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HomeMy WebLinkAboutDrainage Report-BDX003Drainage Calculations Ashmoor Residential Subdivision (PUD) 131st Street & Shelborne Road Carmel, Indiana 46032 Job #: BDX.003 Date: 10 -17 -13 Prepared by: Eric A. Gleissner, P.E. Reviewed by: Brian Cross, P.E. ,s011 II 1111 1111/00. PC? x03358 • (70-7390 ': STMT pF CiviI Site GROUP, INC 643 Massachusetts Avenue Suite 200 Indianapolis, IN 46204 Phone: 317- 423 -3305 Fax: 317- 423 -3306 TABLE OF CONTENTS Section 1: Report A. Project Title B. Project Description C. Design Method and Criteria D. References E. Existing Conditions F. Proposed Conditions G. Downstream Analysis H. Stormwater Quality Section 11: Appendix A. Site Information B. Existing Conditions (Exhibits, Calculations, etc.) C. Proposed Conditions (Exhibits, Calculations, etc.) D. ICPR Input Data SECTION 1: REPORT A. Project Title Ashmoor Residential Subdivision - PUD (131st Street & Shelborne Road) B. Project Description This project is located on the southwest corner of the intersection of West 131st Street and Shelborne Road in the City of Carmel, Hamilton County, Indiana. The overall site is approximately 39.19 acres in size less existing right -of -way grants. The site is currently vacant and is used as agricultural farmland. The overall proposed development will be a 59 lot single family residential subdivision. These plans and calculations analyze the existing and proposed drainage patterns and will show that the proposed improvements will have no negative effect on drainage conditions in the area. The existing land uses adjacent to the subject site are as follows: North: Residential West: Residential South: Agricultural /Residential East: Residential C. Design Method and Criteria 1. Soil Type: Soil maps from the United States Department of Agriculture, Soil Conservation Service, identify Crosby Silt Loam (CrA - 52% Site) Type "C" Soil, and Brookston Silty Clay Loam (Br - 48% Site) Type "B" Soil. 2. Design Storm: The 2, 10 and 100 -year storm events have been analyzed for both the existing and proposed overall conditions. Hydraulics / Hydrology and detention sizing was performed using the SCS -II 24 hour rainfall distribution. 3. Overall Watershed: Boone Creek. D. References 1. TR55 Stormwater Design Manual. 2. Hamilton County Soil Survey. 3. Highway Extension and Research Project for Indiana Counties (HERPIC). E. Existing Conditions The existing property drains via overland flow to the southwest to an existing 24" RCP storm sewer constructed as part of Shelbourne Estates. The entire subject property is part of the Albert Shaw watershed which drains southwest ultimately outletting into Boone Creek. The site is vacant and is used as agricultural farm land currently planted with corn. A 24 -hour duration storm event was analyzed using the SCS -II rainfall distribution. Basin "EX1" represents the entire 39.59 acre site including the existing right -of -way to the centerline of the road of both 131st Street and Shelborne Road. Per the City of Carmel Stormwater Technical Standards Manual, we will be providing stormwater detention for the fully developed conditions of the right -of -way of both 131st Street and Shelborne Road. Therefore, the allowable release rate will be calculated based on the entire 39.59 acre site to the centerlines of both streets. The following table summarizes the existing runoff rates of the subject site as it exists today: Table 1: Existing Conditions Per the City of Carmel Stormwater Technical Standards Manual, the maximum allowable release rates in the fully developed condition shall be 0.10 cfs for a 10- year storm event and 0.30 cfs for a 100 -year storm event. Therefore, the allowable release rates for this site will be 3.96 cfs and 11.88 cfs for 10 -year and 100 -year storm events respectively. DRAINAGE BASIN RUNOFF (CFS) STORM EVENT 24 -Hour Event BASIN EX1 2 -YEAR 25.29 cfs 10 -YEAR 46.75 cfs 100 -YEAR 97.91 cfs Table 1: Existing Conditions Per the City of Carmel Stormwater Technical Standards Manual, the maximum allowable release rates in the fully developed condition shall be 0.10 cfs for a 10- year storm event and 0.30 cfs for a 100 -year storm event. Therefore, the allowable release rates for this site will be 3.96 cfs and 11.88 cfs for 10 -year and 100 -year storm events respectively. F. Proposed Conditions The proposed drainage patterns for the site will remain nearly identical to the existing conditions. A 2.38 +/- acre wet detention pond is being proposed along the western property line to provide stormwater detention and post- construction stormwater quality (BMPs). Per the City of Carmel Stormwater Technical Standards Manual, we are providing stormwater detention for the fully developed conditions of the right -of -way of both 131st Street and Shelborne Road. Basin "PR1" represents the entire 39.59 acre site including the fully developed proposed right -of -way to the centerline of the road of both 131St Street and Shelborne Road. The fully developed curve number was calculated to be 79.0; however, the City of Carmel Stormwater Technical Standards Manual requires that the actual curve number be downgraded to the next poorest classification. Therefore, this results in a downgraded curve number of 84.9 which is what was used in the hydraulic model. The following table identifies the release rates from the site, with the proposed improvements, AFTER being routed through the proposed detention facility. STORM EVENT DETENTION POND DISCHARGES (CFS) DETENTION POND STAGE 2 -YEAR 2.15 cfs 908.51' 10 -YEAR 3.77 cfs 909.25' 100 -YEAR 9.38 cfs 910.89' Table 2: Proposed Conditions Proposed 10 -year discharge 3.77 cfs < 3.96 cfs (allowable release at 0.1 cfs per acre for 39.59 acres) Proposed 100 -year discharge 9.38 cfs < 11.88 cfs (allowable release at 0.3 cfs per acre for 39.59 acres) G. Downstream Analysis An existing 24" RCP storm sewer constructed as part of Shelbourne Estates has been sized to accommodate the runoff from the proposed development. The storm sewer was constructed at 0.30% which has a calculated capacity of 12.39 cfs with zero head and 17.89 cfs with one foot of head. The maximum discharge from the proposed development during a 100 -year storm event will be 9.38 cfs; therefore, there is more than adequate capacity to accommodate the proposed development. H. Stormwater Quality A 2.38 +/- acre wet detention facility will be used to address the post- construction stormwater quality requirements. Per table 701 -1 of the City of Carmel Stormwater Technical Standards Manual, a wet pond (PC -110) will provide the required 80% TSS removal. Wetland plantings can also be added at the outlet points into the detention facility as an additional measure. SECTION 11: APPENDIX A. Site Information VICINITY MAP SCALE: 1" = 2,000' 0 NORTH B. Existing Conditions EXISTING CONDITIONS Impervious Area = Open Area = Row Crops = Runoff Curve Coefficient Number 0.90 98 0.20 67.8 0.50 81.6 * *Open Space (Good Condition) * *Straight Row (Good Condition) Crosby Silt Loam (CrA - 52% Site) Type "C" Soil Brookston Silty Clay Loam (Br - 48% Site) Type "B" Soil ON SITE (EX1) - Includes Existing Half R/W for 131st & Shelborne Impervious Area Open Area Row Crops Total Total Composite (ft ^2) (ft ^2) (ft ^2) (ft ^2) (Acres) "CN" 31200 35000 1658374 1724574 39.59 81.6 Allowable 10 -year Release Rate = 0.1 cfs / acre Allowable 10 -year Release Rate = 3.96 cfs Allowable 100 -year Release Rate = 0.3 cfs / acre Allowable 100 -year Release Rate = 11.88 Icfs Overland flow seg. 1 Shallow Concentrated Flow Basin name Length (ft) S % n T_t (min) Length (ft) S % Paved/Un (P or U) Vel. (ft/s) T_t (min) T_c (min) EX1 100 1.00 0.150 13 600 1.00 U 1.61 6 20 Allowable 10 -year Release Rate = 0.1 cfs / acre Allowable 10 -year Release Rate = 3.96 cfs Allowable 100 -year Release Rate = 0.3 cfs / acre Allowable 100 -year Release Rate = 11.88 Icfs Simulation Basin Group Time Max Flow Max Volume Volume hrs cfs in ft3 100YR -24HR EX1 PRE 12.09 181.18 4.364 627094 10YR -24HR EX1 PRE 12.09 84.97 2.024 290859 2YR -24HR EX1 PRE 12.09 45.09 1.092 156889 C. Proposed Conditions PROPOSED CONDITIONS Impervious Area = Open Area = Row Crops = Runoff Coefficient 0.90 0.20 0.50 Downgraded Curve Curve Number Number 98 98 67.8 77.1 81.6 87.1 Crosby Silt Loam (CrA - 52% Site) Type "C" Soil Brookston Silty Clay Loam (Br - 48% Site) Type "B" Soil "Open Space (Good Condition) "Straight Row (Good Condition) ON SITE (EX1) - Includes Fully Developed Half R/W for 131st & Shelborne Downgraded Impervious Area (ft^2) 640975 Open Area (ft ^2) 1083599 Row Crops (ft^2) 0 Total Total Composite Composite (ft^2) (Acres) "CN" "CN" 1724574 39.59 79.0 84.9 PROPSOED WET POND ELEV. AREA AREA Storage (ft.) (ftA2) (Acres) (acre -ft) 907.50 103860 2.3843 908 124686 2.8624 1.3117 909 132124 3.0331 2.9478 910 139662 3.2062 3.1197 911 147300 3.3815 3.2939 912 155037 3.5592 3.3827 913 162872 3.7390 3.5603 Storage = 17.616 acre -ft Overland flow seg. 1 Shallow Concentrated Flow Basin name Length (ft) S % n T_t (min) Length S (ft) % Paved/Un (P or U) Vel. (ft/s) T_t (min) T_c (min) PR1 (SEE STORM SEWER SPREADSHEET) 20 Max Time Max Warning Max Delta Max Surf Max Time Max Max Time Max Name Group Simulation Stage Stage Stage Stage Area Inflow Inflow Outflow Outflow hrs ft ft ft ft2 hrs cfs hrs cfs POND POST 100YR24HR 14.20 910.89 911.50 0.0050 146484 12.08 192.25 14.19 9.38 POND POST 10YR24HR 14.81 909.25 911.50 0.0050 134038 12.08 95.38 14.81 3.77 POND POST 2YR24HR 15.47 908.51 911.50 0.0050 128475 12.08 53.83 15.47 2.15 D. ICPR Input Data ___= Basins Name: EX1 Group: PRE Unit Hydrograph: Uh484 Rainfall File: Rainfall Amount(in): 0.000 Area(ac): 39.590 Curve Number: 81.60 DCIA( %): 0.00 Node: EX1 Status: Onsite Type: SCS Unit Hydrograph CN Peaking Factor: 484.0 Storm Duration(hrs): 0.00 Time of Conc(min): 20.00 Time Shift(hrs): 0.00 Max Allowable Q(cfs): 999999.000 Name: PR1 Group: POST Unit Hydrograph: Uh484 Rainfall File: Rainfall Amount(in): 0.000 Area(ac): 39.590 Curve Number: 84.90 DCIA( %): 0.00 Node: POND Status: Onsite Type: SCS Unit Hydrograph CN Peaking Factor: 484.0 Storm Duration(hrs): 0.00 Time of Conc(min): 20.00 Time Shift(hrs): 0.00 Max Allowable Q(cfs): 999999.000 ___= Nodes Name: BOUNDARY Group: POST Type: Time /Stage Time(hrs) 0.00 12.00 24.00 Stage(ft) 906.570 906.570 906.570 Base Flow(cfs): 0.000 Init Stage(ft): 906.570 Warn Stage(ft): 906.570 Name: POND Group: POST Type: Stage /Area Stage(ft) 907.500 908.000 909.000 910.000 911.000 912.000 913.000 Area(ac) 2.3843 2.8624 3.0331 3.2062 3.3815 3.5592 3.7390 Base Flow(cfs): 0.000 Init Stage(ft): 907.500 Warn Stage(ft): 911.500 Name: STR -102 Base Flow(cfs): 0.000 Group: POST Plunge Factor: 1.00 Type: Manhole, Flat Floor Init Stage(ft): 906.810 Warn Stage(ft): 912.000 Stage(ft) 906.810 912.000 Area(ac) 0.0003 0.0003 Name: STR -103 Base Flow(cfs): 0.000 Group: POST Plunge Factor: 1.00 Type: Manhole, Flat Floor Stage(ft) 907.320 913.000 Area(ac) 0.0003 0.0003 Init Stage(ft): 907.320 Warn Stage(ft): 913.000 ___= Pipes Name: 102 - BOUNDARY Group: POST UPSTREAM Geometry: Circular Span(in): 24.00 Rise(in): 24.00 Invert(ft): 906.810 Manning's N: 0.013000 Top Clip(in): 0.000 Bot Clip(in): 0.000 From Node: STR -102 To Node: BOUNDARY DOWNSTREAM Circular 24.00 24.00 906.700 0.013000 0.000 0.000 Upstream FHWA Inlet Edge Description: Circular Concrete: Square edge w/ headwall Downstream FHWA Inlet Edge Description: Circular Concrete: Square edge w/ headwall Length(ft): 54.00 Count: 1 Friction Equation: Automatic Solution Algorithm: Most Restrictive Flow: Both Entrance Loss Coef: 0.00 Exit Loss Coef: 1.00 Bend Loss Coef: 0.00 Outlet Ctrl Spec: Use dc or tw Inlet Ctrl Spec: Use dc Stabilizer Option: None Name: 103 -102 Group: POST UPSTREAM Geometry: Circular Span(in): 24.00 Rise(in): 24.00 Invert(ft): 907.320 Manning's N: 0.013000 Top Clip(in): 0.000 Bot Clip(in): 0.000 From Node: STR -103 To Node: STR -102 DOWNSTREAM Circular 24.00 24.00 906.910 0.013000 0.000 0.000 Upstream FHWA Inlet Edge Description: Circular Concrete: Square edge w/ headwall Downstream FHWA Inlet Edge Description: Circular Concrete: Square edge w/ headwall Length(ft): 210.00 Count: 1 Friction Equation: Automatic Solution Algorithm: Most Restrictive Flow: Both Entrance Loss Coef: 0.00 Exit Loss Coef: 1.00 Bend Loss Coef: 0.00 Outlet Ctrl Spec: Use dc or tw Inlet Ctrl Spec: Use dc Stabilizer Option: None ___= Drop Structures Name: OUTLET -104 From Node: POND Group: POST To Node: STR -103 UPSTREAM Geometry: Circular Span(in): 24.00 Rise(in): 24.00 Invert(ft): 907.500 Manning's N: 0.013000 Top Clip(in): 0.000 Bot Clip(in): 0.000 DOWNSTREAM Circular 24.00 24.00 907.420 0.013000 0.000 0.000 Upstream FHWA Inlet Edge Description: Circular Concrete: Square edge w/ headwall Downstream FHWA Inlet Edge Description: Circular Concrete: Square edge w/ headwall * ** Weir 1 of 2 for Drop Structure OUTLET -104 * ** Count: 1 Type: Vertical: Mavis Flow: Both Geometry: Rectangular Span(in): 12.00 Rise(in): 11.00 Length(ft): 42.00 Count: 1 Friction Equation: Automatic Solution Algorithm: Most Restrictive Flow: Both Entrance Loss Coef: 0.000 Exit Loss Coef: 1.000 Outlet Ctrl Spec: Use dc or tw Inlet Ctrl Spec: Use dc Solution Incs: 10 Bottom Clip(in): 0.000 Top Clip(in): 0.000 Weir Disc Coef: 3.200 Orifice Disc Coef: 0.600 Invert(ft): 907.500 Control Elev(ft): 907.500 * ** Weir 2 of 2 for Drop Structure OUTLET -104 * ** Count: 1 Type: Vertical: Mavis Flow: Both Geometry: Rectangular Span(in): 14.00 Rise(in): 8.00 Bottom Clip(in): 0.000 Top Clip(in): 0.000 Weir Disc Coef: 3.200 Orifice Disc Coef: 0.600 Invert(ft): 909.250 Control Elev(ft): 909.250 TABLE TABLE ___= Hydrology Simulations Name: 100YR -24HR Filename: P: \BDX.003 - 131st and Shelbourne - Boomerang \Drainage \ICPR \100YR- 24HR.R32 Override Defaults: Yes Storm Duration(hrs): 24.00 Rainfall File: Scsii -24 Rainfall Amount(in): 6.46 Time(hrs) Print Inc(min) 30.000 5.00 Name: 10YR -24HR Filename: P: \BDX.003 - 131st and Shelbourne - Boomerang \Drainage \ICPR \10YR- 24HR.R32 Override Defaults: Yes Storm Duration(hrs): 24.00 Rainfall File: Scsii -24 Rainfall Amount(in): 3.83 Time(hrs) Print Inc(min) 30.000 5.00 Name: 2YR -24HR Filename: P: \BDX.003 - 131st and Shelbourne - Boomerang \Drainage \ICPR \2YR- 24HR.R32 Override Defaults: Yes Storm Duration(hrs): 24.00 Rainfall File: Scsii -24 Rainfall Amount(in): 2.66 Time(hrs) Print Inc(min) 30.000 5.00 ___= Routing Simulations Name: 100YR24HR Hydrology Sim: 100YR -24HR Filename: P: \BDX.003 - 131st and Shelbourne - Boomerang \Drainage \ICPR \100YR24HR.I32 Execute: Yes Alternative: No Restart: No Patch: No Max Delta Z(ft): 1.00 Time Step Optimizer: 10.000 Start Time(hrs): 0.000 Min Calc Time(sec): 0.5000 Boundary Stages: Time(hrs) Print Inc(min) 25.000 5.000 Group Run POST Yes PRE Yes Delta Z Factor: 0.00500 End Time(hrs): 25.00 Max Calc Time(sec): 60.0000 Boundary Flows: Name: 10YR24HR Hydrology Sim: 10YR -24HR Filename: P: \BDX.003 - 131st and Shelbourne - Boomerang \Drainage \ICPR \10YR24HR.I32 Execute: Yes Alternative: No Restart: No Patch: No Max Delta Z(ft): 1.00 Time Step Optimizer: 10.000 Start Time(hrs): 0.000 Min Calc Time(sec): 0.5000 Boundary Stages: Time(hrs) Print Inc(min) 25.000 5.000 Group Run POST Yes PRE Yes Delta Z Factor: 0.00500 End Time(hrs): 25.00 Max Calc Time(sec): 60.0000 Boundary Flows: Name: 2YR24HR Hydrology Sim: 2YR -24HR Filename: P: \BDX.003 - 131st and Shelbourne - Boomerang \Drainage \ICPR \2YR24HR.I32 Execute: Yes Alternative: No Restart: No Patch: No Max Delta Z(ft): 1.00 Time Step Optimizer: 10.000 Start Time(hrs): 0.000 Min Calc Time(sec): 0.5000 Boundary Stages: Time(hrs) Print Inc(min) 25.000 5.000 Group Run POST Yes PRE Yes Delta Z Factor: 0.00500 End Time(hrs): 25.00 Max Calc Time(sec): 60.0000 Boundary Flows: