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Home My WebLink AboutStudies APPLICANT 3/2/2023DEVELOPMENT AND PUBLIC WORKS SPRINGFIELD 225 FIFTH STREET OREGON SPRINGFIELD, OR 97477 PHONE: 541.726.3753 FAX: 541.726.1021 www.springfiald-or.gov STORMWATER MANAGEMENT SYSTEM SCOPE OF WORK (Area below this huefdled outbyApplica n) __— (Please return to Clayton A&Eamhern @ City ofSprb4gi2eld Development and Public Works, Fm # 736-1021, Phone # 736-1036), enwd:cnaeurlern@sprirtglleldor.gov Project Name: Paradigm Marcola Apartments Applicant: Matt Keenan, PE KPFF Engineers Assessors Parcel #: 1703251300800 Date: 01/10/2020 LandUse(s): Residential Phone#: 541.684.4902 Project Size (Acres): 4.7 Fax #: Approx. Impervious Area: 133,693 SF Email: 1703251300800 Project Description (Include a copy of Assessor's map): Project consist of construction of five new multi -family housing units, community center, drive aisle, associated parking and other amenities. Drainage Proposal (Public connedion(s), discharge location(s), etc. Attach additional sheet(s) if necessary: Storm runoff will be collected on-site via roof drains, downspouts, area drains and trapped catch basin. There is an existing 18" stub that will serve as the site connection point. The 18" stub is located Proposed Storrewater Best Management Practices: Storm runoff will potentially be treated with vegetated facilities (rain gardens, storm water planters) or a combination of vegetated facilities and mechanical tr atment. Additionally all catch basins within vehicle pavements will be tr ped for oil/ rease se aration. Areabelawahishne dledordb the C' mrdR edtatheA lk (At a nundimn5 all boats checked by the City on the front and bekkoftlds sheet shall be submitted or on application to be con Tete r subnuttal, akin h other irenwnb nay, be recess Mechanical treatment (such as catch basin ❑ Small Site Study — (use Rational Method for calculations) Ittillers) allowed for meeting pre treatment ❑ Mid -Level Development Study— (use unit Hydrograph Method for calcu -tins quiremenls, not allowed to meet the 50 "king lot treatment requirement ❑ Full DIainage Development Study- (use Unit Hydrogmph Method for calcula ions) Environmental Considerations: jrWellheadZone: 1 year totz ❑ Hillside Development: n/a ❑ Wedand/Riparian: n/a ❑ Floodway/Floodplain: n� ❑ Soil Type: ❑ Other Jurisdictions n/a Downstream Analysis: 8 N/A ❑ Flow line for starting water surface elevation: ❑ Design HGL to use for starting water surface elevation: ❑ Manhole/Junction to take analysis to: Return to Clayton McEachem @ City of Springfield, email: cmceachem@spdngfeAd-orgov, FAX., (541) 736-1021 COMPLETE STUDY ITEMS r Baredupon the tnfor nation provided on tie front ofdds sheet, the follou>ing represents a ndndnnou of uvh w it merkdfor on application to be complete for subnddal with respect to drainage; however, this list should not be used in lieu ofde Sprirgtield Development Cork (SDC) or the City's Engineering Design A3mma1. Connpltance with these requirements does not constitute site appromol, Adebooml site specific information nary be required Note: Upon scoping sheet subndttal, ensure completedfornu has been signed in the spare provickel below: Interim Design Standards/Water Quality (EDSPM Chapter 3 Req'd N/A 7 ❑ All non -building rooftop (NBR) impervious surfaces shall be pre-treated (e. g. multi-chambered catchbasinw/oil filtration media) for stonmvater quality. Additionally, aminimum of 50% of the NBR impervious surface shall be treated by vegetated methods. 7 ❑ Where required, vegetative stommwater design shall be consistent with design standards (EDSPM Section 3.02), set forth in Chapter 2 of the Eugene Stormrmer Management Manual. Z❑ For new NBR impervious area less than 15,000 square feet, a simplified design approach may be followed as specified by the Eugene Stomrmvater Management Manual (Sec2A.1). 0 ❑ If a stormrmer treatment Swale is proposed, submit calculations/specifications for sizing, velocity, flow, side slopes, bottom slope, and seed mix consistent with City of Springfield or Eugene's Stomrmvater Management Manual. Z❑ Water Quality calculations as required in Section 3.03.1 of the EDSPM. All building rooftop mounted equipment, or other fluid containing equipment located outside of the building, shall be provided with secondary containment or weather resistant enclosure. Z❑ 71 Drainage study prepared by a Professional Civil Engineer licensed in the state of Oregon. Z M A complete drainage study, as required in EDSPM Section 4.03.1, including a hydrological study map. Z❑ Calculations showing system capacity for a 2 -year stoma event and overflow effects of a 25 -year stoma event Private stommwater easements shall be clearly depicted on plans when private stommater flows from one property to The time of concentration (Tc) shall be determined using a 10 minute start time for developed basins. Review ofDownstream System EDSPM Section 4.03A.0 Z❑ A downstream drainage analysis as described in EDSPM Section 4.03A.C. On-site drainage shall be governed by the Oregon Plumbing Specialty Code (OPSC). Elevations of the HGL and flow lines for both city and private systems where applicable. ❑ n Design of Stoma Systems (EDSPM Section 4.04). ❑ ❑ Flow lines, slopes, rim elevations, pipe type and sizes clearly indicated on the plan set ❑ ❑ Minimum pipe cover shall be 15 inches for reinforced pipe and 36 inches for plain concrete and plastic pipe materials, or proper engineering calculations shall be provided when less. The cover shall be sufficient to support an 50,000 lb load without failure of the pipe structure. ❑ ❑ Manning's "n" values for pipes shall be consistent with Table 4-1 of the EDSP. All stoma pipes shall be designed to Other/Miscethmeous 71 ❑ Existing and proposed contours, located at one foot interval. Include spot elevations and site grades showing how site drains. ❑ Private stommwater easements shall be clearly depicted on plans when private stommater flows from one property to another. Z❑ Drywells shall not receive runoff from any surface w/o being treated by one or more BMPs, with the exception of residential building roofs (EDSP Section 3.03A A). Additional provisions apply to this as required by the DEQ. Refer to thewebsite: him/Avww.deo.state.or.ushvo/uic/uic.htm for more infomuation. Detention ponds shall be designed to limit runoff to pre -development rates for the 2 through 25 -year storm events. *Thisform simU be inchukd m nn Nhuhmen5 inside the frontcover, ofthe stormnsder shady. * IAWORTANT..- ENGINEER PLEASE READ BEEOWAND SIGN' As the engineer of record, I hereby certify the above required items are complete and included with the submitted stommater study and plan set. Signature Date Form Version 5: June 2015 FOR ASSESSMENT AND TAXATION ONLY vVV SEE MAP i 17032521 I' 11 c3'000000000000 � SW COR FELIX SCOTT DLC 51 1, 1 2700 I 1500 0i i 3AC 1 I' 1 1' 1 ,1 3 4 I 1 11 I 1 1 1 I' 11 'F• I' A 11 300 1' z, 1 11 I' 11 1 I' 1 Im I� 11 1 I 1 11 1 2900 z 1' 1 I� 1 a 1 S.W.1/4 N.E.1/4 SEC. 25 T.17S. R.3W. W.M. Lane County 1" = 100' 1501 3 3.9 AC 5.29998 a LOT "K 344 O NW COR �.B-POWERS---------- _-------- i DLC 81 ii 500 i - � 0.87A91' , a / —1 1 5.29008 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i - - - / +602 o / • J J 1 / U S=5/ i>,1 -- /%�� 4-_ _________1______ I o0 /P 702 700 i 701 1.43AC 4.49 AC 0.6 AC i i / i i / ' pce a / i' a i i / i ; e / i / / SE COR oLc so SEE MAP 17032512 1600 1 2.38 AC 1800 1.72 AC PCL.2 1 I I 1 1 1 I 1 1 1 i 1700 1.89 AC PCL.1 5.29811 9 529717 A m 5.34749 — — — — — — — — — — — — — -- SEE MAP 17032542 EUGENE -SPRINGFIELD HIGHWAY 1-105 1 0.1AC A7 3600 el 0.13 AC 76 3500 0.21 AC NIITIIAL s s 4142W.. 2700 1z0a5 1000 0i i 301 1300 0.34 AC 1 028 AC 1 2 3 4 I 1 3000�� I 1 1 1 0.1713 C 'F• 529008 A ? i 300 n z, 1 0.04 AC 11 1 _ 1 Im I� �ero',ee 1 I 1 3400 1 2900 z 0.18 AC- 1 1 ' 400 1 3s 0.14 AC 74 I' e9 f O NW COR �.B-POWERS---------- _-------- i DLC 81 ii 500 i - � 0.87A91' , a / —1 1 5.29008 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i - - - / +602 o / • J J 1 / U S=5/ i>,1 -- /%�� 4-_ _________1______ I o0 /P 702 700 i 701 1.43AC 4.49 AC 0.6 AC i i / i i / ' pce a / i' a i i / i ; e / i / / SE COR oLc so SEE MAP 17032512 1600 1 2.38 AC 1800 1.72 AC PCL.2 1 I I 1 1 1 I 1 1 1 i 1700 1.89 AC PCL.1 5.29811 9 529717 A m 5.34749 — — — — — — — — — — — — — -- SEE MAP 17032542 EUGENE -SPRINGFIELD HIGHWAY 1-105 1 0.1AC A7 3600 el 0.13 AC 76 3500 0.21 AC NIITIIAL s s ,•etl I __________ ________ 4142W.. 2700 1z0a5 1000 1101Q�T 1200 1300 0.34 AC 1 028 AC 1 2 3 4 I 1 3000�� I 1 1 1 0.1713 C 1 1 1 1 0.11 AC 1 1 SEE MAP I 170325111 I 1 _ 1 Im I� �ero',ee 1 I 1 3400 1 2900 1 0.18 AC- 1 0.18AC I 1 1 1 74 1 e9 f I 1 I 1 1 1 1 I 1 i ,•etl I __________ ________ \�, S 1100_____ 1 O.snc 1400 �. \1 027AC 28 .xe "ly1 24s 2600 60 ,m0 016ACA2300xp0]s721200 at2100a-00.14AC 2000012A e 4 F �' 0.121 " 2 3 a 2500 1 a n,enc 32 3 2700 1z0a5 1000 1101Q�T 1200 1300 0.34 AC Os8 AC 028 AC 1 pPo 2 3 4 3000�� C 0.1713 C k 0.11 AC COMMON ARA \�, S 1100_____ 1 O.snc 1400 �. \1 027AC 28 .xe "ly1 24s 2600 60 ,m0 016ACA2300xp0]s721200 at2100a-00.14AC 2000012A e 4 F �' 0.121 " 2 3 a 2500 1 a n,enc 32 3 2700 1z0a5 1200 0.14 AC 72 T1 e] w117 w',ve 3300 3000�� m. 0.1713 C k 0.11 AC COMMON ARA 0 2800E A 0.19AC _ �ero',ee 3400 2900 0.18 AC- 0.18AC ^F 74 e9 f 17032513 SPRINGFIELD LCATSKP- 2021-12-3009:08 CANCELLED 100 101 104 105 106 107 108 200 201 600 601 602 900 REVISIONS OL1&ID11- LCATIB,-CONVERT WP TO GIS 11.12-LCAT115- WN'R' STREET NTO TL 11M 12/30/2021-ICAT1M-LLABET MTL1101STL11W SPRINGFIELD 17032513 Preliminary Stormwater Report Marcola Apartments Prepared for: Paradigm Properties Prepared by: Mark Reyes, PE Project Engineer: Matt Keenan, PE February 2023 1 KPFF Project #2200316 KPFF'S COMMITMENT TO SUSTAINABILITY As a member of the US Green Building Council, a sustaining member of Oregon Natural Step, and a member of the Sustainable Products Purchasers Coalition, KPFF is committed to the practice of sustainable design and the use of sustainable materials in our work. When hardcopy reports are provided by KPFF, they are prepared using recycled and recyclable materials, reflecting KPFF's commitment to using sustainable practices and methods in all of our products. Table of Contents Project Overview and Description Project Size and Location ......... Existing vs. Proposed Condition. Project Narrative ........................... Proposed Stormwater System... Water Quality Facilitie Engineering Conclusions Tables and Figures Table 1: Pre -Development vs. Post -Development Flows ............................ Table 2: 24 -Hour Precipitation for Eugene, OR (NOAH Atlas 2, Volume X) Table 3: Catchment and Facility Table (See Exhibit 2, Appendix 1)............ Appendices Appendix 1 Basin Maps Appendix 2 Stormwater Plans Appendix 3 Existing Runoff Calculations Appendix 4 Proposed Runoff, Water Quality and Calculations Ma=Ia Apartments I KPFFC nsulting Engineers PRELIMINARYSTORMWATER REPORT Project Overview and Description Project Size and Location The Marcola Apartments project will be constructed on a 4.72 -acre site located along Marcola Road. The projectis bound by Marcola Road to the north, 22nd Street and residential development to the east, Highway 126 to the south and commercial and residential development to the west. The project development consists of six multi -family buildings. Watershed and Soil Description Springfield's stormwater basins are part of the larger Upper Willamette Basin. The site itself is located within the City of Springfield's West Springfield Q Street Basin, per the City's 2010 Stormwater Management Plan. The proposed stormwater system will connect to the City's stormwater system. The site has been identified as having type C and D soils. Soil types C and D have poor infiltration rates and no stormwater runoff will be infiltrated on site. Existing vs. Proposed Conditions Existing Conditions The site is currently an undeveloped grassy field with a few groupings of trees on the north half of the site. The site is relatively flat with site slopes generally in the 1 to 2 percent range. Grades across the site vary from 1 to 2 feet except for the berm located on the site's southern boundary. There are no existing stormwater facilities or current connections to any City public storm main. Proposed Conditions The proposed conditions will include six multi -family structures and a community center/gym. In addition, the development will include connecting drive aisles, sidewalks, covered and uncovered parking spots, a tennis court and a garage building. The project will treat site runoff according to City design standards Chapter 3 stormwater quality. Vehicle impervious surfaces will be treated with a combination of vegetated facilities and mechanical treatment (filters) with no more than 50 percent of the vehicle impervious area being treated through mechanical means. Additionally, catch basins within the vehicle areas will feature pre- treatment prior to conveying runoff to mechanical treatment. The site has been identified by the City as not needing detention. The proposed site includes 126,187 square feet of impervious area and 78,082 square feet of pervious area. Of the 125,822 square feet of impervious area, 56,615 square feet is from structures, 19,936 square feet is from pedestrian hardscape and 49,271 square feet is from vehicle pavement. Project Narrative The City of Springfield stormwater quality design criteria set forth in Chapter 4 calls for a water quality design storm of 0.83 inches in 24 hours rain event. Ma=Ia Apartments I RPFFC nsulting Engineers PRELIMINARYSTORMWATER REPORT Proposed Stormwater System The impervious area on-site is divided between the building roof areas, asphalt parking, asphalt drive aisles and site hardscape. See Appendix 1 for the drainage basin areas. Vegetative filtration facilities and mechanical treatment have been selected for water quality treatment. On- site new impervious surfaces from vehicle pavement such as drive aisles and parking spaces will be treated through a filtration planter or mechanical treatment structure. Per City design standards, no more than 50 percent of the vehicle pavement will be treated through mechanical treatment. All facilities will be designed per City of Springfield standards. The filtration planters will have open storage at the surface ranging from 8 to 12 inches deep with a minimum of 2 inches of freeboard. The planters will have 24 inches of growing media with landscaping planting for the water quality management. They will also have a minimum of 12 inches of rock storage depth below the facility. The filtration planters will treat the water quality storm and an overflow will collect larger storm events to convey to the stormwater system. The mechanical treatment will be a filter product such as BayFilter or Stormfilter. The product used will be sized in accordance with the manufacturer's recommendation. Table 1: Pre -Development vs. Poo -Development Flo e Development CFS CF CFS CF CFS CF CFS CF Existing Conditions Proposed Conditions Development Existing Conditions 0.01 261.356 0.35 4,745 0.44 5,869 0.53 7,022 0.34 5,446 2.20 28,057 2.55 32,696 2.90 37,322 CFS CF 0.63 8,196 CFS CF 0.71 9,148 Proposed Conditions 3.24 41,975 3.52 45,722 Water quality Facilities Basin 1 encompasses the buildings and the pedestrian hardscape not adjacent to the parking bays and drive aisle. Run-off from the buildings will be collected via roof drains and downspouts. Run-off from the pedestrian hardscape will be collected by area drains. The run-off will then be conveyed through the on-site storm drainage system and discharged into the City system at the main located in 22nd Street. Basin 2 encompasses the north section of the parking lot, drive aisle and the associated sidewalk adjected to the parking bays. The run-off will sheet flow north where it will be captured by two catch basins. These catch basins will filter and satisfy the pre-treatment requirement before sending run-off to a vault. The vault is where mechanical treatment via filtration (BayFilter, Storm Filter or approved equal) will take place. After treatment, run-off will be conveyed through the on-site storm system and discharge at the connection point Ma=Ia Apartments I RPFFConsulting Engineers PRELIMINARYSTORMWATER REPORT in 22nd Street. The treated vehicle pavement area is approximately 43 percent of the total vehicle pavement area. Basin 3 encompasses a portion of the parking bays, drive aisle and adjacent sidewalk located in the middle of the site. The run-off will sheet flow to the filtration planter located in the middle of the site via curb cut. The planter will provide treatment via filtration and overflow run-off will be routed to the on-site storm system via an overflow inlet. The treated run-off will be conveyed to the on-site stormwater system and then to the connection point in 22nd Street. Basin 3 encompasses a portion of the parking bays, drive aisle and adjacent sidewalk on the site's south side. The run-off will sheet flow to the filtration planter via curb cut. The planter will provide treatment via filtration and overflow run-off will be routed to the on-site storm system via an overflow inlet. The treated run-off will be conveyed to the on-site stormwater system and then to the connection point in 22nd Street. Flow Control Per the City of Springfield Stormwater Scoping sheet, no detention is required for the project site. Source Control Source control is required for facilities that are highly likely to generate pollutants that are not addressed through the implementation of vegetated stormwater facilities. There are a variety of trash areas located throughout the development that will require source control measures. To meet these requirements, heavy- duty sanitary drains located in the trash areas will be trapped, auto -primed, vented and connected to the sanitary sewer system. These drains will not convey to the storm drainage system. Additionally, trash areas will be covered and hydraulically isolated from the stormwater system. Analysis Water Quality Facilities The run-off for the impervious areas has been calculated and the planters and rain garden have been sized to meet or exceed the City of Springfield requirements. The calculations determine run-off using the Santa Barbara Urban Hydrograph (SBUH) Method and NRCS 24 -Hour Type IA Hyetograph as outlined Chapter 4 of the Engineering Design Standards and Procedures Manual. The facility capacity is based on the requirements and facility details found in City of Eugene Stormwater Design Manual. For analysis purposes, each basin required the following information as input data for the computer model: • Impervious Area (Ai), in acres • Curve Number (CNi), impervious • Travel Time (Tc) • Total Precipitation Ma=Ia Apartments I RPFFConsulting Engineers PRELIMINARYSTORMWAUR REPORT Precipitation data for the respective City of Springfield design storms are shown in Table 2 below. Table 2:24 -Hour Precipitation for Springfield, OR INOAA Atlas 2, Volume xl Bazin 1 Ped "'14'1A5 73,489 1.69 2-YearM4.3 Hardsrape 10-Year10UYear 8asin2 (Example) 26,931 0.62 2,243 0.05 29,174 MT -1 (Example) 13.686 031 -13.686 -0.31 Bldgs & Bazin 1 Ped "'14'1A5 73,489 1.69 136,634 Hardsrape 8asin2 (Example) 26,931 0.62 2,243 0.05 29,174 MT -1 (Example) 13.686 031 -13.686 -0.31 0 8asin4 (Example) 22,425 0.51 -22,425 I -0.51 0 FTP -2 To size each planter, the following information was needed: • Bottom area, in square feet • Bottom perimeter length or bottom width, in feet • Storage depth, in inches All the water quality facilities meet the City of Springfield water quality requirements. For full calculations and results, see Appendix 4. Engineering Conclusions Based on the Engineering Design Standards and Procedures Manual requirements, the facilities and conveyance components have enough capacity to handle the required storm events and should be approved as designed. 2200316 -kg Martola Apartments I UFFConsulting Engineers 5 PRELIMINARYSTORMWATER REPORT Appendix 1 Basin Maps Ma=Ia Apartmen4 I gPFFC nsul[ing Engineers PRELIMINARYSTORMWAUR REPORT 5 I I I T r._. J t s EXISTING AREA=205,565 SF 10"SS ° 10"55 10"55_ I J SHEET LEGEND - - PROPERTY �_____ UNE STORMWATE �.....L ............. ® EXISTING STORMWATER BASIN MAP 2 BASIN 4 AREA=23,962 SF IMPERVIOUS AREA=22,425 SF STORMWATER BASIN MAP Appendix 2 Stormwater Plans Ma=Ia Apartments I UFFC nsulting Engineers MELIMINARYSTORMWAUR REPORT CONNECT TO EXISTING 10" SANITARY LINE�r S Co -4 IE 10" IN=457.37 (E) S -10' PVC IE 6' IN457.37 (W) S - 6' PVC FIELD VERIFY POINT OF CONNECTION i 14.00' SANITARY i SEWER EASEMENT I I 10.00' EWEB WATER TRANSMISSION EASEMENT. EWES SHALL BE PRESENT WITH EXCAVATION OR INSTALLING UTILITIES WITHIN EWEB'S EASEMENT. COORDINATE WITH EWEB. 19:1 1. J O J m 0 101 -ss — 89 LF-15"SD— SO MH -1 RIM=465.90 IE 10" IN=460.14 (N) IE 10" IN=460.14 (S) IE 15" OUT=459.77 (E) FTP 1I► a II 97 LF -15' r'2 CONNECT TO EXISTING STORM STRUCTURE IE 15" IN=458.84 (W) IE IN=456.95 (N) EX. 60" IE IN=458.84 (E) EX 24" IE OUT=456.68 (S) EX. 72" FIELD VERIFY POINT OF CONNECTION NOT SURVEYED 0 UTILITY KEY NOTES NOTE DESCRIPTION DETAIL REF. 1 CONNECT TO EXISTING 10" SANITARY LINE. FIELD VERIFY PIPE SIZE, INVERT ELEVATION AND LOCATION. CONNECT TO EXISTING STORM STRUCTURE. FIELD VERIFY INVERT ELEVATIONS AND LOCATION. RESTORE 2 TRENCH PER CITY OF SPRINGFIELD STANDARDS. MILL AND OVERLAY 10 FEET BEYOND TRENCH IN EACH DIRECTION. TAP TO EXISTING 8" WATER MAIN. COORDINATE CONNECTION TO EXISTING MAIN WITH SUB. SUB TO PERFORM TAP, INSTALL FIRE PROTECTION TO 3 PROPERTY, AND INSTALL BOX AND METER. CONTRACTOR TO COORDINATE SCHEDULE AND EXACT LOCATION IN FIELD. CONTRACTOR TO POTHOLE PRIOR TO CONSTRUCTION. BWV BACKFLOW PREVENTION VAULT CB GIBSON STEEL CATCH BASIN WITH FLO-GUARD FILTERS FH FIRE HYDRANT FTP FLOW-THROUGH PLANTER WQ WATER QUALITY STRUCTURE II UTILITY CROSSING. PROVIDE 12" MIN. CLEARANCE, U.N.O. UTILITY LABEL LEGEND STRUCTURE LABEL FF"UTILITY TYPE ($D --STORM DRAINAGE) RUCTURE TYPE CALLOUT ID NUMBER (WHERE APPLICABLE) XX XX -XX X+XX.X RT X.X'—LOCATION (WHERE APPLICABLE) RIM= IE IN =XX.X^STRUCTURE INFO (WHERE APPLICABLE) IE OUT = XX.X PIPE LABEL UTILITY LENGTH UTILITY SIZE F—TFUTILITY TYPE XXLF-XX" XX S=X.XX% L__ SLOPE (WHERE APPLICABLE) SHEET LEGEND FP FIRE PROTECTION LINE S SANITARY SEWER LINE SD STORM WATER LINE W CF 1111191 14:441214 SCALE 1 INCH = 40 FEET 40 0 40 80 1Tff 800 Willamette Street, Suite 400 Eugene, OR 97401 0: 541.684.4902 F: 541.684.4909 w.W.koffcom 0 Paradigm 1 4 Revision Schedule No. Description I Date PRINT DATE THIS SET 3/01/2023 ISSUE DATES Pricing Pennit - Construction - Revision - Misc. - 11M DUSTRUD architecture 1622 Pearl Street Eugene, Oregon 97401 541.338.8544 d ustru darc hitecture. com m o m ry � N CONY, Fj 02 0 c m^ d a c a o m w 1o`o'md 03« I c L>15 E c0! a E$ n Q NEqpV $rnmono O w E 8 5 E0 0 0 `n m 5 o a E m d c w E m E$F �aSn DRAWN BY: FU CHECKED BY: MR 0 O U � A' 0 W � �a SHEET TITLE UTILITY PLAN SHEET NO. C-200 Appendix 3 Existing Runoff Calculations Ma=Ia Apartments I gPFFC nsulting Engineers PRELIMINARYSTORMWAUR REPORT SBUH Calculation Worksheet for City of Springfield Storm Events k l j j Project Name: Marcola Apartments Date: 1/26/2023 Designer: MAR Basin: Ex. 1 User -Supplied Data Pervious Area Impervbus Area Pervious Area, SF Pervious Area, Acres Pervious Area Cu rve Num her, CNpery Time of Con centratinn, TQ minutes 30,893 Impervious Area, SF Impervious Area, Acres 0.00 I mpervious Area Cu rve Nu mher, CN imp 98 Note: minimum Tc isfive minutes 0.71 85 5 CIN of Eugene 24Hour Rainfall Depths (NRCS Type 1Adlstrlbutlon) Recurrence Interval WQ 1 2 1 5 30 1 25 50 1 100 Inches 1 0.83 1 3.3 1 3.8 1 4.3 1 4.8 1 1 5.2 Calculated Data l Project Area, Acres 0]3 Total Project Area, Square Feet 30,893 urrence Interval WQ 2 5 10 25 50 100 k Flo. Rate, Qpeak, as I OA0.35OA0.53 —WQ 0.63 0.00 0.71 l RunoffVolume, V, cubic feet 26 4,745 5,86 7,022 8,196 0 9148e to Peak Runoff, hours 2A. 7.931 7331 7.83 783 0.00 7$3 Runoff Hydrogroph 0.80 —WQ —2 -Year 0.74 —S -Year —10 -Year 0.60 —25 -Year —50 -Year 0.50 —100 -Year 0.40 e 7 rc 0.30 0.20 0.10 0.08 0 500 1000 1500 2000 2500 Time, mintMea 8[0Willamem,Su,t,5uu,4O Eugen,()R ] 1 511.f$4.4902 kpff. m Appendix 4 Proposed Runoff, Water Quality and Calculations Ma=Ia Apartments I UFFC nsulting Engineers MELIMINARYSTORMWAUR REPORT SBUH Calculation Worksheet for City of Springfield Storm Events kpff Project Name: Marcola Apartments Date: 1/26/2023 Designer: MAR Basin:1 User -Supplied Data PerviousArea Im ervbus Area Pervious Area, SF Pervious Area, Acres Pervious Area Cu rve Num ber, CNpery Time of Con centratir Ta, minutes Impervious Area, SF 48,695 Impervious Area, Acres 1.12 I mpervious Area Cu rve No miner, CN imp 98 Note: minimum Tc isfive minutes 0.00 90 5 oru 4ur Rainfall Depths NRC6Trip bne —WQ Total Project Area, Square Feet 4$695 erfeEnceIt WQ 2 -Yr I 51r I 10 -Yr 1 25 -Yr 1 50 -Yr 1 100 -Yr Inches 1 0.83 1 3.3 1 3.8 1 4.3 1 4.8 1 1 5.2 Calculated Data Total Proj ect Area, Acres 1.121 —WQ Total Project Area, Square Feet 4$695 Recurrence Interval WQ 2 Y 5 -Yr 10 -Yr 25 -Yr 50 -Yr 10D -Yr Peak Flo. Rate, Qpeak, cis Ru noff Vol ume, V, cu bic feet Time to Peak Runoff, hours 0.20 0.96 1.11 1.26 SAS 0.00 1.53Total 2,544 12,446 14,46 16,493 18,518 0 20,139 783 7.83 783 7.83 783 0.00 7$3 Runoff Hydmgmph 1.80 —WQ —2 -Year 1.60 —5 -Year 1.40 —10 -Year —25 -Year 1.20 —50 -Year 100 —100 -Year V Zy g 0.80 K 0.60 0.40 0.20 0.00 0 500 1000 ism 2000 2500 Time, minxMe s 8WWilbmUeSr,tSuu,400 Eurn,O89]01 XL W09@ kpff. m SBUH Calculation Worksheet for City of Springfield Storm Events kpff Project Name: Marcola Date: 1/26/2023 Designer: MAR Basin:2 User -Supplied Data PerviousArea InnipentiousArea Pervious Area, SF Pervious Area, Acres Pervious Area Curve Num ber,CNpery Time of Con centratir Ta, minutes Impervious Area, SF 26,931 Impervious Area, Acres 0.62 Impervious Area Curve Number CNimp 98 Note: minimum Tc isfive minutes 0.00 90 5 CI of Eu ne 24Hour Rainfall Depths NRC6T eSAdlstrlbutbn —WQ Total Project Area, Square Feet RequrrenceI It WQ 2 -Yr I 51r I 10 -Yr 1 25 -Yr 1 50 -Yr 1 100 -Yr Inches 1 0.83 1 3.3 1 3.8 1 4.3 1 4.8 1 1 5.2 Calculated Data Total Project Area, Acres 0.621 —WQ Total Project Area, Square Feet 26,931 Recurrence Interval WQ I 2 -Yr I 5 -Yr I 10 -Yr I 25 -Yr I 50 -Yr I 100 -Yr Peak Flow Rate, Qpeak, cis 0.111 O.S31 0.611 0.70 0.7 O.ODI 085 Total Ru noff vol ume, V, cu bic feet 1,40 6,883 8,00 9,InJ 10,2421 01 11,138 Time to Peak Runoff, hours 783 7.83 783 7.83 783 0.1 783 Runoff Hydrogroph 0.90 —WQ —2 -Year 0.80 —S -Year 0.70 —10 -Year —25 -Year 0.69 —50 -Year 0.50 —100 -Year V Zy g 0.40 K 0.30 0.20 0.10 0.00 0 500 1000 ism 2DDO 2500 rrEe, n:nulea 80]Willa eru,Sr,tSuite4 Eurn,OP9]01 XL W09@ kpff. m SBUH Calculation Worksheet for City of Springfield Storm Events l J j j Project Name: Marcola Date: 1/26/2023 Designer: MAR Basin:3 User -Supplied Data PerviousArea InnipentiousArea Pervious Area, SF Pervious Area, Acres Pervious Area Curve Number, CNpery Time of Con centratir Tr, minutes Impervious Area, SF 13,686 Impervious Area, Acres 0.31 Impervious Area Curve Number CNimp 98 Note: minimum Tc isfive minutes 0.00 8o 5 CI of Eu ne 24Hour Rainfall Depths NRC6T eSAdlstrlbutbn —WQ Total Project Area, Square Feet 13,686 RequrrenceI It WQ 2 -Yr I 51r I 10 -Yr 1 25 -Yr 1 50 -Yr 1 100 -Yr Inches 1 0.83 1 3.3 1 3.8 1 4.3 1 4.8 1 1 5.2 Calculated Data Total Project Area, Acres 0.311 —WQ Total Project Area, Square Feet 13,686 Recurrence Interval WQ 1 2 Y I 5 -Yr I 17"_50 -Yr 10D -Yr Peak Flo. Rate, Qpeak, ch Total Runoff Volume,V, cubic feet Time to Peak Runoff, hours 0.06 0.27 031 0.35 OAO.ODI 0.40 OA3 735 3,4991 4,06 4,MSI 5,2051 01 5,660 7$3 7.83 7331 7.83 7$3 O.W1 7$3 Runoff Hydrogroph 0.50 —WQ —2 -Year 0.45 —5 -Year 0.40 —10 -Year 0.35 —25 -Year —50 -Year 0.30 —100 -Year C" V 0.25 L J K 0.20 0.15 0.10 0.05 0.00 0 500 1000 ism 2000 2500 rrEe, n:nulea 8WWHlam to Sr,tSuu,400 Eurn,O89]01 XL W09@ kpff. m Stormwater Facility Calculator Instructions: 1. Choose Facility Type 2. Choose shape 3. Complete information in highlighted cells Facility Planter Shape Amoeba Bottom Area: 262 sf Bottom Perimeter: 68 ft Vertical Sides 3,380 Storage Depth: MYrinrltration volume (co: Growing Media: �in 18 in Surface Storage Capacity 131 cf Infiltration Area 262 sf GM Infiltration Rate 2.5 in/hr Infiltration Capacity (avg) 0.015 cfs Results Below -Grade WATER QUALITY EVENT PASS ROCK CAPACITY N/A SURFACE CAPACITY 62% Recurrance Peak Flow Interval (cfs) Volume (cf) Rock Capacity Meets Infiltration? WQ 0.0152 634 N/A Filtration Only 2 -Yr 0.2701 3,380 N/A MYrinrltration volume (co: 5 -Yr 0.3125 3,947 N/A 10 -Yr 0.3548 4,506 N/A N/A 25 -Yr 0.3971 5,091 N/A 50 -Yr 0.0000 0 N/A 100-Yrl 0.43081 5,541 N/A 1201 Oak Street, Suite 100 Eu,ene,01197401 541.664.4902 kpa.cum lqj f Proje Name: Marw6 Basin:3 Date: 1/26/2023 Impermeable Liner Water quality Event Surface Facility Modeling 0.0600 0.0500 0.0400 N u 0.0300 0 0 c Ic o.ozoo 0.0100 O.Wro ; I I� 0 500 1000 1500 Time, minutes kpff Project Name: Marcola l3asin:3 Date: 1/26/2023 I% Surface Inflow 0% --— Infiltration Capacity 0% Percolation to Subsurface 0% iOX --- Overflow Surface Capacity 0% 80% 90% 100% 2000 2500 800 Willamette Street, Suite 400 EWene,OR97401 541.684.4902 kpa.wm SBUH Calculation Worksheet for City of Springfield Storm Events kpff Project Name: Marcola Date: 1/26/2023 Designer: MAR Basin:4 User -Supplied Data PerviousArea InnipentiousArea Pervious Area, SF Pervious Area, Acres Pervious Area Curve Num ber,CNpery Time of Con centratir Ta, minutes Impervious Area, SF 22,425 Impervious Area, Acres 0.51 Impervious Area Curve Number CNimp 98 Note: minimum Tc isfive minutes 0.00 RO 5 CI of Eu ne 24Hour Rainfall Depths NRCST eSAdlstrlbutbn —WQ Total Project Area, Square Feet 22,429 RequrrenceI It WQ 2 -Yr I 51r I 10 -Yr 1 25 -Yr 1 50 -Yr 1 100 -Yr Inches 1 0.83 1 3.3 1 3.8 1 4.3 1 4.8 1 1 5.2 Calculated Data Total Project Area, Acres 0.51 —WQ Total Project Area, Square Feet 22,429 Recurrence Interval WQ 2 -Yr 5 -Yr 10 -Yr 25 -Yr 50 -Yr 10D -Yr Peak Flow Rate, Qpeak, cis 0.0 OA4 OSI O.SS 0.65 0.00 0.71 Total Ru noff Vol ume, V, cu bic feet 1,1] S,732 6, 7,595 8,528 0 9,274 Time to Peak Ru noff, hou rs ]$ 7.83 7331 7.931 7231 O.ODI 7$3 Runoff Hydrogroph 0.80 —WQ —2 -Year 0.70 —S -Year —10 -Year 0.60 —25 -Year 0.50 —50 -Year —100 -Year C" V 0.40 L J K 0.30 0.20 0.10 0.00 0 500 1000 ism 2000 2500 rrEe, n:nulea 80]Willa eru,Sr,tSuite4 Eurn,OP9]01 XL W09@ kpff. m Stormwater Facility Calculator Instructions: 1. Choose Facility Type 2. Choose shape 3. Complete information in highlighted cells Facility Planter Shape Amoeba Bottom Area: 293 sf Bottom Perimeter: 68 ft Vertical Sides 956 Storage Depth: 12 in Growing Media: 18 in Surface Storage Capacity 293 cf Infiltration Area 293 sf GM Infiltration Rate 2.5 in/hr Infiltration Capacity (avg) 0.017 cfs Results Below -Grade WATER QUALITY EVENT PASS ROCK CAPACITY N/A SURFACE CAPACITY 74% Recurrance Interval Peak Flow (cfs) Volume (cf) Rock Capacity Meets Infiltration? WQ 0.0170 956 N/A Filtration Only 2 -Yr 0.4425 5,461 N/A MYrinrltration volume (co: 5 -Yr 0.5120 6,396 N/A 10 -Yr 0.5814 7,313 N/A N/A 25 -Yr 0.6506 8,245 N/A 50 -Yr 0.0000 0 N/A 100-Yrl 0.70591 9,020 N/A 1201 Oak Street, Suite 100 Eu,ene,01197401 541.664.4902 kpa.cum lqj f Proje Name: Marwla 6asin:4 Date: 1/26/2023 Impermeable Liner kpff Project Name: Marcola Basin -4 Water quality Event Surface Facility Modeling Bate: 1/16/2023 0.1000 Iss Surface Inflow 0.0900 0% 0.0800 — —— Infiltration Capacity 0.0)00 IOX Percolation to Subsurface 0.0600 0% N 0.0500 10% --- Overflow 0 0.0400 iovc z 0.0300 —Surface Capacity '095 0.0 00 80% 0.0100 90% 0.0000 100% 0 500 1000 1500 2000 2500 Time, minutes Wa1nr nu.114 . Fmn1 A.1—fodn M.vinlinv 800 Willamette Street, Suite 400 EWene,OR97401 541.684.4902 kpa.wm