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Home My WebLink AboutSDP201300008 Calculations 2013-01-17 County of Albemarle Virginia Engineering Manual For New Hope Church Erosion Control & Drainage Calculations First Submittal: January 17, 2013 ,4cpLTH Op Lr p Vi ND H. 2 ,. Lic.No.O'3831 4, 1�1?i/3 X44' SSIONAL 046 Blackwell Engineering PLC 03 566 East Market Street Harrisonburg, VA 22801 Ph. (540)432-9555 Fax(540)434-7604 Blackwellengineenng.cam BE# 2167 Table of Contents Description Page Erosion Control Narrative 1-6 Structure Sizing Calculations VDOT LD-229 7 VDOT LD-347 (Omitted— See Underground Detention Routing) VDOT LD-204 8 Nyloplast Inlet Chart 9 Pre- and Post-Construction Runoff Calculations 10-15 Underground Detention Routing 16-27 Inlet and Ditch Runoff Calculations 28-30 Ditch Calculations 31-37 Culvert Calculations 38-39 Outlet Protection Chart 40 Bioretention Basin Sizing Calculations 41 Sediment Trap Calculations 42 Drainage Map End EROSION & SEDIMENT CONTROL NARRATIVE PROJECT DESCRIPTION The purpose of this project is the mass grading for all phases of construction of the New Hope Church, entrance drive, parking lot and building for Phase 1. The site is located in Albemarle County, west of Route 29 and north of the intersection of Dickerson Lane and Dickerson Road. Phase 1 of the site will consist of a 200-seat church building and adjacent parking. A total of 3.8 acres will be disturbed during construction. EXISTING SITE CONDITIONS The site is tree-covered with two grass-covered clearings for overhead electric power lines. The land slopes to both the east and west at slopes ranging from 5% to 20% from a ridgeline that runs through the middle of the site at. ADJACENT PROPERTY An two existing churches and a preschool abuts the property to the east, Dickerson Road and Dickerson Lane to the south, Piney Mountain road to the west and residential land to the north. OFF-SITE AREA If material is imported to or exported from the site the Contractor will coordinate with the County ESC Administrator as to the location of the offsite fill/borrow area. The offsite fill/borrow area shall have a valid Land Disturbing Permit. SOILS 47C—Louisburg sandy loam, 7 to 15 percent slopes Map Unit Composition Louisburg and similar soils: 75 percent Properties and qualities Depth to restrictive feature: More than 80 inches Drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): High to very high(5.95 to 19.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water capacity: Moderate (about 6.6 inches) Interpretive groups Hydrologic Soil Group: B 1 Typical profile *sir.- 0 to 5 inches: Sandy loam Kw=0.24 T=3 5 to 79 inches: Sandy loam Kw=0.24 65C—Pacolet sandy loam, 7 to 15 percent slopes Map Unit Composition Pacolet and similar soils: 80 percent Properties and qualities Depth to restrictive feature: More than 80 inches Drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water capacity: Moderate (about 7.6 inches) Interpretive groups Hydrologic Soil Group: B Typical profile 0 to 6 inches: Sandy loam Kw=0.20 T=3 6 to 32 inches: Clay Kw=0.28 32 to 79 inches: Sandy clay loam Kw=0.28 94C—Wedowee sandy loam, 7 to 15 percent slopes `"'`"' Map Unit Composition Wedowee and similar soils: 80 percent Properties and qualities Depth to restrictive feature: More than 80 inches Drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water capacity: Moderate(about 8.0 inches) Interpretive groups Hydrologic Soil Group: B Typical profile 0 to 7 inches: Sandy loam Kw=0.24 T=3 7 to 11 inches: Sandy clay loam Kw=0.28 11 to 30 inches: Clay Kw=0.28 30 to 60 inches: Sandy clay loam Kw=0.28 2 CRITICAL EROSION AREAS New- The areas of critical slopes greater than 25% are identified by shading and labeling on the site plan. A small area of critical slopes is effected by grading for the drive entrance to the site. EROSION & SEDIMENT CONTROL MEASURES Unless otherwise indicated, all vegetative and structural erosion and sediment control practices shall be constructed and maintained according to the minimum standards and specifications of the Virginia Erosion and Sediment Control Regulations, latest edition. The minimum standards of the handbook shall be adhered to unless otherwise waived or approved by a variance. STRUCTURAL PRACTICES 1. Temporary Construction Entrance—3.02 A temporary construction entrance shall be installed as shown on the plans. During muddy conditions, drivers of construction vehicles shall be required to clean off their wheels before entering the highway. Runoff created during this procedure shall pass through an approved sediment removing process. 2. Construction Road Stabilization—3.03 A 6" course of VDOT #5 coarse aggregate shall be installed immediately after 'sow grading for entrance, drive, and parking. 3. Silt Fence—3.05 A temporary sediment barrier constructed of posts, filter fabric and, in some cases, a wire support fence, shall be installed where shown on the plans to intercept and filter sediment and decrease flow velocities from drainage areas of limited size. 4. Storm Drain Inlet Protection—3.07 A sediment filter shall be installed at all curb and drop inlets to storm drains that have become functional to prevent sediment from entering and accumulating in and being transferred by the culvert and associated drainage system prior to permanent stabilization of a disturbed project area. 5. Culvert Inlet Protection—3.08 A sediment filter shall be constructed on the upstream end of storm drain pipes to reduce sediment laden runoff from entering the pipe. 6. Temporary Diversion Dike—3.09 A temporary diversion dike shall be constructed where shown on the plans to channel storm water to a sediment trap. 3 7. Temporary Sediment Trap—3.13 A temporary sediment trap shall be constructed as shown on the grading plan for this project. It shall be constructed such that runoff from disturbed areas shall concentrate in the sediment trap before leaving the site. 8. Paved Flume—3.16 Permanent paved channels shall be constructed on slopes as shown on the plans. 9. Outlet Protection—3.18 The installation of riprap channel sections shall be installed at the downstream end of storm drain outlets to reduce erosion and under-cutting from scouring at outlets and to reduce flow velocities before storm water enters receiving channels below these outlets. 10. Rock Check Dams—3.20 Small temporary stone dams constructed across a swale or drainage ditch shall be constructed as shown on the plans. 11. Other practices shall be installed if required by Blackwell Engineering or the County E&SC Administrator. VEGETATIVE PRACTICES 1. Top soiling (stockpile)—3.30 Topsoil shall be stripped from areas to be graded and stockpiled for later use and shall be stabilized by silt fencing or seeding with seed mix appropriate for the time of year. 2. Temporary and Permanent Seeding—3.31 and 3.32 Temporary and permanent seeding appropriate to the time of year shall be installed according to Seeding and Mulching Table detail on the plan. MANAGEMENT STRATEGIES 1. Sediment trapping measures shall be installed prior to any excavation on site. 2. Construction shall be conducted so that disturbance of the existing ground cover will be minimized. 3. Construction shall be sequenced so that grading operations begin and end as quickly as possible. 4. Temporary seeding or other stabilization shall follow immediately after grading. 5. Areas that will be disturbed shall be clearly marked by flags, signs, etc. 4 6. The job superintendent shall be responsible for the installation and maintenance of all ``" erosion and sediment control practices. 7. After achieving adequate stabilization to the satisfaction of the E&SC Administrator, the temporary E&S controls shall be removed. PERMANENT STABILIZATION All areas disturbed by construction and not otherwise stabilized, shall be stabilized with permanent seeding within 7 days following finish grading. Seeding shall be done according to standard & specification 3.32, PERMANENT SEEDING, of the handbook Seeding shall be applied depending on time of the year according to E & S C handbook specifications. In all seeding operations, seed, fertilizer, and lime shall be applied prior to mulching. Erosion control blankets shall be installed over fill slopes which have been brought to final grade and have been seeded to protect the slopes from rill and gully erosion and to allow seed to germinate properly. Mulch(straw or fiber) shall be used on relatively flat areas. In all seeding operations, seed, fertilizer, and lime shall be applied prior to mulching. STORM WATER MANAGEMENT An underground detention piping system is proposed and shown on the plans. The outlet for the facility discharges into a constructed adequate channel "Ditch #2." The water quality requirements for Phase 1 is provided by two bio-retention basins. Long term `'"" " maintenance of the detention facility and outlet system shall be the responsibility of the property owner. This maintenance shall include periodic inspection, removing sediment buildup, cleaning of outlet pipe system of sedimentation and debris. Pre-construction runoff is: Q2 = 4.02 cfs, Q10= 5.18 cfs Post-construction runoff is: Q2 =2.61 cfs, Qi0 =3.14 cfs See Pre- and Post-construction runoff calculations and underground detention routing. MAINTENANCE In general, all erosion and sediment control measures shall be checked daily and after each significant rainfall. The following items shall be checked in particular: 1. The seeded area shall be checked regularly to ensure that a good stand is maintained. Areas shall be fertilized and reseeded as needed. 2. The gravel construction entrance shall be maintained in a condition, which will prevent tracking or flow of mud onto public right-of-ways. Periodic top dressing with additional stone or the washing and reworking of existing stone shall be required when the stone is covered or has been pushed into the soil. It shall be returned to its original depth of 6" (min.). 5 3. The silt fence shall be checked regularly for undermining or deterioration of the fabric. Sediment shall be removed when the level of sediment deposition reaches half way to the top of the barrier. 4. The outlet protection filter system shall be checked regularly for sediment buildup that will prevent drainage. If the stone filter is clogged by sediment, it shall be removed and cleaned or replaced. Riprap shall be inspected periodically to determine if high flows have caused scour beneath the riprap or filter fabric dislodged any of the stone. Care must be taken to properly control sediment-laden construction runoff, which may drain to the point of the new installation. 5. The inlet protection structure shall be inspected after each rain and repairs made as needed. Sediment shall be removed and the trap restored to its original dimensions when the sediment has accumulated to one half the design depth of the trap. 4. Maintenance of the Sediment Trap shall include mowing and repair of the detention basin berms, spillways, and grass areas; cleaning out sediment buildup; clearing of debris and trash from the outlet pipe system. As well as the removing of sediment when it reaches the cleanout level. 5. The temporary diversion dike shall be inspected after every storm and repairs made if necessary. Once every two weeks whether a storm has occurred or not, the measure shall be inspected and repairs made if needed. Damages made by construction traffic Now- or other activity must be repaired before the end of the working day. 6. The inlet and outlet protection filter system shall be checked regularly for sediment buildup which will prevent drainage. If the stone filter is clogged by sediment, it shall be removed and cleaned or replaced. 6 M '502w4 M O t LJL 1 O N U c c . u) a Jv) co o = ti Now. , p Wavy 2) o co - _ > LL. a) c cri a Za cnoo m a VUOo (? -S) <• Z oao0o - in O ~ N 00 00 (MO co O 0 0 0 0 CO J I-- O O O O O (n LL OOOO O 2 0 0o O o 0 0 0 0 w ,,- CO N J W N 0 0 0 O (n >>w In O O co I` H 0 N N N N DM) fy __ Ln Ln Ln Ln - W Q Z > a' in 000 O W W 00 O o O Ln —I a 6 , , c- (D W a NN NN CA 0 D000m m- woo +' N Cn CO OO O O O 'C ...., CT LL CO CD CO co (D > 5 06 , 46 d a) W O fir' ..W17'.) .0 O Q _I = O ((D ((O ((O. (�D .E) a' LL Z M (C (C (C 0 m I co 2 E �j W •E Q000 O J , o 0 0 0 Z Z xi Lri Lci Lci N 0 0) N IN N- CO 0 N 0 g 0000 0 - QQn 0 O• U W N N- O C O O — p z O O O O O G H• LL D U LL mZUWO U mmmm v mL O U 0000 o t` OW 0, o � U 0 Z ` to co O rn O x - w z W N oo 0 Ln N 4- N ,- N W 0 0 0 0 0 0 0 0 O w . 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MOM . — v EL 1.1h 15 . n5 111111MEI : (11 IlL:i 8 8 8 8 8 X 8 X 8 X di cd t,: .gi ..$ -.4, ,•-; e•J .. +6 OP)APIrdin 1' t co li) A-J 1-) 4.) q) H ,--f NISI. r-$ *-. •C: I—I I--I 9 1/17/2013 No"' Runoff Calculations - Rational Method Existing Flow From Site 1.) Area = 3.76 ac Project Name: New Hope Church Project# : 2167 2.) C = 0.21 0.25 ac @ 0.30 Grass 0.00 ac @ 0.90 Impervious 3.51 ac @ 0.20 Trees 3.) Time of Concentration a. Overland: (200'i L= 0 ft. Height= 0 ft. VDOT Drainage Manual Appendix 6D-1: T,= 0.0 min. b. Shallow: (1000' i L= 0 ft. Height= 0 ft. Average velocity= 0.0 fps (paved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. L= 0 ft. Height= 0 ft. Average velocity= 0.0 fps (unpaved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. T,= L/60V Subtotal T,= 0.0 min. c. Channel: L= ft. Height= 0 ft.(paved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. L= 0 ft. Height= 0 ft.(unpaved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. Subtotal T,= 0.0 min. d. Total Tc: Tc= 0.0 min. 4.) Rainfall Intensities: For Tc= 5 min. : 12 = 5.18 iph 125= 7.48 iph 110 = 6.67 iph 150 = 8.04 iph 1100= 8.76 iph 5.) Peak Flows: Q =ACI Q2 = 4.02 cfs Q25 = 5.81 cfs Q10= 5.18 cfs Q50= 6.25 cfs Q100= 6.81 cfs Blackwell Engineering 566 East Market Street Harrisonburg, VA 22801 2167 Detention Pond Sizing.xlsx 10 Runoff Calculations - Rational Method Proposed Flow From Site 1.) Area = 3.76 ac Project Name: New Hope Church Project# : 2167 2.) C = 0.47 2.58 ac @ 0.30 Grass 1.08 ac @ 0.90 Impervious 0.10 ac @ 0.20 Landscape Trees 3.) Time of Concentration a. Overland: (200' i L= 0 ft. Height= 0 ft. VDOT Drainage Manual Appendix 6D-1: T,= 0.0 min. b. Shallow: (1000'I L= 0 ft. Height= 0 ft. Average velocity= 0.0 fps (paved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. L= 0 ft. Height= 0 ft. Average velocity= 0.0 fps (unpaved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. T,= L/60V Subtotal T, = 0.0 min. c. Channel: L= ft. Height= 0 ft.(paved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. L= 0 ft. Height= 0 ft.(unpaved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. Subtotal T,= 0.0 min. d. Total Tc: Tc = 0.0 min. 4.) Rainfall Intensities: For Tc= 5 min. : 12 = 5.18 iph 125= 7.48 iph 110 = 6.67 iph 150 = 8.04 iph 1100= 8.76 iph 5.) Peak Flows: Q =ACI Q2 = 9.15 cfs Q25 = 13.20 cfs Q10= 11.77 cfs Q50= 14.20 cfs Q100= 15.47 cfs Blackwell Engineering 566 East Market Street Harrisonburg, VA 22801 2167 Detention Pond Sizing.xlsx 11 1/17/2013 DETENTION POND PRELIMINARY SIZING CALCULATIONS New Hope Church Equations used: Tc = sgrt[2 x C x A x a x (b-tc/4)/Qe]-b Vp = 0.5 x tc x 2.67 x (Qp-Qe+Qu)x 60 Vc = [QcxT+ {Qcxtc/4}-{QexT/2}-{3xQextc/4}] x60 Q = AxCxl Where: I = rainfall intensity for storm duration T. tc = time of concentrantion, minutes Tc = critical storm duration, minutes tc = watershed time of concentration, minutes Vp = peak storm storage volume required, cubic feet Vc = critical storm storage volume required, cubic feet Qe = existing peak flow for storm duration tc, cfs Qp = proposed peak flow for storm duration tc, cfs Qc = proposed critical flow for storm duration Tc, cfs Qa = allowable peak outflow, cfs 2 Year 10 Year a = 106.02 161.6 b = 15.51 18.73 Existing Conditions: A = 3.76 ac tc = 5.0 min C = 0.2066 Proposed Conditions: A = 3.76 ac tc = 5.0 min C = 0.4697 Design procedure: 1.) Existing rainfall intensities: 12 = 5.18 iph 110 = 6.67 iph 2.) Existing peak discharge Qe: Qe2 = 4.02 cfs Qe10 = 5.18 cfs 3.) Proposed peak rainfall intensities: 12 = 5.18 iph 110 = 6.67 iph 4.) Proposed peak discharge Qp (for tc): Qp2 = 9.15 cfs Qp10 = 11.77 cfs Blackwell Engineering '"+r" 566 East Market Street Harrisonburg, VA 22801 2167 Detention Pond Sizing.xlsx 12 1/17/2013 5.) Determine Volume for tc (peak storm volume): Vp2 = 2,049 cf Vp10 = 2,637 cf 6.) Uncontrolled Flow: Area = 0.40 ac (Entrance and drive) Qu2 = 0.97 cfs Qu10 = 1.25 cfs 7.) Offsite Flow: Area = 0 ac tc= 0 min C = 0 12= 0.0 Qi2 = 0.00 cfs 110= 0.0 Qi10 = 0.00 cfs 8.) Allowable Release Rate: Qa2 = 3.05 cfs Qa10 = 3.93 cfs Nor' Blackwell Engineering 'w•° 566 East Market Street Harrisonburg, VA 22801 2167 Detention Pond Sizing.xlsx 13 1/17/2013 2 YEAR CRITICAL DURATION STORM FOR RATIONAL METHOD USING a AND b COEFFICIENTS 2 YEAR CRITICAL DURATION STORM PROJECT NAME: New Hope Church ALBEMARLE COUNTY a= 106.02 A= 3.76 Acres b= 15.51 C= 0.47 t�= 0.00 minutes q.= 3.05 cfs Where Tc= critical storm duration in minutes C= Rational coefficient for developed area A= drainage area in acres(post development) to= Time of Concentration after development in minutes q., allowable peak outflow in cfs Tc= (2CAa(b-t./4)/go)1/2-b Tc= 28.12 minutes (critical duration) I = Rainfall Intensity(inches/hour) I = a/(b+Tc) I= 2.43 inches/hour for critical duration Critical Duration= 28.12 minutes Critical Duration Rainfall= 2.43 inches/hour Sow Peak inflow(Qo)= 4.29 cfs for Critical Duration V= ((QoTc)+(Qotc/4)-(goTc/2)-(3gotc/4))60 Approx.Basin Vol.= 4,666 cubic feet CRITICAL DURATION HYDROGRAPH 50 — 4.5 4.0 • 3.5 3.0 LL 2.5 -- 0 2.0 - 1.5 1.0 0.5 0.0• • 0 5 10 15 20 25 30 MINUTES '`w eo 2167 Detention Pond Sizing.xlsx 14 1/17/2013 10 YEAR CRITICAL DURATION STORM FOR RATIONAL METHOD �..o USING a AND b COEFFICIENTS 10 YEAR CRITICAL DURATION STORM PROJECT NAME: New Hope Church ALBEMARLE COUNTY a= 161.60 A= 3.76 Acres b= 18.73 C= 0.47 tc= 0.00 minutes qo= 3.93 cfs Where Tc= critical storm duration in minutes C = Rational coefficient for developed area A= drainage area in acres(post development) tc= Time of Concentration after development in minutes go= allowable peak outflow in cfs Tc= (2CAa(b-tc/4)/q jh/2-b Tc= 33.45 minutes (critical duration) I = Rainfall Intensity(inches/hour) I = a/(b+Tc) I= 3.10 inches/hour for critical duration Critical Duration= 33.45 minutes Critical Duration Rainfall= 3.10 inches/hour "` Peak inflow(Qo)= 5.47 cfs for Critical Duration V= ((QoTc)+(Qotc/4)-(goTc/2)-(3gotc/4))60 Approx. Basin Vol.= 7,036 cubic feet CRITICAL DURATION HYDROGRAPH 6.0 • • 5.0 4.0 y its 3.0 --- --- C 2.0 —- — - 1.0 0.0• 0 5 10 15 20 25 30 35 40 MINUTES 2167 Detention Pond Sizing.xlsx 15 1 Watershed Model Schematic Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk, Inc.v8 1-Existing Site Runoff 2-Proposed Site Runoff v 3-UG Detention Of Legend Hvd. Origin Description 1 Rational Existing Site Runoff Rational Proposed Site Runoff %`3 Reservoir UG Detention Project: 2167.gpw Tuesday, Jan 8, 2013 16 2 Hydrograph Return Period Recap y raflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk, Inc.v8 I4yd. Hydrograph Inflow Peak Outflow(cfs) Hydrograph moo. type hyd(s) Description (origin) 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr 1 Rational 4.090 ----- --- 5.263 Existing Site Runoff 2 Rational -- 9.153 11.78 ----- Proposed Site Runoff 3 Reservoir 2 2.607 3.142 ---- UG Detention Proj. file:2167.gpw Tuesday, Jan 8, 2013 17 3 Hydrograph Summary Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk, Inc.v8 I'+yd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph Now le°. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 4.090 1 5 1,227 -- ---- Existing Site Runoff 2 Rational 9.153 1 5 2,746 Proposed Site Runoff 3 Reservoir 2.607 1 9 2.744 2 523.77 1,835 UG Detention 2167.gpw Return Period: 2 Year Tuesday, Jan 8, 2013 18 4 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 Hyd. No. 1 Existing Site Runoff Hydrograph type = Rational Peak discharge = 4.090 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 1,227 cuft Drainage area = 3/60 ac Runoff coeff. = 0.21 Intensity = 5.180 in/hr Tc by User = 5.00 min IDF Curve = Albemarle.IDF Asc/Rec limb fact = 1/1 Existing Site Runoff Q (cfs) Hyd. No. 1 --2 Year Q (cfs) 5.00 -I- -- --- --i - ---- -- -- - - 5.00 4.00 - - - - -- --- — 4.00 3.00 - - - - - 3.00 2.00 — - - - 2.00 1.00 - _ 1.00 0.00 i 0.00 0 1 2 3 4 5 6 7 8 9 10 Hyd No. 1 Time(min) 19 5 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 ,,�, Hyd. No. 2 Proposed Site Runoff Hydrograph type = Rational Peak discharge = 9.153 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 2,746 cuft Drainage area = 3.760 ac Runoff coeff. = 0.47 Intensity = 5.180 in/hr Tc by User = 5.00 min IDF Curve = Albemarle.IDF Asc/Rec limb fact = 1/1 Proposed Site Runoff Q (cfs) Q cfs Hyd. No. 2--2 Year ( ) 10.00 10.00 8.00 8.00 6.00 6.00 / \ / \, 4.00 , - - - - - 4.00 2.00 , 2.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 -°� Hyd No. 2 Time(min) 20 6 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 ..,.. Hyd. No. 3 UG Detention Hydrograph type = Reservoir Peak discharge = 2.607 cfs Storm frequency = 2 yrs Time to peak = 9 min Time interval = 1 min Hyd. volume = 2,744 cuft Inflow hyd. No. = 2 - Proposed Site Runoff Max. Elevation = 523.77 ft Reservoir name = UG Detention 6-8 Max. Storage = 1,835 cuft Storage Indication method used. UG Detention Q (cfs) Q (cfs Hyd. No. 3--2 Year ) 10.00 10.00 ....® A 8.00 ' -- 8.00 6.00 -- - - 6.00 4.00 - -- 4.00 2.00 ... 2.00 i 0.00 _, - - 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 Time(min) ,-° Hyd No. 3 Hyd No. 2 i i 1 1 i i Total storage used = 1,835 cuft 21 Pond Report 7 Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Aufodesk,Inc.v8 Tuesday,Jan 8,2013 Pond No. 1 - UG Detention 6-8 Pond Data UG Chambers-Invert elev.=521.00 ft , Rise x Span=4.00 x 4.00 ft , Barrel Len=200.00 ft, No.Barrels=1 , Slope=0.00%, Headers=No Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 521.00 n/a 0 0 0.40 521.40 n/a 131 131 0.80 521.80 n/a 227 358 1.20 522.20 n/a 276 635 1.60 522.60 n/a 304 939 2.00 523.00 n/a 318 1,257 2.40 523.40 n/a 318 1,575 2.80 523.80 n/a 304 1,880 3.20 524.20 n/a 276 2,156 3.60 524.60 n/a 227 2,383 4.00 525.00 n/a 131 2,514 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 8.00 0.00 0.00 0.00 Crest Len(ft) = 0.00 0.00 0.00 0.00 Span(in) = 8.00 0.00 0.00 0.00 Crest El.(ft) = 0.00 0.00 0.00 0.00 No.Barrels = 1 0 0 0 Weir Coeff. = 3.33 3.33 3.33 3.33 Invert El.(ft) = 521.00 0.00 0.00 0.00 Weir Type = -- - --- Length(ft) = 20.00 0.00 0.00 0.00 Multi-Stage = No No No No Slope(%) = 1.00 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000 (by Contour) Multi-Stage = n/a No No No TW Elev.(ft) = 0.00 Note Culvert/Orifice outflows are analyzed under inlet(ic)and outlet(oc)control.Weir risers checked for onfice conditions(ic)and submergence(s). Stage/Storage/Discharge Table Stage Storage Elevation Clv A Clv B Clv C PrfRsr Wr A Wr B Wr C Wr D Exfil User Total ft cuft ft cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs cfs 0.00 0 521.00 0.00 --- --- --- --- --- --- --- --- --- 0.000 0.40 131 521.40 0.47 is --- --- --- --- --- --- --- --- -- 0.471 0.80 358 521.80 1.01 oc --- --- --- --- --- --- --- --- --- 1.010 1.20 635 522.20 1.50 oc -- --- --- --- --- --- --- --- --- 1.498 1.60 939 522.60 1.86 oc --- --- --- --- --- -- --- --- --- 1.863 2.00 1,257 523.00 2.17 oc --- --- --- --- --- --- --- --- --- 2.167 2.40 1,575 523.40 2.42 is --- --- -- - --- --- --- --- --- 2.416 2.80 1,880 523.80 2.64 is -- --- --- --- - --- --- --- --- 2.639 3.20 2,156 524.20 2.85 ic -- --- --- --- --- --- --- --- --- 2.845 3.60 2,383 524.60 3.04 is -- --- -- --- --- --- --- --- --- 3.037 4.00 2,514 525.00 3.22 is --- - --- --- --- --- --- --- --- 3.218 22 8 Hydrograph Summary Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk, Inc.v8 I 'yd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph ,wo. type flow interval Peak volume hyd(s) elevation strge used Description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 5.263 1 5 1,579 --- Existing Site Runoff 2 Rational 11.78 1 5 3.534 ----- Proposed Site Runoff 3 Reservoir 3.142 1 9 3.532 2 524.90 2,458 UG Detention 2167.gpw Return Period: 10 Year Tuesday, Jan 8, 2013 23 9 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 Hyd. No. 1 Existing Site Runoff Hydrograph type = Rational Peak discharge = 5.263 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 1,579 cuft Drainage area = 3.760 ac Runoff coeff. = 0.21 Intensity = 6.666 in/hr Tc by User = 5.00 min IDF Curve = Albemarle.IDF Asc/Rec limb fact = 1/1 Q (cfs) Existing Site Runoff Hyd. No. 1 -- 10 Year Q (cfs) 6.00 -- - -- - - - 6.00 'Iwo, 5.00 ---- --- -- - --- — -- - --- - - - --- — 5.00 4.00 4.00 3.00 A -- - 3.00 2.00 4 2.00 1.00 — - - - 1.00 0.00 ----- - - -[ — -- — - - -- - -- 0.00 0 1 2 3 4 5 6 7 8 9 10 ,,. Hyd No. 1 Time(min) 24 Hydrograph Report 10 Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 �- Hyd. No. 2 Proposed Site Runoff Hydrograph type = Rational Peak discharge = 11.78 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 3,534 cuft Drainage area = 3.760 ac Runoff coeff. = 0.47 Intensity = 6.666 in/hr Tc by User = 5.00 min IDF Curve = Albemarle.IDF Asc/Rec limb fact = 1/1 Proposed Site Runoff Q (cfs) Hyd. No. 2-- 10 Year Q (cfs) 12.00 - -- - 12.00 .10.00 10.00 8.00 ‘ 8.00 / \ / 6.00 N. 6.00 4.00 - -- - - 4.00 2.00 2.00 0.00 0.00 0 1 2 3 4 5 6 7 8 9 10 s..,. a Hyd No. 2 Time(min) 25 11 Hydrograph Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 Hyd. No. 3 UG Detention Hydrograph type = Reservoir Peak discharge = 3.142 cfs Storm frequency = 10 yrs Time to peak = 9 min Time interval = 1 min Hyd. volume = 3,532 cuft Inflow hyd. No. = 2 - Proposed Site Runoff Max. Elevation = 524.90 ft Reservoir name = UG Detention 6-8 Max. Storage = 2,458 cuft Storage Indication method used. UG Detention Q (cfs) Q (cfs Hyd. No. 3-- 10 Year ) 12.00 12.00 -- -- --- -- r'1000 10.00 8.00 8.00 6.00 l +, 6.00 i I 4.00 4.00 I I I 2.00 2.00 0.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 �re Hyd No. 3 Hyd No. 2 1 I ! I I Total storage used = 2,458 cuft Time(min) 26 12 Hydraflow Rainfall Report Hydraflow Hydrographs Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc.v8 Tuesday,Jan 8,2013 *ay, Return Intensity-Duration-Frequency Equation Coefficients(FHA) Period (Yrs) B D E (N/A) 1 0.0000 0.0000 0.0000 2 49.0200 10.5000 0.8200 3 0.0000 0.0000 0.0000 5 55.7100 11.5000 0.8000 10 46.9500 9.5000 0.7300 25 40.1100 7.7500 0.6600 50 35.6800 6.5000 0.6100 100 31.0900 5.0000 0.5500 File name:Albemarle.IDF Intensity=B/(Tc+ D)AE Return Intensity Values(in/hr) Period (Yrs) 5 min 10 15 20 25 30 35 40 45 50 55 60 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2 5.18 4.12 3.44 2.97 2.63 2.36 2.14 1.97 1.82 1.70 1.59 1.50 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 5.91 4.79 4.05 3.53 3.13 2.83 2.58 2.38 2.21 2.06 1.94 1.83 10 6.67 5.37 4.55 3.97 3.54 3.21 2.94 2.72 2.54 2.38 2.24 2.12 25 7.48 6.01 5.10 4.47 4.01 3.65 3.36 3.13 2.93 2.76 2.61 2.48 50 8.04 6.45 5.49 4.83 4.35 3.98 3.68 3.43 3.22 3.05 2.89 2.76 100 8.76 7.01 5.98 5.29 4.79 4.40 4.09 3.83 3.62 3.43 3.27 3.13 Tc=time in minutes.Values may exceed 60. Precip.file name:Rockinqham.pcp Rainfall Precipitation Table(in) Storm Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 3.00 2.60 0.00 3.30 3.90 4.70 5.40 6.10 SCS 6-Hr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-1st 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-2nd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-3rd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-41h 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-Indy 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Custom 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 27 File:2167 Tc Albemade.xlsx Printed:1/15/2013 xtorrir Runoff Calculations - Rational Method Drainage Area #1 to Existing Culvert in Route 606 1.) Area= 1.89 ac Project Name: New Hope Community Church Project# : 2167 2.) C = 0.48 0.95 ac @ 0.30 Grass 0.62 ac @ 0.90 Phase 1 and 2 Impervious 0.32 ac @ 0.20 Trees 3.) Time of Concentration Slope a. Overland: (200'max) L = ft. Height= ft. VDOT Drainage Manual Appendix 6D-1: T,= 0.0 min. b. Shallow: (1000' max) L = ft. Height= ft. Average velocity= 0.0 fps (paved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. L= ft. Height= ft. Average velocity= 0.0 fps (unpaved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. T,= L/60V Subtotal T,= 0.0 min. c. Channel: L= ft. Height= ft.(paved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. L= ft. Height= ft.(unpaved; VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. Subtotal T, = 0.0 min. d. Total Tc: T,= 0.0 min. 4.) Rainfall Intensities: For T,= 5 min. 12 = 5.18 iph 125 = 7.48 iph 110 = 6.67 iph 1100= 8.76 iph 5.) Proposed Flows: Q =ACI 02 = 4.70 cfs 025 = 6.78 cfs 010= 6.05 cfs 0100 = 7.95 cfs 28 File:2167 Tc Albemarle.xlsx Printed:1/15/2013 Now Runoff Calculations - Rational Method Drainage Area #2 to Proposed Entrance Culvert 2-1 1.) Area= 1.57 ac Project Name: New Hope Community Church Project#: 2167 2.) C = 0.43 0.85 ac @ 0.30 Grass 0.40 ac @ 0.90 Phase 1 and 2 Impervious 0.32 ac @ 0.20 Trees 3.) Time of Concentration Slope a. Overland: (200' max) L = ft. Height= ft. VDOT Drainage Manual Appendix 6D-1: T,= 0.0 min. b. Shallow: (1000'max) L = ft. Height= ft. Average velocity= 0.0 fps (paved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. L= ft. Height= ft. Average velocity= 0.0 fps (unpaved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. ,,,. T,= L/60V Subtotal T,= 0.0 min. c. Channel: L= ft. Height= ft.(paved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. L= ft. Height= ft.(unpaved; VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. Subtotal T,= 0.0 min. d. Total Tc: T,= 0.0 min. 4.) Rainfall Intensities: For T,= 5 min. 12 = 5.18 iph 125 = 7.48 iph 110 = 6.67 iph 1100= 8.76 iph 5.) Proposed Flows: Q =ACI 02 = 3.52 cfs 025 = 5.08 cfs Q10= 4.53 cfs 0100 = 5.95 cfs 29 File:2167 Tc Albemarle.xlsx Printed:1/15/2013 Nifty Runoff Calculations - Rational Method Drainage Sub-Area #2.1 - Existing Ditch from Phase 2 Parking Lot 1.) Area= 0.30 ac Project Name: New Hope Community Church Project# : 2167 2.) C = 0.64 0.13 ac @ 0.30 Grass 0.17 ac @ 0.90 Phase 2 Impervious 0.00 ac @ 0.00 Other 3.) Time of Concentration Slope a. Overland: (200' max) L = ft. Height= ft. VDOT Drainage Manual Appendix 6D-1: T,= 0.0 min. b. Shallow: (1000'max) L = ft. Height= ft. Average velocity= 0.0 fps (paved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. L= ft. Height= ft. Average velocity= 0.0 fps (unpaved) VDOT Drainage Manual Appendix 6D-6: T,= 0.0 min. T,= L/60V Subtotal T,= 0.0 min. c. Channel: L= ft. Height= ft.(paved) VDOT Drainage Manual Appendix 6D-5: T,= 0.0 min. L= ft. Height= ft.(unpaved; VDOT Drainage Manual Appendix 6D-5: T, = 0.0 min. Subtotal T,= 0.0 min. d. Total Tc: T,= 0.0 min. 4.) Rainfall Intensities: For T,= 5 min. 12 = 5.18 iph 125= 7.48 iph 110= 6.67 iph 1100 = 8.76 iph 5.) Proposed Flows: Q =ACI Q2 = 0.99 cfs 025= 1.44 cfs Q10= 1.28 cfs 0100= 1.68 cfs 30 Ale: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Ditch#1 -From Bioretention Basin#1 (Minimum Slope) Tc=5min A=0.16 ac C =0.90 12= 5.18 in/hr 110 =6.67 in/hr Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 0.75 cfs 0.96 cfs Slope S = 6.80 % Lining Type = 2 Kentucky bluegrass Permissible V= 4 fps (Table 5-14) Channel Type = 1 V ditch Left side slope = 3 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.43 ft 0.55 ft Area A= 0.55 sf 0.91 sf Hydraulic radius R= 0.20 ft 0.26 ft VxR= 0.82 1.04 Manning's n = 0.093 Class C 0.149 Class B (Plate 5-29) Manning's Equation = 0.80 cfs 1.07 fps Manning's Equation = 1.44 fps 0.97 cfs (OK. Less than permissible 4 fps) (OK. Greater than actual 0.96 cfs) Source: Virginia Erosion and Sediment Control Handbook, Chapter 5. 31 File: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Ditch#1 -From Bioretention Basin#1 (Maximum Slope) Tc= 5min A=0.16ac C =0.90 12=5.18in/hr Ito=6.67in/hr Sow Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 0.75 cfs 0.96 cfs Slope S = 12.00 % Lining Type = 2 Kentucky bluegrass Permissible V= 3 fps (Table 5-14) Channel Type = 1 V ditch Left side slope = 3 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.42 ft 0.54 ft Area A= 0.53 sf 0.87 sf Hydraulic radius R= 0.20 ft 0.26 ft VxR = 0.60 0.77 Manning's n = 0.115 Class C 0.184 Class B (Plate 5-29) Manning's Equation = 0.81 cfs 1.13 fps Manning's Equation = 1.53 fps 0.99 cfs (OK. Less than permissible 3 fps) (OK. Greater than actual 0.96 cfs) Source: Virginia Erosion and Sediment Control Handbook, Chapter 5. 32 File: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Ditch#1 -At Upstream End of Entrance Culvert 2-1 T,= 5min A=1.57 ac C =0.43 12= 5.18 in/hr 110=6.67 in/hr Now Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 3.52 cfs 4.53 cfs Slope S = 6.10 % Lining Type = 2 Kentucky bluegrass Permissible V= 4 fps (Table 5-14) Channel Type = 1 V ditch Left side slope = 3 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.69 ft 0.89 ft Area A= 1.43 sf 2.38 sf Hydraulic radius R= 0.33 ft 0.42 ft V x R= 1.31 1.69 Manning's n = 0.070 Class C 0.108 Class B (Plate 5-29) Manning's Equation = 3.56 cfs 1.91 fps New Manning's Equation = 2.49 fps 4.54]cfs (OK. Less than permissible 4 fps) (OK. Greater than actual 4.53 cfs) Source:Virginia Erosion and Sediment Control Handbook, Chapter 5. 33 File: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Ditch#2 -From UG Detention (Minimum Slope) (Discharges from Underground Detention Routing) Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 2.61 cfs 3.14 cfs Slope S = 4.40 % Lining Type = 2 Kentucky bluegrass Permissible V= 5 fps (Table 5-14) Channel Type = 1 V ditch Left side slope = 3 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.64 ft 0.81 ft Area A= 1.23 sf 1.97 sf Hydraulic radius R= 0.30 ft 0.38 ft VxR= 1.52 1.92 Manning's n = 0.065 Class C 0.100 Class B (Plate 5-29) Manning's Equation = 2.69 cfs 1.66 fps '""' Manning's Equation = 2.19 fps 3.27 cfs (OK. Less than permissible 5 fps) (OK. Greater than actual 3.14 cfs) Source:Virginia Erosion and Sediment Control Handbook, Chapter 5. 34 File: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Ditch#2 -From UG Detention (Average Slope) (Discharges from Underground Detention Routing) v... Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 2.61 cfs 3.14 cfs Slope S = 10.50 % Lining Type = 2 Kentucky bluegrass Permissible V= 3 fps (Table 5-14) Channel Type = 1 V ditch Left side slope= 3 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.61 ft 0.78 ft Area A= 1.12 sf 1.83 sf Hydraulic radius R = 0.29 ft 0.37 ft V x R= 0.87 1.11 Manning's n = 0.090 Class C 0.143 Class B (Plate 5-29) Manning's Equation = 2.63 cfs 1.74 fps slaw- Manning's Equation = 2.36 fps 3.18 cfs (OK. Less than permissible 3 fps) (OK. Greater than actual 3.14 cfs) Source:Virginia Erosion and Sediment Control Handbook, Chapter 5. 35 File: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Ditch#2-From UG Detention (Maximum Slope) (Discharges from Underground Detention Routing) Now. Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 2.61 cfs 3.14 cfs SlopeS = 13.10 % Lining Type= 2 Kentucky bluegrass Permissible V= 3 fps (Table 5-14) Channel Type = 1 V ditch Left side slope = 3 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.59 ft 0.75 ft Area A= 1.04 sf 1.69 sf Hydraulic radius R= 0.28 ft 0.36 ft VxR = 0.84 1.07 Manning's n = 0.092 Class C 0.146 Class B (Plate 5-29) Manning's Equation = 2.63 cfs 1.85 fps N""" Manning's Equation = 2.52 fps 3.14 cfs (OK. Less than permissible 3 fps) (OK. Greater than actual 3.14 cfs) Source: Virginia Erosion and Sediment Control Handbook, Chapter 5. Nsettsr 36 File: 2167 Ditch.xlsx OPEN CHANNEL FLOW CALCULATIONS Printed: 1/15/2013 Existing Ditch#3 -Drainage from Phase 2 Parking Lot T,= 5min A=0.30 ac C =0.64 12= 5.18 in/hr I,o=6.67in/hr Project Name: New Hope Church Project# : 2167 2 Year 10 Year Discharge Q = 0.99 cfs 1.28 cfs Slope S = 10.00 % Lining Type = 2 Kentucky bluegrass Permissible V= 4 fps (Table 5-14) Channel Type= 1 V ditch Left side slope = 2 : 1 Right side slope = 3 : 1 2 Year 10 Year Depth d = 0.47 ft 0.61 ft Area A= 0.55 sf 0.93 sf Hydraulic radius R= 0.22 ft 0.28 ft V x R= 0.87 1.13 Manning's n = 0.089 Class C 0.141 Class B (Plate 5-29) Manning's Equation = 1.05 cfs 1.44 fps Manning's Equation = 1.90 fps 1.34 cfs (OK. Less than permissible 4 fps) (OK. Greater than actual 1.28 cfs) Source: Virginia Erosion and Sediment Control Handbook, Chapter 5. 37 Culvert Report Hydraflow Express Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc. Monday,Jan 14 2013 ''r' Existing 15-inch RCP Culvert in Route 606 at DA #1 Invert Elev Dn (ft) = 490.93 Calculations Pipe Length (ft) = 52.66 Qmin (cfs) = 6.05 Slope (%) = 1.41 Qmax (cfs) = 6.05 Invert Elev Up (ft) = 491.67 Rise (in) = 15.0 Tailwater Elev (ft) = (dc+D)/2 Shape = Cir Highlighted Span (in) = 15.0 Qtotal (cfs) = 6.05 No. Barrels = 1 Qpipe (cfs) = 6.05 n-Value = 0.013 Qovertop (cfs) = 0.00 Inlet Edge = 0 Veloc Dn (ft/s) = 5.20 Coeff. K,M,c,Y,k = 0.0045, 2, 0.0317, 0.69, 0.5 Veloc Up (ft/s) = 5.76 Embankment HGL Dn (ft) = 492.05 HGL Up (ft) = 492.67 Top Elevation (ft) = 495.32 Hw Elev (ft) = 493.29 Top Width (ft) = 20.00 Hw/D (ft) = 1.30 Crest Width (ft) = 10.00 Flow Regime = Inlet Control Eli",'A Existing 15-inch RCP Culvert in Route 606 at DA#1 liw Depth titt 49r5 23 4.33 435:I3 - fir} ` � i, 3 33 ,,' : ' 433.-r r` u . _ e ,, ta 4:2.2c3 :'.33 431.33 -,._ 7 430.3x5 -L.7 43:. !:' ^ -2. •7 3 13 15 23 25 5 . 5:J 55 55 7J 75 .'r advert HGL --.- - Ernban- Reach h i `fir 38 Culvert Report Hydraflow Express Extension for AutoCAD®Civil 3D®2011 by Autodesk,Inc. Monday,Jan 14 2013 `" Entrance Culvert 1 - 2 Invert Elev Dn (ft) = 494.40 Calculations Pipe Length (ft) = 65.30 Qmin (cfs) = 4.53 Slope (%) = 3.22 Qmax (cfs) = 4.53 Invert Elev Up (ft) = 496.50 Tailwater Elev (ft) = (dc+D)/2 Rise (in) = 15.0 Shape = Cir Highlighted Span (in) = 15.0 Qtotal (cfs) = 4.53 No. Barrels = 1 Qpipe (cfs) = 4.53 n-Value = 0.012 Qovertop (cfs) = 0.00 Inlet Edge = 0 Veloc Dn (ft/s) = 4.09 Coeff. K,M,c,Y,k = 0.0045, 2, 0.0317, 0.69, 0.5 Veloc Up (ft/s) = 5.00 HGL Dn (ft) = 495.46 Embankment HGL Up (ft) = 497.37 Top Elevation (ft) = 498.00 Hw Elev (ft) = 497.81 Top Width (ft) = 10.00 Hw/D (ft) = 1.05 Crest Width (ft) = 10.00 Flow Regime = Inlet Control Niwar Elev ink Entrance Culvert 1 -2 Her Depth Int 499.30 2.53 498.30 ,.SD Inlet contr:d 497.:'D 0 50 438.aD -3.53 495.33 gIIIIIIIIII -1.53 494)0 _2.53 493..E -3.53 3 5 10 15 20 25 33 35 43 45 53 55 53 55 70 75 83 85 80 sir Cutrert HOL Embank Reach kilt 39 -.J EE — V) V) V) V) 7) Lti Z a *) H. 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IKEt.),+ tr> "" -` 14--z...==a.-.,...=.7 w" t7.=!..".===4 ------.. =-- g g eh .. ............_. .......g...... a aiNiaraalmmilVIN '•• ••=El: • • .'=••• =En Ima S..■ I...1•1. % 0 === i0-..-.===.: mis ,..,. .4 •It =cm- 41.=,mono=mom LI.I CI !NV MEM!MMMM MM.=I= I= IP la.= 4 ,.....! ■7...741.-..S-5.1:.-1.....r.'' = -7- :—_ •- ... 11 ---, ------—...—.= CI. •■•====211EXCESII CC 6D' - ''''''"---"."".•"•-• I 1MaNallahaw.mama.as. t ■a ma.m==:::V.••' .7• 11 =2=Mignan I -71 1 --trams p-, I- Ci 1 g 74 m a ■ r 1 0 1-1 0 ..r 0 il-0•••• II 0 . 03 X ima c 5 i as -4 ...J. ...• 11 CI 2 44 0.ea Cx Ct.Gi Ellop., tl) E-_- 0 w c I, a) 3 ir-0 40 File: 2167 Bio Retention.xls Printed: 1/15/2013 ,,,r„ BIO-RETENTION BASIN SIZING BIO-RETENTION BASIN#1 (Virginia SWM Handbook Figure 3.11-2) Design Criteria: Drainage area = 0.16 ac Imperv. Area = 0.13 ac % Impervious = 85% Bio Basin Area = 5.0% Plants per 1000 sf = 10 (based on basin size) Shrub to Tree ratio = 3 Calculations: Basin Size: Required Size= 287 sf Actual Width (W) = 15.0 Actual Length (L) = 20.0 Actual Size= 300 sf Plants: Number of Plants = 3 Number of Shrubs= 2 Number of Trees= 1 BIO-RETENTION BASIN#2 (Virginia SWM Hanbook Figure 3.11-4) Design Criteria: Drainage area = 0.69 ac Imperv. Area = 0.65 ac % Impervious = 94% `"r' Bio Basin Area = 5.0% Plants per 1000 sf= 10 (based on basin size) Shrub to Tree ratio = 3 Calculations: Basin Size: Required Size = 1411 sf Actual Width (W) = 30.0 Actual Length (L) = 47.0 Actual Size = 1410 sf Plants: Number of Plants = 14 Number of Shrubs= 11 Number of Trees = 4 41 File: 2167 Sediment Trap.xls Printed: 1/15/2013 "ow, NEW HOPE CHURCH SEDIMENT TRAP CALCULATIONS SEDIMENT TRAP ST-1 Requirements: Drainage area = 0.61 ac. Wet storage = 67 cy per acre = 1,103 cf Dry storage = 67 cy per acre = 1,103 cf Calculated Size: Wet Dry Width (W) = 10 24 Length (L) = 40 54 Depth (D) = 3.5 1.5 Area (A) = 400 1,296 Wet Volume = 0.85xWxLxD = 1,190 cf Dry Volume = D(A(w)+A(d))/2 = 1,272 cf Length of Stone Filter: D.A.x 6' = 4 ft. 42 woo•6uuaeui6u3poM>loo19039 :HoW-3 N 0w 409L—b£4(04S) XV3 SSS6—Z£4(04S) 3NOHd 1 1.6ZZ do '3111AS3110121YH0 N 3'Td 108Za n a H I--- oiw6�i 6�n uosu�o Z aa� a �� so 00£ 3lIfS '1117211 310YNIW3S 91717E Z N U lS l W 3 999 Q, H� fH� 3dOH M3N Q `DNII2 HHNIDNH o 0 o r llI3 V I dV V32V 3O VNIVda _`4r 1 k �' \ o . \it, ) 0 v) \ \i67°mob V O - �i w J Q U t tkr ' _ - Ili O i O j �It t`J \ , , IA‘,„+11+ 5 +t $\1\ ,' \ ■ It\I\ ' P.- + I” \ \ \ \1 11 • 11 * y{ ii • I ' N. „r%/ ' ( r t I rl 4„,, , k R 1 1 + i 1 f ' - , \ Niii\,114 1 \ W '''''' •," '). 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