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HomeMy WebLinkAboutWPO201700070 Other 2019-01-25Ivy Road Sidewalk Improvements Project # 0250-002-R98 Hydraulic Design Report Albemarle County, Virginia December 3, 2018 Prepared by: Kimley-Horn & Associates, Inc. 1700 Willow Lawn Dr., Suite 200 Richmond, VA 23230 Owner: Albemarle County Kimley-Horn and Associates, Inc. Richmond,VA Kimley)))Horn 2 This document, together with the concepts and designs presented herein, as an instrument of service, is intended only for the specific purpose and client for which it was prepared. Reuse of and improper reliance on this document without written authorization and adaptation by Kimley-Horn and Associates, Inc. shall be without liability to Kimley-Horn and Associates, Inc. TABLE OF CONTENTS DRAINAGE NARRATIVE APPENDIX A: SITE INFORMATION USDA Soil Survey Map & Data Recommended Maximum Water Velocities per AASHTO Soil Type APPENDIX B: DRAINAGE AREA MAPS Pre -Development Drainage Area Map Post -Development Drainage Area Map APPENDIX C: WATER QUALITY Water Quality Compliance Summary Water Quality Compliance Calculations APPENDIX D: WATER QUANTITY Water Quantity Compliance Summary Applicable Storm Sewer and Hydraulic Grade Line Computations (See Appendix F for Additional Applicable Computations) APPENDIX E: DETENTION PIPE DESIGN Hydraflow Model - Hydrographs and Reports APPENDIX F: STORM DRAINAGE SYSTEM CALCULATIONS Storm Sewer and Hydraulic Grade Line Computations Curb Inlet Spread and Throat Length Calculations Grate Inlet Calculations 4 INTRODUCTION Project Description Ivy Road is an existing three -lane undivided roadway with a mix of narrow shoulders, curb, and curb and gutter between Old Ivy Road (Route 601) and the Route 29/Route 250 Bypass interchange. Ivy Road generally runs east to west from the Charlottesville Business District to Crozet. Ivy Road is an important transportation corridor, serving as a connection between the Charlottesville Business District and the Route 29/Route 250 Bypass. Ivy Road (Business Route 250) is functionally classified as Urban Principal Arterial and is on the National Highway System (NHS). This project will provide bicycle lanes and concrete sidewalk along the south side of Ivy Road for approximately 1,800 linear feet from the intersection with Old Ivy Road to the intersection with Stillfried Lane. Project Area The applicable project site ("A -Site") is 1.93 acres. This area is likely to be disturbed during construction. See Appendix B for more information. ExistingDrainage Conditions In the existing condition, all stormwater runoff within the project limits is ultimately captured by curb inlets, grate inlets, or end sections and conveyed via storm sewer systems to outfalls located off -site. Two analysis points ("outfalls") have been identified at locations that collectively include all impacted drainage areas. One analysis point (Outfall A) is located within a storm sewer pipe, immediately upstream of its discharge point. The other analysis point (Outfall B) is located within an existing pipe network that is well upstream of the ultimate discharge point of the storm sewer system. Outfall A is located within the Moores Creek watershed. Outfall B is located within the Rivanna River — Meadow Creek watershed. • Outfall A o This outfall is an existing 36" concrete pipe leaving existing structure #452. The pipe discharges into a channel on the western side of Reed Lane. o In the existing condition, this outfall collects stormwater runoff from along Ivy Road, west of the high point near station 122+00. o Additional off -site runoff reaches this outfall from areas north of the Buckingham Branch Railroad tracks. This runoff crosses the railroad tracks via culverts that discharge into an existing ditch along the north side of Ivy Road. The stormwater in the ditch then enters the existing storm sewer system that leads to the outfall via pipes that cross Ivy Road to the south. There appears to be an existing pipe underneath Ivy Road near station 117+50 that has a washed-out headwall. This likely creates a flooding condition as the backed -up water must then reach the next downstream pipe crossing near station 116+00. o Additional off -site runoff reaches this outfall from the developments to the south of Ivy Road. This runoff enters the existing storm sewer system that leads to Outfall A. o There are anecdotal reports of flooding along the route of the existing storm sewer network leading to Outfall A. Analysis shows that parts of this system are significantly over -capacity in the existing condition with an HGL that is above the ground elevation. See Appendix D for more information. • Outfall B o This outfall is an assumed existing 42" concrete pipe leaving an assumed junction between the existing 30" concrete pipe from existing structure #409 and the existing 42" concrete pipe from existing structure #440. The extension of the existing 42" concrete pipe and the junction were not verified via survey due to inaccessibility. However, the Charlottesville GIS website shows that these two branches of the existing storm sewer network combine and then continue east towards downtown. The assumed junction is noted as existing structure #000 on the plans. This condition is assumed across the existing and proposed analyses and does not influence the outcome of the proposed stormwater management improvements. The 10-year post -development Q is less than the 10-year pre - development Q at the analysis point. o In the existing condition, this outfall collects stormwater runoff from along Ivy Road, east of the high point near station 122+00. o Additional off -site runoff reaches this outfall from areas north of the Buckingham Branch Railroad tracks. This runoff either crosses the railroad tracks via culverts that discharge into an existing ditch along the north side of Ivy Road, or is captured in an existing storm sewer network that runs along Old Ivy Road and enters the survey limits at existing structure #440. The stormwater in the channel along the north side of Ivy Road flows east to the intersection between Ivy Road and Old Ivy Road. An existing culvert or pipe in this area, which would be an inlet for the accumulated ditch stormwater, could not be found. Therefore, it must be buried if it exists (In this case, the stormwater in the ditch would eventually overtop the channel bank along Old Ivy Road and enter the existing storm sewer network at existing structure #439). Anecdotal reports of the existing conditions in this area suggest that this occurs today. o Additional off -site runoff reaches this outfall from the developments to the south of Ivy Road, all the way up to the peak of Lewis Mountain. This runoff enters the existing storm sewer system along Ivy Road that leads to Outfall B. o Analysis shows that the existing storm sewer system that leads to Outfall B is over -capacity in some pipes along Ivy Road, with an HGL that is above the ground elevation. This outfall was only analyzed along the existing storm sewer trunk line on the southern side of Ivy Road that enters the outfall junction via the existing 30" concrete pipe. o Some assumptions were made in this analysis due to inaccessible inverts within some existing structures. o Analysis of the existing storm sewer trunk line along Old Ivy Road was not completed due to the insignificance of project improvements contributing to the 6 drainage area reaching Outfall B from that branch (There is only 0.01 acres of new impervious area within a total drainage area of 39.07 acres). See Appendix D for more information. PROPOSED DRAINAGE IMPROVEMENTS Overview In the post -development condition, all stormwater runoff will continue to be captured by either an existing or proposed inlet structure and then conveyed via existing or proposed storm sewer to one of two outfall points. The proposed drainage improvements are as follows: • Outfall A o Proposed curb inlets will be installed to capture runoff from the project site. These inlets are routed via proposed storm sewer to detention pipes between structures 3-4 and 3-6, which control the design storm outflow and then discharge into the remainder of the storm sewer network. o Structure 3-3 captures runoff that was entering the existing storm sewer system at structure EX. 313-8. Since it has been diverted into the Detention System A at the upstream end of the storm sewer network, there is a slight increase in flow in the existing pipe network upstream of EX. 313-8. However, these pipes remain under capacity. The existing pipe network downstream of EX. 313-8 will see a reduction in flow due to this design. o The existing storm sewer trunk line between structures 313-8 and the outfall at structure #452 is over capacity, however analysis shows that the HGL from this system does not back up into and affect the proposed detention system during the design storm. • Outfall B o Proposed curb inlets will be installed to capture runoff from the project site. These inlets are routed via proposed and existing storm sewer to a detention pipe between structures 4-2 and 4-3, which controls the design storm outflow and then discharges into the remainder of the proposed storm sewer network. Shortly thereafter, it ties -in to the existing storm sewer network. o A proposed curb inlet top is to be installed at structure 5-1 to replace the existing grate inlet top at this location. This will allow the inlet to adequately capture runoff from the road based on the proposed design. o A grate inlet and storm sewer connection underneath Old Ivy Road is proposed near station 134+25. This will give any stormwater that was ponding in this area in the existing condition an inlet into the storm sewer network it was likely intended to drain into. The proposed grate inlet does not fully mitigate the ponding issue in this area under the design criteria (10-year storm with 50% clogging). However, it improves the existing condition and gives stormwater runoff an inlet where there is none currently. Methodology The proposed drainage system is designed to collect, detain, and convey the stormwater runoff adequately and improve the existing drainage conditions when full improvements are not practical. Inlet and storm sewer capacities and hydraulic grade line calculations were performed using the Rational method. GEOPAK Drainage software was used to analyze curb inlet capacity under a design storm intensity of 4 inches/hour. Grate inlet capacity was calculated manually via a spreadsheet using the 10-year design storm and VDOT Drainage Manual practices. StormCAD software was used to analyze storm sewer capacity and the hydraulic grade line under a 10-year design storm. HGL calculations were also performed with VDOT methodology. However, the VDOT numbers were judged to be too extreme based on the nature of the existing storm sewer inadequacies. The StormCAD HGL calculations were used for design purposes, because they more closely resemble observed conditions. Inlet and storm sewer calculations are presented in Appendix F. Times of concentration for overland flow were calculated using the Seelye method. Times of concentration for shallow concentrated flow were calculated using the TR-55 method. Times of concentration for channel flow were calculated using the Kirpich method. Times of concentration for off -site storm sewer were calculated manually, assuming an average velocity of 6 ft/s. Stormwater runoff calculations for the detention pipes were performed using the Rational Method. Because the proposed detention pipes are in -line with the rest of the storm sewer networks, Rational methodology was maintained to more accurately analyze the conditions at Outfalls A and B. The Modified Rational Method was employed at Outfall A to ensure adequate volume was detained, due to the increased risk of flooding downstream per the nature of the existing storm sewer system. Detention pipes were designed to detain enough stormwater so that each existing storm sewer pipe downstream of the detention systems would convey a smaller post -development Q than pre -development Q up until, and including at, the analysis points. Detention pipes were also designed to contain the 100-year storm within the pipes and account for the HGL elevation of the downstream storm sewer as the tailwater condition. Detention System A was analyzed using HydroCAD software. Detention System B was analyzed using Hydraflow Hydrographs Extension software. The resulting models and calculations are presented in Appendix E. Both Outfall A and Outfall B have offsite areas that drain to the project site. Several of these offsite developments have detention systems to control the runoff from their sites. When available, the outflow from these systems was used in the analysis of the proposed storm system along Ivy Road. When computations for these detention systems was unavailable, the runoff from these sites was ignored in the quantity computations, as the peak runoff from these sites would occur much later than the peak runoff from on -site, and therefore have no measurable impact on the performance of the proposed systems. Design Parameters Design Storms: 2-Year; 10-Year; 100-Year Manning's n-Values: Use n-Value Concrete Pipes 0.013 Pavement/Gutter Flow 0.015 CN Values: Land Cover A -Soils B-Soils C-Soils D-Soils Forest/Open Space 30 55 70 77 Managed Turf 39 61 74 80 Impervious 98 98 98 98 B, D, and E Factors: Return Period B D E 2-Year 49.020 10.500 0.820 10-Year 46.950 9.500 0.730 100-Year 31.090 5.000 0.550 Source: GEOPAK Drainage Library — Rainfall Data for Albemarle County Minimum Pipe Size: 15" Minimum Proposed Pipe Slope: 0.30% WATER QUANTITY COMPLIANCE This project must comply with part IIB of the VSMP regulations, which stipulates post - development stormwater runoff must meet Channel Protection criteria and Flood Control criteria. These criteria are addressed at each outfall as follows: • Outfall A is a man-made existing concrete storm sewer pipe. Therefore, this outfall meets Channel Protection criteria because concrete pipe is non -erosive. Outfall A utilizes a stormwater detention pipe to achieve Flood Protection compliance. The overall 10-year Q in the post -development condition is 149.61 cfs, which is less than the 153.83 cfs in the existing condition. • Outfall B is a man-made existing concrete storm sewer pipe. Therefore, this outfall meets Channel Protection criteria because concrete pipe is non -erosive. Outfall B utilizes a stormwater detention pipe to achieve Flood Protection compliance. The overall 10-year Q in the post -development condition is 79.90 cfs, which is less than the 81.55 cfs in the existing condition. Summary water quantity tables and calculations are presented in Appendix D. 0 WATER QUALITY COMPLIANCE This project meets water quality compliance entirely through the purchase of nutrient credits. No BMPs are proposed to be utilized for water quality compliance. The following table summarizes the pre -development and post -development site conditions and phosphorus loading conditions. Additional water quality calculations are included in Appendix C. "A -SITE" MANAGED FORESTED ADJUSTED IMPERVIOUS Total Load Reduction SCENARIO [AREA] AREA (AC.) TURF AREA AREA P LOAD Required (Ib/yr) 0.78 (AC) (AC.) (AC.) (LB/YR) PRE- Total Load Reduction DEVELOPMENT 1.93 0.72 1.10 0.11 2.02 Provided by BMPs (lb/yr) 0.00 POST- Remaining TP Credits to be DEVELOPMENT 1.93 0.90 1.02 0.00 2.43 Purchased (lb/yr) 0.78 APPENDIX A N 716500 716700 716900 717100 38° 3' 12" N Pa i a 250 .• 0 r` O 29 O o / M ; I• p 0 rWmW WEB M N y j 4VI f11 r. a. N ti O O ti 380 2' 18" N 716500 716700 716900 717100 Map Scale: 1:8,060 i printed on B landscape (17" x 11") sheet. 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Hydrologic Soil Group -Albemarle County, Virginia, and Charlottesville City, Virginia Hydrologic Soil Group Hydrologic Soil Group- Summary by Map Unit - Albemarle County, Virginia (VA003) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 2C Albemarle fine sandy C 7.8 1.5% loam, 7 to 15 percent slopes 2D Albemarle fine sandy C 20.5 3.9% loam, 15 to 25 percent slopes 3D Albemarle very stony fine C 1.7 0.3% sandy loam, 15 to 25 percent slopes 14C Chester loam, 7 to 15 B 7.4 1.4% percent slopes 14D Chester loam, 15 to 25 B 4.3 0.8% percent slopes 19B Cullen loam, 2 to 7 B 0.4 0.1 % percent slopes 19C Cullen loam, 7 to 15 B 7.2 1.3% percent slopes 21 B Culpeper fine sandy B 44.6 8.4% loam, 2 to 7 percent slopes 21 C Culpeper fine sandy B 52.7 9.9% loam, 7 to 15 percent slopes 21 D Culpeper fine sandy B 0.4 0.1 % loam, 15 to 25 percent slopes 36B Hayesville loam, 2 to 7 B 5.8 1.1 % percent slopes 36C Hayesville loam, 7 to 15 B 13.9 2.6% percent slopes 36D Hayesville loam, 15 to 25 B 8.1 1.5% percent slopes 40D Hazel very stony loam, B 6.7 1.3% 15 to 25 percent slopes 40E Hazel very stony loam, B 25.7 4.8% 25 to 45 percent slopes 56B Meadowville loam, 2 to 7 A 4.0 0.7% percent slopes 66D Parker very stony loam, A 7.5 1.4% 15 to 25 percent slopes [jSDA Natural Resources Web Soil Survey 12/16/2015 41� Conservation Service National Cooperative Soil Survey Page 3 of 5 Hydrologic Soil Group —Albemarle County, Virginia, and Charlottesville City, Virginia Hydrologic Soil Group— Summary by Map Unit — Albemarle County, Virginia (VA003) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 66E Parker very stony loam, 25 to 45 percent slopes A 10.4 2.0% 88 Udorthents, loamy 72.8 13.7% 91 Urban land 54.2 10.2% Subtotals for Soil Survey Area 366.2 67.0% Totals for Area of Interest 631.9 100.0% Hydrologic Soil Group— Summary by Map Unit — Charlottesville City, Virginia (VA540) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 88 Udorthents, loamy 30.6 51.8 38.9 5.8% 91 Urban land 9.7% 102C Albemarle - Urban land B 7.3% complex, 7 to 15 percent slopes 102D Albemarle - Urban land B 24.1 4.5% complex, 15 to 25 percent slopes 119C Cullen - Urban land C 12.9 2.4% complex, 7 to 15 percent slopes 121 B Culpeper - Urban land C 6.1 1.2% complex, 2 to 7 percent slopes 121 C Culpeper - Urban land C 11.2 2.1 % complex, 7 to 15 percent slopes Subtotals for Soil Survey Area 176.7 33.0% Totals for Area of Interest 531.9 100.0% [jSDA Natural Resources Web Soil Survey 12/16/2015 41� Conservation Service National Cooperative Soil Survey Page 4 of 5 Hydrologic Soil Group —Albemarle County, Virginia, and Charlottesville City, Virginia Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long -duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained orwell drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink -swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff. None Specified Tie -break Rule: Higher [jSDA Natural Resources Web Soil Survey 12/16/2015 41� Conservation Service National Cooperative Soil Survey Page 5 of 5 Chapter 7 - Ditches and Channels Appendix 713-2 Recommended Maximum Water Velocities and Manning's n as a Function of Soil Type and Flow Depth Fortier and Maximum Manning's ASSHTO ASSHTO Scobey Soil Water n Classification Soil Description Description Velocity -Flow (ft/s) Depth 0.5-2.0 ft BROKEN ROCK and COBBLES Cobbles and 5.5 0.030 Shingles A-1-a Stone fragments or GRAVEL, with or Coarse without well -graded' binder gravel, non- 4.5 0.025 colloidal same same Fine gravel 3.5 0.020 Graded loam A-1-b Coarse SAND, with or without well- to cobbles 4.0 0.030 graded' binder when non- colloidal A-2 Mixture of GRAVEL and SAND, with Graded silts (A-2-4. A-2-5. silty or clay fines3, or nonplastic silt to cobbles 4.5 0.030 A-2-6, A-2-7) fines when colloidal same same Sandy loam, 2.0 0.020 non -colloidal A-3 Fine SAND, without silty clay fines; e.g. Fine Sand, beach sand or stream -deposited fine non -colloidal 1.5 0.020 sand same same Silt loam, 2.3 0.020 non -colloidal Non- to moderately plastic SILT; Alluvial silts, A-4 mixtures of silt, sand, and/or gravel, non -colloidal 2.3 0.020 with a minimum silt content of 36% A-5 Moderately to highly plastic SILT. Soil; Ordinary firm mixtures of silt, sand, and/or gravel, loam 2.5 0.020 with a minimum fines3 content of 36% A-6 Plastic CLAY soil; mixtures of clay, Alluvial silts, sand, and/or gravel, with a minimum colloidal 3.5 0.025 fines3 content of 36% A-7 Moderately to highly plastic, CLAY; Stiff clay, mixtures of clay, sand, and/or gravel, very colloidal 4.0 0.025 with a minimum clay content of 36% 1) Well -graded -containing a broad range of particle sizes with no intermediate sizes missing. 1) Binder - soil particles consisting of fine sand, silt, and clay. 2) Fines - particle sizes finer than 0.074 mm (e.g., silt and clay particles). 3) Plasticity - ability of a soil mass to deform at constant volume without cracking or crumbling. + Relationship between AASHTO classification and Fortier and Scobey description is loosely correlated. 1 of 2 VDOT Drainage Manual APPENDIX B DRAINAGE AREA MAP PRE —DEVELOPMENT 0 I 411111 V, i', - O, Pre -Development "A -Site" Land Cover OWFALL A OU FALL 6 AREA (ACRES) 0.69 123 PRE-DEV.I MP. COVER (ACRES) 0.17 ❑.54 PRE-DEV. CN 70 77 LEGEND PROJECT AREA ("A -SITE") OVERALL DRAINAGE AREA - PRE -DEVELOPMENT "A -SITE" IMPERVIOUS LAND COVER , O a O SCALE 6 260' 400' Past -Development "A -Site" Land Cover IX TFALL A OUTFALL B AREA (ACRES) ❑.69 123 POST-OEV.I MP. COVER (ACRES)E:20: 0.71 POST-OEV.CN 1 72 82 DRAINAGE AREA MAP INLET AREA [ACa 3-1 0.33 3-2 0.40 3-3 313 3-10 0.31 4-1 OS8 4-2 0.38 4-3 025 4-6 (1 5-1 024 5-2 1729 LEGEND PROJECT AREA ("A -SITE') - - - - - OVERALL DRAINAGE AREA - - - INLET AREAS - POST-DEVELOPMENT"A-SITE" IMPERVIOUS LAND COVER OFFSITE ARE STEEA ROUTED THROUGH OFFSITE DETEN 0 m J 0) Ci \�I SCALE 0 200' 400' APPENDIX C Virginia Runoff Reduction Method Worksheet DEQ Virginia Runoff Reduction Method Re -Development Compliance Spreadsheet - Version 3.0 BMP Design Specifications List: 2013 Draft Stds & Specs Site Summary - Linear Development Project*** Total Rainfall (in): 43 Total Disturbed Acreage: 1.93 Site Land Cover Summary Pre-ReDevelopment Land Cover (acresl A soils B Soils C Soils D Soils Totals %of Total Forest/Open (acres) 0.00 0.11 0.00 0.00 0.11 6 Managed Turf (acres) 0.00 1.10 0.00 0.00 1.10 57 Impervious Cover (acres) 0.00 0.72 0.00 0.00 0.72 37 1.93 100 Post-ReDevelopment Land Cover (acres) A soils B Soils C Soils D Soils Totals %of Total Forest/Open (acres) 0.00 0.00 0.00 0.00 0.00 0 Managed Turf(acres) 0.00 1.02 0.00 0.00 1.02 53 Impervious Cover (acres) 0.00 0.90 0.00 0.00 0.90 47 1A3 100 Site Tv and Land Cover Nutrient Loads Final Post -Development Past- Post- Adjusted Pre- (Post-ReDevelopment ReDevelopment Development ReDevel opment & New Impervious) p ) (New Impervious) Site Rv 0.55 0.51 0.95 0.51 Treatment Volume (ft) 3,865 3,220 645 3,220 TP Load (lb/yr) 2.43 2.02 0.41 2.02 Total TP Load Reduction Required (lb/yr) 0.78 N/A*** ***This is a linear development project Final Post -Development Load (Post-ReDevelopment & New Impervious) Pre- ReDevelopment TN Load (lb/yr) 117.37 14.77 Site Compliance Summary- ***Linear Development Project Maximum %Reduction Required Below 20% Pre-ReDevelopment Load Total Runoff Volume Reduction (it') 0 Total TP Load Reduction Achieved (Ib/yr) 0.00 Total TN Load Reduction Achieved (lb/yr) 0.00 Remaining Post Development TP Load (lb/yr) 2.43 Remaining TP Load Reduction (Ib/yr) Required 0 78 Pre- Final Post Development Post-ReDevelopment TP ReDevelopment TP Load per acre TP Load per acre (lb/acre/yr) Load per acre (lb/acre/yr) Ib/acre/ r 1.16 1.26 1.16 Summary Print Project Name Ivy Road Sidewalk Imp—ments CLEAR ALL ®_--_ ,final —� results -� Post-DevelopmentVolume __■ Enter Total Disturbed Area (acres) �— _--- BMP Design S actions List. 2013 Draft Stcls & Specs Maximum reduction required: 20%--- The site's net increase in impervious cover (acres) is: 0.186980106 Post -Development TP Load Reduction for Sire lIb/yr): 0.78 P­I�D­loprnent Land love, (acres) ■ LAND COVER SUMMARY--PRE-REDEVELOPMENT C LAND COVER SUMMARY --POST ��■�E DEVELOPMENT _ ����■ ■ ■ ��� ■ Treatment Volume and Nutrient Load Treatment Volume and Nutrient Load P 0141 Pm �® Post -Development Requirement for Site Area TP Load Reduction Required (lb/yr) Linear Project TP Load Reduction Required (lb/yr(: 0.78 APPENDIX D Stormwater Outfall Table Site Area (Acres) 1.93 Outfall A Outfall B Drainage Area From Site (Acres) 0.6950 1.2344 Overall Drainage Area (Acres) 69.08 70.81 Drainage Area to Existing Detention Systems (Acres) 9.94 3.02 Runoff Reduction (cf) 0 0 Receiving Channel Type (Natural, Restored, or Manmade) Manmade Manmade Channel Protection Compliance Method Non -Erosive Non -Erosive Flood Protection Compliance Method 10-yr QDeveloped < 10-yr QExisting 10-yr QDeveloped < 10-yr QExisting 2-year 10-year 2-year 10-year VExisting (ft/S) 15.32 N/A 14.49 N/A VDeveloped (ft/S) 15.42 N/A 14.49 N/A VAllowed (ft/S) N/A N/A N/A N/A QExisting (CFS) N/A 153.83 N/A 81.55 QDeveloped (CFS) N/A 149.61 N/A 79.90 QAllowed (CFS) N/A 153.83 N/A 81.55 NOTE: All calculations are computed using the rational method due to the site area discharging into existing manmade stormsewer systems. The calculations account for the overall drainage area reaching each outfall. Drainage areas that are assumed to drain to existing detention systems are excluded from the water quantity calculations. NOTE: Proposed detention pipes are used to reduce the 10-yr Q (cfs) in the pipes downstream of the proposed storm sewer improvements. Kimley>>Morn Storm Drain Design Calculations VDOT LD-229 Outfall A - Existing Project: Ivy Road Sidewalk Improvements Project #: 0250-002-R98 Date: 11 /30/2018 Locality: Albemarle 10 -year storm Manning n = 0.013 FROM POINT TO POINT DRAINAGE AREA RUNOFF COEFFICIENT CA INLET TIME RAINFALL RUNOFF INVERT ELEVATIONS LENGTH SLOPE SIZE PIPE CAPACITY Ct/Qr VELOCITY FLOW TIME REMARKS inlet accum upperend lowerend incr accum acres C min in/hr cfs ft ft ft % in cfs % fps min #435 #437 3.37 0.60 2.022 2.022 10.00 5.37 10.94 553.11 545.57 238 0.032 24 40.26 27% 10.90 0.36 10.00 #437 #451 3.96 0.75 2.970 4.992 10.00 5.30 45.02 543.30 538.22 273 0.019 24 30.86 146% 14.33 0.46 10.36 SURCHARGED #451 #452 0.80 0.85 0.680 5.672 9.00 5.24 60.40 537.45 536.83 92 0.007 36 54.75 110% 8.54 0.20 10.68 SURCHARGED #452 1 #452 (Out) 15.57 1 0.75 11.678 1 17.350 14.00 1 4.69 153.83 536.62 1 536.02 52 1 0.012 36 1 71.64 215% 21.76 0.04 14.00 SURCHARGED Kimley)))Horn Hydraulic Grade Line Calculations VDOT LD-347 Outfall A - Existing Project: Ivy Road Sidewalk Improvements Project M 0250-002-R98 Date: 11 /30/2018 Locality: Albemarle 10 -year storm Angle 0 15 20 25 30 40 50 60 70 80 90 K 0 0.19 0.25 0.30 0.35 0.43 0.50 0.56 0.61 0.66 0.70 INLET O.SD+ INV (OUT) ACTUAL OUTLET WSE DESIGN OUTLET WSE Do Qo Lo Sfo H JUNCTION LOSS FINAL H INLET WSE F/L ELEV Vo (8) Ho (9) Q; (10) V; (11) Q;V; (12) V,. Zg H; Angle Ho Ht Surface Runoff Factor? 1.3 Ht IS-1? 0.5 H, (1) (2) (3) (4) (5) (6) (7) (13) (14) (15) (16) (17) (18) (19) (20) (21) #452 538.42 538.42 538.42 36 153.83 52 0.0532 2.77 21.76 1.84 60.40 8.54 515.82 1.13 0.40 60 0.63 2.87 YES 3.73 YES 1.86 4.63 � 542.68 #451 539.23 543.05 543.05 36 60.40 92 0.0082 0.75 8.54 0.28 45.02 14.33 645.14 3.19 1.12 0 0.00 1.40 YES 1.82 YES 0.91 1.66 544.72 546.25 #437 539.82 544.72 544.72 24 45.02 273 0.0396 10.82 14.33 0.80 10.94 10.90 119.25 1.84 0.65 15 0.35 1.79 YES 2.33 YES 1.17 11.98 . 1 551.55 #435 547.17 556.70 556.70 24 10.94 238 0.0023 0.56 10.90 0.46 0.00 0.00 0.00 0.00 0.00 0 0.00 0.46 YES 0.60 YES 0.30 0.86 557.55 558.22 Kimley>>Morn Storm Drain Design Calculations VDOT LD-229 Outfall B - Existing Project: Ivy Road Sidewalk Improvements Project #: 0250-002-R98 Date: 8/22/2017 Locality: Albemarle 10 -year storm Manning n = 0.013 FROM POINT TO POINT DRAINAGE AREA RUNOFF COEFFICIENT CA INLETTIME RAINFALL RUNOFF INVERT ELEVATIONS LENGTH SLOPE SIZE PIPE CAPACITY Q/Qf VELOCITY FLOW TIME REMARKS inlet accum upper end lower end incr I accum acres C min in/hr cfs ft ft ft % in cfs % fps min #431 #432 1.94 0.75 1.455 1.455 5.00 6.67 9.78 556.78 553.43 112 0.03 15 11.17 88% 10.26 0.18 5.00 #432 #432-A 0.34 0.85 0.289 1.744 5.00 6.61 11.61 553.43 551.00 84 0.029 15 10.99 106% 10.12 0.14 5.18 SURCHARGED #432-A #418-A (N/A) (N/A) 0.000 1.744 0.00 6.56 11.53 550.00 545.70 180 0.024 24 34.96 33% 9.98 0.30 5.32 #418-A #418 0.31 0.70 0.217 1.961 5.00 6.47 12.78 544.70 1 544.43 12 1 0.023 24 1 33.93 38% 1 10.04 0.02 5.62 #418 #415 0.38 0.75 0.285 2.246 5.00 6.46 14.62 542.03 541.34 53 0.013 24 25.81 57% 8.47 0.10 5.64 #415 #400 0.38 0.75 0.285 2.531 5.00 6.43 16.39 541.32 538.37 131 0.023 24 33.95 48% 10.71 0.20 5.75 #400 #401 0.46 0.75 0.345 2.876 5.00 6.36 18.45 538.30 536.77 61 0.025 24 35.83 51% 5.87 0.17 1 5.95 #401 #421-A 0.93 0.80 0.744 3.620 5.00 6.31 23.03 536.70 535.93 98 0.008 24 20.05 115% 7.33 0.22 6.12 SURCHARGED #421-A #405 (N/A) (N/A) 0.000 3.620 0.00 6.25 22.80 535.93 535.56 47 0.008 24 20.07 114% 7.26 0.11 6.35 SURCHARGED #405 #406 0.03 0.55 0.017 3.636 5.00 6.22 22.79 535.52 535.33 24 0.008 24 20.13 113% 7.25 0.06 6.45 ISURCHARGED #406 #409 23.17 0.60 13.902 17.538 15.13 4.53 80.04 535.05 529.23 185 1 0.031 24 40.12 200% 25.48 0.12 15.13 SURCHARGED #409 #409 (Out) 0.79 0.50 0.395 17.934 5.00 4.51 81.55 528.19 526.50 73 0.023 30 62.41 131% 16.61 0.07 15.25 SURCHARGED Kimley)))Horn Hydraulic Grade Line Calculations VDOT LD-347 Outfall B - Existing Project: Ivy Road Sidewalk Improvements Project M 0250-002-R98 Date: 8/22/2017 Locality: Albemarle 10 -year storm Angle 0 15 20 25 30 40 50 60 70 80 90 K 0 0.19 0.25 0.30 0.35 0.43 0.50 0.56 0.61 0.66 0.70 INLET 0.8D+ INV (OUT) ACTUAL OUTLET WSE DESIGN OUTLET WSE Do Qo L. Sfo Ht JUNCTION LOSS FINALH INLET F/L WSE ELEV Vo (8) Ho (9) Q (10) V; (11) Q;V; (12) z V,. Zg H; Angle Ho H, Surface Runoff Factor? 1.3 H, IS-17 0.5 H, (1) (2) (3) (4) (5) (6) (7) (13) (14) (15) (16) (17) (18) (19) (20) (21) #409 528.50 529.00 529.00 30 81.55 73 0.0395 2.89 16.61 1.07 80.04 25.48 2039.42 10.08 3.53 40 4.33 8.93 NO 8.93 YES 4.47 7.35 534.80 #406 530.83 536.35 536.35 24 80.04 185 0.1252 23.17 25.48 2.52 22.79 7.25 165.23 0.82 0.29 90 0.57 3.38 YES 4.39 YES 2.20 25.36 538.07 #405 536.93 561.71 561.71 24 22.79 24 0.0102 0.24 7.25 0.20 22.80 7.26 165.53 0.82 0.29 90 0.57 1.06 NO 1.06 YES 0.53 0.78 538.36 #421-A 537.16 562.49 562.49 24 22.80 47 0.0102 0.48 7.26 0.20 23.03 7.33 168.81 0.83 0.29 0 0.00 0.50 NO 0.50 YES 0.25 0.73 542.23 #401 537.53 563.22 563.22 24 23.03 98 0.0104 1.02 7.33 0.21 18.45 5.87 108.30 0.54 0.19 15 0.10 0.50 YES 0.65 YES 0.32 1.34 541.39 #400 538.37 564.56 564.56 24 18.45 61 0.0067 0.41 5.87 0.13 16.39 10.71 175.54 1.78 0.62 0 0.00 0.76 YES 0.98 YES 0.49 0.90 543.33 #415 539.97 565.45 565.45 24 16.39 131 0.0053 0.69 10.71 0.45 14.62 8.47 123.83 1.11 0.39 0 0.00 0.84 YES 1.09 YES 0.54 1.23 547.38 #418 542.94 566.68 566.68 24 14.62 53 0.0042 0.22 8.47 0.28 12.78 10.04 128.31 1.57 0.55 0 0.00 0.83 YES 1.07 YES 0.54 0.76 548.56 #418-A 546.03 567.44 567.44 24 12.78 12 0.0032 0.04 10.04 0.39 11.53 9.98 115.07 1.55 0.54 0 0.00 0.93 YES 1.21 YES 0.61 0.64 .: r • 549.94 #432-A 547.30 568.09 568.09 24 11.53 180 0.0026 0.47 1 9.98 0.39 11.61 10.12 117.49 1.59 0.56 15 0.30 1.25 NO 1.25 YES 0.62 1.09 558.28 #432 552.00 569.18 569.18 15 11.61 84 0.0323 2.71 10.12 0.40 9.78 10.26 100.34 1.63 0.57 15 0.31 1.28 YES 1.66 YES 0.83 3.55 556.85 #431 554.43 572.72 572.72 15 9.78 112 0.0229 2.57 10.26 0.41 0.00 0.00 0.00 0.00 0.00 0 0.00 0.41 YES 0.53 YES 0.27 2.83 561.17 APPENDIX E 1S---�> z 2P Incoming Area to Detention System A Detention System A Subcat Reach on Link Detention System A Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area C Description (acres) (subcatchment-numbers) 0.727 0.75 (1S) 1.128 0.85 (is) 1.855 0.81 TOTAL AREA Detention System A Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 3 Pipe Listing (all nodes) Line# Node In -Invert Out -Invert Length Slope n Diam/Width Height Inside -Fill Number (feet) (feet) (feet) (ft/ft) (inches) (inches) (inches) 1 2P 554.50 554.45 10.0 0.0050 0.013 24.0 0.0 0.0 Detention System A VA -Albemarle 2-Year Duration=9 min, Inten=4.29 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 4 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1.0/1.0 xTc Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: IncomingAreato Runoff Area=1.855 ac 0.00% Impervious Runoff Depth=0.52" Tc=6.0 min C=0.81 Runoff=6.50 cfs 0.081 of Pond 2P: Detention System A Peak Elev=556.76' Storage=0.021 of Inflow=6.50 cfs 0.081 of Outflow=5.88 cfs 0.073 of Total Runoff Area = 1.855 ac Runoff Volume = 0.081 of Average Runoff Depth = 0.52" 100.00% Pervious = 1.855 ac 0.00% Impervious = 0.000 ac Detention System A VA -Albemarle 2-Year Duration=9 min, Inten=4.29 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 5 Summary for Subcatchment 1S: Incoming Area to Detention System A Runoff = 6.50 cfs @ 0.10 hrs, Volume= 0.081 af, Depth= 0.52" Runoff by Rational method, Rise/Fall=1.0/1.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs VA -Albemarle 2-Year Duration=9 min, Inten=4.29 in/hr Area (ac) C Description 0.325 0.75 0.402 0.75 1.128 0.85 1.855 0.81 Weighted Average 1.855 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Incoming Area to Detention System A Hydrograph 74 L I I ❑Runoff VA -Albemarle 2-Year 6 Duration=9 min, 5 Inten=4.29 in/hr Runoff Area=1.855 ac 4 Runoff Volume=0.081 of LL 3 - - - - - - - - Runoff Depth=0.52" Tc=6.0 m i n 2 C=0.81 1 0 0 1 2 3 Time (hours) Detention System A VA -Albemarle 2-Year Duration=9 min, Inten=4.29 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 6 Summary for Pond 2P: Detention System A Inflow Area = 1.855 ac, 0.00% Impervious, Inflow Depth = 0.52" for 2-Year event Inflow = 6.50 cfs @ 0.10 hrs, Volume= 0.081 of Outflow = 5.88 cfs @ 0.16 hrs, Volume= 0.073 af, Atten= 10%, Lag= 3.6 min Primary = 5.88 cfs @ 0.16 hrs, Volume= 0.073 of Routing by Stor-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 556.76' @ 0.16 hrs Surf.Area= 0.010 ac Storage= 0.021 of Plug -Flow detention time= 2.4 min calculated for 0.073 of (90% of inflow) Center -of -Mass det. time= 1.9 min ( 9.4 - 7.5 ) Volume Invert Avail.Storage Storage Description #1 554.50' 0.039 of 72.0" W x 48.0" H Box Pipe Storage L= 70.0' S= 0.0030 T Device Routing Invert Outlet Devices #1 Primary 554.50' 24.0" Round Culvert L= 10.0' RCP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 554.50' / 554.45' S= 0.0050 T Cc= 0.900 n= 0.013, Flow Area= 3.14 sf #2 Device 1 557.70' 7.0' long x 0.7' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 Coef. (English) 2.76 2.82 2.93 3.09 3.18 3.22 3.27 3.30 3.32 3.31 3.32 #3 Device 1 554.50' 14.0" Vert. Orifice/Grate C= 0.600 Primary OutFlow Max=5.88 cfs @ 0.16 hrs HW=556.76' TW=555.45' (Fixed TW Elev= 555.45') L1=Culvert (Passes 5.88 cfs of 14.11 cfs potential flow) 17- 2=Broad-Crested Rectangular Weir( Controls 0.00 cfs) 3=Orifice/Grate (Orifice Controls 5.88 cfs @ 5.50 fps) Detention System A VA -Albemarle 2-Year Duration=9 min, Inten=4.29 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCADO 10.00-22 s/n 09843 © 2018 HydroCAD Software Solutions LLC Page 7 V! G Pond 2P: Detention System A Hydrograph Time (hours) ■ Inflow ❑ Primary Detention System A VA -Albemarle 10-Year Duration=9 min, Inten=5.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 1 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1.0/1.0 xTc Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: IncomingAreato Runoff Area=1.855 ac 0.00% Impervious Runoff Depth=0.68" Tc=6.0 min C=0.81 Runoff=8.45 cfs 0.105 of Pond 2P: Detention System A Peak Elev=557.49' Storage=0.028 of Inflow=8.45 cfs 0.105 of Outflow=7.36 cfs 0.097 of Total Runoff Area = 1.855 ac Runoff Volume = 0.105 of Average Runoff Depth = 0.68" 100.00% Pervious = 1.855 ac 0.00% Impervious = 0.000 ac Detention System A VA -Albemarle 10-Year Duration=9 min, Inten=5.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 1S: Incoming Area to Detention System A Runoff = 8.45 cfs @ 0.10 hrs, Volume= 0.105 af, Depth= 0.68" Runoff by Rational method, Rise/Fall=1.0/1.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs VA -Albemarle 10-Year Duration=9 min, Inten=5.58 in/hr Area (ac) C Description 0.325 0.75 0.402 0.75 1.128 0.85 1.855 0.81 Weighted Average 1.855 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Incoming Area to Detention System A Hydrograph ❑ Runoff 8 VA -Albemarle 10-Year ---------- Duration=9min, Inten=5.58 in/hr 6 Runoff Area=1.855 ac 5 - Runoff Volume=0.105 of .2 4 Runoff Depth=0.68" -- -- - --- Tc=6.0min 3 C=0.81 2 1 0 0 1 2 3 Time (hours) Detention System A VA -Albemarle 10-Year Duration=9 min, Inten=5.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 3 Summary for Pond 2P: Detention System A Inflow Area = 1.855 ac, 0.00% Impervious, Inflow Depth = 0.68" for 10-Year event Inflow = 8.45 cfs @ 0.10 hrs, Volume= 0.105 of Outflow = 7.36 cfs @ 0.16 hrs, Volume= 0.097 af, Atten= 13%, Lag= 3.8 min Primary = 7.36 cfs @ 0.16 hrs, Volume= 0.097 of Routing by Stor-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 557.49' @ 0.16 hrs Surf.Area= 0.010 ac Storage= 0.028 of Plug -Flow detention time= 2.5 min calculated for 0.096 of (92% of inflow) Center -of -Mass det. time= 2.0 min ( 9.5 - 7.5 ) Volume Invert Avail.Storage Storage Description #1 554.50' 0.039 of 72.0" W x 48.0" H Box Pipe Storage L= 70.0' S= 0.0030 T Device Routing Invert Outlet Devices #1 Primary 554.50' 24.0" Round Culvert L= 10.0' RCP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 554.50' / 554.45' S= 0.0050 7' Cc= 0.900 n= 0.013, Flow Area= 3.14 sf #2 Device 1 557.70' 7.0' long x 0.7' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 Coef. (English) 2.76 2.82 2.93 3.09 3.18 3.22 3.27 3.30 3.32 3.31 3.32 #3 Device 1 554.50' 14.0" Vert. Orifice/Grate C= 0.600 Primary OutFlow Max=7.34 cfs @ 0.16 hrs HW=557.48' TW=555.45' (Fixed TW Elev= 555.45') L1=Culvert (Passes 7.34 cfs of 20.11 cfs potential flow) 17- 2=Broad-Crested Rectangular Weir( Controls 0.00 cfs) 3=Orifice/Grate (Orifice Controls 7.34 cfs @ 6.87 fps) Detention System A VA -Albemarle 10-Year Duration=9 min, Inten=5.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCADO 10.00-22 s/n 09843 © 2018 HydroCAD Software Solutions LLC Page 4 N w V Pond 2P: Detention System A Hydrograph Time (hours) ■ Inflow ❑ Primary Detention System A VA -Albemarle 100-Year Duration=8 min, Inten=7.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 1 Time span=0.00-3.00 hrs, dt=0.01 hrs, 301 points Runoff by Rational method, Rise/Fall=1.0/1.0 xTc Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment1S: IncomingAreato Runoff Area=1.855 ac 0.00% Impervious Runoff Depth=0.82" Tc=6.0 min C=0.81 Runoff=11.49 cfs 0.127 all Pond 2P: Detention System A Peak Elev=557.99' Storage=0.033 of Inflow=11.49 cfs 0.127 of Outflow=11.32 cfs 0.119 of Total Runoff Area = 1.855 ac Runoff Volume = 0.127 of Average Runoff Depth = 0.82" 100.00% Pervious = 1.855 ac 0.00% Impervious = 0.000 ac Detention System A VA -Albemarle 100-Year Duration=8 min, Inten=7.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCADO 10.00-22 s/n 09843 © 2018 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 1S: Incoming Area to Detention System A Runoff = 11.49 cfs @ 0.10 hrs, Volume= 0.127 af, Depth= 0.82" Runoff by Rational method, Rise/Fall=1.0/1.0 xTc, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs VA -Albemarle 100-Year Duration=8 min, Inten=7.58 in/hr Area (ac) C Description 0.325 0.75 0.402 0.75 1.128 0.85 1.855 0.81 Weighted Average 1.855 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Incoming Area to Detention System A Hydrograph 12 11 4-9 11 VA -Albemarle 100-Year 10 Duration=8 min, 9 Inten=7.58 in/hr 8 Runoff Area=1.855 ac - - - Runoff'Volume=0.127 of LL 6 _ _ _ _ _ Runoff Depth=0.82" 5 Tc=6.0 m i n 4 C=0.81 1 0 1 Time (hours) 2 3 ■ Runoff Detention System A VA -Albemarle 100-Year Duration=8 min, Inten=7.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCAD® 10.00-22 s/n 09843 ©2018 HydroCAD Software Solutions LLC Page 3 Summary for Pond 2P: Detention System A Inflow Area = 1.855 ac, 0.00% Impervious, Inflow Depth = 0.82" for 100-Year event Inflow = 11.49 cfs @ 0.10 hrs, Volume= 0.127 of Outflow = 11.32 cfs @ 0.13 hrs, Volume= 0.119 af, Atten= 2%, Lag= 2.1 min Primary = 11.32 cfs @ 0.13 hrs, Volume= 0.119 of Routing by Stor-Ind method, Time Span= 0.00-3.00 hrs, dt= 0.01 hrs Peak Elev= 557.99' @ 0.13 hrs Surf.Area= 0.010 ac Storage= 0.033 of Plug -Flow detention time= 2.4 min calculated for 0.118 of (93% of inflow) Center -of -Mass det. time= 2.0 min ( 9.0 - 7.0 ) Volume Invert Avail.Storage Storage Description #1 554.50' 0.039 of 72.0" W x 48.0" H Box Pipe Storage L= 70.0' S= 0.0030 T Device Routing Invert Outlet Devices #1 Primary 554.50' 24.0" Round Culvert L= 10.0' RCP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 554.50' / 554.45' S= 0.0050 7' Cc= 0.900 n= 0.013, Flow Area= 3.14 sf #2 Device 1 557.70' 7.0' long x 0.7' breadth Broad -Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 Coef. (English) 2.76 2.82 2.93 3.09 3.18 3.22 3.27 3.30 3.32 3.31 3.32 #3 Device 1 554.50' 14.0" Vert. Orifice/Grate C= 0.600 Primary OutFlow Max=11.12 cfs @ 0.13 hrs HW=557.98' TW=555.45' (Fixed TW Elev= 555.45') L1=Culvert (Passes 11.12 cfs of 23.83 cfs potential flow) 17- 2=Broad-Crested Rectangular Weir(Weir Controls 2.93 cfs @ 1.48 fps) 3=Orifice/Grate (Orifice Controls 8.19 cfs @ 7.66 fps) Detention System A VA -Albemarle 100-Year Duration=8 min, Inten=7.58 in/hr Prepared by Kimley-Horn and Associates Printed 11/30/2018 HydroCADO 10.00-22 s/n 09843 © 2018 HydroCAD Software Solutions LLC Page 4 Pond 2P: Detention System A Hydrograph ■ Inflow ❑ Primary Time (hours) Hydraflow Table of Contents Ivy Detention Pipes-Rational.gpw Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Friday, 11 / 30 / 2018 Watershed Model Schematic...................................................................................... 1 Hydrograph Return Period Recap............................................................................. 2 2 - Year SummaryReport......................................................................................................................... 3 HydrographReports................................................................................................................... 4 Hydrograph No. 1, Rational, Area to Outfall B Detention......................................................... 4 Hydrograph No. 2, Reservoir, Detention Pipe B....................................................................... 5 Pond Report - Outfall B Detention Pipe............................................................................... 6 10 -Year SummaryReport......................................................................................................................... 8 HydrographReports................................................................................................................... 9 Hydrograph No. 1, Rational, Area to Outfall B Detention......................................................... 9 Hydrograph No. 2, Reservoir, Detention Pipe B..................................................................... 10 100 - Year SummaryReport....................................................................................................................... 11 HydrographReports................................................................................................................. 12 Hydrograph No. 1, Rational, Area to Outfall B Detention....................................................... 12 Hydrograph No. 2, Reservoir, Detention Pipe B..................................................................... 13 OFReport.................................................................................................................. 14 Watershed Model Schematic HydraflowHydrographsExtension for Autodesk® Civil 3D®2019byAutodesk,Inc. v202O Legend Hvd. Origin Description 1 Rational Area to Outfall B Detention 2 Reservoir Detention Pipe B Project: Ivy Detention Pipes-Rational.gpw Friday, 11 / 30 / 2018 Hydrograph Return Period Re,cd4 ew Hydrographs Extension for Autodesk®Civil 3D® 2019 by Autodesk, Inc. v2020 Hyd. No. Hydrograph type (origin) Inflow hyd(s) Peak Outflow (cfs) Hydrograph Description 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr 1 2 Rational Reservoir ------ 1 ------- ------- 9.937 6.045 ------- ------- ------- ------- 12.79 7.265 ------- ------- ------- ------- 16.81 12.01 Area to Outfall B Detention Detention Pipe B Proj. file: Ivy Detention Pipes-Rational.gpw Friday, 11 / 30 / 2018 Hydrograph Summary ReportH ydraflow Hydrographs Extension for Autodesk®Civil 3D® 2019 by Autodesk, Inc. v2020 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cuft) Inflow hyd(s) Maximum elevation (ft) Total strge used (cuft) Hydrograph Description 1 Rational 9.937 1 5 2,981 ------ ------ ------ Area to Outfall B Detention 2 Reservoir 6.045 1 7 2,737 1 546.99 1,192 Detention Pipe B Ivy Detention Pipes-Rational.gpw Return Period: 2 Year Friday, 11 / 30 / 2018 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Friday, 11 / 30 / 2018 Hyd. No. 1 Area to Outfall B Detention Hydrograph type = Rational Peak discharge = 9.937 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 2,981 cuft Drainage area = 2.558 ac Runoff coeff. = 0.75 Intensity = 5.180 in/hr Tc by User = 5.00 min OF Curve = Ivy.IDF Asc/Rec limb fact = 1/1 Q (cfs) 10.00 . 11 4.00 2.00 Area to Outfall B Detention Hyd. No. 1 -- 2 Year Q (cfs) 10.00 . 11 4.00 2.00 0.00 It ' ' ' ' ' ' ' ' ' N 0.00 0 1 2 3 4 5 6 7 8 9 10 Hyd No. 1 Time (min) Hydrograph Report 5 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Hyd. No. 2 Detention Pipe B Hydrograph type = Reservoir Peak discharge Storm frequency = 2 yrs Time to peak Time interval = 1 min Hyd. volume Inflow hyd. No. = 1 - Area to Outfall B Detention Max. Elevation Reservoir name = Outfall B Detention Pipe Max. Storage Storage Indication method used. Q (cfs) 10.00 . 11 4.00 2.00 0.00 W ' 0 1 2 Hyd No. 2 3 4 5 Hyd No. 1 Detention Pipe B Hyd. No. 2 -- 2 Year Friday, 11 / 30 / 2018 = 6.045 cfs = 7 min = 2,737 cuft = 546.99 ft = 1,192 cuft Q (cfs) 10.00 . 11 4.00 2.00 0.00 7 8 9 10 11 12 13 14 Time (min) I_I_I_I_I_I_I Total storage used = 1,192 cuft Pond Report a Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Friday, 11 / 30 / 2018 Pond No. 2 - Outfall B Detention Pipe Pond Data UG Chambers -Invert elev. = 544.70 ft, Rise x Span = 4.00 x 4.00 ft, Barrel Len = 191.30 ft, No. Barrels = 1, Slope = 0.31 %, Headers = No Stage / Storage Table Stage (ft) Elevation (ft) Contour area (scift) Incr. Storage (cuft) Total storage (cuft) 0.00 544.70 n/a 0 0 0.46 545.16 n/a 48 48 0.92 545.62 n/a 196 244 1.38 546.08 n/a 284 528 1.84 546.54 n/a 327 856 2.30 547.00 n/a 347 1,202 2.76 547.46 n/a 347 1,550 3.22 547.92 n/a 327 1,877 3.67 548.37 n/a 284 2,161 4.13 548.83 n/a 196 2,357 4.59 549.29 n/a 48 2,404 Culvert / Orifice Structures [A] [B] [C] [PrfRsr] Rise (in) = 24.00 15.00 Inactive Inactive Span (in) = 24.00 15.00 0.00 0.00 No. Barrels = 1 1 1 0 Invert El. (ft) = 544.60 544.60 0.00 0.00 Length (ft) = 24.00 0.00 0.00 0.00 Slope (%) = 1.27 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Multi -Stage = n/a Yes No No Weir Structures [A] [B] [C] [D] Crest Len (ft) = 20.00 6.17 Inactive Inactive Crest El. (ft) = 549.29 547.60 0.00 0.00 Weir Coeff. = 3.33 3.33 3.33 3.33 Weir Type = 1 Rect --- --- Multi-Stage = Yes Yes No No Exfil.(in/hr) = 0.000 (by Contour) TW Elev. (ft) = 545.62 Note: Culvert/Orifice outflows are analyzed under inlet (ic) and outlet (oc) control. Weir risers checked for orifice conditions (ic) and submergence (s). Stage / Storage / Discharge Table Stage Storage Elevation CIv 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 0 544.70 0.00 0.00 --- --- 0.00 0.00 --- --- 0.05 5 544.75 0.00 0.00 --- --- 0.00 0.00 --- --- 0.09 10 544.79 0.00 0.00 --- --- 0.00 0.00 --- --- 0.14 14 544.84 0.00 0.00 --- --- 0.00 0.00 --- --- 0.18 19 544.88 0.00 0.00 --- --- 0.00 0.00 --- --- 0.23 24 544.93 0.00 0.00 --- --- 0.00 0.00 --- --- 0.28 29 544.98 0.00 0.00 --- --- 0.00 0.00 --- --- 0.32 33 545.02 0.00 0.00 --- --- 0.00 0.00 --- --- 0.37 38 545.07 0.00 0.00 --- --- 0.00 0.00 --- --- 0.41 43 545.11 0.00 0.00 --- --- 0.00 0.00 --- --- 0.46 48 545.16 0.00 0.00 --- --- 0.00 0.00 --- --- 0.51 67 545.21 0.00 0.00 --- --- 0.00 0.00 --- --- 0.55 87 545.25 0.00 0.00 --- --- 0.00 0.00 --- --- 0.60 107 545.30 0.00 0.00 --- --- 0.00 0.00 --- --- 0.64 126 545.34 0.00 0.00 --- --- 0.00 0.00 --- --- 0.69 146 545.39 0.00 0.00 --- --- 0.00 0.00 --- --- 0.73 165 545.44 0.00 0.00 --- --- 0.00 0.00 --- --- 0.78 185 545.48 0.00 0.00 --- --- 0.00 0.00 --- --- 0.83 205 545.53 0.00 0.00 --- --- 0.00 0.00 --- --- 0.87 224 545.57 0.00 0.00 --- --- 0.00 0.00 --- --- 0.92 244 545.62 0.00 0.00 --- --- 0.00 0.00 --- --- 0.96 272 545.66 0.95 is 0.94 is --- --- 0.00 0.00 --- --- 1.01 301 545.71 1.38 is 1.38 is --- --- 0.00 0.00 --- --- 1.06 329 545.76 1.74 is 1.74 is --- --- 0.00 0.00 --- --- 1.10 358 545.80 2.06 is 2.05 is --- --- 0.00 0.00 --- --- 1.15 386 545.85 2.35 is 2.32 is --- --- 0.00 0.00 --- --- 1.19 414 545.89 2.55 is 2.55 is --- --- 0.00 0.00 --- --- 1.24 443 545.94 2.77 is 2.77 is --- --- 0.00 0.00 --- --- 1.29 471 545.99 2.98 is 2.98 is --- --- 0.00 0.00 --- --- 1.33 500 546.03 3.18 is 3.18 is --- --- 0.00 0.00 --- --- 1.38 528 546.08 3.40 is 3.35 is --- --- 0.00 0.00 --- --- 1.42 561 546.12 3.53 is 3.53 is --- --- 0.00 0.00 --- --- --- 0.000 --- 0.000 --- 0.000 --- 0.000 0.000 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.000 --- --- 0.941 --- --- 1.381 --- --- 1.739 --- --- 2.053 --- --- 2.321 --- --- 2.552 --- --- 2.773 --- --- 2.980 --- --- 3.178 --- --- 3.350 --- --- 3.530 Continues on next page... 7 Outfall B Detention Pipe 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 1.47 594 546.17 3.71 is 3.70 is --- --- 0.00 0.00 --- --- --- --- 3.704 1.52 626 546.22 3.89 is 3.87 is --- --- 0.00 0.00 --- --- --- --- 3.867 1.56 659 546.26 4.02 is 4.02 is --- --- 0.00 0.00 --- --- --- --- 4.019 1.61 692 546.31 4.18 is 4.18 is --- --- 0.00 0.00 --- --- --- --- 4.178 1.65 725 546.35 4.36 is 4.32 is --- --- 0.00 0.00 --- --- --- --- 4.324 1.70 757 546.40 4.47 is 4.47 is --- --- 0.00 0.00 --- --- --- --- 4.466 1.75 790 546.45 4.61 is 4.61 is --- --- 0.00 0.00 --- --- --- --- 4.614 1.79 823 546.49 4.74 is 4.74 is --- --- 0.00 0.00 --- --- --- --- 4.740 1.84 856 546.54 4.88 is 4.88 is --- --- 0.00 0.00 --- --- --- --- 4.881 1.88 890 546.58 5.04 is 5.01 is --- --- 0.00 0.00 --- --- --- --- 5.011 1.93 925 546.63 5.14 is 5.14 is --- --- 0.00 0.00 --- --- --- --- 5.138 1.98 960 546.68 5.27 is 5.27 is --- --- 0.00 0.00 --- --- --- --- 5.271 2.02 994 546.72 5.38 is 5.38 is --- --- 0.00 0.00 --- --- --- --- 5.384 2.07 1,029 546.77 5.51 is 5.51 is --- --- 0.00 0.00 --- --- --- --- 5.513 2.11 1,064 546.81 5.62 is 5.62 is --- --- 0.00 0.00 --- --- --- --- 5.622 2.16 1,098 546.86 5.75 is 5.75 is --- --- 0.00 0.00 --- --- --- --- 5.748 2.20 1,133 546.90 5.85 is 5.85 is --- --- 0.00 0.00 --- --- --- --- 5.853 2.25 1,168 546.95 5.97 is 5.97 is --- --- 0.00 0.00 --- --- --- --- 5.975 2.30 1,202 547.00 6.15 is 6.08 is --- --- 0.00 0.00 --- --- --- --- 6.076 2.34 1,237 547.04 6.19 is 6.19 is --- --- 0.00 0.00 --- --- --- --- 6.194 2.39 1,272 547.09 6.37 is 6.29 is --- --- 0.00 0.00 --- --- --- --- 6.294 2.43 1,307 547.13 6.41 is 6.41 is --- --- 0.00 0.00 --- --- --- --- 6.409 2.48 1,341 547.18 6.58 is 6.50 is --- --- 0.00 0.00 --- --- --- --- 6.505 2.53 1,376 547.23 6.62 is 6.62 is --- --- 0.00 0.00 --- --- --- --- 6.617 2.57 1,411 547.27 6.71 is 6.71 is --- --- 0.00 0.00 --- --- --- --- 6.711 2.62 1,446 547.32 6.82 is 6.82 is --- --- 0.00 0.00 --- --- --- --- 6.821 2.66 1,480 547.36 6.91 is 6.91 is --- --- 0.00 0.00 --- --- --- --- 6.913 2.71 1,515 547.41 7.02 is 7.02 is --- --- 0.00 0.00 --- --- --- --- 7.020 2.76 1,550 547.46 7.11 is 7.11 is --- --- 0.00 0.00 --- --- --- --- 7.109 2.80 1,583 547.50 7.22 is 7.21 is --- --- 0.00 0.00 --- --- --- --- 7.212 2.85 1,615 547.55 7.30 is 7.30 is --- --- 0.00 0.00 --- --- --- --- 7.301 2.89 1,648 547.59 7.43 is 7.40 is --- --- 0.00 0.00 --- --- --- --- 7.398 2.94 1,681 547.64 7.64 is 7.47 is --- --- 0.00 0.16 --- --- --- --- 7.635 2.99 1,714 547.69 8.04 is 7.51 is --- --- 0.00 0.51 --- --- --- --- 8.029 3.03 1,746 547.73 8.52 is 7.54 is --- --- 0.00 0.98 --- --- --- --- 8.518 3.08 1,779 547.78 9.01 oc 7.48 is --- --- 0.00 1.54 --- --- --- --- 9.015 3.12 1,812 547.82 9.52 oc 7.35 is --- --- 0.00 2.17 --- --- --- --- 9.516 3.17 1,844 547.87 10.05 oc 7.16 is --- --- 0.00 2.87 --- --- --- --- 10.04 3.22 1,877 547.92 10.41 oc 6.77 is --- --- 0.00 3.64 --- --- --- --- 10.41 3.26 1,906 547.96 11.22 oc 6.76 is --- --- 0.00 4.46 --- --- --- --- 11.22 3.31 1,934 548.01 12.07 oc 6.74 is --- --- 0.00 5.34 --- --- --- --- 12.07 3.35 1,962 548.05 12.96 oc 6.69 is --- --- 0.00 6.27 --- --- --- --- 12.96 3.40 1,991 548.10 13.87 oc 6.63 is --- --- 0.00 7.24 --- --- --- --- 13.87 3.44 2,019 548.15 14.82 oc 6.55 is --- --- 0.00 8.27 --- --- --- --- 14.82 3.49 2,047 548.19 15.78 oc 6.45 is --- --- 0.00 9.33 --- --- --- --- 15.78 3.54 2,076 548.24 16.77 oc 6.33 is --- --- 0.00 10.44 --- --- --- --- 16.77 3.58 2,104 548.28 17.78 oc 6.18 is --- --- 0.00 11.59 --- --- --- --- 17.78 3.63 2,132 548.33 18.80 oc 6.01 is --- --- 0.00 12.78 --- --- --- --- 18.80 3.67 2,161 548.37 19.82 oc 5.82 is --- --- 0.00 14.00 --- --- --- --- 19.82 3.72 2,180 548.42 20.86 oc 5.59 is --- --- 0.00 15.27 --- --- --- --- 20.86 3.77 2,200 548.47 21.67 is 5.26 is --- --- 0.00 16.41 s --- --- --- --- 21.67 3.81 2,220 548.51 22.27 is 5.03 is --- --- 0.00 17.24 s --- --- --- --- 22.27 3.86 2,239 548.56 22.79 is 4.83 is --- --- 0.00 17.96 s --- --- --- --- 22.79 3.90 2,259 548.60 23.27 is 4.64 is --- --- 0.00 18.62 s --- --- --- --- 23.26 3.95 2,278 548.65 23.70 is 4.48 is --- --- 0.00 19.22 s --- --- --- --- 23.70 4.00 2,298 548.70 24.11 is 4.32 is --- --- 0.00 19.79 s --- --- --- --- 24.11 4.04 2,318 548.74 24.49 is 4.18 is --- --- 0.00 20.31 s --- --- --- --- 24.49 4.09 2,337 548.79 24.85 is 4.04 is --- --- 0.00 20.81 s --- --- --- --- 24.85 4.13 2,357 548.83 25.19 is 3.92 is --- --- 0.00 21.28 s --- --- --- --- 25.19 4.18 2,362 548.88 25.52 is 3.79 is --- --- 0.00 21.73 s --- --- --- --- 25.52 4.23 2,366 548.93 25.83 is 3.68 is --- --- 0.00 22.15 s --- --- --- --- 25.83 4.27 2,371 548.97 26.13 is 3.57 is --- --- 0.00 22.56 s --- --- --- --- 26.13 4.32 2,376 549.02 26.42 is 3.47 is --- --- 0.00 22.95 s --- --- --- --- 26.42 4.36 2,381 549.06 26.70 is 3.38 is --- --- 0.00 23.32 s --- --- --- --- 26.70 4.41 2,385 549.11 26.97 is 3.28 is --- --- 0.00 23.69 s --- --- --- --- 26.97 4.46 2,390 549.16 27.23 is 3.20 is --- --- 0.00 24.04 s --- --- --- --- 27.23 4.50 2,395 549.20 27.49 is 3.12 is --- --- 0.00 24.37 s --- --- --- --- 27.49 4.55 2,400 549.25 27.74 is 3.04 is --- --- 0.00 24.70 s --- --- --- --- 27.73 4.59 2,404 549.29 27.98 is 2.96 is --- --- 0.01 25.00 s --- --- --- --- 27.98 ... End Hydrograph Summary ReportH ydraflow Hydrographs Extension for Autodesk®Civil 3D® 2019 by Autodesk, Inc. v2020 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cuft) Inflow hyd(s) Maximum elevation (ft) Total strge used (cuft) Hydrograph Description 1 Rational 12.79 1 5 3,836 ------ ------ ------ Area to Outfall B Detention 2 Reservoir 7.265 1 7 3,592 1 547.55 1,602 Detention Pipe B Ivy Detention Pipes-Rational.gpw Return Period: 10 Year Friday, 11 / 30 / 2018 9 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Friday, 11 / 30 / 2018 Hyd. No. 1 Area to Outfall B Detention Hydrograph type = Rational Peak discharge = 12.79 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 3,836 cuft Drainage area = 2.558 ac Runoff coeff. = 0.75 Intensity = 6.666 in/hr Tc by User = 5.00 min OF Curve = Ivy.IDF Asc/Rec limb fact = 1/1 Q (cfs) 14.00 12.00 10.00 8.00 6.00 4.00 2.00 0 00 0 1 2 Hyd No. 1 Area to Outfall B Detention Hyd. No. 1 -- 10 Year Q (cfs) 14.00 12.00 J/ 10.00 8.00 0 OF 6.00 4.00 2.00 0.00 3 4 5 6 7 8 9 10 Time (min) Hydrograph Report 10 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Hyd. No. 2 Detention Pipe B Hydrograph type = Reservoir Peak discharge Storm frequency = 10 yrs Time to peak Time interval = 1 min Hyd. volume Inflow hyd. No. = 1 - Area to Outfall B Detention Max. Elevation Reservoir name = Outfall B Detention Pipe Max. Storage Storage Indication method used. Q (cfs) 14.00 12.00 10.00 • 11 4.00 2.00 Detention Pipe B Hyd. No. 2 -- 10 Year Friday, 11 / 30 / 2018 = 7.265 cfs = 7 min = 3,592 cuft = 547.55 ft = 1,602 cuft Q (cfs) 14.00 12.00 10.00 lllll. 11 4.00 2.00 0.00 W V I I I I I I I I r I I I I 1.j 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Time (min) Hyd No. 2 Hyd No. 1 I_I_I_I_I_I_1 Total storage used = 1,602 cuft 11 Hydrograph Summary ReportH ydraflow Hydrographs Extension for Autodesk®Civil 3D® 2019 by Autodesk, Inc. v2020 Hyd. No. Hydrograph type (origin) Peak flow (cfs) Time interval (min) Time to Peak (min) Hyd. volume (cuft) Inflow hyd(s) Maximum elevation (ft) Total strge used (cuft) Hydrograph Description 1 Rational 16.81 1 5 5,043 ------ ------ ------ Area to Outfall B Detention 2 Reservoir 12.01 1 6 4,799 1 548.07 1,932 Detention Pipe B Ivy Detention Pipes-Rational.gpw Return Period: 100 Year Friday, 11 / 30 / 2018 12 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Friday, 11 / 30 / 2018 Hyd. No. 1 Area to Outfall B Detention Hydrograph type = Rational Peak discharge = 16.81 cfs Storm frequency = 100 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 5,043 cuft Drainage area = 2.558 ac Runoff coeff. = 0.75 Intensity = 8.762 in/hr Tc by User = 5.00 min OF Curve = Ivy.IDF Asc/Rec limb fact = 1/1 Q (cfs) 18.00 15.00 12.00 •M am 3.00 Area to Outfall B Detention Hyd. No. 1 -- 100 Year Q (cfs) 18.00 15.00 12.00 M 3.00 0.00 It ' ' ' ' ' ' ' ' ' N 0.00 0 1 2 3 4 5 6 7 8 9 10 Hyd No. 1 Time (min) 13 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Friday, 11 / 30 / 2018 Hyd. No. 2 Detention Pipe B Hydrograph type = Reservoir Peak discharge = 12.01 cfs Storm frequency = 100 yrs Time to peak = 6 min Time interval = 1 min Hyd. volume = 4,799 cuft Inflow hyd. No. = 1 - Area to Outfall B Detention Max. Elevation = 548.07 ft Reservoir name = Outfall B Detention Pipe Max. Storage = 1,932 cuft Storage Indication method used. Q (cfs) 18.00 15.00 12.00 •m .M 3.00 0.00 W " 0 2 Hyd No. 2 Detention Pipe B Hyd. No. 2 -- 100 Year 4 6 Hyd No. 1 8 10 12 14 I_I_I_I_I_I_I Total storage used = 1,932 cuft Q (cfs) 18.00 15.00 12.00 m 3.00 0.00 16 Time (min) Hydraflow Rainfall Report 14 Hydraflow Hydrographs Extension for Autodesk® Civil 3D® 2019 by Autodesk, Inc. v2020 Precip. file Return Period Intensity -Duration -Frequency Equation Coefficients (FHA) (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 0.0000 0.0000 0.0000 -------- 10 46.9500 9.5000 0.7300 -------- 25 0.0000 0.0000 0.0000 -------- 50 0.0000 0.0000 0.0000 -------- 100 31.0900 5.0000 0.5500 -------- File name: Ivy.IDF Intensity = B / (Tc + D)^E Friday, 11 / 30 / 2018 Return Period Intensity Values (in/hr) (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 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 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 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 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. name: K:\Kiu UV\ i -i Storm susu - AIDemane ury un-uau\zu_ivyKa\tngineering\uompuiauons\h arauncsuv . c Rainfall Precipitation Table (in) Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 3.04 3.68 0.00 0.00 5.56 6.83 7.92 9.12 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-4th 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 APPENDIX F Kimley>>Morn Storm Drain Design Calculations VDOT LD-229 Outfall A - Upstream of Detention - Proposed Project: Ivy Road Sidewalk Improvements Project #: 0250-002-R98 Date: 11 /29/2018 Locality: Albemarle 10 -year storm Manning n = 0.013 FROM POINT TO POINT DRAINAGE AREA RUNOFF COEFFICIENT CA INLETTIME RAINFALL RUNOFF INVERT ELEVATIONS LENGTH SLOPE SIZE PIPE CAPACITY Q/Q VELOCITY FLOWTIME REMARKS inlet accum upper end lower end incr accum acres C min in/hr cfs ft ft ft % in cfs % fps min 3-1 3-2 0.33 0.75 0.244 0.244 5.00 6.67 1.64 564.00 562.50 52 0.029 15 11.02 15% 6.44 0.13 5.00 3-2 3-3 0.40 0.75 0.302 0.545 5.00 6.62 3.64 560.50 557.30 62 0.051 15 14.64 25% 9.90 0.11 5.13 3-3 3-4 1.13 0.85 0.959 1.504 6.00 6.35 9.63 557.20 555.80 52 0.027 18 17.19 56% 10.00 0.09 6.00 Kimley)))Horn Hydraulic Grade Line Calculations Project: Ivy Road Sidewalk Improvements Project M 0250-002-R98 Date: 11 /29/2018 Locality: Albemarle VDOT LD-347 Outfall A - Upstream of Detention - Proposed 10 -year storm Angle 0 15 20 25 30 40 50 60 70 80 90 K 0 0.19 0.25 0.30 0.35 0.43 0.50 0.56 0.61 0.66 0.70 INLET 0.81)+ INV (OUT) ACTUAL OUTLET WSE DESIGN OUTLET WSE Do Qo Lo Sfo Hf JUNCTION LOSS FINAL H INLET WSE F/L ELEV Vo (8) Ho (9) Q (10) V; (11) Q;V; (12) V,. Zg H; Angle Ho Ht Surface Runoff Factor? 1.3 H, IS-1? 0.5 Ht (1) (2) (3) (4) (5) (6) (7) (13) (14) (15) (16) (17) (18) (19) (20) (21) 3-3 557.00 557.49 557.49 18 9.63 52 0.0084 0.44 10.00 0.39 3.64 9.90 36.04 1.52 0.53 0 0.00 0.92 YES 1.20 YES 0.60 1.04 558.53 563.90 3-2 558.30 558.53 558.53 15 3.64 62 0.0032 0.20 9.90 0.38 1.64 6.44 10.56 0.64 0.23 20 0.16 0.77 YES 1.00 YES 0.50 0.70 559.22 566.63 3-1 563.50 559.22 563.50 15 1.64 52 0.0006 0.03 6.44 0.16 0.00 0.00 0.00 0.00 0.00 0 0.00 0.16 YES 0.21 YES 0.10 0.14 563.64 568.17 Outfall A - Upstream of Detention - Proposed Storm CAD HGL Computations - Proposed - 30yr - Upstream of Detention Pipe A Non -Piped Contraction Bend Loss Bend Loss Bend Loss Bend Loss Expansion Loss P Is Non -Piped P Correction Energy Downstream Downstream Downstream Hydraulic y EnergyContrac-tion Loss Coef- Bend Loss Pipe Angle Conduit Flow Pipe Velocity Pipe Velocity Bend Loss Bend Loss Expansion Loss P Expansion Loss P Expansion Loss Pipe Velocity Expansion Loss P Expansion Loss Flow Flow AASHTO factor for Unadjusted I Adjusted t Hydraulic y Grade Label Downstream Conduit Conduit Flow ids) Conduit Velocity (k/s) Conduit Velocity Head (k) Grade Une (Out) Grade Une (Out) (ft) ficient Loss (AASHTO) (h) Controlling Pipe (AASHTO) (AASHTO) (AASHTO) (AASHTO) Head Coefficient (AASHTO) (AASHTO) (h) Controlling Pipe (AASHTO) Pipe Flow (AASHTO) (cfs) i Pipe Velocity (AASHTO) (h/s) Head Coefficient (AASHTO) (AASHTO) (h) Significant? Correction Factor Shaping Method shaping Headloss (AASHTO) (h) Headloss (AASHTO) (h) Grade Line (In) (h) Line (In) (AASHTO) (degrees) (cfs) (h/s) (AASHTO) (ft) (AASHTO) (h) (AASHTO) (AASHTO) (AASHTO) (ft) 3-3 3-3 to 3-4 9.63 6.36 0.6 558.3980713 559.03 0.25 0.16 3-2 to 3-3 4.53 3.64 2.97 0.14 0.057 0.01 3-2 to 3-3 3.64 2.97 0.14 0.35 0.05 TRUE 1.3 Full 0.5 0.21 0.14 558.54 558.67 3-2 3-2 to 3-3 3.64 4.58 0.3 561.2706299 561.6 0.25 0.08 3-1 to 3-2 17.67 1.64 1.33 0.03 0.218 0.01 3-1 to 3-2 1.64 1.33 0.03 0.35 0.01 TRUE 1.3 Full 0.5 0 0 561.27 561.92 3-1 3-1 to 3-2 1.64 3.5 0.2 564.5077515 564.7 0.25 0.05 0 0 0 0 0 0 0 0 0 0 0 TRUE 1.3 Full 0.5 0.05 0.03 1 564.54 564.73 Kimley>>Morn Storm Drain Design Calculations VDOT LD-229 Outfall A - Downstream of Detention - Proposed Project: Ivy Road Sidewalk Improvements Project #: 0250-002-R98 Date: 11 /30/2018 Locality: Albemarle 10 -year storm Manning n = 0.013 FROM POINT TO POINT DRAINAGE AREA RUNOFF COEFFICIENT CA INLETTIME RAINFALL RUNOFF INVERT ELEVATIONS LENGTH SLOPE SIZE PIPE CAPACITY Q/Qi VELOCITY FLOW TIME REMARKS inlet accum upper end lower end incr I accum acres C min in/hr cfs ft ft ft % in cfs % fps min 3-6 3-7 (N/A) (N/A) 0.000 0.000 0.00 6.67 7.36* 554.50 554.45 10 0.005 24 16.00 46% 4.99 0.03 0.00 #434 3-7 3.22 0.60 1.932 1.932 10.00 5.37 10.46 557.84 554.45 127 0.027 24 36.96 28% 10.12 0.21 10.00 3-7 #435 0.00 0.00 0.000 1.932 0.00 5.33 17.74 554.45 553.14 50 0.026 24 36.62 48% 11.56 0.07 10.21 #435 #437 0.15 0.60 0.090 2.022 15.00 4.55 16.62 553.11 545.57 238 0.032 24 40.26 41% 12.20 0.33 15.00 #437 #451 2.11 0.65 1.372 3.394 5.00 4.50 41.12 543.30 538.22 273 0.019 24 30.86 133% 13.09 0.46 15.33 SURCHARGED #451 #452 0.80 0.85 0.680 4.074 9.00 4.46 56.12 537.45 536.83 92 0.007 36 54.75 103% 7.94 0.20 15.67 SURCHARGED #452 #452 (Out) 15.57 0.75 11.678 15.751 14.00 4.43 149.61 536.62 536.02 52 0.012 36 71.64 209% 21.16 1 0.04 15.87 SURCHARGED Project: Ivy Road Sidewalk Improvements Kim l ey >>> H o r n Project M 0250-002-R98 Date: 11 /30/2018 Hydraulic Grade Line Calculations Locality: Albemarle VDOT LD-347 Outfall A - Downstream of Detention - 10 -year storm INLET 0.8D+ INV (OUT) ACTUAL OUTLET WSE DESIGN OUTLET WSE Do Qo Lo Sfo Hr JUNCTION LOSS FINALH INLET WSE F/L ELEV Vo (8) Ho (9) Q (10) V; (11) Q;V; (12) z V,. Zg H; Angle Ho H, Surface Runoff Factor? 1.3 H, IS -I? 0.5 H, (1) (2) (3) (4) (5) (6) (7) (13) (14) (15) (16) (17) (18) (19) (20) (21) #452 538.42 538.42 538.42 36 149.61 52 0.0503 2.62 21.16 1.74 56.12 7.94 445.59 0.98 0.34 60 0.55 2.63 YES 3.42 YES 1.71 4.33 542.68 #451 539.23 542.75 542.75 36 56.12 92 0.0071 0.65 7.94 0.24 41.12 13.09 538.26 2.66 0.93 0 0.00 1.18 YES 1.53 YES 0.76 1.42 544.16 546.25 #437 539.82 544.16 544.16 24 41.12 273 0.0330 9.02 13.09 0.67 16.62 12.20 202.76 2.31 0.81 0 0.00 1.47 YES 1.92 YES 0.96 9.98 551.55 #435 547.17 554.14 554.14 24 16.62 238 0.0054 1.28 12.20 0.58 17.74 11.56 205.07 2.08 0.73 50 1.04 2.34 NO 2.34 YES 1.17 2.46 556.60 558.22 3-7 554.74 556.60 556.60 24 17.74 50 0.0062 0.31 11.56 0.52 10.46 10.12 105.86 1.59 0.56 90 1.11 2.19 NO 2.19 YES 1.09 1.40 558.00 559.88 #434 556.05 558.00 558.00 24 10.46 127 0.0021 0.27 10.12 0.40 0.00 0.00 0.00 0.00 0.00 0 0.00 0.40 YES 0.52 YES 0.26 0.53 558.53 567.46 3-6 556.05 558.00 558.00 24 7.36 10 0.0011 0.01 4.99 0.10 0.00 0.00 0.00 0.00 0.00 0 0.00 0.10 YES 0.13 YES 0.06 0.07 558.07 560.83 Outfall A - Downstream of Detention - Proposed StormCAD HGL Computations - Proposed - 10yr - To Outfall A Expansion Expansion Non -Piped Contraction Bend Loss Bend Loss Bend Loss Expansion Loss Expansion Is Non -Piped Correction Downstream Downstream Downstream Hydraulic Energy Loss Coef- Contrac- tion Bend Loss Pipe Angle Bend Loss Pipe Velocity Pipe Velocity Bend Loss Bend Loss Expansion Loss Loss Pipe Loss Pipe Pipe Velocity Loss Expansion Flow Flow AASHTO factor for Unadjusted Adjusted Hydraulic Energy Label Downstream Conduit Conduit Flow Conduit Velocity Conduit Velocity Grade Line Grade Line Loss Controlling Pipe Conduit Flow Coef-ficient (AASHTO) Controlling Pipe Flow Velocity Loss (AASHTO) Correction Shaping Headloss Headloss Grade Line Grade Line (cfs) (ft/s) Head (it) (Out) (Out) (ft) ficient (AASHTO) (ft) (AASHTO) (AASHTO) (AASHTO) (cfs) (AASHTO) Head (AASHTO) (k) (AASHTO) (AASHTO) (AASH) Head Coefficient (ft) Significant? Factor Method shaping (AASHTO) (ft) (AASHTO) (ft) (In) (ft) (In) (ft) (AASHTO) (degrees) (ft/s) (AASHTO) (ft) (AASHTO)(ft) (AASHTO) (AASHTO) (AASHTO) (cfs) ) (k/s (AASHTO) #452 #452 to #452 (Out) 149.61 21.16 7 541.6289673 548.59 0.25 1.74 #451 to #452 57.94 56.12 7.94 0.98 0.548 0.54 #451 to #452 56.12 7.94 0.98 0.35 0.34 TRUE 1.3 Full 0.5 2.62 1.7 543.33 544.31 #451 #451 to #452 56.12 7.94 1 543.3312988 544.31 0.25 0.24 #437 to #451 5.05 41.12 13.09 2.66 0.064 0.17 #437 to #451 41.12 13.09 2.66 0.35 0.93 TRUE 1.3 Full 0.5 1.35 0.88 544.21 546.87 #437 #437 to #451 41.12 13.09 1 2.7 551.5499878 554.21 0.25 0.67 #435 to #437 7.48 16.62 5.29 0.44 0.095 0.04 #435 to #437 16.62 5.29 0.44 0.35 0.15 TRUE 1.3 Full 0.5 0 0 551.55 551.99 #435 #435 to #437 16.62 6.72 0.7 554.5802612 555.28 0.25 0.18 3-7 to #435 50.98 17.74 6.03 0.57 0.506 0.29 3-7 to #435 17.74 6.03 0.57 0.35 0.2 FALSE 1 Full 0.5 0.66 0.33 554.91 555.48 #434 #434 to 3-7 10.46 5.54 0.5 558.9994131 559.48 0.25 0.12 0 0 0 0 0 0 0 0 0 0 0 TRUE 1.3 Full 0.5 0.12 0.08 559.08 559.55 3-7 3-7 to #435 17.74 6.93 0.7 555.9676514 556.71 0.25 0.19 3-6 to 3-7 94.46 7.36 2.6 0.11 0.718 0.08 #434 to 3-7 10.46 3.7 0.21 0.35 0.07 FALSE 1 Full 0.5 0.34 0.17 556.14 556.24 3-6 3-6 to 3-7 7.36 2.67 0.1 556.1411133 556.25 0.25 0.03 0 0 0 0 0 0 0 0 0 0 0 TRUE 1.3 Full 0.5 0.03 0.02 556.16 556.27 Kimley>>Morn Storm Drain Design Calculations VDOT LD-229 Outfall B - Upstream of Detention - Proposed Project: Ivy Road Sidewalk Improvements Project #: 0250-002-R98 Date: 8/22/2017 Locality: Albemarle 10 -year storm Manning n = 0.013 FROM POINT TO POINT DRAINAGE AREA RUNOFF COEFFICIENT CA INLETTIME RAINFALL RUNOFF INVERT ELEVATIONS LENGTH SLOPE SIZE PIPE CAPACITY Q/Q VELOCITY FLOWTIME REMARKS inlet accum upper end lower end incr accum acres C min in/hr cfs ft ft ft % in cfs % fps min 3-10 4-1 0.31 0.75 0.230 0.230 5.00 6.67 1.55 564.70 558.80 172 0.034 15 11.96 13% 6.72 0.43 5.00 4-1 4-2 0.88 0.80 0.702 1.475 5.00 6.53 9.70 554.90 550.00 174 0.028 18 17.63 55% 10.21 0.28 5.43 4-5 4-6 0.31 0.70 0.218 0.218 5.00 6.67 1.46 559.00 558.50 17 0.029 15 11.08 13% 6.26 0.05 5.00 4-6 4-1 0.43 0.75 0.326 0.543 5.00 6.65 3.64 558.40 558.00 13 0.031 15 11.33 32% 8.22 0.03 5.05 Kimley)))Horn Hydraulic Grade Line Calculations VDOT LD-347 Outfall B - Upstream of Detention - Project: Ivy Road Sidewalk Improvements Project M 0250-002-R98 Date: 8/22/2017 Locality: Albemarle 10 -year storm INLET O.SD+ INV (OUT) ACTUAL OUTLET WSE DESIGN OUTLET WSE Do Qo Lo Sfo Hf JUNCTION LOSS FINAL H INLET WSE F/L ELEV Vo (8) Ho (9) Q; (10) V; (11) Q;V; (12) z V,. Zg H; Angle Ho H, Surface Runoff Factor? 1.3 H, IS -I? 0.5 H, (1) (2) (3) (4) (5) (6) (7) (13) (14) (15) (16) (17) (18) (19) (20) (21) 4-1 551.20 551.20 551.20 18 9.70 174 0.0085 1.48 10.21 0.40 3.64 8.22 29.92 1.05 0.37 90 0.73 1.51 YES 1.96 YES 0.98 2.46 553.66 562.32 3-10 559.80 553.66 559.80 15 1.55 172 0.0006 0.10 6.72 0.18 0.00 0.00 0.00 0.00 0.00 0 0.00 0.18 YES 0.23 YES 0.11 0.21 560.01 568.14 4-6 559.00 553.66 559.00 15 3.64 13 0.0032 0.04 8.22 0.26 1.46 6.26 9.14 0.61 0.21 50 0.30 0.78 YES 1.01 YES 0.51 0.55 559.55 561.50 4-5 559.50 559.55 559.55 15 1.46 17 0.0005 0.01 6.26 0.15 0.00 0.00 0.00 0.00 0.00 0 0.00 0.15 YES 0.20 YES 0.10 0.11 559.66 563.20 Outfall B - Upstream of Detention - Proposed StormCAD HGL Computations - Proposed - 10yr - Upstream of Detention Pipe B Label Downstream Conduit Downstream Conduit Flow (cfs) Downstream Conduit Velocity (ft/s) Downstream Conduit Velocity Head (ft) Hydraulic Grade Line (Out) Energy Grade Line (Out) (ft) Contraction Loss Coefficient (AASHTO) Contraction Loss (AASHTO) (ft) Bend Loss Controlling Pipe (AASHTO) Bend Loss Pipe Angle (AASHTO) (degrees) Bend Loss Conduit Flow (AASHTO) (cfs) Bend Loss Pipe Velocity (AASHTO) NO Bend Loss Pipe Velocity Head (AASHTO) (ft) Bend Loss Coefficient (AASHTO) Bend Loss (AASHTO) (ft) Expansion Loss Controlling Pipe (AASHTO) Expansion Loss Pipe Flow (AASHTO) (cfs) Expansion Loss Pipe Velocity (AASHTO) (f O Expansion Loss Pipe Velocity Head (AASHTO) (ft) Expansion Loss Coefficient (AASHTO) Expansion Loss (AASHTO) (ft) Is Non -Piped Flow Significant? (AASHTO) Non -Piped Flow Correction Factor (AASHTO) AASHTO Shaping Method Correction factor for shaping (AASHTO) Unadjusted Headloss (AASHTO) (ft) Adjusted Headloss (AASHTO) (ft) Hydraulic Grade Line (In) (ft) Energy Grade Line (In) (ft) 3-10 3-10to4-1 1.55 3.44 0.2 565.1928101 565.38 0.25 0.05 0 0 0 0 0 0 0 0 0 0 0 TRUE 1.3 Full 0.5 0.05 0.03 565.22 565.41 4-1 4-1 to 4-2 9.7 6.39 0.6 556.102417 556.74 0.25 0.16 4-6 to 4-1 92.57 3.64 2.97 0.14 0.71 0.1 4-6 to 4-1 3.64 2.97 0.14 0.35 0.05 TRUE 1.3 Full 0.5 0 0 556.1 556.86 4-6 4-6 to 4-1 3.64 4.58 0.3 559.1708984 559.5 0.25 0.08 4-5 to 4-6 50.26 1.46 1.89 0.06 0.502 0.03 4-5 to 4-6 1.46 1.89 0.06 0.35 0.02 TRUE 1.3 Full 0.5 0.13 0.08 559.25 559.31 4-5 4-5 to 4-6 1.46 3.38 0.2 559.4785156 559.66 0.25 0.04 0 0 0 0 0 0 0 0 0 0 0 TRUE 1.3 Full 0.5 0.04 0.03 559.51 559.69 Kimley>>Morn Storm Drain Design Calculations VDOT LD-229 Outfall B - Downstream of Detention - Proposed Project: Ivy Road Sidewalk Improvements Project #: 0250-002-R98 Date: 8/22/2017 Locality: Albemarle 10 -year storm Manning n = 0.013 FROM POINT TO POINT DRAINAGE AREA RUNOFF COEFFICIENT CA INLETTIME RAINFALL RUNOFF INVERT ELEVATIONS LENGTH SLOPE SIZE PIPE CAPACITY Q/Qi VELOCITY FLOW TIME REMARKS inlet accum upper end lower end incr I accum acres C min in/hr cfs ft ft ft % in cfs % fps min 4-3 4-4 (N/A) (N/A) 0.000 0.000 0.00 6.67 7.27 544.60 544.30 24 0.013 24 25.29 29% 6.96 0.06 0.00 4-4 EX. 4-7 (N/A) (N/A) 0.000 0.000 0.00 6.67 7.27 543.20 543.00 11 0.018 24 30.50 24% 7.96 0.02 0.06 EX. 4-7 #415 0.38 0.75 0.285 0.285 5.00 6.67 9.18 542.03 541.34 53 0.013 24 25.81 36% 7.52 0.12 5.00 #415 1 #400 0.38 1 0.75 0.285 1 0.570 5.00 1 6.63 11.08 541.32 1 538.37 131 1 0.023 24 1 33.95 33% 9.66 0.23 5.12 #400 #401 0.46 0.75 0.345 0.915 5.00 6.55 13.31 538.30 536.77 61 0.025 24 35.83 37% 10.56 0.10 5.34 #401 #421-A 0.93 0.80 0.744 1.659 5.00 6.52 18.18 536.70 535.93 98 0.008 24 20.05 91% 5.79 0.28 1 5.44 #421-A #405 (N/A) (N/A) 0.000 1.659 0.00 6.43 18.03 535.93 535.56 47 0.008 24 20.07 90% 5.74 0.14 5.72 #405 #406 0.03 0.55 0.017 1.676 5.00 6.39 18.06 535.52 535.33 24 0.008 24 20.13 90% 5.75 0.07 5.86 #406 #409 23.17 0.60 13.902 15.578 15.13 4.53 78.36 535.05 529.23 185 0.031 24 40.12 195% 24.94 0.12 15.13 SURCHARGED #409 #409 (Out) 0.79 0.50 0.395 15.972 5.00 4.51 79.90 528.19 526.50 73 0.023 30 62.41 128% 16.28 0.08 15.25 ISURCHARGED Kimley)))Horn Hydraulic Grade Line Calculations VDOT LD-347 Outfall B - Downstream of Detention - Project: Ivy Road Sidewalk Improvements Project M 0250-002-R98 Date: 8/22/2017 Locality: Albemarle 10 -year storm INLET 0.8D+ INV (OUT) ACTUAL OUTLET WSE DESIGN OUTLET WSE Do Qo L. Sfo Hf JUNCTION LOSS FINAL INLET F/L WSE ELEV Vo (8) Ho (9) Q (10) V; (11) Q;V; (12) z V,. Zg H; Angle Ho H, Surface Runoff Factor? 1.3 H, IS-17 0.5 H, (1) (2) (3) (4) (5) (6) (7) (13) (14) (15) (16) (17) (18) (19) (20) (21) #409 528.50 529.00 529.00 30 79.90 73 0.0380 2.77 16.28 1.03 78.36 24.94 1954.30 9.66 3.38 40 4.15 8.56 NO 8.56 YES 4.28 7.05 r 534.80 #406 530.83 536.05 536.05 24 78.36 185 0.1200 22.20 24.94 2.41 18.06 5.75 103.85 0.51 0.18 90 0.36 2.95 YES 3.84 YES 1.92 24.12 537.57 #405 536.93 560.18 560.18 24 18.06 24 0.0064 0.15 5.75 0.13 18.03 5.74 103.49 0.51 0.18 90 0.36 0.67 NO 0.67 YES 0.33 0.49 .� .. 538.36 #421-A 537.16 560.66 560.66 24 18.03 47 0.0064 0.30 5.74 0.13 18.18 5.79 105.26 0.52 0.18 0 0.00 0.31 NO 0.31 YES 0.16 0.45 542.23 #401 537.53 561.11 561.11 24 18.18 98 0.0065 0.63 5.79 0.13 13.31 10.56 140.55 1.73 0.61 15 0.33 1.07 YES 1.38 YES 0.69 1.33 541.39 #400 538.37 562.44 562.44 24 13.31 61 0.0035 0.21 10.56 0.43 11.08 9.66 107.03 1.45 0.51 0 0.00 0.94 YES 1.22 YES 0.61 0.82 543.33 #415 539.97 563.26 563.26 24 11.08 131 0.0024 0.31 9.66 0.36 9.18 7.52 69.03 0.88 0.31 0 0.00 0.67 YES 0.87 YES 0.44 0.75 r 547.38 EX. 4-7 542.94 564.01 564.01 24 9.18 53 0.0016 0.09 7.52 0.22 7.27 7.96 57.87 0.98 0.34 0 0.00 0.56 YES 0.73 YES 0.37 0.45 548.56 4-4 544.60 564.47 564.47 24 7.27 11 0.0010 0.01 7.96 0.25 7.27 6.96 50.60 0.75 0.26 30 0.26 0.77 NO 0.77 YES 0.39 0.40 550.63 4-3 545.90 564.86 564.86 24 7.27 24 0.0010 0.02 6.96 0.19 0.00 0.00 0.00 0.00 0.00 0 0.00 0.19 YES 0.24 YES 0.12 0.15 r 551.10 Outfall B - Downstream of Detention - Proposed StormCAD HGL Computations - Proposed -10yr - To Outfall B Bend Loss Expansion Bend Loss Bend Loss Expansion Expansion Non -Piped Downstream Contraction Contraction Bend Loss Pipe Loss Pipe Expansion Expansion Is Non -Piped Correction Unadjusted Adjusted Hydraulic Energy Downstream Downstream Conduit Hydraulic Energy Loss Loss Bend Loss Pipe Angle Conduit Pipe Velocity Bend Loss Bend Loss Expansion Loss Loss Pipe Loss Pipe Velocity Loss Loss Flow Flow AASHTO factor for Headloss Headloss Grade Grade Label Downstream Conduit Conduit Flow Conduit Grade Line Grade Line Controlling Pipe Flow Velocity Coefficient (AASHTO) Controlling Pipe Flow Velocity Correction Shaping Velocity Head Coefficient (AASHTO) (AASHTO) Head Head Coefficient (AASHTO) Significant? shaping (AASHTO) (AASHTO) Line (In) Line (In) (cfs) Velocity (ft/s) Ift) (Out) (Out) (ft) (AASHTO) (ft) (AASHTO) (degrees) (AASHTO) (AASHTO) (AASHTO) (AASHTO) (ft) (AASHTO) (AASHTO) (AASHTO) (AASHTO) (AASHTO) (ft) (AASHTO) Factor Method (AASHTO) Ift) (ft) (ft) (ft) (cfs) (ft/s) (cfs) (ft/s) (AASHTO) (ft) (ft) 4-3 4-3to4-4 7.27 4.89 0.4 545.5575562 545.93 0.25 0.09 0 0 0 0 0 0 0 0 0 0 0 TRUE 1.3 Full 0.5 0.09 0.06 545.62 545.99 4-4 4-4 to EX. 4-7 7.27 4.89 0.4 544.1575317 544.53 0.25 0.09 4-3 to 4-4 31.95 7.27 10.68 1.77 0.366 0.65 4-3 to 4-4 7.27 10.68 1.77 0.35 0.62 FALSE 1 Full 0.5 1.36 0.68 544.84 545.49 EX. 4-7 EX. 4-7 to #415 9.18 5.29 0.4 543.1124878 543.55 0.25 0.11 4-4 to EX. 4-7 0.16 7.27 10.21 1.62 0.002 0 4-4 to EX. 4-7 7.27 10.21 1.62 0.35 0.57 TRUE 1.3 Full 0.5 0.68 0.44 543.55 544.22 #415 #415 to #400 11.08 5.66 0.5 542.5139771 543.01 0.25 0.12 EX. 4-7 to #415 3.17 9.18 4.17 0.27 0.04 0.01 EX. 4-7 to #415 9.18 4.17 0.27 0.35 0.09 TRUE 1.3 Full 0.5 0.23 0.15 542.66 542.93 #400 #400 to #401 13.31 6.09 0.6 539.6134033 540.19 0.25 0.14 #415 to #400 1.77 11.08 4.65 0.34 0.022 0.01 #415 to #400 11.08 4.65 0.34 0.35 0.12 TRUE 1.3 Full 0.5 0.27 0.17 539.79 540.12 #401 #401 to #421-A 18.18 5.79 0.5 539.447937 539.97 0.25 0.13 #400 to #401 8.28 13.31 4.24 0.28 0.105 0.03 #400 to #401 13.31 4.24 0.28 0.35 0.1 TRUE 1.3 Full 0.5 0.26 0.17 539.61 539.89 #421-A #421-A to #405 18.03 5.74 0.5 538.6585083 539.17 0.25 0.13 #401 to #421-A 0.52 18.18 5.79 0.52 0.007 0 #401 to #421-A 18.18 5.79 0.52 0.35 0.18 FALSE 1 Full 0.5 0.31 0.16 538.82 539.34 #405 #405 to #406 18.06 5.75 0.5 538.2230225 538.74 0.25 0.13 #421-A to #405 87.85 18.03 5.74 0.51 0.691 0.35 #421-A to #405 18.03 5.74 0.51 0.35 0.18 FALSE 1 Full 0.5 0.66 0.33 538.55 539.07 #406 #406 to #409 78.36 24.94 9.7 538.0700073 547.74 0.25 2.42 #405 to #406 90.17 18.06 5.75 0.51 0.701 0.36 #405 to #406 18.06 5.75 0.51 0.35 0.18 TRUE 1.3 Full 0.5 2.96 1.92 539.99 540.51 #409 #409 to #409 (Out) 1 79.9 16.28 1 4.1 531.7703247 1 535.89 1 0.25 1.03 1 #406 to #409 43.84 1 78.36 1 24.94 1 9.67 1 0.461 4.45 #406 to #409 1 78.36 1 24.94 9.67 1 0.35 3.38 FALSE 1 Full 1 0.5 8.87 4.43 536.2 545.87 Road: Ivy Project#: 0250-002-1198 VDOT ROADWAY SPREAD ANALYSIS REPORT Units: U.S. Customary Metric (SI) Sheet: of Prepared by: JHO Checked by: MRM Composite Rainfall Inlet Previous Total Cross Logitudinal Gutter/Local Gutter Calculated Allowable ComputedSlot Sumped Ponded Structure VDOT Manning's Station Offset a Runoff Intensity Discharge Inlet Bypass Discharge Slope Slope Depress. Width Slope Spread Spread o Length (100 /o Eff.) Spread Depth No. StandardCoefficient in/hr) (cfs) (cfs) (cfs) (ft/ft % ft ft/ft n" ft ft ft ft ft 3-3 200+48.24 -20.18 DI-3B 16 1.13 0.85 4.00 3.84 0.00 3.84 0.012 2.2300 2.0000 0.0833 0.015 11.79 8.00 15.47 N/A 0.28 3-2 120+00.00 21.50 1-313 18 No Gutt 0.40 0.75 4.00 1.21 0.00 1.21 0.020 2.9294 1.0000 0.0200 0.015 6.19 8.00 16.65 N/A 0.12 3-1 120+54.00 21.50 1-313 16 No Guttl 0.32 0.75 4.00 0.97 0.00 0.97 0.020 2.8784 1.0000 0.0200 0.015 5.73 10.00 14.77 N/A 0.11 Remarks: HEC-12 is used for spread and bypass computations All other computations done using GEOPAK Drainage Road: Ivy Project #: 0250-002-R98 VDOT ROADWAY SPREAD ANALYSIS REPORT Units: U.S. Customary Metric (SI) Sheet: of Prepared by: MRM Date: 8/22/2017 Checked by: BAM Date: 8/22/2017 Drainage Composite Rainfall Inlet Previous Total Cross Logitudinal Gutter/Local Gutter Calculated Allowable ComputedSlot Sumped Ponded Intercepted Bypass Flow Bypass to Structure Station Offset V Area Runoff Intensity Discharge Inlet Bypass Discharge Slope Slope Depress. Width Slope Manning's Spread Spread u Length (100 /o Eff.) Spread Depth Flow to Next Inlet Structure No. Standard acres Coefficient in/hr) (cfs) (cfs) (cfs) (ft/ft % (ft) (ft/ft n ft ft ft ft ft) (cfs) (cfs No. 4-3 128+72.00 32.50 DI-4E 16 No Gutter 0.25 0.85 4.00 0.97 0.13 1.10 0.020 3.1648 1.0000 0.0200 0.015 5.62 8.00 15.06 N/A 0.11 1.10 0.00 4-2 126+77.00 21.50 DI-4EE 16 No Gutter 0.38 0.85 4.00 1.85 0.55 2.40 0.020 2.8069 1.0000 0.0200 0.015 7.32 8.00 20.68 N/A 0.15 2.27 0.13 4-3 4-1 125+00.00 21.50 DI-3B 16 No Gutter 0.88 0.80 4.00 2.81 0.00 2.81 0.020 3.3109 1.0000 0.0200 0.015 8.30 10.00 26.91 N/A 0.17 2.25 0.55 4-2 3-10 123+25.00 21.50 DI-3B 14 No Gutter 0.31 0.75 4.00 0.92 0.00 0.92 0.020 2.4730 1.0000 0.0200 0.015 5.77 8.00 13.83 N/A 0.12 0.92 0.00 4-1 Remarks: HEC-12 is used for spread and bypass computations All other computations done using GEOPAK Drainage Project: Ivy Road Sidewalk Improvements Grate Inlet Calcs 11/30/2018 Structure Type Area, A Perimeter, P Ponding Depth Allowable, d Weir Control Flow, Qw Orifice Control Flow, Q. Design Capacity, QdP, Actual Flow, Qnwai Qdes>Qa«uai ft2 ft ft cfs cfs cfs cfs 4-6 Std. DI-7; Grate A Type III 3.25 12.80 1.56 37.41 10.91 10.91 2.19 OKAY 5-2 Std. DI-7; Grate A Type 1 6.00 12.80 1.71 42.93 21.09 21.09 50.69 NO