Loading...
HomeMy WebLinkAbout006 DrainageReport_DQ Bozeman_12062022Storm Water Report Dairy Queen Bozeman 3500 Jamboree Way Bozeman, MT 59718 Prepared for: Legends Studio Prepared by: 707 W. 2nd Avenue Spokane, WA 99201 Tele: (509) 455-4448 FAX: (509) 455-7492 DCI Job No.: #21042-0071 Date: October 6, 2023 The methods, descriptions, and design calculations shown in this design report conform to the Montana Post-Construction Storm Water BMP Design Guidance Manual, unless noted otherwise, and are under the jurisdiction of the City of Bozeman relative to the collection, treatment, and disposal of the stormwater runoff. This report has been prepared by the staff of DCI Engineers under the direction of the undersigned professional engineer whose stamp and signature appears hereon. Table of Contents Section Page 1.0 Introduction 1 2.0 Existing Site Conditions 1 3.0 Site Soils 1 4.0 Proposed Storm Water Design Concept 1 5.0 Proposed Drainage System and Basin Summary 2 6.0 Erosion Control Considerations 2 7.0 Operation and Maintenance 3 8.0 Summary/Conclusions 3 List of Tables 5-1 Tabular Summary of Storm Water Analysis 2 List of Appendices Appendix I Project Location Map Appendix II Basin Map Appendix III Stormwater Calculations Appendix IV Geotechnical Report 1 Basis of Design of Storm Water System 1.0 Introduction This report describes the storm water design for the construction of the proposed Dairy Queen project located at 3500 Jamboree Way, Bozeman, MT 59718. The scope of the project consists of an approximately 2,418-SF restaurant, asphalt pavement parking lot, concrete pavement, associated concrete curbing, sidewalk, bio-infiltration storm water treatment facilities, and associated site utilities (i.e., water, sewer, electrical, telecommunications and natural gas). The existing site is currently vacant. Design for the storm water system was completed in conformance with the Montana Post-Construction Storm Water BMP Design Guidance Manual (September 2017). Please reference Appendix I for a Project Location Map and Appendix II for the Post Development Basin Map. 2.0 Existing Site Conditions The project site is an approximate .93-acre lot, located in the Catron Crossing subdivision, with Jamboree Way bordering the site to the west, Taco Bell to the south and E Valley Center Rd to the east a tributary stream deriving from the East Gallatin River. The existing site is currently undeveloped, consists of various grasses, and generally slopes gradually from the south to the north. A high point exists near the south-central portion of the existing site, with slopes ranging from 1-4% throughout the site. Current conditions indicate that stormwater primarily infiltrates directly into the soil for smaller storm events and some stormwater may overland flow off-site to the north during larger storm events. 3.0 Site Soils A geotechnical investigation was performed for the proposed Dairy Queen site by Rawhide Engineering Inc. The Geotechnical Engineering Report, dated August 24, 2021, indicates that the on-site soil conditions generally consist of a layer of topsoil with vegetation extending to a depth of 1.0 foot below the existing surface. Beneath the topsoil layer, lean clay with sand to depths ranging from 3.0 to 3.5 feet below existing site grade was encountered. Under the fine-grained soil layer, gravel with sand to the depths explored to 8 feet below existing site grade was encountered. Groundwater level was found to be at 4.8 feet and 5.2 feet below existing grade. Turner loam was the soil type identified by the NRCS soil survey. Due to the lack of an infiltration rate given by the geotechnical report provided, it was estimated from the NRCS Soil Survey that the infiltration rate is 1in/hr., although the gravelly layer under the lean clay likely has greater infiltration capabilities. The geotechnical evaluation is included in Appendix IV of this report. 4.0 Proposed Storm Water Design Concept The proposed storm water design concept for this site was designed using the Montana Post- Construction Storm Water BMP Design Guidance Manual. Bio-infiltration swales are proposed for this site, which meets the requirement of retaining 100% of the Runoff Reduction Volume (RRV). RRV is the volume of storm water runoff generated from the first 0.5 inches of rainfall from a 24- hour storm preceded by 48 hours of no measurable precipitation. Impervious area factored into this calculation included the asphalt and concrete parking lot, concrete drive-thru aisle, and sidewalks. The bio-infiltration swales meet the removal requirements for total suspended solids, total petroleum hydrocarbons, metals, and phosphorus. The proposed building will route all roof runoff to the permeable pavers to the east of the building. Runoff from the sidewalk, parking lot, and drive aisles will sheet flow into swales through curb inlets. There will be three basins, each with bio-infiltration swales built on-site to infiltrate all storm water generated on site. 2 5.0 Proposed Drainage System and Basin Summary The following is a description of the site’s post-development drainage basin conditions. Please see the attached basin map in Appendix II. Basin A includes the bulk of the impervious surface area for the site. Storm water sheet flows across the site to curb inlets and to Swale A. Basin B includes some sidewalk and a portion of the drive-through aisle. Given the site constraints, an catch basin will be installed to route storm water from Basin B to Swale B via storm pipe. Basin C includes a small portion of sidewalk at the south side of the building. Swale C serves to capture this runoff, and to ensure positive drainage away from the proposed structure. Table 5-1 below summarizes the site conditions and runoff rates for each basin (10-year design storm). See Appendix III for the runoff calculations for each Basin. Table 5-1 Tabular Summary Storm Water Analysis Drainage Basin Storage Volume Required (CF) Storage Volume Provided (CF) Treatment Area Required (SF) Treatment Area Provided (SF) Basin A 312 345 624 690 Basin B 91 93 181 185 Basin C 11 12 11 16 *Table 5-1 above summarizes the site conditions and runoff rates for each basin. See Appendix III for the runoff calculations for all the basins. 6.0 Erosion Control Considerations An erosion and sediment control plan are included as part of this project. The Contractor is responsible for ensuring the use of proper erosion control and shall maintain such measures throughout construction, until all pertinent landscaping and permanent erosion control measures (i.e., grassed areas, paved surfaces) have been established. Maintenance shall include daily inspections and repair of the installed BMPs. The contractor shall also inspect all erosion control measures following each storm water event during construction or until permanent measures are established. Specific temporary measures that will be used during construction include the installation of silt fencing, construction entrances, and inlet protection. Silt fencing will be installed along the down gradient property lines, parallel with the existing ground contours, or perpendicular to the storm water runoff direction. Periodically, the temporary erosion control measures must be cleaned of debris and siltation. The contractor shall dispose of the materials so as not to damage any reclaimed areas or create other erosion problem areas. Upon direction by the City of Bozeman, Owner, or Engineer, the Contractor may also be required to clean the roadway of siltation or other debris that may occur along or at the construction entrances. 3 7.0 Operation and Maintenance The property owner is responsible for maintaining the proposed storm drain system. The owner shall inspect the facilities after any major storm event to ensure it is draining properly. 8.0 Summary/Conclusions The proposed storm water system for this project provides treatment and disposal of runoff as required by the Montana Post-Construction Storm Water BMP Design Guidance Manual. The storm water system proposed for this project is based solely on post-development conditions of this site. Appendix I Vicinity MapNProject Location Appendix II UGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASSWRS 09°42'29" E 133.17'S 08°43'54" E 12.99'N 39°09'48" W 91.88'JAMBOREE WAYL: 48.18'R: 152.00'Δ: 18°09'41"CB: S 30°02'55" ECH: 47.98'LOT 4LOT 6VALLEY CENTER ROADN 81°44'33" E 264.43'465746564657465746 5 6 46554654465346524651465146514651465246534654465546554656465746544653465246534654 465246534654465446554656465546554655 4651465246534654465546514651465246534654465546574657 4656S 77°45'11" W 326.74 'CP1SPIRAL CHORD BEARING & DISTANCE'SWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRRESTAURANT2418 SFFFE= 4657.00UGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASGASSWRS 09°42'29" E 133.17'S 08°43'54" E 12.99'N 39°09'48" W 91.88'JAMBOREE WAYL: 48.18'R: 152.00'Δ: 18°09'41"CB: S 30°02'55" ECH: 47.98'LOT 4LOT 6VALLEY CENTER ROADN 81°44'33" E 264.43'465746564657465746 5 6 46554654465346524651465146514651465246534654465546554656465746544653465246534654 465246534654465446554656465546554655 4651465246534654465546514651465246534654465546574657 4656S 77°45'11" W 326.74 'CP1SPIRAL CHORD BEARING & DISTANCE'SWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWRSWR707 W. 2ND AVENUESPOKANE, WASHINGTON 99201PHONE: (509) 455-4448 - FAX: (509) 455-7492WEBSITE: www.dci-engineers.comCIVIL / STRUCTURAL© 10/6/20233805 valley commons drivesuite #11bozeman, mt 59718406.556.6676 p406.556.5782 fwww.legendsstudio.comAMERICAN DAIRY QUEENMINNEAPOLIS, MN U.S.A.SHEET NUMBER:*REGISTERED U.S. PATENT OFFICE, AMERICAN DAIRYQUEEN CORPORATION. THIS DRAWING, IT'S DESIGNDETAIL AND INVENTION ARE THE PROPERTY OFAMERICAN DAIRY QUEEN INC. (ADQ) AND SHALL NOT BECOPIED IN ANY MANNER NOR DISCLOSED TO ANYOUTSIDE PARTY WITHOUT ADQ CONSENT.DRAWN, CHECKED, & APPROVED BY :ISSUE DATE:REVISION DATE:7-27-2022 - CITY PLANNING SUBMISSIONBUILDING TYPE:DAIRY QUEEN GRILL & CHILLCORE46 - NORTHWEST...............---10/6/2023CITY REVIEW 11DAIRY QUEEN - CATRON CROSSING CATRON CROSSING SUBDIVISION BOZEMAN, MT 3500 JAMBOREE WAY C1.3STORM WATERPLANBASIN ABASIN BBASIN CSWALE ASWALE BSWALE C Appendix III Stormwater Facilities and Retention Basin Design Date:9/27/2023 Job. No.:21-42-0071 Arch. Name:Legends Studio Project: City of Bozeman (See Project Location Map) Design Frequency:10 year Property Area:0.93 acres 1) where RRV:Runoff Reduction Volume (acre-ft) P:Water Quality Rainfall Depth (.5 inches) Rv:Dimensionless Runoff Coefficient, Rv = 0.05 +0.9(I) I:% Imperv. Cover Draining to the Facility, (Decimal Form) A:Site Drainage Area (acres) i.Basin A RRV 311.92 cubic ft RRV 0.0072 acre-ft P 0.5 inch Rv 0.67 I 0.69 A 0.255 acre Impervious Area: SF Acres 7700 0.18 Total Area: SF Acres 11120 0.26 ii.Basin B RRV 90.31 cubic ft RRV 0.0021 acre ft P 0.5 inch Rv 0.81 I 0.85 A 0.061 acre Bio-Infiltration Swale DQ Bozeman Description and Assumptions Determine Runoff Reduction Volume (RRV) Inputs for Finding A: Impervious Area: SF Acres 2260 0.05 Total Area: SF Acres 2670 0.06 iii.Basin C RRV 5.42 cubic ft RRV 0.0001 acre ft P 0.5 inch Rv 0.37 I 0.36 A 0.008 acre Impervious Area: SF Acres 125 0.00 Total Area: SF Acres 350 0.01 2) a. Dmax 36.00 Maximum Depth of the Infiltration Cell (in) i 1.00 Infiltration Rate (in/hr) td 72 Maximum Draw Down Time (hrs) Design D 6 in Design D 0.5 ft b. i.Basin A A 623.8 Infiltration Cell Bottom Area (ft^2) V 311.92 Infiltration Cell Volume (ft^3) D 0.5 Design Depth of Infiltration Cell (ft) ii.Basin B Determine Infiltration Cell Volume Maximum Basin Depth Dmax=(i/2)*td Infiltration Bed Area A=V/D Inputs for Finding A: Inputs for Finding A: A 180.6 Infiltration Cell Bottom Area (ft^2) V 90.31 Infiltration Cell Volume (ft^3) D 0.5 Design Depth of Infiltration Cell (ft) iii.Basin C A 10.8 Infiltration Cell Bottom Area (ft^2) V 5.42 Infiltration Cell Volume (ft^3) D 0.5 Design Depth of Infiltration Cell (ft) A=V/D A=V/D Appendix IV Soil Map—Gallatin County Area, Montana (DQ Bozeman) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/15/2021 Page 1 of 3506244050624505062460506247050624805062490506250050625105062520506244050624505062460506247050624805062490506250050625105062520494510494520494530494540494550494560494570494580494590494600494610494620494630494640494650 494510 494520 494530 494540 494550 494560 494570 494580 494590 494600 494610 494620 494630 494640 494650 45° 42' 58'' N 111° 4' 14'' W45° 42' 58'' N111° 4' 7'' W45° 42' 55'' N 111° 4' 14'' W45° 42' 55'' N 111° 4' 7'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84 0 30 60 120 180 Feet 0 10 20 40 60 Meters Map Scale: 1:682 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Gallatin County Area, Montana Survey Area Data: Version 25, Sep 2, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 3, 2009—Sep 1, 2016 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—Gallatin County Area, Montana (DQ Bozeman) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/15/2021 Page 2 of 3 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 57B Turner loam, 0 to 4 percent slopes 1.5 100.0% Totals for Area of Interest 1.5 100.0% Soil Map—Gallatin County Area, Montana DQ Bozeman Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/15/2021 Page 3 of 3 Gallatin County Area, Montana 57B—Turner loam, 0 to 4 percent slopes Map Unit Setting National map unit symbol: 56xd Elevation: 4,350 to 5,400 feet Mean annual precipitation: 15 to 19 inches Mean annual air temperature: 39 to 45 degrees F Frost-free period: 90 to 110 days Farmland classification: Prime farmland if irrigated Map Unit Composition Turner and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Turner Setting Landform:Stream terraces Down-slope shape:Linear Across-slope shape:Linear Parent material:Alluvium Typical profile A - 0 to 6 inches: loam Bt - 6 to 12 inches: clay loam Bk - 12 to 26 inches: clay loam 2C - 26 to 60 inches: very gravelly loamy sand Properties and qualities Slope:0 to 4 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.57 to 1.98 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water supply, 0 to 60 inches: Low (about 5.4 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Ecological site: R044BB032MT - Loamy (Lo) LRU 01 Subset B Hydric soil rating: No Map Unit Description: Turner loam, 0 to 4 percent slopes---Gallatin County Area, Montana DQ Bozeman Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/15/2021 Page 1 of 2 Minor Components Corbly Percent of map unit:5 percent Landform:Stream terraces, alluvial fans Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044BS354MT - Shallow to Gravel (SwGr) 15-19" p.z. Hydric soil rating: No Martinsdale Percent of map unit:5 percent Landform:Stream terraces, alluvial fans Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044BS355MT - Silty (Si) 15-19" p.z. Hydric soil rating: No Beaverton Percent of map unit:5 percent Landform:Stream terraces, alluvial fans Down-slope shape:Linear Across-slope shape:Linear Ecological site:R044BS354MT - Shallow to Gravel (SwGr) 15-19" p.z. Hydric soil rating: No Data Source Information Soil Survey Area: Gallatin County Area, Montana Survey Area Data: Version 25, Sep 2, 2021 Map Unit Description: Turner loam, 0 to 4 percent slopes---Gallatin County Area, Montana DQ Bozeman Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 11/15/2021 Page 2 of 2