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HomeMy WebLinkAboutSDP200900036 Calculations Erosion Control Plan 2009-05-01ALBEMARLE COUNTY PUBLIC SCHOOLS MONTICELLO HIGH SCHOOL STADIUM TURF REPLACEMENT MINOR SITE PLAN AMENDMENT AND EROSION AND SEDIMENT CONTROL PLAN STORMWATER MANAGEMENT ANALYSIS Prepared For: Albemarle County Public Schools Charlottesville, Virginia Prepared By: DEWBERRY & DAVIS, INC. 4180 Innslake Drive Glen Allen, Virginia 23060 May 1, 2009 Revised May 22, 2009) 101 Dewberry® TABLE OF CONTENTS SECTION TAB PROJECT NARRATIVE 1 PROPOSED DESIGN INFORMATION & CALCULATIONS 2 PROPOSED STORMWATER MANGEMENT ROUTING 3 ADEQUATE OUTFALL ANALYSIS 4 SUPPORTING ILLUSTRATIONS 5 EXISTING SOILS INFORMATION 6 EXISTING SITE ANALYSIS 7 pR AllSt8 Albemarle County Public Schools Monticello High School Stadium Turf Replacement Minor Site Plan Amendment and Erosion and Sediment Control Plan Stormwater Management Analysis Background Albemarle County Public Schools and Monticello High School (Client) contracted with Dewberry & Davis, Inc. (Dewberry) to complete design plans for converting Monticello High School Football Stadium to a synthetic turf field. The field is located on the grounds of Monticello High School off of Mills Creek Drive in Charlottesville, Virginia. The proposed turf field site area will be bound by the existing goal posts for the football field to the north and south and the existing track to the east and west. The "D" zone areas, or areas beyond the field goal posts to the edge of the track, will remain grass. The field is currently owned and maintained by Albemarle County Public Schools. Figure 1 in Tab 5 under Supporting Illustrations is a Vicinity Map that shows the location of the project site. The Client anticipates utilizing General Sports Venue /AstroTurfUSA (GSV) as the contractor to construct and complete this project. Existing Conditions Analysis Dewberry obtained as -built information from the Client (October 1996) and completed a site survey April 2009) to gain an understanding of the existing drainage and stormwater management at the project site. Given the requirement to provide stormwater runoff controls, Dewberry worked with the installer to incorporate an innovative modification to the turf system that will allow for non- impeded natural infiltration of the stormwater into the soil at the fields without having to modify the existing stormwater management facility. Design Requirements Based on discussions with the County of Albemarle Department of Community Development CADCD), it is our understanding that Dewberry will be required to show how the new synthetic turf field provides both water quantity and an element of water quality control. Proposed Turf Field and Under -drain System The proposed turf system will consist of 2.5- inches of synthetic turf over 2- inches of #8 stone and fl- inches of #57 stone over a pervious geotextile liner (Mirafi 140N) on an existing excavated soil surface that allows for infiltration and ground water recharge over the approxirnate 205.5' by 368.5' field area (75,697 sf). A typical synthetic turf profile from the installer is part of this report as Figure 2 in Tab 5. The manufacturer's data states that the synthetic turf with stone base system has an infiltration rate of greater than 20 inches of rain per hour. This will allow for unrestrained infiltration into the existing soils below. The void area in the stone per Luck Stone calculation is approximately 43.0% for the #8 stone and 42.2% for the #57 stone. The void area between the stones will provide the storage area for the storm events to infiltrate into the underlying existing soils. An under -drain system will be provided that can carry off the excess flow not recharged back into the water table. The design calls for a 10" perforated collector pipe to run around the perimeter of the field on all sides at a 0.5% slope. The field will drain to these perforated collector pipes which will then tie into the two existing storm drain inlets located on the sidelines at midfield. Figure 3 in Tab 5 shows the layout of this system. Typical excavation for the collector pipes would be a 2 -foot wide by 3 -foot deep trench below the typical sub - drainage system section for the 10" collector pipe. The invert out of the collector pipe, where it ties in to the existing service, will be 6" above the bottom of the 3 -foot deep trench. The pipe will then run at a 0.5% slope around the perimeter of the field to its highest point located at the existing field goal posts. The bottom of the trench located adjacent to the sidelines will be one consistent elevation at 485.09. The trench will then slope up at a 1.5% slope once it turns 90 degrees and runs towards the field goal posts. This will put the invert of the collector pipe approximately 17" and 6" above the bottom of the trench at the corners of the field and at the field goal posts respectively. The existing field is crowned at approximately 2.2% from the center of the field to the sidelines and slopes up slightly towards the south end zone. There is also an existing ditch that runs parallel with the sidelines that channels drainage into the 6 inlets around the field. These plans call for reducing this slope to a consistent 1.5% crown towards the sidelines to a new ditch located 12.6' off of the existing edge of track. From here the field will slope up at 1.5% until it ties into the existing grade at the edge of the track. This grading activity is only for those areas within the specified limits of the turf area. This will provide a more level playing surface while still providing the necessary drainage needed. The proposed graded ditch will not collect water due to the field absorption rate of 20- inches of rain per hour. This re- grading of the field will generate soil that needs to be removed from the site. The contractor will be responsible for the disposal of all excavated soil at an approved off - site location. It is the contractor's responsibility to obtain and present all necessary documentation for this location to local and state agencies. The design plans will not identify this location. Addressing On -site Stormwater Management Requirement Summary both Quantity and Quality) Water Quantity is detailed below, in that when the soils can not infiltrate fast enough, an under -drain collector system has been installed to carry the excess runoff to the existing storm outfall and stormwater management facility. In Tab 3 of this report the proposed routing shows that the post- development flows are controlled within the stone and under -drain system to release below the pre- development flow conditions, in the event that the soils cannot infiltrate the storm runoff fast enough. Water Quality is also addressed below, in that the proposed turf system does not prevent or impede natural infiltration into the soils through use of a pervious (porous) liner. Detailed Proposed Water Quantity Control Within the typical field section and collector pipe layout described above, Dewberry calculated how this system provides water quantity control through the aggregate, stone layers, and under drain system. In the event that the soils cannot infiltrate the storm runoff fast enough. These layers will provide approximately 5,152 cf or 0.1183 acre -feet of storage through voids around the stone media, and the collector pipes will discharge below the current runoff rate of the existing field. This is shown in the stormwater management routing under Tab 3 of this report. The voids in the stone base act as a storage area which allows the drainage to infiltrate back into the existing ground. Excess runoff is released in the collector pipe system which acts as the control structure. This will ultimately control the post developed turf conditions to below the pre - developed grass condition runoff rates. These facts should satisfy CADCD that the new synthetic turf field meets or exceeds the stormwater quantity controls associated with the existing grass fields. A detailed stormwater management routing that simulates these conditions is provided in Tab 3 of this report. This study estimated the time of concentration for both pre- and post- development to be 10 minutes across the proposed site development area. The pre - development "C" value is estimated to be 0.55 and 0.80 for the post developed condition. The 10 -inch collector pipes serve as the controlled release structures and the pond storage is the void in the stone. This routing produced the following results. Pre Developed Post Developed Controlled Release Water cfs)cfs)cfs) Surface Elevation 2 Year 7.07 7.10 6.67 487.62 10 Year 9.21 9.32 7.81 488.22 100 Year 12.02 12.07 8.63 488.71 Detailed Proposed Water Quality Control The water quality for the project is addressed within the workings of the various components of the new synthetic turf system. The turf and stone itself allows for the storm runoff to infiltrate at a rate greater than 20- inches per hour. The voids in the stone will provide temporary storage for the drainage before it infiltrates back into the soils beneath the stone through the geotextile liner. The new turf system will operate as a natural grass surface does today allowing for the ground water to be recharged. The new turf system will allow for infiltration back into the surrounding soils. The existing soils information and geotechnical information for the project site is included in this report in Tab 6. This information shows that clayey silt is located 1.0 to 5.0 -feet below the surface, according to the boring log documents. If the entire field were to be considered impervious in its proposed condition, half an inch of rain over the field would generate a water quality volume of 3,155 cubic feet. The trench that runs around the perimeter of the field will supply approximately 340 cf of storage space beneath the invert out of the 10" collector pipe. In addition, the entire field has an average infiltration rate of at least 0.1" per hour or 630 cubic feet per hour according to the geotechnical study conducted for this project under Tab 6. This will allow the entire water quality volume to infiltrate in to the existing soils in approximately 5 hours, plus an additional 340 cf of storage will be provided beneath the collector pipes. These calculations can be found under Tab 2 of this report. The following information provided from Albemarle County Public Schools, shows the amount of fertilizer used per year at Monticello High School Football Stadium and documents the anticipated reduction by converting the field to synthetic turf. Over the past 12 months a total of 6.5 lbs of Nitrogen, 2.5 lbs of Phosphorus, and 3.0 lbs of Potash have been applied to the football field per 1,000 sf. A total of 75,697 sf of field will be converted to synthetic turf which will reduce the amount of fertilizer needed in that area. This equates to a reduction of approximately 492 lbs of Nitrogen, 189 lbs of Phosphorus, and 227 lbs of Potash. A meeting was held on May 18 2009 at the county office to discuss how water quality would be addressed on site. It was decided that a flow meter would be installed at the outlet pipe after construction is complete. The results from the flow meter will be evaluated and a report will be prepared that compares the theoretical pre - existing conditions to the proposed conditions in order to show how water quality is being addressed by means of reduced outflow. It was agreed that the results from the flow meter tests would not warrant additional future measures to be constructed on site to address the turf field water quality requirements. In conclusion, Dewberry believes that sufficient evidence has been provided to CADCD that the synthetic turf system will provide the required water quality improvements over the existing grass field without having to provide additional measures. This has been shown by the ability of the synthetic turf system stone layers and pervious liner to act as a slow release infiltration system and through the reduction of the quantity of fertilizer used on the field. The results from the flow meter report will ensure the effectiveness of the turf field's ability to treat water quality. PROPOSED DESIGN INFORMATION & CALCULATIONS STONE LAYER STORAGE VOLUME COMPUTATIONS LUCKSTONE STONE VOID CHART DRAINAGE AREA MAP IDF TABLE iW Dewberry"' Calculation Shee Designer Date Checker Date Title 5 1 f Job No. Subject _ _AlT:C_ Sheet No.of RA 5 10 1 9'5;6/7 5E Q(//\/ s_ t, z c-__;73pJ 4 1" 3\ 0 \ //C01 V At e 5 A.) r to !orJ LrJ J/ Lvcx 5-it,NE.,= c5r7D/1/4J J 3 11ZfWC., 14 Et.v 4-{ 5-6_ Q0 5 (A Z (3 D Lt # 1 , Z)(° ' 3, 4 (?"' Y1 c FLY Ltca.5— 1°r) ver.um6„fivA )/ gt VoLumf: 0 K 1TR J - U Qet),-- A 30-2A 1-. WP7 AR') ffe 1= 6.7 RA A rEPT APR -22 -2009 10:20 Frnm:LSC - CENTRAL LAB 8047844781 To:804290792A P.2•2 WOK. S 'I'UNE Luck Stone / Charlottesville Last Revision Date : 05/14/2008 Properties: Coarse Aggregates LUCK VDOT VDOT VDOT VDOT Products 5 57 88 78 8P Dry Bulk Specific Gravity 2.951 2.942 2.947 2.924 2.900 S.S.D. Specific Gravity 2.960 2.954 2.960 2.941 2.918 Absorption 0.31 0.40 0.45 0.56 0.62 Unit Weight (pcf) 104.8 106.0 100.4 103.3 103.0 Voids Coarse A. •r-:ate 43.0 45.3 43.3 Flat and Hon! ated 5:1 4.5 1.4 7.8 12.6 6.3 3:1 23.7 11.9 26.8 43.7 35.2 2:1 68.1 67.7 70.0 79.4 Fine Aggregates Products VDOT #10 VDOT #16 Dry Bulk Specific Gravity 2.858 2.851 S.S.D. Specific Gravity 2.894 2.884 Absorption 1.24 1.15 Fine Aggregate Angularity 49.9 (1252 -A)49.0 (1252 -A) Sand Equivalent 71 87 Compaction Weight (pcf) 132.3 1.7 % Moist. 127.7 @ 1.7 % Moist. Source Pro erties Coarse Aggregate: Soundness 0.4 L. A. Abrasion 11.8 Moh's Hardness 6.0 Fine A: ! re s ates: Soundness 5.5 Organic Content 0.0 Clay Lumps & Friable Particles The information contained in this bulletin follows accepted AASHTO or ASTM testing protocols and Is considered accurate, but are made without guarantee. Luck Stone Corp. disclaims any liability Incurred In connection with the use of this data. PO. Box 29682 Richmond, VA 23242 -0682 800 -898 LUCK 804 -784 -6300 Fax• 801-784-6390 www.luckstone.corn IDF Table for Albemarle; County (or City) # 02 Intensities (in /hr)g Dewberry Tc (hr) Tc (min) 2 -Year 5 -Year 10 -Year 25 -Year 50 -Year 100 -Year 0.083 5 5.18 5.91 6.67 7.48 8.04 8.76 0.167 10 4.12 4.79 5.37 6.01 6.45 7.01 0.250 15 3.44 4.05 4.55 5.10 5.49 5.98 0.333 20 2.97 3.53 3.97 4.47 4.83 5.29 0.500 30 2.36 2.83 3.21 3.65 3.98 4.40 0.667 40 1.97 2.38 2.72 3.13 3.43 3.83 0.833 50 1.70 2.06 2.38 2.76 3.05 3.43 1 60 1.50 1.83 2.12 2.48 2.76 3.13 2 120 0.90 1.12 1.35 1.63 1.86 2.18 3 180 0.66 0.83 1.02 1.27 1.47 1.76 4 240 0.53 0.67 0.84 1.05 1.24 1.51 5 300 0.44 0.56 0.71 0.91 1.09 1.34 6 360 0.38 0.49 0.63 0.81 0.97 1.21 8 480 0.30 0.39 0.51 0.67 0.82 1.04 10 600 0.25 0.33 0.44 0.58 0.72 0.92 12 720 0.22 0.28 0.38 0.52 0.64 0.83 18 1080 0.16 0.21 0.28 0.40 0.50 0.67 24 1440 0.13 0.16 0.23 0.33 0.42 0.57 10.0 9.0 Albemarle; County (or City) # 02, VA 8.0 _ 8.0 - 7.0 6 :agi, .6.0 tN c 5.o`. Ti 4.0 c iiii% ohm....._3.0 2.0 1.0 0.0 5 10 15 20 25 30 35 40 45 50 55 60 Duration (Minutes) 1 i .1' 1 ' 4 3 . 09n f/ 1 77,- Is win vs .8 7 i, 0 I:' P 7 I A , CL09, X. N.-- 2A,i;!;:"*7;;,,->. i „ , N ' N x.;----;:--,•.4_,-,ma 7----c.,—PREHi,' il - ' A-7-3.09 AC i i7717 %-- --- - ,-.7: -. 0.55 T—s..1„,-- t,10 MIN. (GRASSED AREA) POST 7 --: - ----3.09 AC ---- 7 :,- - ;' - ---- - , , - - --- • ‘. ,; f11--C 0.80 t1.;;::ii i b Tc,10 MIN. (GRASSED AREA) 1-t. r, ‘‘ ‘NN - \ 571 , • - , ; ; fm rrjiI7 ABTTi' J if- - n , , . ,, „„,,,,,,, - - ,11011,,,,,.- „ --,-,; I L__;--E, .. '7'.-- 4.,,,„: • -Cfirs ::====-,===-.' •=isamse ow% D DATE TITLE SHEET NO. roe*PRE AND POSTewberryMAY2009DRAINAGEAREASee,AD. Dewberry & Davis, Inc.PROJ. NO PROJECT 14180InnslakeDrive, Glen Allen, VA 23060 MONTICELLO HIGH SCHOOLp) 804.290.7957; (t) 804.290.7928 www.dewberry.com 50020623 TURF REPLACEMENT 0 Dewberry' Calculation Shee DesignerM_4' V 1 1""t, DD ate 01 Checker Date Title e..s'f Job No. Subject eo f .62%1A LA TY GAL C,Sheet No.of M1 5F L Chu L O'r Vo4k,i,t4 5F1 = 3, IsscF VOttitAS Yeov I/) 510ts)S- SfN T i-4 10" CoGECT0 5 3‘va 4zz ` ) A VtgACTf. NFx- rro,...) OATS c*vE4C,Q. 5f- CAS f s5-t?A) c TICS z A cDtt.)/v\lAiPt '-p 5F ) (°' ts' 3° Cf c c ?L Syo cc of CALL t' 1 P5- PROPOSED STORMWATER MANAGEMENT ROUTING Job File: P: \50020623 \Tech \SWM Analysis \10INCH.PPW Rain Dir: P: \50020623 \Tech \SWM Analysis\ JOB TITLE Project Date: 4/22/2009 Project Engineer: Scott Kramer Project Title: Monticello High School Turf Replacement Project Comments: S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Table of Contents i Table of Contents MASTER SUMMARY * * * * * * * * * * * * * * * * * * * * ** Watershed Mod. Rational Grand Summary 1.01 Master Network Summary 1.02 NETWORK SUMMARIES (DETAILED) * * * * * * * * * * * * * ** Watershed 2 Executive Summary (Nodes)2.01 Watershed 10 Executive Summary (Nodes)2.02 Watershed 100 Executive Summary (Nodes)2.03 RAINFALL DATA * * * * * * * * * * * * * * * * * * * * * ** Char. 100yr 100 I -D -F Table 3.01 Char. l0yr 10 I -D -F Table 3.02 Char. 2yr 2 I -D -F Table 3.03 TC CALCULATIONS * * * * * * * * * * * * * * * * * * * ** TURF FIELD PRE Tc Calcs 4.01 TURF FIELD POST Tc Calcs 4.03 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Table of Contents Table of Contents (continued) TIME VS.ELEV * ** * * ** * * * * * ** * * **** * ** GRAVEL BED OUT 2 Time -Elev 5.01 GRAVEL BED OUT 10 Time -Elev 5.02 GRAVEL BED OUT 100 Time -Elev 5.03 POND VOLUMES * * * * * * * * * * * * * * * * * * * * * ** GRAVEL BED Vol: Elev- Volume 6.01 OUTLET STRUCTURES * * * * * * * * * * * * * * * * * * * ** Outfall Outlet Input Data 7.01 Individual Outlet Curves 7.03 Composite Rating Curve 7.09 POND ROUTING * * * * * * * * * * * * * * * * * * * * * ** GRAVEL BED Pond E -V -Q Table 8.01 GRAVEL BED OUT 2 Pond Routing Summary 8.03 Detention Time 8.04 GRAVEL BED OUT 10 Pond Routing Summary 8.05 Detention Time 8.06 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Table of Contents iii Table of Contents (continued) GRAVEL BED OUT 100 Pond Routing Summary 8.07 Detention Time 8.08 RATIONAL METHOD CALCS * * * * * * * * * * * * * * * * * ** TURF FIELD 2 Mod. Rational Graph 9.01 TURF FIELD 10 Mod. Rational Graph 9.02 TURF FIELD 100 Mod. Rational Graph 9.03 TURF FIELD PRE C and Area 9.04 TURF FIELD POST C and Area 9.05 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Mod. Rational Grand Summary Page 1.01 Name.... Watershed File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw MODIFIED RATIONAL METHOD Grand Summary For All Storm Frequencies Q = CiA * Units Conversion; Where Conversion - 43560 / (12 * 3600) Area - 3.090 acres Tc = .1667 hrs VOLUMES Freq. Adjusted Duration I Qpeak Allowablel Inflow Storage years C'hrs in /hr cfs cfs 1 ac -ft ac -ft 2 800 3667 2.8470 7.10 7.07 l 215 059 10 800 3833 3.7409 9.32 9.21 1 295 086 100 800 4167 4.8441 12.07 12.02 1 416 126 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Master Network Summary Page 1.02 Name.... Watershed File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw MASTER DESIGN STORM SUMMARY Default Network Design Storm File, ID IDF Storms Rainfall Return Event Type IDF ID 2 I -D -F Curve Char. 2yr 10 I -D -F Curve Char. l0yr 100 I -D -F Curve Char. 100yr MASTER NETWORK SUMMARY Modified Rational Method Network Node= Outfall; +Node = Diversion;) Trun= HYG Truncation: Blank =None; L =Left; R =Rt; LR= Left &Rt) Max Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage Node ID Type Event ac -ft Trun hrs cfs ft ac -ft GRAVEL BED IN POND 2 215 R 2000 7.09 GRAVEL BED IN POND 10 293 R 2500 9.32 GRAVEL BED IN POND 100 415 R 2500 12.07 GRAVEL BED OUT POND 2 205 3500 6.67 487.62 050 GRAVEL BED OUT POND 10 283 4000 7.81 488.22 076 GRAVEL BED OUT POND 100 405 4500 8.63 488.71 138 OUTFALL AT PIPE JCT 2 205 3500 6.67 OUTFALL AT PIPE JCT 10 283 4000 7.81 OUTFALL AT PIPE JCT 100 405 4500 8.63 POINT OF STUDY JCT 2 205 3500 6.67 POINT OF STUDY JCT 10 283 4000 7.81 POINT OF STUDY JCT 100 405 4500 8.63 TURF FIELD AREA 2 216 L 2165 7.10 TURF FIELD AREA 10 295 L 2165 9.32 TURF FIELD AREA 100 417 L 2165 12.07 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Executive Summary (Nodes)Page 2.01 Name.... Watershed Event: 2 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 2yr Tag: 2 NETWORK SUMMARY -- NODES Trun.- HYG Truncation: Blank-None; L =Left; R =Rt; LR =Left & Rt) DEFAULT Design Storm File,ID = Storm Tag Name LULLU Data Type, File, ID = Total Rainfall Depth= 0000 in Duration Multiplier = 0 Resulting Duration 0000 hrs Resulting Start Time= .0000 hrs Step= .0000 hrs End= .0000 hrs HYG Vol Qpeak Qpeak Max WSEL Node ID Type ac -ft Trun. hrs cfs ft GRAVEL BED IN POND 215 R 2000 7.09 GRAVEL BED OUT POND 205 3500 6.67 487.62 OUTFALL AT PIPE JCT 205 3500 6.67 Outfall POINT OF STUDY JCT 205 3500 6.67 TURF FIELD AREA 216 L 2165 7.10 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Executive Summary (Nodes)Page 2.02 Name.... Watershed Event: 10 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 10yr Tag: 10 NETWORK SUMMARY -- NODES Trun.= HYG Truncation: Blank =None; L =Left; R =Rt; LR =Left & Rt) DEFAULT Design Storm File,ID = Storm Tag Name u ni a l(1 Data Type, File, ID = Total Rainfall Depth= 0000 in Duration Multiplier = 0 Resulting Duration 0000 hrs Resulting Start Time= .0000 hrs Step= .0000 hrs End= .0000 hrs HYG Vol Qpeak Qpeak Max WSEL Node ID Type ac -ft Trun. hrs cfs ft GRAVEL BED IN POND 293 R 2500 9.32 GRAVEL BED OUT POND 283 4000 7.81 488.22 OUTFALL AT PIPE JCT 283 4000 7.81 Outfall POINT OF STUDY JCT 283 4000 7.81 TURF FIELD AREA 295 L 2165 9.32 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Executive Summary (Nodes)Page 2.03 Name.... Watershed Event: 100 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 100yr Tag: 100 NETWORK SUMMARY -- NODES Trun.= HYG Truncation: Blank =None; L =Left; R =Rt; LR =Left & Rt) DEFAULT Design Storm File,ID = Storm Tag Name III Il1L]LiLi Data Type, File, ID = Total Rainfall Depth= 0000 in Duration Multiplier = 0 Resulting Duration 0000 hrs Resulting Start Time= .0000 hrs Step= .0000 hrs End= .0000 hrs HYG Vol Qpeak Qpeak Max WSEL Node ID Type ac -ft Trun. hrs cfs ft GRAVEL BED IN POND 415 R 2500 12.07 GRAVEL BED OUT POND 405 4500 8.63 488.71 OUTFALL AT PIPE JCT 405 4500 8.63 Outfall POINT OF STUDY JCT 405 4500 8.63 TURF FIELD AREA 417 L 2165 12.07 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... I -D -F Table Page 3.01 Name.... Char. 100yr Tag: 100 Event: 100 yr File.... P: \5002.0623 \Tech \SWM Analysis \lOinch.ppw Storm... Char. 100yr Tag: 100 Rainfall- Intensity- Duration Curve Time, hrs Intens., in /hr 0830 8.7600 1670 7.0100 2500 5.9800 3330 5.2900 5000 4.4000 6670 3.8300 8330 3.4300 1.0000 3.1300 2.0000 2.1800 3.0000 1.7600 4.0000 1.5100 5.0000 1.3400 6.0000 1.2100 8.0000 1.0400 10.0000 9200 12.0000 8300 18.0000 6700 24.0000 5700 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... I -D -F Table Page 3.02 Name.... Char. l0yr Tag: 10 Event: 10 yr File.... P: \50020623 \Tech \SWM Analysis \lOinch.ppw Storm... Char. l0yr Tag: 10 Rainfall - Intensity - Duration Curve Time, hrs Intens., in /hr 0830 6.6700 1670 5.3700 2500 4.5500 3330 3.9700 5000 3.2100 6670 2.7200 8330 2.3800 1.0000 2.1200 2.0000 1.3500 3.0000 1.0200 4.0000 8400 5.0000 7100 6.0000 6300 8.0000 5100 10.0000 4400 12.0000 3800 18.0000 2800 24.0000 2300 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... I -D -F Table Page 3.03 Name.... Char. 2yr Tag: 2 Event: 2 yr File.... P: \50020623 \Tech \SWM Analysis \lOinch.ppw Storm... Char. 2yr Tag: 2 Rainfall Intensity - Duration Curve Time, hrs Intens., in /hr 0830 5.1800 1670 4.1200 2500 3.4400 3330 2.9700 5000 2.3600 6670 1.9700 8330 1.7000 1.0000 1.5000 2.0000 9000 3.0000 6600 4.0000 5300 5.0000 4400 6.0000 3800 8.0000 3000 10.0000 2500 12.0000 2200 18.0000 1600 24.0000 1300 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Tc Calcs Page 4.01 Name.... TURF FIELD Tag: PRE File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw TIME OF CONCENTRATION CALCULATOR Segment #1: Tc: User Defined Segment #1 Time:1667 hrs Total Tc:1667 hrs S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Tc Calcs Page 4.02 Name.... TURF FIELD Tag: PRE File.... P: \50020623 \Tech \SWM Analysis \lOinch.ppw Tc Equations used... User Defined Tc = Value entered by user Where: Tc = Time of concentration S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Tc Calcs Page 4.03 Name.... TURF FIELD Tag: POST File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw TIME OF CONCENTRATION CALCULATOR Segment #1: Tc: User Defined Segment 41 Time:1667 hrs Total Tc:1667 hrs S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Tc Calcs Page 4.04 Name.... TURF FIELD Tag: POST File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Tc Equations used... User Defined Tc = Value entered by user Where: Tc = Time of concentration S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Time -Elev Page 5.01 Name.... GRAVEL BED OUT Tag: 2 Event: 2 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 2yr Tag: 2 TIME vs. ELEVATION (ft) Time Output Time increment = .0500 hrs hrs Time on left represents time for first value in each row. 0000 1 485.09 485.31 485.92 486.56 487.02 2500 1 487.32 487.51 487.62 487.57 487.24 5000 1 486.69 486.20 485.93 485.82 485.77 7500 485.73 485.71 485.69 485.68 485.67 1.0000 1 485.66 485.65 485.64 485.64 485.63 1.2500 1 485.62 485.62 485.62 485.61 485.61 1.5000 1 485.61 485.61 485.60 485.60 485.60 1.7500 1 485.60 485.60 485.60 485.60 485.60 2.0000 1 485.59 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Time -Elev Page 5.02 Name.... GRAVEL BED OUT Tag: 10 Event: 10 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. l0yr Tag: 10 TIME vs. ELEVATION (ft) Time Output Time increment = .0500 hrs hrs 1 Time on left represents time for first value in each row. 0000 1 485.09 485.39 486.12 486.91 487.56 2500 1 488.05 488.14 488.19 488.22 488.19 5000 1 488.03 487.04 486.24 485.94 485.83 7500 1 485.77 485.73 485.71 485.69 485.68 1.0000 1 485.67 485.66 485.65 485.64 485.64 1.2500 1 485.63 485.63 485.62 485.62 485.61 1.5000 1 485.61 485.61 485.61 485.60 485.60 1.7500 1 485.60 485.60 485.60 485.60 485.60 2.0000 1 485.60 485.59 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Time -Elev Page 5.03 Name.... GRAVEL BED OUT Tag: 100 Event: 100 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 100yr Tag: 100 TIME vs. ELEVATION (ft) Time Output Time increment = .0500 hrs hrs 1 Time on left represents time for first value in each row. 0000 1 485.09 485.47 486.33 487.32 488.12 2500 1 488.26 488.39 488.52 488.63 488.71 5000 i 488.68 488.55 488.33 488.03 486.76 3 7500 i 486.12 485.90 485.81 485.76 485.73 1.0000 1 485.70 485.69 485.68 485.67 485.66 1.2500 1 485.65 485.64 485.63 485.63 485.62 1.5000 1 485.62 485.62 485.61 485.61 485.61 A 1.7500 1 485.61 485.60 485.60 485.60 485.60 2.0000 1 485.60 485.60 485.60 485.60 485.59 a S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Vol: Elev- Volume Page 6.01 Name.... GRAVEL BED File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw USER DEFINED VOLUME RATING TABLE Elevation Volume ft)ac -ft) 485.09 000 488.09 059 488.80 150 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Outlet Input Data Page 7.01 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw REQUESTED POND WS ELEVATIONS: Min. Elev.= 485.09 ft Increment =10 ft Max. Elev.= 488.80 ft OUTLET CONNECTIVITY Forward Flow Only (UpStream to DnStream) Reverse Flow Only (DnStream to UpStream) Forward and Reverse Both Allowed Structure No.Outfall El, ft E2, ft Orifice- Circular 01 TW 485.590 488.800 Orifice - Circular 00 TW 485.590 488.800 TW SETUP, DS Channel S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Outlet Input Data Page 7.02 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw OUTLET STRUCTURE INPUT DATA Structure ID 01 Structure Type Orifice- Circular of Openings 1 Invert Elev.485.59 ft Diameter 8333 ft Orifice Coeff. 600 Structure ID 00 Structure Type Orifice- Circular of Openings 1 Invert Elev.485.59 ft Diameter 8333 ft Orifice Coeff. 600 Structure ID TW Structure Type TW SETUP, DS Channel FREE OUTFALL CONDITIONS SPECIFIED CONVERGENCE TOLERANCES... Maximum Iterations= 40 Min. TW tolerance = 01 ft Max. TW tolerance = 01 ft Min. HW tolerance = 01 ft Max. HW tolerance = 01 ft Min. Q tolerance = 00 cfs Max. Q tolerance = 00 cfs S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Individual Outlet Curves Page 7.03 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw RATING TABLE FOR ONE OUTLET TYPE Structure ID 01 Orifice- Circular) Upstream ID Pond Water Surface) DNstream ID TW (Pond Outfall) WS Elev,Device Q Tail Water Notes WS Elev. Q TW Elev Converge ft cfs ft ft Computation Messages 485.09 00 Free Outfall HW & TW below invert 485.19 00 Free Outfall HW & TW below invert 485.29 00 Free Outfall HW & TW below invert 485.39 00 Free Outfall HW & TW below invert 485.49 00 Free Outfall HW & TW below invert 485.59 00 Free Outfall Upstream HW & DNstream TW < Inv.E1 485.69 03 Free Outfall CRIT.DEPTH CONTROL Vh= .026ft Dcr= .075ft CRIT.DEPTH Hev= .00ft 485.79 12 Free Outfall CRIT.DEPTH CONTROL Vh= .051ft Dcr= .148ft CRIT.DEPTH Hev= .00ft 485.89 26 Free Outfall CRIT.DEPTH CONTROL Vh= .079ft Dcr= .221ft CRIT.DEPTH Hev= .00ft 485.99 45 Free Outfall CRIT.DEPTH CONTROL Vh= .108ft Dcr= .293ft CRIT.DEPTH Hev= .00ft 486.09 68 Free Outfall CRIT.DEPTH CONTROL Vh= .137ft Dcr= .362ft CRIT.DEPTH Hev= .00ft 486.19 94 Free Outfall CRIT.DEPTH CONTROL Vh= .171ft Dcr= .430ft CRIT.DEPTH Hev= .00ft 486.29 1.22 Free Outfall CRIT.DEPTH CONTROL Vh= .206ft Dcr= .494ft CRIT.DEPTH Hev= .00ft 486.39 1.53 Free Outfall CRIT.DEPTH CONTROL Vh= .245ft Dcr= .554ft CRIT.DEPTH Hev= .00ft 486.49 1.83 Free Outfall H =.48 486.59 2.00 Free Outfall H =.58 486.69 2.17 Free Outfall H =.68 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Individual Outlet Curves Page 7.04 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw RATING TABLE FOR ONE OUTLET TYPE Structure ID 01 Orifice- Circular) Upstream ID Pond Water Surface) DNstream ID TW (Pond Outfall) WS Elev,Device Q Tail Water Notes WS Elev. Q TW Elev Converge ft cfs ft ft Computation Messages 486.79 2.32 Free Outfall H =.78 486.89 2.47 Free Outfall H =.88 486.99 2.60 Free Outfall H =.98 487.09 2.73 Free Outfall H =1.08 487.19 2.86 Free Outfall H =1.18 487.29 2.97 Free Outfall H =1.28 487.39 3.09 Free Outfall H =1.38 487.49 3.20 Free Outfall H =1.48 487.59 3.30 Free Outfall H =1.58 487.69 3.41 Free Outfall H =1.68 487.79 3.51 Free Outfall H =1.78 487.89 3.60 Free Outfall H =1.88 487.99 3.70 Free Outfall H =1.98 488.09 3.79 Free Outfall H =2.08 488.19 3.88 Free Outfall H =2.18 488.29 3.97 Free Outfall H =2.28 488.39 4.05 Free Outfall H =2.38 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Individual Outlet Curves Page 7.05 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \lOinch.ppw RATING TABLE FOR ONE OUTLET TYPE Structure ID 01 Orifice- Circular) Upstream ID Pond Water Surface) DNstream ID TW (Pond Outfall) WS Elev,Device Q Tail Water Notes WS Elev. Q TW Elev Converge ft cfs ft ft Computation Messages 488.49 4.14 Free Outfall H =2.48 488.59 4.22 Free Outfall H =2.58 488.69 4.30 Free Outfall H =2.68 488.79 4.38 Free Outfall H =2.78 488.80 4.39 Free Outfall H =2.79 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Individual Outlet Curves Page 7.06 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw RATING TABLE FOR ONE OUTLET TYPE Structure ID 00 Orifice - Circular) Upstream ID Pond Water Surface) DNstream ID TW (Pond Outfall) WS Elev,Device Q Tail Water Notes WS Elev. Q TW Elev Converge ft cfs ft ft Computation Messages 485.09 00 Free Outfall HW & TW below invert 485.19 00 Free Outfall HW & TW below invert 485.29 00 Free Outfall HW & TW below invert 485.39 00 Free Outfall HW & TW below invert 485.49 00 Free Outfall HW & TW below invert 485.59 00 Free Outfall Upstream HW & DNstream TW < Inv.E1 485.69 03 Free Outfall CRIT.DEPTH CONTROL Vh= .026ft Dcr= .075ft CRIT.DEPTH Hev= .00ft 485.79 12 Free Outfall CRIT.DEPTH CONTROL Vh= .051ft Dcr= .148ft CRIT.DEPTH Hev= .00ft 485.89 26 Free Outfall CRIT.DEPTH CONTROL Vh= .079ft Dcr= .221ft CRIT.DEPTH Hev= .00ft 485.99 45 Free Outfall CRIT.DEPTH CONTROL Vh= .108ft Dcr= .293ft CRIT.DEPTH Hev= .00ft 486.09 68 Free Outfall CRIT.DEPTH CONTROL Vh= .137ft Dcr= .362ft CRIT.DEPTH Hev= .00ft 486.19 94 Free Outfall CRIT.DEPTH CONTROL Vh= .171ft Dcr= .430ft CRIT.DEPTH Hev= .00ft 486.29 1.22 Free Outfall CRIT.DEPTH CONTROL Vh= .206ft Dcr= .494ft CRIT.DEPTH Hev= .00ft 486.39 1.53 Free Outfall CRIT.DEPTH CONTROL Vh= .245ft Dcr= .554ft CRIT.DEPTH Hev= .00ft 486.49 1.83 Free Outfall H =.48 486.59 2.00 Free Outfall H =.58 486.69 2.17 Free Outfall H =.68 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Individual Outlet Curves Page 7.07 Name.... Outfall File.... P: \5002.0623 \Tech \SWM Analysis \l0inch.ppw RATING TABLE FOR ONE OUTLET TYPE Structure ID 00 Orifice- Circular) Upstream ID Pond Water Surface) DNstream ID TW (Pond Outfall) WS Elev,Device Q Tail Water Notes WS Elev. Q TW Elev Converge ft cfs ft ft Computation Messages 486.79 2.32 Free Outfall H =.78 486.89 2.47 Free Outfall H =.88 486.99 2.60 Free Outfall H =.98 487.09 2.73 Free Outfall H =1.08 487.19 2.86 Free Outfall H =1.18 487.29 2.97 Free Outfall H =1.28 487.39 3.09 Free Outfall H =1.38 487.49 3.20 Free Outfall H =1.48 487.59 3.30 Free Outfall H =1.58 487.69 3.41 Free Outfall H =1.68 487.79 3.51 Free Outfall H =1.78 487.89 3.60 Free Outfall H =1.88 487.99 3.70 Free Outfall H =1.98 488.09 3.79 Free Outfall H =2.08 488.19 3.88 Free Outfall H =2.18 488.29 3.97 Free Outfall H =2.28 488.39 4.05 Free Outfall H =2.38 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Individual Outlet Curves Page 7.08 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw RATING TABLE FOR ONE OUTLET TYPE Structure ID 00 Orifice- Circular) Upstream ID Pond Water Surface) DNstream ID TW (Pond Outfall) WS Elev,Device Q Tail Water Notes WS Elev. Q TW Elev Converge ft cfs ft ft Computation Messages 488.49 4.14 Free Outfall H =2.48 488.59 4.22 Free Outfall H =2.58 488.69 4.30 Free Outfall H =2.68 488.79 4.38 Free Outfall H =2.78 488.80 4.39 Free Outfall H =2.79 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Composite Rating Curve Page 7.09 Name.... Outfall x File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw COMPOSITE OUTFLOW SUMMARY * * ** WS Elev, Total Q Notes Converge Elev.Q TW Elev Error ft cfs ft ft Contributing Structures 485.09 00 Free Outfall None contributing 485.19 00 Free Outfall None contributing 485.29 00 Free Outfall None contributing 485.39 00 Free Outfall None contributing 485.49 00 Free Outfall None contributing 485.59 00 Free Outfall None contributing 485.69 06 Free Outfall 01 +00 485.79 24 Free Outfall 01 +00 485.89 52 Free Outfall 01 +00 485.99 90 Free Outfall 01 +00 486.09 1.35 Free Outfall 01 +00 486.19 1.88 Free Outfall 01 +00 486.29 2.45 Free Outfall 01 +00 486.39 3.06 Free Outfall 01 +00 486.49 3.65 Free Outfall 01 +00 486.59 4.01 Free Outfall 01 +00 486.69 4.34 Free Outfall 01 +00 486.79 4.65 Free Outfall 01 +00 486.89 4.93 Free Outfall 01 +00 486.99 5.21 Free Outfall 01 +00 487.09 5.46 Free Outfall 01 +00 487.19 5.71 Free Outfall 01 +00 487.2.9 5.95 Free Outfall 01 +00 487.39 6.18 Free Outfall 01 +00 487.49 6.39 Free Outfall 01 +00 487.59 6.61 Free Outfall 01 +00 487.69 6.81 Free Outfall 01 +00 487.79 7.01 Free Outfall 01 +00 487.89 7.21 Free Outfall 01 +00 487.99 7.39 Free Outfall 01 +00 488.09 7.58 Free Outfall 01 +00 488.19 7.76 Free Outfall 01 +00 488.29 7.93 Free Outfall 01 +00 488.39 8.11 Free Outfall 01 +00 488.49 8.27 Free Outfall 01 +00 488.59 8.44 Free Outfall 01 +00 488.69 8.60 Free Outfall 01 +00 488.79 8.76 Free Outfall 01 +00 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Composite Rating Curve Page 7.10 Name.... Outfall File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw COMPOSITE OUTFLOW SUMMARY * * ** WS Elev, Total Q Notes Converge Elev.Q TW Elev Error ft cfs ft ft Contributing Structures 488.80 8.77 Free Outfall 01 +00 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Pond E -V -Q Table Page 8.01 Name.... GRAVEL BED File P: \50020623 \Tech \SWM Analysis \l0inch.ppw m LEVEL POOL ROUTING DATA HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 2 Outflow HYG file = NONE STORED - GRAVEL BED OUT 2 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data Outfall No Infiltration INITIAL CONDITIONS Starting WS Elev 485.09 ft Starting Volume 000 ac -ft Starting Outflow 00 cfs Starting Infiitr. 00 cfs Starting Total Qout=00 cfs Time Increment 0500 hrs Elevation Outflow Storage Infilt.Q Total 2S /t + 0 ft cfs ac -ft cfs cfs cfs 485.09 00 000 00 00 00 485.19 00 002 00 00 95 485.29 00 004 00 00 1.89 485.39 00 006 00 00 2.84 485.49 00 008 00 00 3.79 485.59 00 010 00 00 4.74 485.69 06 012 00 06 5.75 485.79 24 014 00 24 6.87 485.89 52 016 00 52 8.10 485.99 90 018 00 90 9.42 486.09 1.35 020 00 1.35 10.82 486.19 1.88 022 00 1.88 12.30 486.29 2.45 023 00 2.45 13.81 486.39 3.06 025 00 3.06 15.37 486.49 3.65 027 00 3.65 16.91 486.59 4.01 029 00 4.01 18.22 486.69 4.34 031 00 4.34 19.49 486.79 4.65 033 00 4.65 20.75 486.89 4.93 035 00 4.93 21.98 486.99 5.21 037 00 5.21 23.20 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Pond E -V -Q Table Page 8.02 Name.... GRAVEL BED File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw LEVEL POOL ROUTING DATA HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 2 Outflow HYG file = NONE STORED - GRAVEL BED OUT 2 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration INITIAL CONDITIONS Starting WS Elev 485.09 ft Starting Volume 000 ac -ft Starting Outflow 00 cfs Starting Infiltr. 00 cfs Starting Total Qout=00 cfs Time Increment 0500 hrs Elevation Outflow Storage Infilt.Q Total 2S /t + 0 ft cfs ac -ft cfs cfs cfs 487.09 5.46 039 00 5.46 24.41 487.19 5.71 041 00 5.71 25.60 487.29 5.95 043 00 5.95 26.78 487.39 6.18 045 00 6.18 27.96 487.49 6.39 047 00 6.39 29.12 487.59 6.61 049 00 6.61 30.28 487.69 6.81 051 00 6.81 31.43 487.79 7.01 053 00 7.01 32.58 487.89 7.21 055 00 7.21 33.72 487.99 7.39 057 00 7.39 34.86 488.09 7.58 059 00 7.58 35.99 488.19 7.76 072 00 7.76 42.41 488.29 7.93 085 00 7.93 48.83 488.39 8.11 097 00 8.11 55.25 488.49 8.27 110 00 8.27 61.66 488.59 8.44 123 00 8.44 68.07 488.69 8.60 136 00 8.60 74.47 488.79 8.76 149 00 8.76 80.87 488.80 8.77 150 00 8.77 81.51 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Pond Routing Summary Page 8.03 Name.... GRAVEL BED OUT Tag: 2 Event: 2 yr File.... P: \50020623 \Tech \SWM Analysis \lOinch.ppw Storm... Char. 2yr Tag: 2 LEVEL POOL ROUTING SUMMARY HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 2 Outflow HYG file = NONE STORED - GRAVEL BED OUT 2 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration INITIAL CONDITIONS Starting WS Elev 485.09 ft Starting Volume 000 ac -ft Starting Outflow 00 cfs Starting Infiltr. 00 cfs Starting Total Qout=00 cfs Time Increment 0500 hrs INFLOW /OUTFLOW HYDROGRAPH SUMMARY Peak Inflow 7.09 cfs at 2000 hrs Peak Outflow 6.67 cfs at 3500 hrs Peak Elevation 487.62 ft Peak Storage =050 ac -ft MASS BALANCE (ac -ft) Initial Vol 000 HYG Vol IN 215 Infiltration =000 HYG Vol OUT 205 Retained Vol =010 Unrouted Vol =000 ac -ft 000% of Inflow Volume) WARNING: Inflow hydrograph truncated on right side. S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Detention Time Page 8.04 Name.... GRAVEL BED OUT Tag: 2 Event: 2 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 2yr Tag: 2 DETENTION TIMES SUMMARY HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 2 Outflow HYG file = NONE STORED - GRAVEL BED OUT 2 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration APPROXIMATE DETENTION TIME Qout +Infilt. Centroid 3522 hrs Inflow Centroid 2684 hrs Centroid to Centroid 0837 hrs S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Fond Routing Summary Page 8.05 Name.... GRAVEL BED OUT Tag: 10 Event: 10 yr File.... P: \5002062.3 \Tech \SWM Analysis \l0inch.ppw Storm... Char. l0yr Tag: 10 LEVEL POOL ROUTING SUMMARY HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 10 Outflow HYG file = NONE STORED - GRAVEL BED OUT 10 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration INITIAL CONDITIONS Starting WS Elev 485.09 ft Starting Volume 000 ac -ft Starting Outflow 00 cfs Starting Infiltr. 00 cfs Starting Total Qout=00 cfs Time Increment 0500 hrs INFLOW /OUTFLOW HYDROGRAPH SUMMARY Peak Inflow 9.32 cfs at 2500 hrs Peak Outflow 7.81 cfs at 4000 hrs Peak Elevation 488.22 ft Peak Storage =076 ac -ft MASS BALANCE (ac -ft) Initial Vol 000 HYG Vol IN 293 Infiltration =000 HYG Vol OUT 283 Retained Vol =010 Unrouted Vol =000 ac -ft 000% of Inflow Volume) WARNING: Inflow hydrograph truncated on right side. S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Detention Time Page 8.06 Name.... GRAVEL BED OUT Tag: 10 Event: 10 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. l0yr Tag: 70 DETENTION TIMES SUMMARY HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 10 Outflow HYG file = NONE STORED - GRAVEL BED OUT 10 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration APPROXIMATE DETENTION TIME Qout +Infilt. Centroid 3698 hrs Inflow Centroid 2756 hrs Centroid to Centroid 0942 hrs S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Pond Routing Summary Page 8.07 Name.... GRAVEL BED OUT Tag: 100 Event: 100 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 100yr Tag: 100 LEVEL POOL ROUTING SUMMARY HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 100 Outflow HYG file = NONE STORED - GRAVEL BED OUT 100 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration INITIAL CONDITIONS Starting WS Elev 485.09 ft Starting Volume 000 ac -ft Starting Outflow 00 cfs Starting Infiltr. 00 cfs Starting Total Qout=00 cfs Time Increment 0500 hrs INFLOW /OUTFLOW HYDROGRAPH SUMMARY Peak Inflow 12.07 cfs at 2500 hrs Peak Outflow 8.63 cfs at 4500 hrs Peak Elevation 488.71 ft Peak Storage =138 ac -ft MASS BALANCE (ac -ft) Initial Vol 000 HYG Vol IN 415 Infiltration =000 HYG Vol OUT 405 Retained Vol =010 Unrouted Vol =000 ac -ft 000% of Inflow Volume) WARNING: Inflow hydrograph truncated on right side. S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Detention Time Page 8.08 Name.... GRAVEL BED OUT Tag: 100 Event: 100 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 100yr Tag: 100 DETENTION TIMES SUMMARY HYG Dir P: \50020623 \Tech \SWM Analysis\ Inflow HYG file = NONE STORED - GRAVEL BED IN 100 Outflow HYG file = NONE STORED - GRAVEL BED OUT 100 Pond Node Data = GRAVEL BED Pond Volume Data = GRAVEL BED Pond Outlet Data = Outfall No Infiltration APPROXIMATE DETENTION TIME Qout +Infilt. Centroid 4273 hrs Inflow Centroid 2934 hrs Centroid to Centroid 1339 hrs S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Mod. Rational Graph Page 9.01 Name.... TURF FIELD Tag: 2 Event: 2 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 2yr Tag: 2 MODIFIED RATIONAL METHOD Graphical Summary for Maximum Required Storage Method I Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600) RETURN FREQUENCY: 2 yr I Allowable Outflow: 7.07 cfs C' Adjustment: 1.000 1 Required Storage: .059 ac -ft Peak Inflow: 7.10 cfs HYG File: 2 k * * * * * * * * * * * * * * * * * * * * * * * * * * * * Q I Td = .3667 hrs 1 Return Freq: 2 yr Approx. Duration for Max. Storage C adj.factor:1.000 I 1 I I Tc= .1667 hrs I = 4.1242 in /hr I Area = 3.090 acres Q = 10.28 cfs 1 Weighted C = .800 1.1 Adjusted C = .800 1 • 1 Required Storage 1 059 ac -ft 1 Td= .3667 hrs I I I I I= 2.8470 in /hr x x x x x x x 1 x x x x x x x x x x x Q= 7.10 cfs 1 1 x x o Q = 7.07 cfs x o Ix Allow.Outflow) x o I x o NOT TO SCALE 1 x 1 . x o I o 1 x 3673 hrs T S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Mod. Rational Graph Page 9.02 Name.... TURF FIELD Tag: 10 Event: 10 yr File.... P: \50020623 \Tech \SWM Analysis \lOinch.ppw Storm... Char. l0yr Tag: 10 MODIFIED RATIONAL METHOD Graphical Summary for Maximum Required Storage Method I Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600) RETURN FREQUENCY: 10 yr 1 Allowable Outflow: 9.21 cfs C' Adjustment: 1.000 1 Required Storage: .086 ac -ft Peak Inflow: 9.32 cfs HYG File: 10 Q I Td = .3833 hrs 1 Return Freq: 10 yr Approx. Duration for Max. Storage C adj.factor:1.000 I i I I Tc= .1667 hrs I = 5.3752 in /hr 1 Area = 3.090 acres Q = 13.40 cfs 1 Weighted C = .800 1.1 Adjusted C = .800 1 . 1 Required Storage 1 086 ac -ft 1 Td= .3833 hrs 1 1 1 I = 3.7409 in /hr x x x x x x xlx x x x x x x x x x x Q= 9.32 cfs 1 x x o Q = 9.21 cfs x o Ix Allow.Outflow) x o I x o NOT TO SCALE 1 x I . x o 1 o 1 x 3854 hrs T S/N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... Mod. Rational Graph Page 9.03 Name.... TURF FIELD Tag: 100 Event: 100 yr File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw Storm... Char. 100yr Tag: 100 MODIFIED RATIONAL METHOD Graphical Summary for Maximum Required Storage Method I Q = CiA * Units Conversion; Where Conversion = 43560 / (12 * 3600) RETURN FREQUENCY: 100 yr 1 Allowable Outflow: 12.02 cfs C' Adjustment: 1.000 1 Required Storage: .126 ac -ft Peak Inflow: 12.07 cfs HYG File: 100 Q 1 Td = .4167 hrs 1 Return Freq: 100 yr Approx. Duration for Max. Storage C adj.factor:1.000 I I I I Tc= .1667 hrs I = 7.0169 in /hr 1 Area = 3.090 acres Q = 17.49 cfs 1 Weighted C = .800 1•I Adjusted C = .800 1 • 1 Required Storage 126 ac -ft I Td= .4167 hrs 1 1 I I= 4.8441 in /hr x x x x x x xlx x x x x x x x x x x Q= 12.07 cfs I I • 1 x X o Q = 12.02 cfs x o Ix Allow.Outflow) x 0 1 x o NOT TO SCALE 1 x x o 1 0 1 4174 hrs T S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... C and Area Page 9.04 Name.... TURF FIELD Tag: PRE File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw RATIONAL C COEFFICIENT DATA Area C x Area Soil /Surface Description C acres acres Predeveloped 5500 3.090 1.700 WEIGHTED C & TOTAL AREA --->5500 3.090 1.700 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Type.... C and Area Page 9.05 Name.... TURF FIELD Tag: POST File.... P: \50020623 \Tech \SWM Analysis \l0inch.ppw RATIONAL C COEFFICIENT DATA Area C x Area Soil /Surface Description C acres acres Post Developed to Detention 8000 3.090 2.472 WEIGHTED C & TOTAL AREA - - ->8000 3.090 2.472 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 Appendix A A -1 Index of Starting Page Numbers for ID Names C Char. 100yr 100... 3.01 Char. l0yr 10... 3.02 Char. 2yr 2... 3.03 G GRAVEL BED... 6.01, 8.01 GRAVEL BED OUT 2... 5.01, 8.03, 8.04, 5.02, 8.05, 8.06, 5.03, 8.07, 8.08 0 Outfall... 7.01, 7.03, 7.09, 9.01, 9.02, 9.03, 4.01, 9.04, 4.03, 9.05 W Watershed... 1.01, 1.02, 2.01, 2.02, 2.03 S /N:Bentley Systems, Inc. Bentley PondPack (10.00.027.00)3:13 PM 5/20/2009 ADEQUATE OUTFALL ANALYSIS Adequate Outfall Analysis Dewberry used USGS maps to delineate the watershed that drains to the forebay located just north of the stadium (See attached drainage map). An existing 42" Class V reinforced concrete storm drain pipe, oriented at 2.78 %, routes this approximate 47 acre drainage area to the forebay below. An adequate outfall analysis was done to ensure that this pipe can handle the drainage being routed to it. A conservative time of concentration of 20 minutes was used for this drainage area (see attached time of concentration spreadsheet), and a conservative average `C' factor of 0.80 was also used (1/2 acre lots within Hydrologic Soil Group C). The intensities for the 2 and 10 year storms are 2.97 and 3.97 in/hr respectively. When these numbers are plugged into the rational formula the 2 and 10 year storms result in a discharge of 112 and 150 cfs respectively. A 42" reinforced concrete pipe oriented at 2.78% can handle about 167 cfs at full discharge. This outfall appears to be adequately sized to handle the drainage being routed to it. The 2 and 10 year peak discharges from this project site will be reduced to below existing levels in order to meet water quantity requirements. This reduction in flows will alleviate some of the demand being placed on this existing outfall pipe. This pipe discharges directly to a stormwater management forebay and requires no adequate channel analysis beyond the outfall of this pipe. SAL_ AA f- C_ D. go l F q- ,A /de oNs Fes.I-tAi/1f A- 9 Mc C,2 0. To l f5 q-1-)(41-)2O 1.50 CC5 1 F ,fox_ I j s x A.4'../7/4// 1111 DA r 47 AC Is, 0.80 i_1: .J rj 1 x 010 :.. otr....44,,-,,,,,,,,,. Ai .4,.,, 14 „-,„ '\''., ';' ', Ili ,' s /,, / l , : -. ,-\:"1'''' t vlt ti \1 t y 7; 1--., c , V,i , ', ' ' .'i "-,,,k 1' i ,t f\ 4 } f f , f ) DRAINAGE AREA A=47 AC 0.80 TC=20 MIN. r ABEL 0'300'600'f ACRE MR MINN C DATE TI SHEET NO.1 ! Dewl3erry ADE QUATE OUTFALL MAY 2009 DRAINGE AREADewberry & Davis, Inc.PROJ. NO. PROJECT 41801nnslake Drive, Glen Allen, VA 23060 MONTICELLO HIGH SCHOOLp) 804.290.7957; (f) 8044 290 .290.7928 www.dewbeny.com 50020623 TURF REPLACEMENT e el \ Ili d oMO I a I cr ui I , -.- R a CC MIH J 0 <® e g) 0 w 0 I- o o > O ° u f /o I < / o <u A J yr 0 oO2 NO m k D k ° u 0 le 0i Plat 0 I C:I 4S I ' Maw up Chapter 6 - Hydrology Appendix 6H -3 Runoff Curve Numbers for Urban Areas MEP Cover description Curve numbers for hydrologic soil groups IMO Cover type and Average percent A B C D hydrologic condition impervious area Fully developed urban areas (vegetation established) Open space (lawns, parks, golf courses, cemeteries, etc.) Poor condition (grass cover <50 %)68 79 86 89 Fair condition (grass cover 50% to 75 %)49 69 79 84 Good condition (grass cover > 75 %)39 61 74 80 Impervious areas: Paved parking lots, roofs, driveways, etc. excluding right -of -way)98 98 98 98 Streets and roads: Paved; curbs and storm drains (excluding right -of -way)98 98 98 98 Paved; open ditches (including right -of -way)83 89 92 93 Gravel (including right -of -way)76 85 89 91 Dirt (including right-of-way)72 82 87 89 Western desert urban areas: I 1111P Natural desert landscaping (pervious areas only)63 77 85 88 Artificial desert landscaping (impervious weed barrier, desert shrub with 25- to 50-mm sand or gravel mulch and basin borders)96 96 96 96 Urban districts: Commercial and business 85 89 92 94 95 Industrial 72 81 88 91 93 Residential districts by average lot size: MINI 0.10 or less (town houses)65 77 85 90 92 1 /4 acre 38 61 75 83 87 3 acre 30 57 72 81 86 4 k 1 /2 acre 25 54 70 80 85 1 acre 20 51 68 79 84 2 acre 12 46 65 77 82 Developing urban areas Newly graded areas (pervious areas only, no vegetation)77 86 91 94 Idle lands (CNs are determined using cover types similar to those in Table 6 11). I Comments: 1 Average runoff condition, and l = 0.2S 2 The average percent impervious area shown was used to develop the composite CNs. Other assumptions are as follows: impervious areas are directly connected to the drainage system, impervious areas have a CN of 98, and pervious areas are considered equivalent to open space 1 p in good hydrologic condition. If the impervious area is not connected, the SCS method has an adjustment to reduce the effect. 3 CNs shown are equivalent to those of pasture. Composite CNs may be computed for other combinations of open space cover type. Source:SCS -TP -149 1 of 1 VDOT Drainage Manual UMW Adequate Outfall i ;' .,r:. ' /Y.....,, „ i,"r " ':in -nra'%(Y,.':r,., ., x „ /., i rz ter. /,. F e .:d,,,.,.., arr .,..r ,. .Lw /:, . e w ;_.,.,/ yyy r w. W/+ rrr •.,-. r , ,. f. ri..ui -. rr.r „., /; r .,i!,,, rii ' n>h7(7.tirt a .r v. ... „j, r. /i r ., , f ., fa+'.,. F..yyr ljj Friction Method Manning Formula Solve For Full Flow Capacity ( r, ., v . ,t.rs Yr , . s.r, . /ar., rrs /r.. , .i Roughness Coefficient 0.013 Channel Slope 2.78000 Normal Depth 3.50 ft Diameter 3.50 ft Discharge 167.74 ft /s g ,-r /3.. Y ^ r r.r /:i's”r3"':.;, , -y9'-Viz' r n Discharge 167.74 ft' /s Normal Depth 3.50 ft Flow Area 9.62 ft Wetted Perimeter 11.00 ft Top Width 0.00 ft Critical Depth 3.43 ft Percent Full 100.0 % Critical Slope 0.02485 ft/ft Velocity 17.43 ft/s Velocity Head 4.72 ft Specific Energy 8.22 ft Froude Number 0.00 Maximum Discharge 180.44 ft' /s Discharge Full 167.74 ft /s Slope Full 0.02780 ft/ft Flow Type SubCritical e b r p F i/4ry Y;Gr.'i ` rzf g F 9 Fy . fpr' 1 q r. .r r.4s`.,'s.?',.F.. _f Downstream Depth 0.00 ft Length 0.00 ft Number Of Steps 0 fx Z 0 P.t”5 fie ,-R. E9 /`a 3fi ° Upstream Depth 0.00 ft Profile Description Profile Headloss 0.00 ft Average End Depth Over Rise 0.00 °A Normal Depth Over Rise 100.00 % Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 5/19/2009 3:39:19 PM 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1 -203- 755 -1666 Page 1 of 2 Adequate Outfall rte; -r r; . Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 3.50 ft Critical Depth 3.43 ft Channel Slope 2.78000 Critical Slope 0.02485 ft/ft Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.071.00] 5/19/2009 3:39:19 PM 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1- 203 - 755 -1666 Page 2 of 2 SUPPORTING ILLUSTRATIONS r G74.,,v..:%- .., ` .01-,v tl f r t•f j "r re". i y - f iv -r i hf 4 p f may' f ,r " rf r! f s, /7-:--„77 ,,..'•-.lr s f$ fi P.,.f 1 .,e..._.. r `/ S T Ed i INTERSTATE 64 ; f W r i j ' r 5J7. f l f • q, ,' //;,', 2 rrf; II i t ' 1 , 4 t %1 rr {- 9 Q1 1 f y p l l PNCrNE Frr r r J ‘,..,,t t l m TE4£o j r f '] d t i r C Jti r r 1 f 7r7 ynoCi Sa o SITE t faro Chaftxl ,677 r 5t5 ' 1 0 ij ter" J , r ow 1 0 2000 4000 DATE TITLE SHEET NO. Dewberry APR 2009 VICINITY MAP Dewberry & Davis, Inc. 41801nnslake Drive, Glen Allen, VA 23060 p) 804.290.795, (fl 804.290.7928 MONTICELLO HIGH SCHOOL g . 1PROJ. NO. PROJECT www.dewbeny.com 50020623 TURF REPLACEMENT 2.5" SYNTHETI I SYNTHETIC TURF 12.5" SYNTHETIC TURF SURFACE TURF SURFACE EXISTING 2" FINISHED TRACK 2 " FINISHED STONE ( #8)EXISTING STONE ( #8)1.5% SLOPE 1.5% SLOPE— IL TRACK - - J4BAS 1.5% SLOPE 1. S E STONE ( #57) GEOTEXTILE I J PERIMETER CURB COMPACTED MIRAFI 140N) PERIMETER CURB SLOPED EXISTING FOR DRAINAGE FILTER FABRIC ill10" HDPE PERFORATED : 10" HDPE PERFORATED COLLECTOR COLLECTOR GENERAL SPORTS VENUE TYPICAL FIELD SECTION NTS SYNTHETIC TURF EX FACE O2.5" SYNTHETIC SURFACE TO BE SURFACE COURSE TURF SURFACE EXISTING 2" AT DITCHLINE =CONCRETE PROPOSED GRADE GLUED TO EXISTING 1"BM -2 4" BASE ELV. 488.80 2" FINISHED SM -2A ASPHALT BITUMINOUS BASE STONE (#57)STONE ( #8) APPROXIMATE EXISTING L 2" CLEARANCE TRACK5% SLOPE 1 57 SLOPE szsranrm.<.+- z.m,;razrsr s+yat"aa . rsrsarss. r+ casrrz^rcnstx.^n ,.ar2rss , cT P - COMPACTED EXISTING 6" 21A EXISTING 6" 21A SUBGRADE SLOPED f•M '''''•:'" f STONE BASE STONE BASE FOR DRAINAGE 3 i> - i EXISTING CONCRETE CURB GEOTEXTILE I "` - "-FILTER FABRIC 8" WIDE X 6" DEEP MIRAFI 140N)y 3'REINFORCED WITHr EXISTING STONE TRENCH DRAIN WITH 57 4 REBAR)IIM • VARIES UT4 . , 'C _`I TRENCH - - -BOTTOM 1 AND PERFORATED IPS 6"STONE ELV. 485.09 I UNDERDRAIN TO STOTORMM SYSTEM BENEATH CURB 6' 10" HDPE PERFORATED BASE STONE ( #57)2PIPE I 12.6' NOTES: 1. CONTRACTOR SHALL USE WASHED STONE FOR SYNTHETIC TURF FIELD. 2. THE 2.5" SYNTHETIC TURF SURFACE, 2" FINISHED STONE (#8), 4" BASE STONE ( #57), AND THE COMPACTED SUBGRADE ARE TO BE SLOPED AT A 6" AT TIE -IN POINT, 1.5% SLOPE FROM THE CENTERLINE OF THE FIELD AND FROM THE EDGE OF 17 AT CORNERS OF THE TRACK TO THE PROPOSED TRENCH ALONG THE SIDELINES.FIELD AND 6" AT 3. THE BOTTOM OF THE TRENCH ALONG THE SIDELINES IS TO REMAIN FLAT AT FIELD GOAL POSTS. A CONSISTENT ELEVATION (ELV. = 485.09). THE BOTTOM OF THE TRENCH WILL SLOPE UP AT 1.5% AFTER THE TRENCH TURNS 90 DEGREES AND IS GENERAL SPORTS VENUEROUTEDPERPENDICULARTOTHESIDELINESTOWARDSTHEFIELDGOAL POSTS.TYPICAL SIDELINE FIELD SECTION 41SEE ° EXISTING UNDERDRAIN DISCONNECT DETAIL" ON SHEET C24A FOR AT 10" PIPE CONNECTIONREDIRECTIONOFDRAINAGEFROMTHEEXISTINGUNDERDRAIN. NTS 2.5" SYNTHETIC SYNTHETIC TURF 2" FINISHED TURF SURFACE SURFACE BE STONE (8)GLUED 04" BASE CONCRETE STONE (#'57) EXISTING GRASS SURFACE WA a Ad1N.ia.£itiSG'K-Y3 2 i 3: ats- 'PtAi12ii3,3,4 f,iv* .16 {zY fit #Are,r. i1 1 XFfei E COMPACTED e 4. ,SUBGRADE 3' GEOTEXTILE CONCRETE CURB 8" WIDE X 6" DEEP MIRAFI 140N)REINFORCED WITH VARIES NI 4 REBAR) 6" OF 21A STONE l BENEATH CURB 10" HDPE PERFORATED 2' BASE STONE (1157) PIPE I 5' GENERAL SPORTS VENUE TYPICAL END ZONE FIELD SECTION 6" AT TIE -IN POINT, 17" AT CORNERS OF AT 10" PIPE CONNECTION FIELD AND 6" AT NTS FIEE GOAL POSTS. P Deuv DATE T SHEET N0. TYPICAL SYNTHETIC MAY 2009 TURF PROFILE Dewberry & Davis, Inc.PROJ. NO. PROJECT F4180InnslakeDrive, Glen Allen, VA 23060 MONTICELLO HIGH SCHOOLp) 804.290.7957; (f) 804.290.7928 www.dewbeny.com 50020623 TURF REPLACEMENT saen,sl var rr s 4 - I'4 t j f qFl A'.t fir .'. x SP b6B0 1 I.9Fi rii eam i l Atr }s' .mm4i, . zi 1 5 ' y! s Vi 6 ,i,•`.) \ ' , `.,` \ '\ 4 .r---.. e 0 r_ f qL J F \ '2,, x a i fit 1Ofl=77 - 7 f O DATE TITLE Dewberry SHEET NOMAY2 PROPIPE 2009 LAYOUT Dewberry & Davis, Inc.PROJ. NO. PROJECT FIG4180keDrive, Glen p en, VA 23060 MONTICELLO HIGH SCHOOL 3Jp) 804.2904.290.7957; (f) 804.290.7928 www.dewberry-corn 50020623 TURF REPLACEMENT EXISTING SOILS INFORMATION l`19 roNt f O NO E-Y4 Zo,nc. 3 O to 041,\..Za+nz_ ro' PQ.** Scale 1"= 50'Test Location Percolation Test Locations Turf Field Monticello High School Albemarle County, Virginia Gooch Engineering & Testing, Inc. 1821 Broadway Street Percolation Test Results Turf Field Monticello High School Albemarle County, Virginia Hole Depth of Material Description in Test Zone Percolation Test (fl.)Rate (in./hr.) 1 1.0 Red -brown clayey silt 0.125 Fill) 2 1.0 Red -brown clayey silt 0.1875 Fill) 3 2.0 Red -brown clayey silt with cobble -size 0 greenstone fragments Fill) 4 1.0 Red -brown clayey silt 0.125 Fill) 5 1.0 Light green clay 0 Fill) 6 2.0 Red -brown clayey silt with cobble -size 0.0625 greenstone fragments Fill) 7 5.0 Red -brown clayey silt with cobble -size 0.25 greenstone fragments Fill) 8 5.0 Red -brown clayey silt 0 Fill) 9 5.0 Red -brown clayey silt 3.0 Fill) 10 5.0 Green clayey silt with cobble -size greenstone 0.0625 fragments Fill) EXISTING SITE ANALYSIS Existing Conditions Analysis Dewberry obtained as -built drawings from the Client to gain an understanding of the drainage and stormwater management for the project site. Upon review of the provided information, Dewberry identified a stormwater management pond that currently serves all of the Monticello High School property. A stormwater management forebay, located south of the pond, serves the football field and the areas adjacent to it, which then drains into the stormwater management pond. The forebay and pond appear to be in excellent condition and functioning as they should be. The drainage from the synthetic turf field will tie in to the existing storm drain system at the two inlets located along the sidelines at midfield. From here these two inlets tie into two other inlets located adjacent to the north end zone, and from there those two inlets tie in to a single inlet located at the northern most point of the field within the limits of the track. The water then outfalls through a 42" RCP into the stormwater management forebay. The attached sheets are the as -built plans that show the football stadium and surrounding areas, including the area south of the school property and the stormwater management pond and forebay to the north. P:\50020623 \Tech\S WM Analysis\Existing Conditions.doc i„I 1 1 l I m _ I >'I 0 g e x S av E Q NN. 1111 - yam. . 9, 4 5 b 1 _ I u;i 8 l ":+ i ce zi a 1oa AA I v t 4 1_._ ;`rr (W ..` 111 u,-- C R ©1.. ....•. ::...lawewWC,a4utlilaW, T... 11 fi 1 -4 m Q Y.°'; 0 liRAIlii.,1; '6, 4.,1. el, Nit i IN 11 r €1 11; at i:r•E 1111 .; '111 111 11 "'g . 11 ,° . 111 q y 111. 1111:.... •1111 ::::::_ ;;:a ; „ _ 1111 1111 111 i,:::<. . ;..:..:.. 11 ;,;,;F:' 1,,1,1,1 „y111.1_ s '11-11, e,i rte ", -;i.'s x , xr-- .-- ,—: * N • •. ‘,., .,,,,\\\\\\1. 11) LA Si C ji.f . . C3 . : :-.1::1 ill, ' ''A1.\ , 'r 1!1 Z VW. '' 11, -- , , : : : : :: ( 4: 3 : ; ''' A' ' 8 1.2 ii}4 jl0A42_111, 0 4104 a1t4r0 y . u7e a', it ' » \ *J? e ti m 4 4 ' c Y J.i. NAB—i 0 I "; " a F? n° p > ©/ 0 i' i 1 k I'j 1y i .k tl g A a / : u fy A dir Q, O Y 4 z::. ' 11 a # `i `i.. 5XN/T,q, sew a -.FPI 4 1W K.f Rn °y i 1111L'- ,'1 . 1 , 1 : » °1 .«: 1111. .. . »„<....., - : il.,.° : 1 11; . tv* =.r n*e.... g i.1 C MONTICELLO HIGH SCHOOL i1 8lz 1 44111 M ij t 1 ,, 11 i 6 a 11111up I ALBEMARLE COUNTY, VIRGINIA f 19 r ____________ j L v _ u oS J ///Q V fit 44;s:,'• N i 0 II y /,‘ i in , Y 4 RR cm Nom K _i `R I ..,, Allw , 7:934440 Ax Tael x x iUiriii'liij • I 1 \ \ \ \ \ \ \ 4 ;m J i ; v H 1 1 2,i i I , i 42 U J 1 X T i i ii 7.7 ' 1 11 v" 1 D I J m;q ilSt00R c w lw!! _ ° —r iii LR' I Ilk" 3.I i •ii 01 l0.,6 W1114„,4 - - x i - a»nbca T g,r,<-;"43:.;a M . \ 7"-Nn2w Y „L_________._40\0_,:.:, \tio, ii...‘ \ ° A.m 1 :. f I: .' ; i i i 1 . II 0 It ' l ' --",..— Iiii 5 :j,A 1\x"1 all to 111P Rt 11' wie . ll V q--''''.q 8>\..):if, g i g p immusuem R w \ N - ,, tV 11.; a p..k, \ n.. 6i, -' 4%71r4;,...,,,,,,,Lib' \ \w N u R y I S, s , N Tit i t11 e 0 i "'gg ex I1 o MONTlCELLO HIGH SCHOOL i IHIIIIhIIIIIII 1 1 1 1 . i A •g m i J e v'w L- „- :.p__,,__—TT - i j i I 11 J 1 j i l 1 t ( j j1 g i IIiiI f1 I j I I 1 \, i i 1 l III Illt; - I 1 N j 6ctN I 1 1I A a m p u T i fi \ I a° I 1 ii1 1,t A. R 1 s V. I I 0 r A gj 8 I y`\1 I 4 l II .I,Pi' p b jij i k1ff11 r %I r kf a 1 1 i'f/ III - , 11 , 11(-11 /1 /l1xf /1l /.1l1, /alt 1 is q iip1 ,:t g f,,€?,JI / 'F 1 f .FR rf „, '',' ''''t.' // 'u i ' hav 4: p 1 z/ .1c, 4--;, ,', irr.,. .,....,,,,,„..i...A 5 7 ' .,/ 1), i',,, - 11 l' g I( 1,, - I A Jj 1 't I '' 1 I\ li i g i 7 C; ' r/ 'i• y Pi I I .y 3 , pp I f .Al mss. .SSI__ -'_.4CIta'" C)MONTICELLO HIGH SCHOOL N 111 114 1111111 1 0 1 11 R " FiC)J 13 ALBEMARLE COUNTY, VIRGINIA m g l it IIIIIIIIL y ;9