4.82 cfs 0.322 of Link 24L: AP Pre Inflow=6.77 cfs 0.460 of Primary=6.77 cfs 0.460 of Total Runoff Area = 7.130 ac Runoff Volume = 0.781 of Average Runoff Depth = 1.32" 42.08% Pervious = 3.000 ac 57.92% Impervious = 4.130 ac PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 8S: Pre to Pond Runoff = 6.71 cfs @ 12.13 hrs, Volume= 0.454 af, Depth> 1.63" Routed to Pond 7P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 1-Year Rainfall=3.04" Area (ac) CN Description 2.390 98 0.950 61 >75% Grass cover, Good, HSG B 3.340 87 Weighted Average 0.950 28.44% Pervious Area 2.390 71.56% Impervious Area Tc Length Capacity Description 6.0 Direct Entry, Subcatchment 8S: Pre to Pond Hydrograph NOAA 24-hr D 6 1-Year Rainfall=3.04" 5 Runoff Area=3.340 'ac- Runoff Volume=0.454'af 4 Runoff Depth>1.63" Tc=6.0 min - 3 CN=;87 2 1 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 10 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 9S: Pre Bypass Runoff = 0.06 cfs @ 12.15 hrs, Volume= 0.005 af, Depth> 0.38" Routed to Link 24L : AP Pre Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 1-Year Rainfall=3.04" a (ac) CN Description 0.160 61 >75% Grass cover. Good. HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 9S: Pre Bypass Hydrograph 0 07 --�---T----�---T----- ❑Runoff o6 --------- NOAA 24-hr D 0.0 0.0 s 1-Year RainfallT3.04" ,___RuriffAm&O.17-0 c 0.05 0.045 __�___y____'____'____'__. L___I____ L___ J____L___ J____ Ku6o_ff- Vo1OjnO=O.005,,af - w 0.04 `V-' --r---,----I---T----I - I - - - -' r U-604De';0. th38-' 0.035 " = -- ---- --- ----10-nlirr- LL 0.03 I N= 1 0.025 r____I____ r___�___.i 0.02 I I I 9.915 I I I I 0.01 i I y 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 11 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 13S: BY PASS POST Runoff = 0.06 cfs @ 12.15 hrs, Volume= 0.005 af, Depth> 0.38" Routed to Link 21 L : AP post Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 1-Year Rainfall=3.04" Area (ac) CN Description 0.010 98 0.160 61 >75% Grass cover, Good, HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 13S: BY PASS POST Hydrograph 0 07 --�---T----�---T----- ❑Runoff 0.065- ooa --------- oa NOAA 24-hr D- 0.0s .0 1-Year Rai nfallT3.04'�- undFA�ea��.TTOc 0.05 0.045 L___J____ L___ J____L___ J____ Ru6o-ff- Vol0jn0=0.005;af__ w 0.04 r -- -' U-60ODe'th;0.38_ 0.035 " = -- ---- --- ----10-nlirr- u. 0.03 i N= 1 0.025 r____i____ r___�___.i 0.02 0.015 0.01 y 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 12 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 15S: To Ex. Pond Post Runoff = 4.76 cfs @ 12.13 hrs, Volume= 0.316 af, Depth> 1.10" Routed to Pond 27P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 1-Year Rainfall=3.04" Area (ac) CN Description 1.720 98 1.730 61 >75% Grass cover, Good, HSG B 3.450 79 Weighted Average 1.730 50.14% Pervious Area 1.720 49.86% Impervious Area Tc Length Slope Velocity Capacity Description 6.0 Direct Entry, Subcatchment 15S: To Ex. Pond Post Hydrograph 5 s crs NOAA 24-hr D 1-Year Rainfall=3.04" 4 Runoff Area=3.450 ac Runoff Volume=0.316 of 3- Runoff Depth>1.10" 0 Tc=6.0 min 2 CN=79 1 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 13 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 7P: Ex. Pond [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage [851 Warning: Oscillations may require smaller dt or Finer Routing (severity=36) Inflow Area = 3.340 ac, 71.56% Impervious, Inflow Depth > 1.63" for 1-Year event Inflow = 6.71 cfs @ 12.13 hrs, Volume= 0.454 of Outflow = 6.71 cfs @ 12.14 hrs, Volume= 0.454 af, Atten= 0%, Lag= 0.4 min Primary = 6.71 cfs @ 12.14 hrs, Volume= 0.454 of Routed to Link 24L : AP Pre Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 469.26' @ 12.14 hrs Surf.Area= 292 sf Storage= 48 cf Plug -Flow detention time= (not calculated: outflow precedes inflow) Center -of -Mass det. time= 0.0 min ( 787.8 - 787.8 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=6.48 cfs @ 12.14 hrs HW=469.24' (Free Discharge) 1=Culvert (Inlet Controls 4.69 cfs @ 4.36 fps) 2=Orif ice/G rate (Orifice Controls 1.79 cfs @ 3.28 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 14 PHASE 7 STORMWATER MANAGEMENT MASTER PWOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Pond 7P: Ex. Pond Hydrograph 6 71 ds 7 671cfs InflowArea=3.340_�c_ 6- Pea''k r'lev=4f9.g,6' 5 Stbrage,48 of I I I I 4 LL 3 i 2 I I I i 1 5 6 7 8 9 10 11 12 13 14 15 16 Time (houm) ■ Inflow ■ Primary 15 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 27P: Ex. Pond [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage Inflow Area = 3.450 ac, 49.86% Impervious, Inflow Depth > 1.10" for 1-Year event Inflow = 4.76 cfs @ 12.13 hrs, Volume= 0.316 of Outflow = 4.76 cfs @ 12.14 hrs, Volume= 0.316 af, Atten= 0%, Lag= 0.0 min Primary = 4.76 cfs @ 12.14 hrs, Volume= 0.316 of Routed to Link 21 L : AP post Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 469.07' @ 12.14 hrs Surf.Area= 138 sf Storage= 8 cf Plug -Flow detention time= 0.0 min calculated for 0.315 of (100% of inflow) Center -of -Mass det. time= 0.0 min ( 811.5 - 811.4 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 Primary OutFlow Max=4.66 cfs @ 12.14 hrs HW=469.07' (Free Discharge) 1=Culvert (Inlet Controls 3.23 cfs @ 3.92 fps) 2=Orif ice/G rate (Orifice Controls 1.42 cfs @ 2.87 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 16 PHASE 7 STORMWATER MANAGEMENT MASTER PWOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Pond 27P: Ex. Pond Hydrograph -d-]-6-ch---- --- 0Primary 4.Mds Inflp Ar a-3.450 ac - -- Peak-FCevi:44J 0,r - Storagp=8 pf 5 6 7 8 9 10 11 12 13 14 15 16 Time (houm) 17 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 21 L: AP post Inflow Area = 3.620 ac, 47.79% Impervious, Inflow Depth > 1.07" for 1-Year event Inflow = 4.82 cfs @ 12.14 hrs, Volume= 0.322 of Primary = 4.82 cfs @ 12.14 hrs, Volume= 0.322 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 21L: AP post Hydrograph Time (hours) FE ]—I n—fl.—w ❑ Primary 18 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 1-Year Rainfall=3.04" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 24L: AP Pre Inflow Area = 3.510 ac, 68.38% Impervious, Inflow Depth > 1.57" for 1-Year event Inflow = 6.77 cfs @ 12.14 hrs, Volume= 0.460 of Primary = 6.77 cfs @ 12.14 hrs, Volume= 0.460 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 24L: AP Pre Hydrograph Time (hours) FE ]—I n—fl.—w ❑ Primary 19 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 HydroCAD® 10.10-7a s/n 08663 © 2021 HydroCAD Software Solutions LLC Page 18 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment8S: Pre to Pond Runoff Area=3.340 ac 71.56% Impervious Runoff Depth>2.17" Tc=6.0 min CN=87 Runoff=8.78 cfs 0.603 of Subcatchment9S: Pre Bypass Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>0.65" Tc=6.0 min CN=63 Runoff=0.13 cfs 0.009 of Subcatchment13S: BY PASS POST Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>0.65" Tc=6.0 min CN=63 Runoff=0.13 cfs 0.009 of Subcatchment15S: To Ex. Pond Post Runoff Area=3.450 ac 49.86% Impervious Runoff Depth>1.55" Tc=6.0 min CN=79 Runoff=6.71 cfs 0.446 of Pond 7P: Ex. Pond Peak Elev=469.44' Storage=114 cf Inflow=8.78 cfs 0.603 of Outflow=8.71 cfs 0.603 of Pond 27P: Ex. Pond Peak Elev=469.26' Storage=48 cf Inflow=6.71 cfs 0.446 of Outflow=6.70 cfs 0.446 of Link 21 L: AP post Inflow=6.82 cfs 0.456 of Primary=6.82 cfs 0.456 of Link 24L: AP Pre Inflow=8.84 cfs 0.612 of Primary=8.84 cfs 0.612 of Total Runoff Area = 7.130 ac Runoff Volume = 1.068 of Average Runoff Depth = 1.80" 42.08% Pervious = 3.000 ac 57.92% Impervious = 4.130 ac 99 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 8S: Pre to Pond Runoff = 8.78 cfs @ 12.13 hrs, Volume= 0.603 af, Depth> 2.17" Routed to Pond 7P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.68" Area (ac) CN Description 2.390 98 0.950 61 >75% Grass cover, Good, HSG B 3.340 87 Weighted Average 0.950 28.44% Pervious Area 2.390 71.56% Impervious Area Tc Length Capacity Description 6.0 Direct Entry, Subcatchment 8S: Pre to Pond Hydrograph NOAA 24-hr D 8 2-Year Rainfall-3.618" 7 Runbff Area,=3.340 'ac 6 Runoff,Votume=0.601of w Runoff-Depths-117" 3 5 Tc=&G rain - 4 CN=;87- 2 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 21 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 9S: Pre Bypass Runoff = 0.13 cfs @ 12.14 hrs, Volume= 0.009 af, Depth> 0.65" Routed to Link 24L : AP Pre Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.68" a (ac) CN Description 0.160 61 >75% Grass cover. Good. HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc Length Slope Velocity Capacity Description Direct Entry, Subcatchment 9S: Pre Bypass Hydrograph I C I I � I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I NOAA 24-hr D 2-Year FRainfallT3.618" Runoff Area=0.170 'ac Runoff Volump=_0.009 af- Runoff Depth�'-0.85" -I �I' T�=6i0-rtlm I I I I I I I I N: 3- I --r---- I ---- r---I----r I r --- I I I I I I I I I I I I I I I I I I I I 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 22 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 13S: BY PASS POST Runoff = 0.13 cfs @ 12.14 hrs, Volume= 0.009 af, Depth> 0.65" Routed to Link 21 L : AP post Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.68" Area (ac) CN Description 0.010 98 0.160 61 >75% Grass cover, Good, HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc Length Capacity Description 6.0 Direct Entry, Subcatchment 13S: BY PASS POST Hydrograph 0.14 0.13 I I I I I C I 0.12 ' I I I I I � 0.11 I I I I I I I I I I I I I 0.1 I I I I I I 0.09 N 0.08 0.07 LL 0.06 0.05 I I I I I 004 0.03 0.02 0.01 NOAA 24-hr D 2-Year FRainfallT3.618" Runoff Area=0.170 lac Runoff Volllump=_0.�009114f- Runoff Depth�'-0.85" I I I I I I I I I N: 3- I -r---, ----r---I----r I r --- I I I I I I I I I I I I I 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 23 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 15S: To Ex. Pond Post Runoff = 6.71 cfs @ 12.13 hrs, Volume= 0.446 af, Depth> 1.55" Routed to Pond 27P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.68" Area (ac) CN Description 1.720 98 1.730 61 >75% Grass cover, Good, HSG B 3.450 79 Weighted Average 1.730 50.14% Pervious Area 1.720 49.86% Impervious Area Tc Length 2 0 F 5 Capacity Description Direct Entry, Subcatchment 15S: To Ex. Pond Post Hydrograph NOAA 24-hr D 2-Year Rainfall=3.68" Runoff Area=3.450 ac Runoff Volume=0.446 of Runoff Depth>1.55" Tc=6.0 min CN=79 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 24 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 7P: Ex. Pond [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage [851 Warning: Oscillations may require smaller dt or Finer Routing (severity=30) Inflow Area = 3.340 ac, 71.56% Impervious, Inflow Depth > 2.17" for 2-Year event Inflow = 8.78 cfs @ 12.13 hrs, Volume= 0.603 of Outflow = 8.71 cfs @ 12.14 hrs, Volume= 0.603 af, Atten= 1%, Lag= 0.5 min Primary = 8.71 cfs @ 12.14 hrs, Volume= 0.603 of Routed to Link 24L : AP Pre Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 469.44' @ 12.14 hrs Surf.Area= 441 sf Storage= 114 cf Plug -Flow detention time= (not calculated: outflow precedes inflow) Center -of -Mass det. time= 0.0 min ( 780.6 - 780.5 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=8.46 cfs @ 12.14 hrs HW=469.42' (Free Discharge) 1=Culvert (Inlet Controls 6.36 cfs @ 4.77 fps) 2=Orif ice/G rate (Orifice Controls 2.10 cfs @ 3.85 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 25 PHASE 7 STORMWATER MANAGEMENT MASTER PWOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Pond 7P: Ex. Pond Hydrograph I I I I I I I I ■ Inflow 8 78 ifs ii//��� ■ Primary 9 - - - 8.71 cfs — I nfk)w Area 3.3404c- - ---Peak-F,levi::4414lV - '---$iora"=1�14-ef_- , I 6 I I I I I v I I 5 I I I CS I C 4 ___ I I 3 i I I I 2 J ---' , 5 6 7 8 9 10 11 12 13 14 15 16 Time (houm) 9E PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 27P: Ex. Pond [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage [851 Warning: Oscillations may require smaller dt or Finer Routing (severity=36) Inflow Area = 3.450 ac, 49.86% Impervious, Inflow Depth > 1.55" for 2-Year event Inflow = 6.71 cfs @ 12.13 hrs, Volume= 0.446 of Outflow = 6.70 cfs @ 12.14 hrs, Volume= 0.446 af, Atten= 0%, Lag= 0.4 min Primary = 6.70 cfs @ 12.14 hrs, Volume= 0.446 of Routed to Link 21 L : AP post Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 469.26' @ 12.14 hrs Surf.Area= 291 sf Storage= 48 cf Plug -Flow detention time= (not calculated: outflow precedes inflow) Center -of -Mass det. time= 0.0 min ( 803.2 - 803.2 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=6.49 cfs @ 12.14 hrs HW=469.24' (Free Discharge) 1=Culvert (Inlet Controls 4.70 cfs @ 4.36 fps) 2=Orif ice/G rate (Orifice Controls 1.79 cfs @ 3.28 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 27 PHASE 7 STORMWATER MANAGEMENT MASTER PWOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Pond 27P: Ex. Pond Hydrograph ___ -____�_____________ ___ -____�____ �___--- ___� ___ �____ ■Inflow a fi]t ch �___ i� �APrimary T °° nfl-wrea=3.460-�c- Pea'k r;lev�4f9.Z6' -L-------L---J Stbrage,48 of 5 I 4 e LL 3 i 2 1 / 1 12 13 Time (houm) 28 PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 21 L: AP post Inflow Area = 3.620 ac, 47.79% Impervious, Inflow Depth > 1.51" for 2-Year event Inflow = 6.82 cfs @ 12.14 hrs, Volume= 0.456 of Primary = 6.82 cfs @ 12.14 hrs, Volume= 0.456 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 21L: AP post Hydrograph Time (hours) FE ]—I n—fl.—w ❑ Primary ME PHASE 1 STORMWATER MANAGEMENT MASTER PLIVOAA 24-hrD 2-Year Rainfall=3.68" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 24L: AP Pre Inflow Area = 3.510 ac, 68.38% Impervious, Inflow Depth > 2.09" for 2-Year event Inflow = 8.84 cfs @ 12.14 hrs, Volume= 0.612 of Primary = 8.84 cfs @ 12.14 hrs, Volume= 0.612 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 24L: AP Pre Hydrograph Time (hours) ■ Inflow ■ Primary 0 PHASE 1 STORMWATER MANAGEMENT MASTER P4LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 HydroCAD® 10.10-7a s/n 08663 © 2021 HydroCAD Software Solutions LLC Page 29 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment8S: Pre to Pond Runoff Area=3.340 ac 71.56% Impervious Runoff Depth>3.81" Tc=6.0 min CN=87 Runoff=14.94 cfs 1.061 of Subcatchment9S: Pre Bypass Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>1.68" Tc=6.0 min CN=63 Runoff=0.36 cfs 0.024 of Subcatchment13S: BY PASS POST Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>1.68" Tc=6.0 min CN=63 Runoff=0.36 cfs 0.024 of Subcatchment15S: To Ex. Pond Post Runoff Area=3.450 ac 49.86% Impervious Runoff Depth>3.03" Tc=6.0 min CN=79 Runoff=12.83 cfs 0.871 of Pond 7P: Ex. Pond Peak EIev=470.04' Storage=523 cf Inflow=14.94 cfs 1.061 of Outflow=14.11 cfs 1.061 of Pond 27P: Ex. Pond Peak EIev=469.81' Storage=330 cf Inflow=12.83 cfs 0.871 of Outflow=12.40 cfs 0.871 of Link 21 L: AP post Inflow=12.75 cfs 0.895 of Primary=12.75 cfs 0.895 of Link 24L: AP Pre Inflow=14.46 cfs 1.085 of Primary=14.46 cfs 1.085 of Total Runoff Area = 7.130 ac Runoff Volume = 1.979 of Average Runoff Depth = 3.33" 42.08% Pervious = 3.000 ac 57.92% Impervious = 4.130 ac 31 PHASE 1 STORMWATER MANAGEMENT MASTER P4LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 8S: Pre to Pond Runoff = 14.94 cfs @ 12.13 hrs, Volume= 1.061 af, Depth> 3.81" Routed to Pond 7P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 10-Year Rainfall=5.56" Area (ac) CN Description 2.390 98 0.950 61 >75% Grass cover, Good, HSG B 3.340 87 Weighted Average 0.950 28.44% Pervious Area 2.390 71.56% Impervious Area Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description 6.0 Direct Entry, Subcatchment 8S: Pre to Pond Hydrograph -------------'--------------'-------------=--------------------I---- G Runoff 16 I ___ __ __ -r -I id.9M1 CfE -I -T -r -r-r I T -J -L -I -1 -L -J ���III -I -L -L (, 14 I_ I_ I_ I_ I_ ----� ---� _ ---� _ ---, -- ---, - -, - 1-Yea rRainfalfrS6f6'�- ,3 1---- T ---- I ----T----r---1-__ __-�---TT-----r---l----rI7--/-- ,2 ' - ---Runbf Arecl-- V�It- „ I I I I I I ,0 Runoff:, Votl,ump=1.061'I,af ---,----T---- -------- ------ w .r 9 Runoff Depth?3.81., 3 8 i I I I I I I IL JI LL 7 ---,----T ,---- ---,- ----T----F- - -,------4rN=''87__ 5 4 I 3 2 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 32 PHASE 1 STORMWATER MANAGEMENT MASTER P4LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 9S: Pre Bypass Runoff = 0.36 cfs @ 12.14 hrs, Volume= 0.024 af, Depth> 1.68" Routed to Link 24L : AP Pre Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 10-Year Rainfall=5.56" a (ac) CN Description 0.160 61 >75% Grass cover. Good. HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity Description (cfs) 6.0 Direct Entry, Subcatchment 9S: Pre Bypass Hydrograph 0.38 I ____1----r----1----r----1----r--------r----1----r----1----r----r---r--- --------------- I I I ---------- I I I I I I I I I I ---I ------- --------' --------- ---- GRUnoff 0.36 -------'i I -------'i -------� I 0.3fi ofs 1 I I I I I -- ---�----------NOAA 2'4-hr�- 0.32 L , 1O-Year Rairria&5—.56"-- 0.3 ---J-------J----L---J----`-- --- `--_I----i--_I----i--__I----i---- 0.28 ---J----'�--- ---- --- ----�-- ---L--Runbff-Area-"7aac-- 0.26 ---J,----;�---J,----L---J,----�-- RUnoff�of;Um`=0.024,af-- 0.22 -- - ---Runof# Depth�-1.68` - LL 0.18 I I ___�____�___�____�___�____�-- I I I I I I I TI`� /� .�{ --------1----`----I__- t--6a0 -Min-- 0.16 0.14 - 1 PN=6,3 012 1 1 01 1 1 1 ------------1----1----r-------- r 0.06 81 _ -- 0.0 r ; 0.04 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 33 PHASE 1 STORMWATER MANAGEMENT MASTER PYLLOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 13S: BY PASS POST Runoff = 0.36 cfs @ 12.14 hrs, Volume= 0.024 af, Depth> 1.68" Routed to Link 21 L : AP post Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.56" Area (ac) CN Descriotion " 0.010 98 0.160 61 >75% Grass cover, Good, HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc (min) Length (feet) Slope (f /ft) Velocity (f /sec) Capacity (cfs) Description 6.0 Direct Entry, Subcatchment 13S: BY PASS POST Hydrograph 0.38 ____1----r----1----r----1----r--------r----1----r----1----r----r---r--- ___�________�________�----- 1 ___________________________________ ■Runoff 0.34 ----------- I I ----�--- I I ----�-- I 0.3fi ofs I I 1 -----------I---NO �1� 2I4-h r�- I I I I '?" I I I I I I I I I 0.32 ---�1---- IL --- �1---- L--- �1 ---- ; -- pI ,,�Is� //I�� C �Ic ---; --1 0-Year Rainf U:;5-..516"-- 0.3 0.28 ---J---- ---J----`--- ---J----`---J----L-- ----`--- ----`-- ---` ---I -- -i--_-II-_-w-.-L----I----i---- ---`--�iYnb f-/#� ai=&0170 aCr- - 0.24 ' I I I I I 1 1 Rurlioff 0117119 .0-------- 0.22 ' J1 --; --- '11-_Run_off_Depth:�1:Q8"-- 3 0.2 _ - -4 -- -4 Tt=&O -Mi 016 0.14 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 1 N= 3- _ 012 1 1 1 1 1 1 1 1 1 1 1 0.08 - - 10 11 12 13 14 15 16 17 18 10 20 Time (hours) c PHASE 1 STORMWATER MANAGEMENT MASTER P4LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 15S: To Ex. Pond Post Runoff = 12.83 cfs @ 12.13 hrs, Volume= 0.871 af, Depth> 3.03" Routed to Pond 27P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 10-Year Rainfall=5.56" Area (ac) CN Description 1.720 98 1.730 61 >75% Grass cover, Good, HSG B 3.450 79 Weighted Average 1.730 50.14% Pervious Area 1.720 49.86% Impervious Area Tc Length 14 13 12 11 Capacity Description Direct Entry, Subcatchment 15S: To Ex. Pond Post Hydrograph } NOAA 24-hr D 10-Year Rainfall=5.56" Runoff Area=3.450 ac Runoff Volume=0.871 of Runoff Depth>3.03" Tc=6.0 min ---- --- CN=79 7____ 7__. _7_. 7___- ___li__ 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ❑ Runoff 35 PHASE 1 STORMWATER MANAGEMENT MASTER P1LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 7P: Ex. Pond [821 Warning: Early inflow requires earlier time span [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage Inflow Area = 3.340 ac, 71.56% Impervious, Inflow Depth > 3.81" for 10-Year event Inflow = 14.94 cfs @ 12.13 hrs, Volume= 1.061 of Outflow = 14.11 cfs @ 12.15 hrs, Volume= 1.061 af, Atten= 6%, Lag= 1.2 min Primary = 14.11 cfs @ 12.15 hrs, Volume= 1.061 of Routed to Link 24L : AP Pre Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 470.04' @ 12.15 hrs Surf.Area= 938 sf Storage= 523 cf Plug -Flow detention time= 0.1 min calculated for 1.057 of (100% of inflow) Center -of -Mass det. time= 0.1 min ( 766.2 - 766.1 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=14.06 cfs @ 12.15 hrs HW=470.03' (Free Discharge) 1=Culvert (Inlet Controls 11.12 cfs @ 6.29 fps) 2=Orif ice/G rate (Orifice Controls 2.94 cfs @ 5.39 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 12 PHASE 7 STORMWATER MANAGEMENT MASTER Pr1LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Pond 7P: Ex. Pond Hydrograph ' ---'----'- -L---L----L-------'----'--------L-------L---J----L--- -- ■nflow I ___�____r___T____I____r____I ■Primary 16 ices ,6 --=- -----------T --- 'll- ------;.-„ds ---infllloWiArea=3.-340im 14 L P@Ak I Iev�::47r0.-N - 13 I I I I I I I I I I I I I I 12 ,- ' 1 ------------r---,- I 1 I I ----------- Sforag�=IS23-ef- „' I I I , I I I I I I I _ 10 IL _ ry� ' ___J____I____1 _I _J _I _1 _I _L _J _ u 9 �.a 1 3 a 0 1 I I I I I I iL 7 I I , 6 I ___-____I____y____I____i_ j ' I I 1 I I I 4 i , /[ 3 i ' I I 1 1 I ______ 1 1 I I 1 12 13 Time (horns) 37 PHASE 1 STORMWATER MANAGEMENT MASTER P1LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 27P: Ex. Pond [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage [851 Warning: Oscillations may require smaller dt or Finer Routing (severity=17) Inflow Area = 3.450 ac, 49.86% Impervious, Inflow Depth > 3.03" for 10-Year event Inflow = 12.83 cfs @ 12.13 hrs, Volume= 0.871 of Outflow = 12.40 cfs @ 12.15 hrs, Volume= 0.871 af, Atten= 3%, Lag= 0.9 min Primary = 12.40 cfs @ 12.15 hrs, Volume= 0.871 of Routed to Link 21 L : AP post Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 469.81' @ 12.15 hrs Surf.Area= 744 sf Storage= 330 cf Plug -Flow detention time= (not calculated: outflow precedes inflow) Center -of -Mass det. time= 0.1 min ( 786.8 - 786.7 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=12.28 cfs @ 12.15 hrs HW=469.79' (Free Discharge) 1=Culvert (Inlet Controls 9.64 cfs @ 5.55 fps) 2=Orif ice/G rate (Orifice Controls 2.64 cfs @ 4.85 fps) 3=Orif ice/G rate ( Controls 0.00 cfs) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) M PHASE 7 STORMWATER MANAGEMENT MASTER Pr1LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Pond 27P: Ex. Pond Hydrograph -------r--T r T r--------r -- ----------L-------L---'1283ok --L-------L---J----L--- 14 7 r AC13 Infow�Arma-0 2eo .45V 12 I'I---- „ I ----------i--- I 1 1 ---+I'- ---Qeakk_glev�4fIQV I I I I I I I I 91 I I I I _L _J _L __ 9 , I I I I I I I I I I I I I I I I I I ._. , I 7 0 , I I I I , I I I 6 , I I I I 5 I T - - - -r - I----r---T----r I I I I I I 4 I I I I I I I I I , I I I I I I I I I I I I I I I 5 6 7 8 9 10 11 12 13 14 Time (horns) ■ Inflow ■ Primary IE PHASE 1 STORMWATER MANAGEMENT MASTER P4LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 21 L: AP post Inflow Area = 3.620 ac, 47.79% Impervious, Inflow Depth > 2.97" for 10-Year event Inflow = 12.75 cfs @ 12.14 hrs, Volume= 0.895 of Primary = 12.75 cfs @ 12.14 hrs, Volume= 0.895 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 21L: AP post Hydrograph ❑ Inflow 0Primar 14 y msr 13 111iil��Ai*a=3.-62(Y c ___J____I____L___L____L___J_ 12 I I I I I I I I I I I I I I 10 I I I I I I I I 9 I I I I I I y8 I I I I I I I I I 7 I I I I I I I I I I I I _o LL I I I I I I I 5 I I I i I I I I I I I I I I I I I i I I I I I I I I I I I I 1 Time (hours) 4 40 PHASE 1 STORMWATER MANAGEMENT MASTER P1LOAA 24-hrD 10-Year Rainfall=5.56" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 24L: AP Pre Inflow Area = 3.510 ac, 68.38% Impervious, Inflow Depth > 3.71" for 10-Year event Inflow = 14.46 cfs @ 12.15 hrs, Volume= 1.085 of Primary = 14.46 cfs @ 12.15 hrs, Volume= 1.085 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 24L: AP Pre Hydrograph 18 ' --------------------- I I I I ---- ---,-- 14.46 cfs "°`ds Inflow Area=3.510 ac „ I I I I I I I 12 ' - - r---r---r--- I I ------r---r--- - ----f - 1 I I I 11 I I I I 1 I I I 1 8 LL 7 I____I____I 8 ' ' i I I I I 1 I I I I I 5 1 _____I____ 4 1 Time (hours) 4 ❑ Inflow ❑ Primary 41 PHASE 1 STORMWATER MANAGEMENT MASTER JW0AA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 HydroCAD® 10.10-7a s/n 08663 © 2021 HydroCAD Software Solutions LLC Page 40 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment8S: Pre to Pond Runoff Area=3.340 ac 71.56% Impervious Runoff Depth>7.03" Tc=6.0 min CN=87 Runoff=26.55 cfs 1.957 of Subcatchment9S: Pre Bypass Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>4.19" Tc=6.0 min CN=63 Runoff=0.89 cfs 0.059 of Subcatchment13S: BY PASS POST Runoff Area=0.170 ac 5.88% Impervious Runoff Depth>4.19" Tc=6.0 min CN=63 Runoff=0.89 cfs 0.059 of Subcatchment15S: To Ex. Pond Post Runoff Area=3.450 ac 49.86% Impervious Runoff Depth >6.11" Tc=6.0 min CN=79 Runoff=24.91 cfs 1.758 of Pond 7P: Ex. Pond Peak Elev=471.41' Storage=2,658 cf Inflow=26.55 cfs 1.957 of Outflow=21.90 cfs 1.957 of Pond 27P: Ex. Pond Peak Elev=471.20' Storage=2,232 cf Inflow=24.91 cfs 1.758 of Outflow=20.89 cfs 1.758 of Link 21 L: AP post Inflow=21.69 cfs 1.817 of Primary=21.69 cfs 1.817 of Link 24L: AP Pre Inflow=22.69 cfs 2.017 of Primary=22.69 cfs 2.017 of Total Runoff Area = 7.130 ac Runoff Volume = 3.834 of Average Runoff Depth = 6.45" 42.08% Pervious = 3.000 ac 57.92% Impervious = 4.130 ac 42 PHASE 1 STORMWATER MANAGEMENT MASTER JWOAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 8S: Pre to Pond Runoff = 26.55 cfs @ 12.13 hrs, Volume= 1.957 af, Depth> 7.03" Routed to Pond 7P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 100-Year Rainfall=9.14" Area (ac) CN Description 2.390 98 0.950 61 >75% Grass cover, Good, HSG B 3.340 87 Weighted Average 0.950 28.44% Pervious Area 2.390 71.56% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 8S: Pre to Pond Hydrograph -------+---- GRUnoff 28 2555 cfa 26 --NOAA 2'4-hS D 24400 Year Rairifailr9.44"-- 22 20 --- RunbfFArea=3.-340 ac- 1a Runoff Volume=1.957'aT- V 16 Runoff D"th;�,7.0_ 4 -- j--- --- T,c=6'60-MIM- L —~ 12 i___ __ 10 f N=,67 a 6 4 2 0 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 43 PHASE 1 STORMWATER MANAGEMENT MASTER 19'OAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 9S: Pre Bypass Runoff = 0.89 cfs @ 12.13 hrs, Volume= 0.059 af, Depth> 4.19" Routed to Link 24L : AP Pre Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 100-Year Rainfall=9.14" a (ac) CN Description 0.160 61 >75% Grass cover. Good. HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity Description (cfs) 6.0 Direct Entry, Subcatchment 9S: Pre Bypass Hydrograph 0.95 ■Runoff 0.9 T � F 089 cfs i i NOAA 24_fir-U- 0.8 �1---- ;IL --- �1---- L-1!1 ---;100-Yeiar RainfaU--;9A4'-'-- 0.75 0.7 ---L----L---L----L J - ---L--------L--------L----'----L---- ------Runoff-Area--O.Mac- 006 RuRoff- oCumQ' .0--9-af0.55 I I I---; ---RUnCif� Depth>4.1a0.5 ___�---------------- -----__�--__`---------yam045 i Fc=6.0 min040.35 __r___'i____r___'i____r___���_0.2502 0.15 --- ---- 0.1--------------r_______ - _____ r____r___r___ 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 44 PHASE 1 STORMWATER MANAGEMENT MASTER 19'OAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 13S: BY PASS POST Runoff = 0.89 cfs @ 12.13 hrs, Volume= 0.059 af, Depth> 4.19" Routed to Link 21 L : AP post Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 100-Year Rainfall=9.14" Area (ac) CN Description ' 0.010 98 0.160 61 >75% Grass cover, Good, HSG B 0.170 63 Weighted Average 0.160 94.12% Pervious Area 0.010 5.88% Impervious Area Tc (min) Length (feet) Slope (ft/ft) Velocity (ft/sec) Capacity (cfs) Description 6.0 Direct Entry, Subcatchment 13S: BY PASS POST Hydrograph 0.95 _ ________ _ ----________----------------------- ■Runoff 089 cfs 0.8 �1---- ;IL --- �1---- L-1!1 - ---;100-Yeiar Rainfal�T�1t4'-'-- 0.75 ---L----L---L----L - - ---L--------L--------L----'----L---- 0.7 ---J----'�--- ---- -- ------Runoff-Area--O.Mac- 006 RuRoff- oCumQ' .0--9-af0.55 I I I---; ---RUnCif� Depth>4.1a0.5 045 ___�----------------- -----__�--__`-------- i Tc=6.0 min040.35 _ __r___'i____r___'i____r___���_0.2502 0.15 - --- ---- 0.1--------------r_______ - _____ r____r___r___ 10 11 12 13 14 15 16 17 18 19 20 Time (hours) 45 PHASE 1 STORMWATER MANAGEMENT MASTER JWOAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Subcatchment 15S: To Ex. Pond Post Runoff = 24.91 cfs @ 12.13 hrs, Volume= 1.758 af, Depth> 6.11" Routed to Pond 27P : Ex. Pond Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hrD 100-Year Rainfall=9.14" Area (ac) CN Description 1.720 98 1.730 61 >75% Grass cover, Good, HSG B 3.450 79 Weighted Average 1.730 50.14% Pervious Area 1.720 49.86% Impervious Area Tc Length Capacity Description 6.0 Direct Entry, Subcatchment 15S: To Ex. Pond Post Hydrograph 26 24 22 20 I I 18 16 y 14 I I 3 LL 12 10 I I I 8 I I I I I I 6 I I I I I I I I I I I I 4 -I Y 2 I 0 F�f 5 6 10 i____ L___ J____ L___i____ i____ -DAfi'D- 00-Year Ralnfall9.14" ___Runbf_AreA3A5-acL _ ,71;af- - -Runof Dpth;>� ---T=8I-0r ---N1 9 y _ I _} Y T Time (hours) 17 18 19 20 ■ Runoff 46 PHASE 1 STORMWATER MANAGEMENT MASTER JWOAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 7P: Ex. Pond [821 Warning: Early inflow requires earlier time span [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage Inflow Area = 3.340 ac, 71.56% Impervious, Inflow Depth > 7.03" for 100-Year event Inflow = 26.55 cfs @ 12.13 hrs, Volume= 1.957 of Outflow = 21.90 cfs @ 12.17 hrs, Volume= 1.957 af, Atten= 18%, Lag= 2.9 min Primary = 21.90 cfs @ 12.17 hrs, Volume= 1.957 of Routed to Link 24L : AP Pre Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 471.41' @ 12.17 hrs Surf.Area= 2,094 sf Storage= 2,658 cf Plug -Flow detention time= (not calculated: outflow precedes inflow) Center -of -Mass det. time= 0.4 min ( 753.4 - 753.0 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=21.59 cfs @ 12.17 hrs HW=471.35' (Free Discharge) 1=Culvert (Inlet Controls 17.36 cfs @ 9.82 fps) 2=Orif ice/G rate (Orifice Controls 4.21 cfs @ 7.72 fps) 3=Orif ice/G rate (Orifice Controls 0.02 cfs @ 3.35 fps) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 47 PHASE 7 STORMWATER MANAGEMENT MASTER ROAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Pond 7P: Ex. Pond Hydrograph _-- _-------t--------*-------r--- 0Primary 2 ____________i--------r---y____r ---nf�wArea=�34Qbc- 26 I I 2 -I -- #3eclk ;lev"474.4-It - i i Zo I III-Storage=2s58_pf ---- _ 18 ___y____I____�____I____r___y_-__+_-------+--------r___y____r___ I I I I I I I I I ,u 18 / 1___J____L___J __J_ ____11 ___i_---i ___ i____i____ II II i i I I I I p 14 , I I I I I I I 12 ' ____I____I ____I __ ____I____ ____I____I I I I I I I I I I I I I I 10 , I I I I I I I I a ___ I____I ______ I I II I I II I I I , I I I I I I I I I I I a 1 12 13 Time (horns) 48 PHASE 1 STORMWATER MANAGEMENT MASTER JWOAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Pond 27P: Ex. Pond [821 Warning: Early inflow requires earlier time span [441 Hint: Outlet device #1 is below defined storage [441 Hint: Outlet device #2 is below defined storage [921 Warning: Device #5 is above defined storage Inflow Area = 3.450 ac, 49.86% Impervious, Inflow Depth > 6.11" for 100-Year event Inflow = 24.91 cfs @ 12.13 hrs, Volume= 1.758 of Outflow = 20.89 cfs @ 12.17 hrs, Volume= 1.758 af, Atten= 16%, Lag= 2.7 min Primary = 20.89 cfs @ 12.17 hrs, Volume= 1.758 of Routed to Link 21 L : AP post Routing by Stor-Ind method, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Peak Elev= 471.20' @ 12.17 hrs Surf.Area= 1,955 sf Storage= 2,232 cf Plug -Flow detention time= (not calculated: outflow precedes inflow) Center -of -Mass det. time= 0.3 min ( 769.0 - 768.6 ) Volume Invert Avail.Storage Storage Description #1 469.00' 14,632 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic -feet) (cubic -feet) 469.00 76 0 0 470.00 905 491 491 471.00 1,824 1,365 1,855 472.00 2,483 2,154 4,009 473.00 3,159 2,821 6,830 474.00 3,885 3,522 10,352 475.00 4,676 4,281 14,632 Device Routing Invert Outlet Devices #1 Primary 468.36' 18.0" Round Culvert L= 5.0' Ke= 0.100 Inlet / Outlet Invert= 468.36' / 467.66' S= 0.1400 '/' Cc= 0.900 n= 0.020 Corrugated PE, corrugated interior, Flow Area= 1.77 sf #2 Primary 468.36' 10.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 470.83' 1.0" W x 0.8" H Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #4 Primary 472.96' 2.0" x 2.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #5 Primary 475.00' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 1.00 Width (feet) 30.00 50.00 rimary OutFlow Max=20.58 cfs @ 12.17 hrs HW=471.14' (Free Discharge) 1=Culvert (Inlet Controls 16.53 cfs @ 9.35 fps) 2=Orif ice/G rate (Orifice Controls 4.04 cfs @ 7.40 fps) 3=Orif ice/G rate (Orifice Controls 0.01 cfs @ 2.53 fps) =Orif ice/G rate ( Controls 0.00 cfs) S=Custom Weir/Orifice ( Controls 0.00 cfs) 49 PHASE 7 STORMWATER MANAGEMENT MASTER ROAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Pond 27P: Ex. Pond Hydrograph � I I I I I I I I I I I I I TA.81 Cs I I 'il 26 — y -------'i I nflIIow;Ar-104.-00 aC 24 _____________J_________________-__________________ 1 1 I I I I I - - - --------i1 ---=----L ------ PeA1 kF1 Iev�1 47-2A' — 22 I I 11i 1 20 89 cfs 20 - -I--_1 tT-rafe L,--J- I I I 1 1 1 I I I I 16 -'---- L - -- J - - -- L--- 1 � i u I I I I 1 3 I 1 I c I I I 10 i i i i _I _+ —I —t —- _I —+ —I I I I I I I I I I 1 1 1 1 1 1 I I I 1 12 13 Time (horns) ■ Inflow ■ Primary 50 PHASE 1 STORMWATER MANAGEMENT MASTER JWOAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 21 L: AP post Inflow Area = 3.620 ac, 47.79% Impervious, Inflow Depth > 6.02" for 100-Year event Inflow = 21.69 cfs @ 12.17 hrs, Volume= 1.817 of Primary = 21.69 cfs @ 12.17 hrs, Volume= 1.817 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 21L: AP post Hydrograph - ---------- -------,-- 24 ------L---J----L---J __�__ z�.eees 2 �' _ _- - ------T--------r-Pt89 de L _ inflow Area=3.620 22 -------- I ac 2 18 ' • __i____I____ ___ i____i ___!____I____ I I I I I I I 17 13 ,2 -_-n----r---T----r---r---r -- ---r---T---- -r---r-------r--- „_J _L LL ,' I T -T -I -r -1 -r J____ L___ 8 T____I____T____I____r___r _____I____T____I____r___1____r___ 7 ___J____I____1___J____L___J 6 ___ y____I____ 7____I____r___ ,____I____ 7___ y____r___y____r___ 1 12 13 14 Time (hours) ❑ Inflow ❑ Primary 51 PHASE 1 STORMWATER MANAGEMENT MASTER JWOAA 24-hrD 100-Year Rainfall=9.14" Prepared by Timmons Group Printed 6/17/2022 Summary for Link 24L: AP Pre Inflow Area = 3.510 ac, 68.38% Impervious, Inflow Depth > 6.89" for 100-Year event Inflow = 22.69 cfs @ 12.17 hrs, Volume= 2.017 of Primary = 22.69 cfs @ 12.17 hrs, Volume= 2.017 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs Link 24L: AP Pre Hydrograph 2 221 24 ___T__ ________ ___ 3 ' 222 - - I 22 fi9 ci I I I 21 _--_____'____I____�___� ' I I I I I 12 LL 11 ,____T____I____r___r Qi - 8 7 8 5 —__l____I_ _- 1 Time (hours) Inflow Area=3.510 ac I -------- II I I I I I I I I I I I I I I I I 4 I _—_J____ L___ J____ L___ I ---- ---- L--- J____ L___ ------------------- _ _I---- L--- J _L T____ _ — ❑ Inflow ❑ Primary 52 PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CAbb/e of Contents Prepared by Timmons Group Printed 6/17/2022 TABLE OF CONTENTS Project Reports 1 Routing Diagram 2 Rainfall Events Listing 3 Area Listing (selected nodes) 4 Soil Listing (selected nodes) 5 Ground Covers (selected nodes) 6 Pipe Listing (selected nodes) 1-Year Event 7 Node Listing 8 Subcat 8S: Pre to Pond 9 Subcat 9S: Pre Bypass 10 Subcat 13S: BY PASS POST 11 Subcat 15S: To Ex. Pond Post 12 Pond 7P: Ex. Pond 14 Pond 27P: Ex. Pond 16 Link 21 L: AP post 17 Link 24L: AP Pre 2-Year Event 18 Node Listing 19 Subcat 8S: Pre to Pond 20 Subcat 9S: Pre Bypass 21 Subcat 13S: BY PASS POST 22 Subcat 15S: To Ex. Pond Post 23 Pond 7P: Ex. Pond 25 Pond 27P: Ex. Pond 27 Link 21 L: AP post 28 Link 24L: AP Pre 10-Year Event 29 Node Listing 30 Subcat 8S: Pre to Pond 31 Subcat 9S: Pre Bypass 32 Subcat 13S: BY PASS POST 33 Subcat 15S: To Ex. Pond Post 34 Pond 7P: Ex. Pond 36 Pond 27P: Ex. Pond 38 Link 21 L: AP post 39 Link 24L: AP Pre 100-Year Event 40 Node Listing 41 Subcat 8S: Pre to Pond 42 Subcat 9S: Pre Bypass 43 Subcat 13S: BY PASS POST 53 PHASE 1 STORMWATER MANAGEMENT MASTER PLAN ROUTING CAbb/e of Contents Prepared by Timmons Group Printed 6/17/2022 44 Subcat 15S: To Ex. Pond Post 45 Pond 7P: Ex. Pond 47 Pond 27P: Ex. Pond 49 Link 21 L: AP post 50 Link 24L: AP Pre 54 DELI Virginia Runoff Reduction Method Re-Developm 02012 LIMP Standards and Specifications 02013 Draft BMP Standards and Specifications Project Name: TIACH Premier Cirlce Phase 1 Date: 6/17/2022 Linear Development Project? No Site Information Post -Development Project (Treatment Volume and Loads) Enter Total Disturbed Area (acres) data Input cells constant values calculation cells Linearproject? No 5=71 Land cover areas entered correctly? ✓ r Total disturbed area entered? 5/ To LOAD REDUCTION NOT REQUIRED Pre-ReDevelopment Land Cover (acres( A soils BSoils Csoils DSoils recals Forest/Open Space (acres) -- undisturbed 0'� forest/open space Managed Tuff lacresl -- disturbed, graded for 0.28 yards or other turfto be mowed/managed 0.28 Impervious Caver(acres) 147 1.47 1.75 Post -Development Land Cover (acres( A Soils BSoils Csoils DSoils Totals Forest/Open Space(acres)-- undisturbaQ 0.00mtected forest/coor reforested land Managed Tuff (acres) - disturbed, graded for 0.95 yards or other turf to be mowed/man ed 0.95 Impervious Ueer(acres) 0.80 0.80 Area Check OK. OK. OK. OK. 1.75 Pre-ReDevelopment Listed Adjusted' Forest/Open Space Cancer (acres) 0.00 0.00 Weighted Rv(fimea) 0.00 0.00 %Forest Managed Tuff Cover (acres) 0.28 0.28 Weighted Rv(turf) 0.20 0.20 %Managed Tuff 16% 16% Impervious Cover (acres) 1.47 1.47 Rv(impervious) 0.95 0.95 %Impervious 84% 84% Total She Area (acres) 1.75 1.75 she Rv 0.83 0.83 Treatment Volume and Nutrient Load Pre-ReDevelopment Treatment Volume (acre -fit) 0.1210 0.1210 Pre-ReDevelopment Treatment Volume (cubicfeet) 5,273 5,273 Pre-ReDevelopment TP Load (Ib/yr) 3.31 3.31 PmRiDevelopmmn TP Load per acre (lb/acre/yr) 89 Baseline TP Load (IbIW) p0A1lbs/ave/yr applied to pre- redevelopment area erdudim pervious land imposed for new impervious cmreQ 072 'Adjusted Land Cover Summay: ore ReDevelopment land cover minus pervious lend cover (forenlopen spare or m raged turf) acreage proposedfor new impervious cover. adjusted total acreage is consistent with Post-ReDevelopment aaeops (minus ocreaye fnewierpervbuscover). ^obmn l shows bad reduction requnementf r new impervious cover (6asM on new levelopment load limit 0.41 Ihs/ocre/year). 0.95 Post Reopen. & New Impervious Fmest/Open Space 0.00 Cover Weighted Ranorest) 0.00 %Forest 0% Managed Tuff Cover 0.95 (acres) Weighted Rv(turf) 0.20 %Managetl Turf 54% Impervious Cover 0 Rai(impervious) 0.95 %Impervious 46% Final Site Area (acres) 1.75 Final Post Den Site Rv 0.54 Final Part - Development 0.0792 Treatment Volume (acre-ft) Final Past - Development 3,449 Treatment Volume (cubicfeet) Final Post- )evelopmentTPLoad 2.17 (lb/yr) 'inal Post -development TP Lead per arm T.za (lb/ave/yr) D Sall 0.05 0.25 0.95 Post-ReOevebpment Forest/Open Space Cover (acres) 000 Weighted Rvlforest) 0.00 %Forest 0% Managed Turf Cover (aats) 0.95 Weighted Be (turf) 0.20 %Managed Turf 54% ReDev. Impervious Cover (acres) 080 Re(impervious) 0.95 %Impervious 46% Total MO. site Area (acres) 1.75 ReDee Site Rv 0.54 Treatment Volume and Nutrient Load i d Reduction Required (Ib/yr) -0.48 Nitrogen Loads (Informational Purposes Only) Past-ReDevelopment TreatmentVolume 0.0792 (ecre-R) Post-ReDevelopment Treatmerh Volume 3A49 (Cubk feet) Port-ReDeveopment Wad (TP) 2.17 (lb/yr)a Post-ReDevelopment TP Load per acre (lb/acre/yr) Maz. Reduction Required (Below Pre- TO% Redevelopment Load) TP Load Reduction Required for Redeveloped Area 0'48 (Ib/Yrl Final Post -Development TN load Pre-ReDevelopment TN Load(lb/yr) 23.70 (Past-ReDevelopment&New 15.50 Impervious) (b/yr) Land Cover Summary -Post Past -Development New Impervious New Impervious Cover (acres) 0.00 e Rvlionervious) Port- Development Treatment Volume (ecra-Rl Port-DevelapmeM Trertmeat Volume (cubic eet) Post-DevelopmentID Wad (lb/yr) TP Load Reduction Required for New 0 .pervious Area (lb/vr) 55 FORM LO 201 STORMWATER INLET COMPUTATIONS SHEET 1 OF ROUTE PROJECT PREMIER CIRLCE DESIGNER: K.R GER DATE &17MM CHECKED: AMMEE UNITSAGUSH mmm�mmmomommmmmmaom®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmammmmmmm�mt®� ��m�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomom��mmo®om®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmm�mmmmmmmmmmm0mmmmmm®mt�m� ®mm�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomommmmmm®om®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmommmmmmm��m� ®�m�m®mmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomomm�mmm�om®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmommmmmmm�mm� ®�m�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomomm�mmm®om®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmommmmmmm�mtm� ��m�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomommmmmmmmmmmmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmm�mmmmmmmmmmmommmmmmm�mtm� m�m�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomommmmmmmmmmmmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmm®mmmmmmm�mtm� ®�m�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomommmmmmmmmmmmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmommmmmmm��m� ®�m�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mm�omommmmmmmmmmmmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmm®mmmmmmm�mtm ®�m�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomommmmmmmmmmmmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmm�mmmmmmmmmmm®mmmmmmm�mtm INLETSOFT RY ENSOFTEC DATE: W17Q= 56 LD-229 STORM SEWER DESIGN COMPUTATIONS STORM FREQUENCY 10 PROJECT: PREMIERCIRCLE LOCATION: ALBEMARLE COUNTY COUNTY: CharloVesville Desigrlell by: K BARGER Checked by: A. MABEE UNITS ENGLISH PIPE NO. FROMPoWT TO POWT DRAIN. AREA 'A' Acre 3 RUNOFF COEFF. C. C CA R Ef TOME M.W RAIN FALL IN B RUNOFF INVERT ELEVATIONS LENGTH of Pipe FL 12 SLOPE FIXI U SIZE (D-(X SpN14tt) a I< SHAPE Number of Pipes Ce iry CFS IS Friction Slole FUFL NORMAL FLOW FLOW TIME REMARK$ IS WORE- NEW 5 ACCUM- ULATEO 6 L nd CFS ToW Q CFS 9 UPPER END 10 LOWER END II Deplbof FIow,M FL Areeof FIow,An S9Ft H. FL Vn Ft S 16 En FL MCRE- ME. Mmut s 17 ACCUAIU -LAIID M.1cs 1 REFERENCE 1 STA. REFERENCE 2 STA 105 IN IN 061 082 050 081 662 605 00] 488 07193 <70.10 W91 003WC 12 Circular 1 669 0016M 063 053 029 930 198 0.11 6.T3 107 108 IN 003 037 001 030 5W 652 00] 198 CR 76 472 SO 2307 001127 12 Circular 1 4.10 OC@70 049 039 025 5.17 091 007 5.15 109 110 IN 000 000 029 5W 654 00] 199 OT3.71 47286 4267 001992 10 Circular 1 335 OCM70 045 030 0M 634 107 0.11 5.It III 112 110 002 OW 002 0% 5.85 629 0W 0CC 47439 47381 28.85 0=10 6 Circular 1 086 0WSW 025 0.10 0.13 4<3 0.56 0.11 595 113 IIA 112 0M 0.88 0M 005 567 633 0W 033 47556 tlA69 43.IN 001984 6 Circular 1 086 OW310 0M 009 0.11 AW 047 0.is 5.85 115 116 116 001 040 ON 002 5.35 557 ON U.11 47680 47566 57M 002W0 6 Circular 1 086 0M30 0.12 0M 007 301 026 032 567 II] 118 116 003 037 001 001 SW 557 OW 007 C77.91 tl6W 52.0 001995 6 Circular 1 086 OCW IO 0.10 003 0W 268 021 032 532 121 122 106 001 0Q 0W OW 500 650 OW OW 07591 <R03 19571 001998 6 Circular 1 086 OCWCO 0W 001 OOC 202 0.12 IQ 662 161 102 Jim 024 060 014 014 500 65C OW 09G 4108 <70.99 3628 0OI 12 Circular 1 669 OW](L 025 0.16 015 602 082 0.10 5.10 a 1 102 152 0.71 0.91 059 0n ill 502 OW 3.93 16928 468.71 15493 0W368 21 Circular 1 IOCI OW]50 073 0% 039 OW 098 065 5.75 57 USDA United States Department of Agriculture MRCS Natural Resources Conservation Service A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Albemarle County, Virginia FebruajN, 2022 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrGs.usda.govtwps/ portal/nres/main/soils/healthn and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https:Hoffices.sc.egov.usda.gov/locator/app?agency=nres) or your NRCS State Soil Scientist (http://www.nrGs.usda.govtwps/portal/nres/detail/soils/contactus/? cid=nres 142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 59 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 60 Contents Preface............................................................................ How Soil Surveys Are Made ......................................... SoilMap.......................................................................... SoilMap....................................................................... Legend......................................................................... MapUnit Legend.......................................................... Map Unit Descriptions.................................................. Albemarle County, Virginia ....................................... 2713—Elioak loam, 2 to 7 percent slopes .............. 27C—Elioak loam, 7 to 15 percent slopes..........., 34D—Glenelg loam, 15 to 25 percent slopes....... 39E—Hazel loam, 25 to 45 percent slopes.......... 88—Udorthents, loamy, 2 to 25 percent slopes.... 91—Urban land ..................................................... References..................................................................... ................ 2 ................5 ................ 8 ................9 ..............10 .............. 11 ...............11 ..............13 .............. 13 .............. 14 ..............15 ..............16 .............. 17 .............. 17 ..............19 4 61 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil -vegetation -landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 62 Custom Soil Resource Report scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil -landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil -landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field -observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and 6 63 Custom Soil Resource Report identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. 7 64 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 65 \ 406 !w r 4 27C i► 34D "' •} %lalth Cit 4 Y /Al. AP yeF 1� MAPLEGEND Area of Interest (AOO 0 Area of Interest (AOI) Solis Soil Map Unit Polygons N Soil Map Unit Lines Soil Map Unit Points Special Point Features V Blowout ® Borrow Pit Clay Spot O Closed Depression Gravel Pit Gravelly Spot O Landfill A. Lava Flow Marsh or swamp Mine or Quarry O Miscellaneous Water O Perennial Water y Rock Outcrop + Saline Spot Sandy Spot Severely Eroded Spot Q Sinkhole Slide or Slip J, Sodic Spot Custom Soil Resource Report MAP INFORMATION g Spoil Area The soil surveys that comprise your AOI were mapped at 1:15,800. o Stony Spot W Very Stony Spot Warning: Soil Map may not be valid at this scale. wet Spot Enlargement of maps beyond the scale of mapping can cause Other misunderstanding of the detail of mapping and accuracy of soil Special Line Features line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed Water Features scale. Streams and Canals Transportation Please rely on the bar scale on each map sheet for map �..ry Rails measurements. N Interstate Highways Source of Map: Natural Resources Conservation Service ti US Routes Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Major Roads Local Roads Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts Background distance and area. A projection that preserves area, such as the . Aerial Photography Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Albemarle County, Virginia Survey Area Data: Version 15, Sep 13, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 8, 2020--Sep 23, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. 10 67 Custom Soil Resource Report Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 27B Elioak loam, 2 to 7 percent slopes 7.8 33.6% 27C Elioak loam, 7 to 15 percent slopes 6.5 28.1% 34D Glenelg loam, 15 to 25 percent slopes 2.4 10.5% 39E Hazel loam, 25 to 45 percent slopes 0.6 2.6% 88 Udorthents, loamy, 2 to 25 percent slopes 2.7 11.5% 91 Urban land 3.2 13.8% Totals for Area of Interest 23.2 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it 11 68 Custom Soil Resource Report was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha -Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha -Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. 12 69 Custom Soil Resource Report Albemarle County, Virginia 2713—Elioak loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: kb8y Elevation: 360 to 790 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Elioak and similar soils: 80 percent Estimates are based on observations, Description of Elioak descriptions, and transects of the mapunit. Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from mica schist Typical profile H1 - 0 to 8 inches: loam H2 - 8 to 39 inches: silty clay H3 - 39 to 79 inches: silt loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat) (0.20 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: B Hydric soil rating: No 13 70 Custom Soil Resource Report 27C—Elioak loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: kb8z Elevation: 340 to 820 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Farmland of statewide importance Map Unit Composition Elioak and similar soils: 80 percent Estimates are based on observations, Description of Elioak descriptions, and transects of the mapunit. Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from mica schist Typical profile H1 - 0 to 8 inches: loam H2 - 8 to 39 inches: silty clay H3 - 39 to 79 inches: silt loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat) (0.20 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Hydric soil rating: No 14 71 Custom Soil Resource Report 34D—Glenelg loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: 2w061 Elevation: 30 to 1,200 feet Mean annual precipitation: 34 to 46 inches Mean annual air temperature: 43 to 66 degrees F Frost -free period: 174 to 211 days Farmland classification: Farmland of statewide importance Map Unit Composition Glenelg and similar soils: 90 percent Estimates are based on observations, Description of Glenelg descriptions, and transects of the mapunit. Setting Landform: Hillslopes Landform position (two-dimensional): Shoulder, backslope Landform position (three-dimensional): Side slope Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from mica schist Typical profile Ap - 0 to 6 inches: loam Bt - 6 to 23 inches: loam C - 23 to 65 inches: loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water (Ksat) (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Moderately high to high Available water supply, 0 to 60 inches: Very high (about 13.5 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B Hydric soil rating: No 15 72 Custom Soil Resource Report 39E—Hazel loam, 25 to 45 percent slopes Map Unit Setting National map unit symbol: 2yfh2 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Hazel and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Hazel Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from graywacke sandstone and mica schist Typical profile A - 0 to 10 inches: loam Bw - 10 to 20 inches: loam C - 20 to 30 inches: channery loam R - 30 to 79 inches: bedrock Properties and qualities Slope: 25 to 45 percent Depth to restrictive feature: 20 to 40 inches to lithic bedrock Drainage class: Excessively drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.20 to 5.95 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water supply, 0 to 60 inches: Low (about 4.1 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 7e Hydrologic Soil Group: B Hydric soil rating: No 16 73 Custom Soil Resource Report 88—Udorthents, loamy, 2 to 25 percent slopes Map Unit Setting National map unit symbol: 2xxz3 Elevation: 360 to 1,540 feet Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Udorthents and similar soils: 85 percent Minor components: 5 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Udorthents Setting Landform: I nterfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Convex Across -slope shape: Convex Parent material: Residuum weathered from granite and gneiss Properties and qualities Slope: 2 to 25 percent Depth to restrictive feature: More than 80 inches Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Minor Components Hatboro, occasionally flooded Percent of map unit: 5 percent Landform: Flood plains Down -slope shape: Linear Across -slope shape: Linear Hydric soil rating: Yes 91—Urban land Map Unit Setting National map unit symbol: kbg5 17 74 Custom Soil Resource Report Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost -free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Urban land: 85 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Urban Land Setting Landform: Interfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down -slope shape: Linear Across -slope shape: Linear Parent material: Residuum weathered from granite and gneiss Typical profile H1 - 0 to 6 inches: variable H2 - 6 to 79 inches: variable Properties and qualities Slope: 0 to 25 percent Depth to restrictive feature: 10 inches to densic material Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Very low to high (0.00 to 13.04 in/hr) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8s Hydric soil rating: No 18 75 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep -water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nres.usda.govAvps/portal/ nres/deta i I/nations I/soi Is/?cid=n res 142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www. nres.usda.gov/wps/portal/nres/detail/national/soils/?cid=nresl42p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www. nres.usda.gov/wps/portal/nres/detail/national/soils/?cid=nres142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nres.usda.gov/wps/portal/nres/detail/soils/ home/?cid=nres 142 p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nres.usda.gov/wps/portal/nres/ detail/national/landuse/rangepasture/?cid=stelprd b1043084 19 76 Custom Soil Resource Report United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nres.usda.gov/wps/portal/ nres/detail/soils/scientists/?cid=nres 142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. hftp://www.nres.usda.gov/wps/portal/nres/detail/national/soils/? cid=n res 142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/lnternet/FSE—DOCUMENTS/nrcsl42p2_052290.pdf 20 77 319/22, 12:46 PM Precipitation Frequency Data Server NOAA Atlas 14, Volume 2, Version 3 CHARLOTTESVILLE 1 SW Station ID: 44-1598 V Location name: Charlottesville, Virginia, USA* Latitude: 38.0333*, Longitude:-78.5167* Elevation: Elevation (station metadata): 541 ft** 'source: ESRI Maps ** source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Pa2ybok, 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 Average recurrence interval (years) Duration 7 2 5 10 25 50 1 100 00 200 500 1000 0.352 0.420 0.492 0.553 0.623 0.677 0.727 0.774 0.831 0.877 5-min (0.317-0.391) (0.379-0.466) (0.443-0.546) (0.497-0.612) (0.557-0.687) (0.602-0.746) (0.643-0.801) (0.681-0.853) (0.723-0.919) (0.756-0.973) 0.563 0.671 0.788 0.884 0.992 1.08 1.16 1.23 1.32 1.38 10-min (0.507-0.625) (0.605-0.745) (0.710-0.874) (0.794-0.979) (0.887-1.10) (0.959-1.19) 1 (1.02-1.27) 1 (1.08-1.35) 1 (1.14-1.45) 1 (1.19-1.53) 0.703 0.844 0.897 1.12 1.26 1.36 1.46 1.55 1.66 1.73 15-min (0.634-0.781) (0.761-0.937) (0.898.1.11) 1 (1.00-1.24) 1 (1.13-1.39) 1 (1.22-1.50) 1 (1.29-1.61) 1 (1.36-1.71) 1 (1.44-1.83) 1 (1.50-1.92) 0.964 1.17 1.42 1.62 1.86 2.06 2.24 2.41 2.63 2.81 30-min (0.869-1.07) 1 (1.05-1.29) 1 (1.27-1.57) 1 (1.46-1.79) 1 (1.67-2.06) (1.83-2.27) (1.98-2.46) (2.12-2.66) (2.29-2.91) (2.42-3.11) 60-min 2874 455 1.08-21034 1.324.62 1.64 2?01 1.90-12.34 2. 2 2.48 3507 2.733839 2.9733.73 3. 9-4.18 3. 3 1.44 1.75 2.19 2.57 3.07 3.47 3.90 4.33 4.94 5.45 2-hr (1.27-1.65) (1.54-2.00) (1.92-2.50) (2.26-2.93) (2.67-3.48) (3.01-3.94) (3.36-4.41) (3.704.90) (4.18-5.59) (4.56-6.19) 3.80 4.75 3-hr 1.38---1.82 1.67 2?20 2.09 2076 2.443 22 2. 0 3583 3. 84.34 3. 5 4787 4.045 42 4.54 6219 4.97 6885 6-hr 2.02 (1.79-2.29) 2.44 (2.15-2.76) 3.04 (2.67-3.43) 3.57 (3.13-4.03) 4.29 (3.744.84) 4.92 (4.25-5.53) 5.58 (4.78-6.27) 6.29 (5.33-7.08) 7.30 (6.10-8.22) 8.18 (6.74-9.23) 2.54 3.07 3.83 4.53 5.52 6.39 7.33 8.37 9.90 11.3 12-hr (2.25-2.92) (2.71-3.51) (3.374.38) (3.97-5.17) (4.79-6.27) (5.49-7.25) (6.23-8.32) (7.02-9.48) (8.14-11.2) (9.12-12.8) 24-hr 3.04 (2.743.41) 3.68 (3.324.12) 4.71 (4.22-5.26) 5.57 (4.98-6.20) 6.84 (6.07-7.59) 7.93 (6.99-8.79) 9.14 (7.99-10.1) 10.5 (9.05-11.6) 12.5 (10.6-13.8) 14.2 (11.9-15.6) 3.59 4.35 5.53 6.51 7.92 9.11 10.4 11.8 13.8 15.5 2-day (3.22-4.01) (3.914.86) (4.96-6.17) (5.81-7.25) (7.02-8.80) (8.01-10.1) (9.07-11.5) (10.2-13.1) (11.8-15.4) (13.1-17.3) 3-day 3.47-4.23 4.215312 (5.34 6851) (6. 5-97 63 7. 6 927 (8.63--610.6) 9: 6- 2.1) 11.0-13.8 (127-16.2) (14116- 8.2) 4.05 4.91 6.24 7.32 8.90 10.2 11.6 13.2 15.4 17.3 4-day (3.73-4.45) (4.51-5.39) (5.72-6.84) (6.70-8.01) (8.10-9.73) (9.24-11.2) (10.5-12.7) (11.8-14.4) (13.6-16.9) (15.1-19.1) 7-day 4.345'12 5.236717 6. 2-07971 7.57 8597 9. 5-910.8 10.3- 2.3 11.5-13.9 12.8- 5.7 14.17---18.2 16.13- 0.4 5.34 6.41 7.91 9.14 10.9 12.3 13.7 15.3 17.6 19.4 10-0ay (4.94-5.76) (5.93-6.92) (7.32-8.54) (8.43-9.85) (9.97-11.7) (11.2-13.2) (12.5-14.8) (13.8-16.6) (15.7-19.0) (17.1-21.1) 7.01 8.36 10.1 11.5 13.3 14.8 16.3 17.8 19.9 21.5 20-day (6.58-7.49) (7.85-8.94) (9.46-10.8) (10.7-12.2) (12.4-14.2) (13.7-15.8) (15.1-17.4) (16.4-19.1) (18.1-21.3) (19.5-23.1) 30tlay 8.60 (8.11-9.14) 10.2 (9.61-10.8) 12.1 (11.4-12.8) 13.5 (12.7-14.3) 15.3 (14.4-16.3) 16.7 1 (15.7-17.8) 18.1 1 (16.9-19.2) 19.5 (18.1-20.7) 21.2 (19.6-22.7) 22.6 (20.8-24.1) 10.7 12.7 14.8 16.4 18.5 20.0 21.5 22.9 24.7 2B.0 45rlay (10.2-11.4) (12.0-13.4) (14.0-15.7) (15.5-17.4) (17.4-19.5) 1 (18.8-21.2) 1 (20.1-22.7) 1 (21.4-24.3) 1 (23.0-26.3) 1 (24.1-27.8) 60day 12.6 14.8 17.1 18.8 21.0 22.6 24.1 25.6 27.4 28.8 (12.o-13.3) (14.1-15.6) (16.2-18.o) (17.8-19.8) (19.9-2.1) (21.3-23.8) (22.7-25.4) (24.0-27.0) (25.7-29.0) 11 (26.8.30.5) 1 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. Backto Top PF graphical 78 https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?st=va&sta=44-1598&data=depth&units=english&series=pds 1/4 319/22, 12:46 PM Precipitation Frequency Data Server Lim 25 c L 21 y 10 a c j nt PDS-based depth -duration -frequency (DDF) curves Latitude: 38.0333",Longitude: -78.51670 C C C C C T TT T T T T TT Eh E _ E J= J= J= L L re re re N re r0 r0 re N c rry A k6 r� N d � mo v vr�i a rE .. .: N .. iv o Duration WA L 21 I Average recurrence interval (years) NOAA Atlas 14, Volume 2, Version 3 Created (GMT): Wed Mar 9 17-45:55 2022 Back to Top Maps & aerials Small scale terrain Average recurrence interval (years) — 1 2 — 5 10 25 50 100 200 500 1000 Duration — 5-mm — 2-day — 10min — 3-day 15-min — 4-091y — 30-min — 7-day — 60-min — 10-0ay — 2fir — 20-day — 3fir — 30-day — "r — 45-day — 12fir — 60-day — 24fir 79 hftps://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?st=va&sta=44-1598&data=depth&units=english&series=pds 2/4 319/22, 12:46 PM IWFY am i eo Precipitation Frequency Data Server F .• Pen, Pa rk 'CharlottwOi11 Large scale terrain Washington, D.C.'` • Hi Harr isort6un7 • taunton _I�VIRGINIA IA Richr • • �L nrhburq `y 100km / N nrfn Large scale map An Nlashin{Iron Ri ch mo ynchhur0 + Blackehurp p o0^oke j o j _ 100km r I �� / Norh 6 r Large scale aerial 80 hftps://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?st=va&sta=44-1598&data=depth&units=english&series=pds 3/4 319/22, 12:46 PM Precipitation Frequency Data Server Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer 81 hftps://hdsc.nws.noaa.gov/hdsclpfds/pfds_printpage.html?st=va&sta=44-1598&data=depth&units=english&series=pds 4/4