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HomeMy WebLinkAboutStudies APPLICANT 12/14/2022Stormwater Management Plan and Drainage Study Brentwood Estates 317 30th Street Springfield, Oregon For Pat Bloom Countryside Partners Springfield, LLC 2571 California Park Dr., Suite 130 Chico CC: John Anderson The Satre Group 375 West 4", Suite 201 Eugene, OR, 97401 U #79232PE Nathx, aan..n'=""(a° A[,[y SIGNED OREGON "k � _ 9N PAT��-t� EXPIRES: 12/31/22 October 14th, 2022 ENGINEERING= Since 1977 civil - transportation structural • geotechnical SURVEYING w .Branch Engineering.com Contents 1. Introduction 2. Existing Conditions Page No. 1.1 Topography 1 1.2 Soils 1 1.3 Existing Storm System 1 3. Proposed Development.........................................................................................2 4. Stormwater Management 4.1 Stormwater Summary 4.2 Stormwater Analvsis S. Stormwater Compliance 5.1 Water Quality Treatment 5.2 Flow Control 6. MAINTENANCE 7. CONCLUSION Appendices Appendix A Stormwater Management Drainage Basin Map Appendix B Site Soils and Map Appendix C HydroCAD Analysis and Modeling Appendix D Site Infiltration Test Results and Location Map Appendix E Well Logs O Branch Fngineering, Inc Brentwood Estates, (22-226) ORober 14th, 2022 1. INTRODUCTION This Stormwater Management Plan (SWMP) report has been prepared for the analysis of constructing a new parldng lot at Brentwood Estates in Springfield. The subject site is east of 30- St., and the property is identified as Tax Map 17-02-31-00 Tax Lot 04700. Stormwater runoff from any new impervious area is proposed to be directed to onsite stormwater treatment and detention facilities. 2. EXISTING CONDITIONS The development area is located in Springfield, Oregon in the residential area east of 28m St. and north of Main St., and consists of 1.49 acres of private property. The slopes in the area range from 0.2- to 4.3 -percent with the low point on site being near the southwest corner of the lot. The existing area to be developed is currently a grass field with no existing structures. Per the well logs in Appendix I; the ground water is located approximately 14 -feet -deep near the site. 2.1 TOPOGRAPHY The portion of the propertydesignated for construction has no current development of any kind on it. There are no existing trees, landscaping, or other natural site restrictions. The site is fairly flat, and has no slopes greater than S% 2.2 SOILS The Natural Resources Conservation Service (NRCS) Web Soil Survey maps the subject site as containing one soil type: Coburg -Urban Land Complex (32). Coburg -Urban Land Complex is described as a loamy alluvium over a clayey alluvium and is in Hydrologic Soil Group C; the soil has a limiting drainage capacity between 0.20 and 0.57 inches per hour. The typical profile of the soil type has silty clay loam between 0-18 inches, silty clay from 18-53 inches, and fine sandy loam from 53-65 inches. A soils map and individual soil information is provided in Appendix B. An infiltration test was performed on September 12, 2022. The Site Infiltration Test Results in Appendix D found that the infiltration rate for the soils on site has a field-tested recommended value of 2.7-inches/hour. The Engineering Design Standards and Procedures Manual for City of Springfield states that a factor of safety of at least 2 must be used in conditions where a site must retain water. An infiltration rate of 1.3-inches/hour will be used to design the facility in Section 7.0 below. 2.3 EXISTING STORM SYSTEM Currently there is no stormwater infrastructure on site that is able to collect the runoff from the development area. The lot is mostly flat, and drains overland to a low spot along the southern property line before crossing the property to an existing stormwater channel. On the tax lot to the south there is a stormwater outfall along the eastern property line and an inlet pipe near the western property line. This inlet/outlet combination has created an open channel between them runnin east to west. The inlet pipe to the west carries stormwater further west to a larger open channel system, which connects to the greater public stormwater infrastructure system in the area. Brentwood Fsrares, (22-226) October 14th, 2022 3. PROPOSED DEVELOPMENT The new development primarily includes additional parking to serve the existing apartment complex, as well as new park amenities. Treatment is required per City of Springfield's standards on water quality regarding parking lots. Detention is required due to the destination for the runoff being overland flow across an adjacent lot 4. STORMWATER MANAGEMENT 4.1 STORMWATER SUMMARY Three 267 sq. ft. stormwater planters will be installed along the center of the new parking area. All quality as filtration facilities and will meet the stormwater management standard for water quality. Under these planters is a 140'x27'x2' layer of drain rock to store excess runoff beyond the water quality storm. This facility will be sized to increase storage capacity to match or reduce pre -developed runoff rates off of the site. According to the City of Eugene Stormwater Management Manual, Stormwater Planters "are walled vegetated surface reservoirs used to collect and treat stormwater runoff from impervious surfaces by allowing pollutants to settle and filter out as the water percolates through the vegetation and soil mediums before infiltrating into the ground below or being piped to its downstream destination. 4.2 STORMWATER ANALYSIS All stormwater calculations were determined using HydroCAD 10.00 modeling software. This program utilizes the Santa Barbara Unit Hydrograph hydraulic modeling method. All results of the analysis are included in Appendix C. 24 -Hour Rainfall depths are based on City of Springfield Engineering Design Standards & Procedures Manual, Chapter 4. The proposed basin was modeled as a single basin draining to a single facility, rather than three equal - sized planters. The following table displays some of the characteristics and results of the infiltration facilities during the two primary design storm events (Water Quality, & 25 Year Storm). Table 4: Infiltration Facility Properties Faciity Oontdbuting Be. p . VW Event 25 Year Ewnt ID Summary Basins El Ele Ele Depth Depth morlel� morlel� S i Storm Ranters Bi 473.5 475.00 474W 473.70 474.75 R1 Rock storage Bi 470.00 472.00 474.00 470.00 472.00 "The storm planters include an orifice overilowset above the water quality storm depth at elevation 473.75'. The HydroCAD analysis outputs can be found in Appendix C and will be discussed in more detail in the following sections. Brentwood Estates, (22-226) ORober 14th, 2022 5. STORMWATER COMPLIANCE 5.1 WATER QUALITY TREATMENT The stormwater facilities described above were designed to meet City of Springfield Stormwater Management requirements per section 3.02,3.03, 4.16 and 4.17. This section will briefly confirm that the treatment mechanisms are in fact meeting those requirements. From the hydraulic analysis in Appendix C and the notes from the previous section, the primary indicator for water quality compliance for the stormwater planters is to make sure the water quality storm infiltrates through the filtering media before reaching an orifice to the drain rock layer. As indicated in the HydroCAD model and the previous table, the water level in the planter stays below the orifice in the overflow structure during the water quality storm, indicating vegetated treatment for the water quality event. 5.2 FLOW CONTROL The facilities described above were sized in order to have post -developed runoff rates meet pre - developed runoff rates, which are minimal for this site due to the existing topographic grades. The drain rock was modeled to infiltrate into the sell at 1.3 inches/hour based on infiltration test results. The peak flow for the existing site for a 25 -year storm event resulted in 0.45 cis as displayed in Appendix C. The proposed construction for the site will consist of an increased impervious area. However, much of the storm water will be detained and infiltrated on site in the facilities previously described before it is routed off-site meeting existing drainage patterns. The peak flow for the proposed improvements for the site resulted in 0.31 cis. The proposed development runoff rate for the site is well below the pre -developed discharge rates, meeting flow control requirement The facilities will be maintained privately since it will receive water only from private improvements and will be constructed under a building permit. Maintenance will be per the City of Springfield's Engineering Design Standards and Procedures Manual, and will follow the given Facility Specific Operations and Maintenance plan Repairs to storm facilities shall be made in accordance with City of Springfield Public Works Department. CONCLUSION Three 267 sq. ft. storm planters with additional rock storage have been designed to meet both water quality standards and capacity standards as outlined in the City of Springffelds's Engineering Design Standards and Procedures Manual. This facilitywas designedusing HydroCAD 10.0 modeling software, and the given impervious area of the development. This will be a private facility, and therefore will need to be maintained according to the given Facility Specific Operation and Maintenance plan. /_\»:1►IQ KV90 Stormwater Management Drainage Basin Map a 0 •-•-'-'-'-'•'•'•'•'•'•'.!.!.!.!.!.!.s!.:.:.:.2.2; .o❖.o❖.•.o•.o❖.❖.00❖.•.00❖.❖.o! . .... .......................... IIS Ilii i " y Pill'' all of '� •=-����� • • _ 'i� i� i�s-.� '•'�'�'�'•' � ��� ski -i:: MENS ♦1 7.11. ►I — •�� �O����r1 1 _He.ei►e.Nu � � 0 ------- RA I ------------- At APPENDIX B Site Soils and Map M I19' M 211 N Sail Map—lane County Area, Oregon Pr Pr 9101 91N 91M] 91W 91B] 91PA 9119 9119 3 ft &a6:A lai6saPe (11"x 85') 9rH. W �5 b N a 5 is m 9 Aa l5 5a ta] ta] r� Ix �1n: 14� Maaaor CvmmwtlYala: Nk584 fdlge ES: UIMZme 1W 1W584 LiNatural Resources IM1Fb Sol Survey Conservation Service Nalmal Cooperative Scil Survey 9eN 96tl 9� 9K9 M•YSN q� y M•2 -N 9159 i 3 p 10/4/2022 Page 1 a 3 Soil Map—Lane County Area, Oregon _SD, Natural Resources web Sol Survey 10/42922 alaill Conservation Service National Cooperative Sail Survey Page 2 of 3 MAP LEGEND MAP INFORMATION Area at Wake. tA09 Spoil Area The sal surveys that comprise your AOI were mapped at Areaalnteresr(AQII Q army Spa 1:20,090. Soils Very Sony SpaWaming: Soil Map may not be valud al Mrs scale. 0 Soil Map Unit Polygons 9 VJrf S p a Enlargement of maps bethe scale of mapping can cause ,.,. Soil Map Unic Lines md Sell of the etail of mapping and accuracy of soil 4 Other line placement. The maps do not show the small areas of Map Unit Points contrasting soils that could have been shown at a more detailed Special Line FeaturesSoil Special Point Features scale. Lg Blowout water Features Streams and Canals Please rely on the bar scale on each map sheet for map ® Borrow Pit measurements. Trenspartatian Clay Spot Rails Source of Map: Natural Resources Conservation Service 0 Closed Depresdan Web Soil SurveyURL: Interstate Highways Coordinate System: web Mercator(EPSG:3B5]) Gravel Pit US Routes Maps from the Web Soil Survey are based on the Web Mercator Gravely Spa Major Roads projection, which preserves and shape but ion that schdistorts and area, projection that preserves area, such as the ® Landfill Local Roads Abersdistance o Albers equal-area conic projection, should be used if more Lava Flow accurate calculations of distance or area are req uired, Background aga Marsh or swamp . Aerial Photography This productis generated from the USDA4JRCS tended data as of Ne version date(s) listed below. .�. Mine or Query Soil Survey Area: Lane County Area, ® Miscellaneous Ydscer ep14,Oregon 2022 Survey Area Data: Version 20, Sep 14, 2022 ® Perennial VMmer Sail map units are labeled (as space allows) for map scales y, Rock Outcrop 1:50,099 or larger. A Saline Spot Dates) aerial images were photographed: Jun 12, 2019i 19, 2019 Sandy Spot The odhophoto or other base map on which the soil lines were Severely Eroded Spot compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor Sinkhole shifting ofmap unit boundaries may be evident, �p Slide or Slip Sodic Spot _SD, Natural Resources web Sol Survey 10/42922 alaill Conservation Service National Cooperative Sail Survey Page 2 of 3 Sal Map�ane Connly Area, Oregon Map Unit Legend LSIA Natural Resources Web Soil Survey 10/4/2022 i Conservation Serme National Cooperative Soil Survey Page 3 of3 Map Unit Symbd Map Unit Name Acres in AOI Pescara of AOI 32 Caburgi ffian land cornplex 1.5 100.0% Totals for Area ofinterest 1.5 100.0% LSIA Natural Resources Web Soil Survey 10/4/2022 i Conservation Serme National Cooperative Soil Survey Page 3 of3 Map Unit Description: Coburg -Urban land canplex--Lane Cmnty Area, Oregon Lane County Area, Oregon 32—Coburg-Urban land complex Map Unit Setting National map unit symbol. 2369 Elevation. 100 to 1,300 feet Mean annual precipitation: 30 to 60 inches Mean annual air temperature: 50 to 55 degrees F Frost -free period. 160 to 235 days Farmland classification. Farm land of statewide importance Map Unit Composition Coburg and similar soils: 55 percent Urban land. 30 percent Minor components: 4 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Coburg Setting Landform: Stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across -slope shape: Linear Parent material. Loamy alluvium over clayey alluvium Typical profile H1 - 0 to 18 inches. silty clay loam H2 - 18 to 53 inches: silty clay H3-53 to 65 inches: fine sandy loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Drainage class. Moderately well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to water table: About 18 to 30 inches Frequency of floodirg: None Frequency of ponding: None Available water supply, 0 to 60 inches. High (about 11.0 inches) Interpretive groups Land capability classification (irrigated): 2w Lard capability classification (nonirrigated): 2w Hydrologic Soil Group: C Ecological site: R002XCOO6OR -Stream Terrace Group Forage suitability group: Moderately Well Drained < 15% Slopes (G002XY0040R) LSM Natural Resources Wieb Soil Survey 10/4/2022 irk Conservation Serves National Cooperative Soil Survey Pagel oft Map Unit Description: Coburg -Urban land camplex--lane County Area, Oregon Other vegetative classification. Moderately Well Drained < 15% Slopes (G002XY0040R) Hydric sal rating. No Description of Urban Land Interpretive groups Lard capability classification (irrigated): None specified Lard capability classification (nonirrigated): 8 Hydric sal rating. No Minor Components Conser Percent of map unit: 4 percent Landform: Stream terraces Hydric sal rating: Yes Data Source Information Soil Survey Area: Lane County Area, Oregon Survey Area Data: Version 20, Sep 14, 2022 LSM Natural Resources Web Soil Survey 10/4/2022 211 Conservation Serves National Cooperative Soil Survey Page 2 ort APPENDIX C HydroCAD Analysis and Modeling EB1 Existing Basin ED1 Existing Ditch Subcat Reach On Link Routing Diagram for 22-226_Storm New 2022-1013 Prepared by (enter your tympany name here), Printed 10/13/2022 HydlmCAD®10.00-25 am 10]84 O 2019 Hydro AD Sd . Sd.Wns LLC 22-226 Storm New 2022-1013 Type IA 24 -hr 25 -yr Rainfall=4.80" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 2 Summary for Subcatchment EB1: Existing Basin Runoff = 0.45 cfs @ 7.99 hrs, Volume= 0.163 af, Depth= 2.72" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 -yr Rainfall=4.80" 31,355 80 31,355 80 100.00% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 10.0 Direct Entry, Summary for Reach ED1: Existing Ditch Inflow Area = 0.720 ac, 0.00% Impervious, Inflow Depth = 2.72" for 25 -yr event Inflow = 0.45 cfs @ 7.99 hrs, Volume= 0.163 of Outflow = 0.45 cfs @ 8.00 hrs, Volume= 0.163 af, Atten= 0%, Lag= 0.3 min Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs /2 Max. Velocity= 0.15 fps, Min. Travel Time= 0.6 min Avg. Velocity = 0.07 fps, Avg. Travel Time= 1.2 min Peak Storage= 15 cf @ 8.00 hrs Average Depth at Peak Storage= 0.12' Bank -Full Depth= 1.00' Flow Area= 25.0 sf, Capacity= 14.12 cfs 25.00' x 1.00' deep channel, n= 0.250 Length= 5.0' Slope= 0.0100 'f Inlet Invert= 473.80'. Outlet Invert= 473.75' B1 NEW Park g A New Storm Plant R1 New Storage [Lil Level Spreader Subcat Reach w Link 22-226 Storm New 2022-1013 Type lA 24 -hr 25 -yr Rainfall=4.80" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 2 Summary for Subcatchment 131: NEW Parking [49] Hint: Tc<2dt may require smaller dt Runoff = 0.79 cfs @ 7.90 hrs, Volume= 0.264 af, Depth= 4.40" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type IA 24 -hr 25 -yr Rainfall=4.80" /_RMIIFRii=6101 * 2,770 80 Landscape * 28,585 98 Parking and Sidewalk 31,355 96 Weighted Average 2,770 80 8.83% Pervious Area 28,585 98 91.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Reach L1: Level Spreader [90] Warning: Oout>Oin may require smaller dt or Finer Routing [87] Warning: Oscillations may require smaller dt or Finer Routing (severity=3) Inflow Area = 0.720 ac, 91.17% Impervious, Inflow Depth = 0.41" for 25 -yr event Inflow = 0.31 cfs 9.00 hrs, Volume= 0.025 of Outflow = 0.34 cfs 9.05 hrs, Volume= 0.025 af, Atten= 0%, Lag= 3.1 min Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Max. Velocity= 0.23 fps, Min. Travel Time= 0.2 min Avg. Velocity = 0.09 fps, Avg. Travel Time= 0.6 min Peak Storage= 5 cf @ 9.05 hrs Average Depth at Peak Storage= 0.10' Bank -Full Depth= 0.50' Flow Area= 8.8 sf, Capacity= 5.45 cfs 15.00' x 0.50' deep channel, n= 0.250 Side Slope Z -value= 5.0'f Top Width= 20.00' Length= 3.0' Slope= 0.0333 'f Inlet Invert= 473.80', Outlet Invert= 473.70' 22-226 Storm New 2022-1013 Type IA 24 -hr 25 -yr Rainfall=4.80" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 3 Summary for Pond 111: New Storage [78] Warning: Submerged Pond ST1 Primary device # 1 by 0.91' [80] Warning: Exceeded Pond ST1 by 0.27' 9.60 hrs (0.04 cfs 0.019 af) [80] Warning: Exceeded Pond ST1 by 0.27' 9.60 hrs (0.32 cfs 0.137 af) Inflow Area = 0.720 ac, 91.17% Impervious, Inflow Depth = 4.43" for 25 -yr event Inflow = 0.57 cfs 8.12 hrs, Volume= 0.266 of Outflow = 0.43 cfs 9.00 hrs, Volume= 0.266 af, Atten= 25%, Lag= 52.9 min Discarded = 0.11 cfs 5.75 hrs, Volume= 0.242 of Primary = 0.31 cfs 9.00 hrs, Volume= 0.025 of Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 474.41'@ 9.00 hrs Sud.Area= 3,789 sf Storage= 2,310 cf Plug -Flow detention time= 200.5 min calculated for 0.266 of (100% of inflow) Center -of -Mass det. time= 200.6 min ( 901.4 - 700.8 ) Volume Invert Avail.Storage Storage Description #1 470.00' 2,268 cf 27.00'W x 140.001 x 2.00'H Prismatoid 7,560 cf Overall x 30.0% Voids #2 470.00' 75 cf 2.00'D x 8.00'H Vertical Cone/Cvlinderx 3 2,343 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 470.00' 1.300 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 474.00' 6.0" Round Culvert L= 40.0' CMP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 474.00'/ 473.80' S= 0.0050'f Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf Discarded OutFlow Max=0.11 cfs @ 5.75 hrs HW=470.08' (Free Discharge) 1-1=Exfiltration (Exfiltration Controls 0.11 cfs) Primary OutFlow Max=0.31 cfs @ 9.00 hrs HW=474.41' TW=473.89' (Dynamic Tailwater) t2=Culvert (Barrel Controls 0.31 cfs @ 2.50 fps) Summary for Pond ST1: New Storm Planters Inflow Area = 0.720 ac, 91.17% Impervious, Inflow Depth = 4.40" for 25 -yr event Inflow = 0.79 cfs 7.90 hrs, Volume= 0.264 of Outflow = 0.57 cfs 8.12 hrs, Volume= 0.264 af, Atten= 27%, Lag= 13.1 min Primary = 0.04 cfs 1.60 hrs, Volume= 0.077 of Secondary= 0.54 cfs 8.12 hrs, Volume= 0.189 of Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 474.62'@ 8.12 hrs Sud.Area= 800 sf Storage= 898 cf Plug -Flow detention time= 38.2 min calculated for 0.264 of (100% of inflow) Center -of -Mass det. time= 38.2 min ( 701.8 - 663.5 ) 22-226 Storm New 2022-1013 Type IA 24-hr 25-yr Rainfall=4.80" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 4 Volume Invert Avail.Storage Storage Description #1 473.50' 1,200 cf 20.00'W x 40.001 x 1.50'H Prismatoid Device Routing Invert Outlet Devices #1 Primary 473.50' 2.000 in/hr Exfiltration over Surface area Phase-In= 0.01' #2 Secondary 473.75' 2.8" Vert. Orifice/Grate X 3.00 C= 0.600 #3 Secondary 474.80' 2.0' long x 2.00' rise Sharp-Crested Rectangular Weir X 3.00 2 End Contraction(s) 1.0' Crest Height rimary OutFlow Max=0.04 cfs @ 1.60 hrs HW=473.54' TW=470.00' (Dynamic Tailwater) =Exfiltration (Exfiltration Controls 0.04 cfs) ,Secondary OutFlow Max-0.54 cfs @ 8.12 hrs HW=474.62' TW=471.16' (Dynamic Tailwater) 2=Orifice/Grate (Orifice Controls 0.54 cfs @ 4.18 fps) 3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) 22-226 Storm New 2022-1013 Type lA 24 -hr WIQ Rainfall=0.83" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 5 Summary for Subcatchment 131: NEW Parking [49] Hint: Tc<2dt may require smaller dt Runoff = 0.11 cfs @ 7.93 hrs, Volume= 0.034 af, Depth= 0.58" Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-36.00 hrs, dt= 0.05 hrs Type IA 24 -hr WO Rainfall=0.83" /_RMIIFRii=6101 * 2,770 80 Landscape * 28,585 98 Parking and Sidewalk 31,355 96 Weighted Average 2,770 80 8.83% Pervious Area 28,585 98 91.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Reach L1: Level Spreader Inflow Area = 0.720 ac, 91.17% Impervious, Inflow Depth = 0.00" for WO event Inflow = 0.00 cfs 0.00 hrs, Volume= 0.000 of Outflow = 0.00 cfs 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Max. Velocity= 0.00 fps, Min. Travel Time= 0.0 min Avg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min Peak Storage= 0 cf @ 0.00 hrs Average Depth at Peak Storage= 0.00' Bank -Full Depth= 0.50' Flow Area= 8.8 sf, Capacity= 5.45 cfs 15.00' x 0.50' deep channel, n= 0.250 Side Slope Z -value= 5.0'f Top Width= 20.00' Length= 3.0' Slope= 0.0333 'f Inlet Invert= 473.80', Outlet Invert= 473.70' 22-226 Storm New 2022-1013 Type IA 24 -hr VVIQ Rainfall=0.83" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 6 Summary for Pond 111: New Storage Inflow Area = 0.720 ac, 91.17% Impervious, Inflow Depth = 0.58" for WO event Inflow = 0.04 cfs @ 7.70 hrs, Volume= 0.034 of Outflow = 0.04 cfs @ 8.10 hrs, Volume= 0.034 af, Atten= 0%, Lag= 24.0 min Discarded = 0.04 cfs @ 8.10 hrs, Volume= 0.034 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 470.00'@ 7.95 hrs Sud.Area= 3,789 sf Storage= 4 cf Plug -Flow detention time= 1.7 min calculated for 0.034 of (100% of inflow) Center -of -Mass det. time= 1.7 min ( 749.5 - 747.9 ) Volume Invert Avail.Storage Storage Description #1 470.00' 2,268 cf 27.00'W x 140.001 x 2.00'H Prismatoid #2 Primary 474.00' 7,560 cf Overall x 30.0% Voids #2 470.00' 75 cf 2.00'D x 8.00'H Vertical Cone/Cvlinderx 3 2,343 cf Total Available Storage Device Routing Invert Outlet Devices #1 Discarded 470.00' 1.300 in/hr Exfiltration over Surface area Phase -In= 0.01' #2 Primary 474.00' 6.0" Round Culvert Secondary= 0.00 cfs 0.00 hrs, Volume= 0.000 of L= 40.0' CMP, square edge headwall, Ke= 0.500 method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 473.70'@ Inlet / Outlet Invert= 474.00'/ 473.80' S= 0.0050'f Cc= 0.900 Sud.Area= 800 sf Storage= 156 cf n= 0.010 PVC, smooth interior, Flow Area= 0.20 sf Discarded OutFlow Max=0.04 cfs @ 8.10 hrs HW=470.00' (Free Discharge) t-1=Exfiltration (Exfiltration Controls 0.04 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=470.00' TW=473.80' (Dynamic Tailwater) t2=Culvert ( Controls 0.00 cfs) Summary for Pond ST1: New Storm Planters Inflow Area = 0.720 ac, 91.17% Impervious, Inflow Depth = 0.58" for WO event Inflow = 0.11 cfs 7.93 hrs, Volume= 0.034 of Outflow = 0.04 cfs 7.70 hrs, Volume= 0.034 af, Atten= 65%, Lag= 0.0 min Primary = 0.04 cfs 7.70 hrs, Volume= 0.034 of Secondary= 0.00 cfs 0.00 hrs, Volume= 0.000 of Routing by Dyn-Scor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.05 hrs / 2 Peak Elev= 473.70'@ 8.92 hrs Sud.Area= 800 sf Storage= 156 cf Plug -Flow detention time= 20.7 min calculated for 0.034 of (100% of inflow) Center -of -Mass det. time= 20.7 min ( 747.9 - 727.2 ) Volume Invert Avail.Storage Storage Description #1 473.50' 1,200 cf 20.00'W x 40.00'L x 1.50'H Prismatoid 22-226 Storm New 2022-1013 Type IA 24-hr VVQ Rainfall=0.83" Prepared by {enter your company name here) Printed 10/13/2022 HydroCAD® 10.00-25 sln 10784 © 2019 HydroCAD Software Solutions LLC Paae 7 Device Routing Invert Outlet Devices #1 Primary 473.50' 2.000 in/hr Exfiltration over Surface area Phase-In= 0.01' #2 Secondary 473.75' 2.8" Vert. Orifice/Grate X 3.00 C= 0.600 #3 Secondary 474.80' 2.0' long x 2.00' rise Sharp-Crested Rectangular Weir X 3.00 2 End Contraction(s) 1.0' Crest Height rimary OutFlow Max=0.04 cfs @ 7.70 hrs HW=473.54' TW=470.00' (Dynamic Tailwater) =Exfiltration (Exfiltration Controls 0.04 cfs) ,Secondary OutFlow Max=0.00 cfs @ 0.00 hrs HW=473.50' TW=470.00' (Dynamic Tailwater) 2=Orifice/Grate ( Controls 0.00 cfs) 3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Site Infiltration Test Results and Location Map anch ENGINEERING -- MITI civil . transportation structural• geotechnical SURVEYING 310 Sth Street SgtlngneN OR 97077 P: MNl 746 W3) www. Branch Eng l nee ring.com NCRE SITE PIAN PROrODED 9v CLIENT LEGEND Q I INFILTRATION TESTING LOCATION F-1NF,N . I - --•-•-•-•-• ... 1 -_ .:..... ......... ...... I-.-.-.-.-.-..-.-.-.-.-�:.............-.-.-.-.-.-.-.-.-.-.-... SCALE: NOTTOSCALE SITE EXPLORATION MAP - BRENTWOOD ESTATES FIGURE -1 31730TH ST. SPRINGFIELD, OREGON, 97478 10-10-7722 PROJECT NO. 22-226 anch #GINEER ING m Mflm Tex Rew isuq noaRrzRorzx ev mymxvmme rzarzm m T'ag utmw vwwc eeei �vmmmn � Tw t Tem�mW weemfW � OW a fW�W 0VM 1� 411 17 oos 1. m w- ew 'mrofmW zip 1 fmrtimN mNFl Ta m/eel 004 1� nualwu leve n n/mn n,leetw,le r,u ✓m. Well Logs OREGON 1241991 (1) OWNER/PROJECT: WELLNo. TP— L2 EM a— Nesti Resins 475 N. 28th Street na (2) TYPE OF WORK ® New oanstrueti. Repair ❑ Rerandidon ❑ au onion 0 Deeproing ❑ Aendaronent DRILLING METHOD ❑ Rotary Air Rotary Mud ❑ Cable ❑ Hollow Srem Auger ® Oi6er Backhoe (u) HURL HULL CUNS'1'KUC'1'1ON — no well install Yu No (Standards ❑ Depth of completed wen N/A R. —a TO — *—Fl. Seal —ft. TO _B. (5) WELL TEST: F]Pvmp E111dler ICES DEPT. Start Card# 27761 o(W —'J bCATIL ON OF WELL By legal descrip ion WellLoeafion: County 11WEB RESOURCES DEPT _ Towvship 17S (Nor S) R.%tjfW. DWGON Secd. 31 1. SW /4.f SW va of,bove section. 2 Street addrees of well location 765 N_ �8 h S rvr+ _ Springfield, OR 3. Ta, lot number of well lac,fion_ 27 0 0 4. ATTACH MAP WITH LOCATION IDENTIFIED. - -- (7) STATIC WATER LEVEL: 14 FL below lmdeyrf. Daze 09/05/91 _ Anesun PrusureI6/�q. m. Daze (8) WATER BEARING ZONES: Depthat which cant« was f., found __ From To &t. Flow Rete SWL 14 7 1 gprn (9) WELL LOG: diameter - int material Welded Threaded Glued mmmmm Liner diamete mazerid Welded Threaded Glued f ■ mawri,l interval(s): Fmm To Fmm To Slot siu m Mawrial S'm ❑ Air E] Rowing Artesim Conductiviry PI{ Temperature of water °F DepN maim Flow fond B. Wee wazer evelysie dmeT ®yes ❑ No By whom? Pacific Envimnman al ah _ Depth of srnta to be malyud. Fmm few ft. Name of supervising Due started 09/05/91 Gomplered 09/05/41 (.bonded) Monitor Well Corey , Cestitication: I certify tha the work I performedon the coe, n .a, altentio", or alsandonment of Nie well ie in wmpli"ncc with Oregon well mmwai. stnvdnrds. Materials usM and uSormazi. reponnd above are vueto Ne beat knowledge and Mid.. MWC Nombu (banded) Moniwr Well Coruwnor Cer iftwtion: I accept res sibility for the construction, alteration, or Amdavmrnt work performed. Nu well during the c.anretiou dates reporudabove. An work pedonnad during thio time is in compliance with Oregon well conshocfian a O,hod, ra W oche hnofmyknowledge and belie(. MWCNomberjp x-17 Ed•fifa�•'�.Tiii�iT�f'iiti5fi���4P/all Due started 09/05/91 Gomplered 09/05/41 (.bonded) Monitor Well Corey , Cestitication: I certify tha the work I performedon the coe, n .a, altentio", or alsandonment of Nie well ie in wmpli"ncc with Oregon well mmwai. stnvdnrds. Materials usM and uSormazi. reponnd above are vueto Ne beat knowledge and Mid.. MWC Nombu (banded) Moniwr Well Coruwnor Cer iftwtion: I accept res sibility for the construction, alteration, or Amdavmrnt work performed. Nu well during the c.anretiou dates reporudabove. An work pedonnad during thio time is in compliance with Oregon well conshocfian a O,hod, ra W oche hnofmyknowledge and belie(. MWCNomberjp x-17