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4 Prelim Stormwater Analysis Wallace
January 27, 2015 George Garcia garcia architecture + design 1308 monterey street, suite 230 san luis Obispo, ca 93401 Subject: the Monterey Hotel - Rainstore Alternative Location Dear George, As a result of site plan changes for the MONTEREY Hotel project that enclose the parking area, we have reviewed the request to relocate the underground Rainstore facilities outside of the building footprint (between the rear parking garage wall and the top of slope). The Rainstore sub-surface detention basin relocation is suitable. We can accommodate an equivalent volume for detention and retention storage to meet the City’s peak flow management criteria, and provisions for stormwater quality control necessary to satisfy the Construction General Permit. The drainage facilities located outside of the building footprint allows greater accessibility for future maintenance. Sincerely, Debra Tumler, PE SENIOR CIVIL ENGINEER C 55205 WALLACE GROUP | DEDICATION TO SERVICE® the MONTEREY PRELIMINARY STORMWATER CONTROL PLAN and BASIN ANALYSIS REPORT ADDENDUM Prepared for 1865 MONTEREY INVESTORS, LP San Luis Obispo, California Submitted by 612 Clarion Court San Luis Obispo, Ca 93401 T 805 544-4011 F 805 544-4294 Job Number: 1215.0001 April 9, 2014 CERTIFICATION Preparation of this report included efforts by the following persons: In accordance with the provisions of Section 6700 of the Business and Professions Code of the State of California, this report was prepared by or under the direction of the following Civil Engineer, licensed in the State of California: ENGINEER IN RESPONSIBLE CHARGE: 4/9/2014 Debra Tumler, PE 55205 (Lic. Exp. 6/30/14) Date Senior Civil Engineer DRAINAGE REPORT TABLE OF CONTENTS PROJECT STATISTICS .................................................................................................................. 1 SUMMARY ...................................................................................................................................... 1 SOILS .............................................................................................................................................. 2 HYDROGRAPH METHOD BASIN SIZING ANALYSIS ................................................................. 2 LOW IMPACT DEVELOPMENT STANDARDS ............................................................................. 4 LIST OF FIGURES Figure 1 – Project Site Plan .............................................................................................. 1 Figure 2 – NRCS Soils Survey Map & Data ...................................................................... 2 Figure 3 - Location of Sub-surface Detention Basin ......................................................... 3 Figure 4 – Detention Pond Hydrograph Design Output .................................................... 4 Figure 5 – Pervious Paver Driveway plan area providing infiltration ................................. 4 LIST OF TABLES Table 1 – Pre-project Site Runoff for All Storm Frequencies ............................................ 3 APPENDICES A. Stormwater Control Plan Application B. Existing & Developed Watershed Mapping C. Soils Survey Map & Soils Index D. Watershed Management Zone Diagram E. Hydrograph Method Basin Sizing Analysis F. Low Impact Development Volume Calculations the MONTEREY Hotel Development Page 1 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 PROJECT STATISTICS Requested Approvals Architectural Review & Administrative Use Permit, Environmental Review APN Number(s) ................................................................................................ 001-152-012 Land Use Category ............................................................................................ Commercial Zoning ......................................................................................................... C-T Commercial Property Location ................................................................................. 1845 Monterey Street Property Size ...................................................................................................... 1.93 acres Existing Parcels ................................................................................................................. 2 Proposed Parcels .............................................................................................................. 2 Property Owner ........................................... 1865 Monterey Street Investors, LP – Jess Parker SUMMARY This study has been prepared to determine the existing and proposed runoff conditions for developing the proposed facilities on the property. The project site is located within the San Luis Obispo (SLO) Creek watershed area. The Drainage Design Manual (DDM) of the Water Way Management Plan (WWMP) is the regulating document associated with development of the property. Figure 1 – Project Site Plan The City of San Luis Obispo has adopted new Post Construction Requirements for stormwater control. The Stormwater Control Plan application is prepared and can be found in Appendix A. Projects where Impervious Area >/= 22,000 SF and in Watershed Manangement Zone 1 shall meet Post Construction Requirements 1 – 4 as follows: 1. Site Design and Runoff Reduction, 2. Water Quality Treatment 3. Runoff Retention 4. Peak Management For the SLO City/WWMP drainage criteria to be accommodated, Special Floodplain Management Zone Regulations require the analysis to verify that there will be: the MONTEREY Hotel Development Page 2 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 No change in the 100, 50, 25, 10, 5 & 2 year peak flow runoff exiting the property Use of Best Management Practices (BMP’s) to minimize potential release of sediments and clarify storm flows in minor storm events to reduce pollutants moving downstream into San Luis Creek. City Standard Criteria for Source Control of Drainage and Erosion Control, page 7 and 8 Standard 1010 1. “Projects with pollution generating activities and sources must be designed to implement operation or source control measures consistent with recommendations from the California Stormwater Quality Association’s Best Management Practice Handbook, or equivalent” A map showing the existing watershed boundaries and proposed detention system is provided in Appendix B. SOILS The hydrologic soils groups for the tributary areas of the project are variable, but are predominately Los Osos-Diablo complex, 9 to 15 percent slopes - type C soils per the NRCS Soils Map, Figure 2. Figure 2 – NRCS Soils Survey Map & Data Additional description of the soil characteristics is available in Appendix C. HYDROGRAPH METHOD BASIN SIZING ANALYSIS For the proposed project, the development will construct a detention basin meeting San Luis Creek Water Way Management Plan (WWMP) Drainage Design Manual standards with a the MONTEREY Hotel Development Page 3 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 sub-surface Rainstore3 Pond System, vegetated areas, and pervious paved areas to control the required 95 percentile storm volume. Working with best management practices to deliver relatively clean storm runoff to the detention pond, the plan proposes to detain the peak developed runoff coming from the new improvements. This concept will in turn meet the Water Way Management Plan (WWMP) Drainage Design Manual standards to maintain pre-developed flow conditions for the 2, 5, 10, 25, 50 & 100 year storm events. Figure 3 - Location of Sub-surface Detention Basin Table 1 - pre-project site flow for the 1.08 acres of site to be disturbed is shown in the HydroCAD summary below: Table 1 – Pre-project Site Runoff for All Storm Frequencies the MONTEREY Hotel Development Page 4 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 These are the existing runoff peak flow (cfs) values that were used to analyze the detention basin size and the outflow structure design. The on-site detention pond is planned to be a sub-surface Rainstore3 System and holds 3’ of water depth during the 10 Year Storm Event with no overtopping of the proposed broad- crested weir structure. The hydrograph below shows the design parameters of the basin over a 24 hour period, and that the basin will be empty depending on the soil's percolation rate. Figure 4 – Detention Pond Hydrograph Design Output In larger storm events 25 – 100 Year recurrence intervals the detention pond controls the developed flow through the bleeder pipe and the broad-crested weir. The 100 Year maximum water surface elevation of 297.7 will be released at a rate of 3.2 cfs through both, and the top of the basin will be built at 298.7 to provide 1 foot of freeboard. A detailed report of the hydrograph analysis is provided in Appendix E. LOW IMPACT DEVELOPMENT STANDARDS The LID stormwater treatment requirements are to filter runoff from the developed site through structural BMP’s for low flow storm events. The design provides a series of pervious driveway and parking space cross-sections, landscaped areas planted with hearty rooted plant material and a Rainstore3 detention/retention pond to slow flows and encourage infiltration into a well-draining soil backfill. Figure 5 – Pervious Paver Driveway plan area providing infiltration (See full scale exhibit in Appendix B – Proposed Drainage Management Areas) the MONTEREY Hotel Development Page 5 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 The volumetric BMP’s are designed to meet the New Central Coast Regional Water Board, CCRWB PCR’s affective March 6, 2014, and adopted by the City of San Luis Obispo, which are for on-site Runoff Retention as specified in R3-2013-0032 Post Construction Storm Water Requirements, B.4.a and B.4.c.i.1) & 2). The 1.93 Acre site is within Water Management Zone, WMZ 1. The site consists of 0.93 acres of proposed impervious surface, 0.14 acres of pervious surfacing and landscape. This projects’s runoff retention requirement is to provide storage for the 95th Percentile 24-hour Rainfall depth equal to 2.08 inches, as taken from an isopoluvial map developed by the State Water Board for the site area. See an overlay of the project site on blow-up of this map in Appendix F. The calculation used the ASCE Manual of Practice No. 87 (1998) formula for computing a runoff coefficient based on i - the fraction of area tributary that is impervious, is as follows: C – 0.858i3 – 0.78 i2 + 0.774i + 0.04 Retention Volume 95th Percentile 24-hr Rainfall Depth = C x 1.95 x Area WMZ1 The volume is then calculated as a function of the Rainfall Depth, C and the Retention tributary area. The amount of on-site retention and bio-filtration treatment required for the MONTEREY site is 5,533 CF of storage. Figure 5 – Pervious Paver Driveway Section providing infiltration shows a typical structural BMP that will be used as a key part of the Storm Water Quality Plan for the hotel development. The bio-retention/filtration volume was managed in 1,507 CF of 14” deep crushed rock backfill below 3,228 SF of pervious paver driveway section, 400 CF of 8” deep rock backfill below pervious paver parking spaces and open-graded rock backfill beneath the detention pond 8” deep with a volume of 3,666 CF, all of which will flow laterally and naturally out to San Luis Creek. The detailed calculations for the bio-filtration areas can be found in Appendix F. This project is considered a Tier 3 Low Impact Development project as stated in the City of San Luis Obispo’s Stormwater Control Plan guidelines and application. As a Tier 3 LID project the site is required to implement at least two (2) LID measures for reducing on-site stormwater runoff. The development is incorporating the following structural water quality best management/volumetric practices: 1. Pervious paver driveway and parking spaces 2. Sub-surface bio-retention pond 3. Infiltration planters (north side of lobby) 4. Down-spout disconnection 5. Stormwater detention pond the MONTEREY Hotel Development Page 6 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 TECHNICAL APPENDIX TABLE OF CONTENTS A. Stormwater Control Plan Application B. Existing & Developed Watershed Mapping C. Soils Survey Map & Soils Index D. Watershed Management Zone Diagram E. Hydrograph Method Basin Sizing Analysis F. Low Impact Development Volume Calculations the MONTEREY Hotel Development Page 7 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 APPENDIX A STORMWATER CONTROL PLAN APPLICATION Stormwater Control Plan for Post Construction Requirements Application Submittal Where directions state “Done” that means no additional information or forms below that point needs to be filled out or furnished. See Exhibits for Watershed Management Zones, Basins, & Urban Sustainability Areas Use “n/a” where information requested is not applicable. If you are unsure regarding how to fill out any of the information, please come in and request assistance from a staff person. Project Information Step 1 Applicant Name: 1865 Monterey Street Investors, LP. Application No: 143‐13 Project Name: the MONTEREY Location Address: 1845 Monterey Street, San Luis Obispo, CA 93401 Location APN: 001‐152‐012 Site Zoning: C‐T Commercial Tourist Project Type: Commercial Detached Single Family Residential Industrial Multi‐unit Residential Mixed Use Public Project Phase: N/A Project Description: Redevelopment of a new multi‐story hotel with on‐site parking and retention of existing restaurant building. Total Project Site Area = 1.93 Acres Your project is NOT subject to Post Construction Requirements if… Step 2 Area (c) of project is < 2,500 square feet – Done OR Area (c) of project is > 2,500 square feet, and is a project type listed below ( type) – Done Road & parking surface repair – slurry & fog & crack seal, pothole & spot patching, overlay & resurfacing & other damage repair with no expansion Road & parking shoulder grading Road & parking cleaning, repairing, maintaining, reshaping, regarding drainage systems Sidewalk & bike path / lane project – no other impervious service created and runoff is directed to vegetated area Curb & gutter improvement or replacement – no other impervious created Underground utility project – surface replaced in kind Utility vaults – Ex: lift stations, backflows Fuel storage – above ground with spill containment Photovoltaic systems – on existing impervious surface, over pervious surface with vegetated cover, buffer strip at the most down gradient row of panels Second story – no increase in building footprint Decks & stairs & walkways – raised with space below for drainage Temporary structures – in place less than 6 months Otherwise, your project is subject to the Post Construction Requirements Project Site Details Step 3 Watershed Management Zone: WMZ #1 Stormwater Control Plan for Post Construction Requirements Urban Sustainability Area Name: N/A Meet USA Conditions Areas (a) Total New Impervious Surface Area = 0.93 ‐ 0.71 = 0.22 Acres (b) Total Replaced Impervious Surface Area = 24,698 SF, or 0.57 Acres (c) Total Existing Impervious Area = 30,850 SF, or 0.71 Acres (d) Total Impervious Area of Completed Project = 40,604 SF, or 0.93 Acres (e) Net Impervious Area: (a+b) – (c‐d) = OR where (c‐d) is a negative number: (a+b) = 0.22+0.57 = 0.79 Acres, or 34,412 SF > 22,000 SF See Area calculations in Step 3 to compare to thresholds in each Step below Where directions state “Go To”, fill out and attach the referenced Form and any supporting documents Step 4 Project is > 2,500 square feet Yes ‐ Go To Requirement 1 – Site Design & Runoff Reduction ‐ Form 1 AND THEN Go To Step 5 Step 5 Detached single family residential project where Area (e) is > 15,000 square feet OR Project where Area (e) > 5,000 square feet Yes ‐ Go To Requirement 2 – Water Quality Treatment ‐ Form 2 AND THEN Go To Step 6 No ‐ Done Step 6 Detached single family residential project where Area (e) > 15,000 square feet OR Project where Area (a+b) > 15,000 square feet AND is in Watershed Management Zone 4,7,10 over a ground water basin OR in Zone 1,2,5,6,8,9 Yes ‐ Go To Requirement 3 – Runoff Retention ‐ Form 3 AND THEN Go To Step 7 No ‐ Done Step 7 Project where Area (a+b) > 22,000 square feet AND is in Watershed Management Zone 1,2,3,6,9 Yes ‐ Go To Requirement 4 – Peak Management ‐ Form 4 No ‐ Done Exhibits 1. Watershed Management Zones 2. Groundwater Basin Location 3. Watershed Management Zone Revision Request (N/A) 4. Urban Sustainability Conditions and Maps of Approved Areas (N/A) Stormwater Control Plan for Post Construction Requirements Form 1 Requirement 1 – Site Design and Runoff Reduction: Identify the strategies used to reduce runoff through site design. Strategies 1‐5 required. Describe or attach simple plan details for 1. – 5. 1. Limit disturbance of creeks and natural drainage features and setback development from these features. Setbacks as required by the City of San Luis Obispo C/OS‐5 Existing Open Space documents. Flood control basin outlet pipe to be constructed to daylight with energy dissipation – above 100 Year Base Flood Elevation, BFE and outside of Biological Limit Line established by Natural Resources Manager on 5/29/2008. 2. Minimize compaction of highly permeable soils Existing parking spaces near creek to be replaced with permeable pavers and an 8” depth of open graded #57 rock backfill, and compaction of existing subgrade limited to the extent recommended by the Soils Report as feasible for supporting parked vehicles. 3. Minimize clearing of native vegetation and grading, conserving natural areas and maximizing undisturbed areas, and developing along natural landforms. Open space setbacks being held – construction of one 10” storm drain outlet pipe to meet the flood control detention requirements of the Waterway Management Drainage Design Manual for San Luis Creek. 4. Minimize impervious surfaces including roadways and parking lots Entry driveway and lobby parking spaces will be build using pervious pavers to minimize small storm flows running off onto the Monterey Street frontage. Providing a design that does not increase runoff onto existing infrastructure in any storm event 95 percentile depth, 2 Year – 100 Year storm events. 5. Other (Optional): Identify strategy(s) and describe or show how it will be done in the project. Large storm events above a 10 Year frequency will be controlled through a level spreader that will release over a 24’ wide span of pervious parking spaces and in a thin sheet flow manner that will be non‐erosive and move toward the creek bank having been filtered through the on‐site Rainstore3 pond and subsurface retention effective below the 10” SD Outlet 6. Do one of the following: Direct roof run off into cistern, rain barrel, or vegetated area Direct driveway and/or parking area into vegetated area Construct surfaces (bike lanes, walks, driveways, parking areas) with permeable surfaces StormwaterControlPlanforPostConstructionRequirements Form2 Requirement2 Ȃ WaterQualityTreatment: (ReferencePostConstructionStormwaterManagementRequirementsforDevelopmentProjectsintheCentral CoastRegion ʹ AdoptedJuly12,2013CaliforniaRegionalWaterQualityControlBoardCentralCoastRegion ʹ fordetailsregardingrequirements ʹ SectionB.3andSectionC.AlternativeCompliance.) Treatment Location OnSite OffSite AlternativeCompliance MeasureUsed 1.Harvesting,infiltration,evapotranspiration 2.Bio filtrationTreatment (Documentinabilitytouse1.) 3.Non RetentionBasedTreatment (Documentinabilitytouse1.or2.) Descriptionofstructuralcontrols: Inletcontrolboxwithdualchambersandweirstructuretoaidinsettlementandmaintenanceofsediments priortoentryintotheRainstore3pond. Alternativecompliancemeasures: Clickheretoentertext. Attachments Attachtreatment/sizingcalculations,includinganyvolumetreatedwithoff sitecompliance. Attachconstructionandplantingdetailsandspecificationsforbio filtrationoptions AttachdocumentationregardingTreatmentMeasureselection Attachinfeasibilityanalysiswherealternativecomplianceisproposed.(N/A) Certification IDebraTumlercertifythatthesystemsselectedandsized,asdemonstratedintheattachedcalculations,meet theWaterQualityTreatmentrequiredforthisprojectperthePostConstructionRequirementsadoptedbythe Central CoastRegionalWaterQualityControlBoard.Whereidentifiedintheattacheddocumentation,Water QualityTreatmentwillbemetthroughalternativecompliance. Signature Date Stormwater Control Plan for Post Construction Requirements Form 3 Requirement 3 – Runoff Retention: (Reference Post Construction Stormwater Management Requirements for Development Projects in the Central Coast Region – Adopted July 12, 2013 California Regional Water Quality Control Board Central Coast Region – for details regarding requirements – Section B.4 and Section C. Alternative Compliance.) If a revision to the site’s Watershed Management Zone is being requested, attach Watershed Management Revision Request Form (Exhibit) and supporting documentation. Rainfall maps are available from the Regional Water Quality Control Board Site Assessment Measures Summary Attach documentation of the following information: Site topography Development envelope Hydrologic features including natural areas, wetlands, watercourses, seeps, springs, and required setbacks Vegetative cover including trees Open space requirements Location of groundwater wells used for drinking water Depth to seasonal high groundwater Soil types and hydrologic soil groups Depth to impervious layer such as bedrock Presence of unique geology (e.g. karst) Geotechnical hazards Existing structures, utilities, and drainage infrastructure including municipal storm drain system components Existing easements and covenants Documented soil or groundwater contamination Source and estimated stormwater run‐on from offsite, coming to project area Drainage Management Areas (B.4.d.iii) Drainage management strategies by Drainage Management Area Runoff reduction measures and any structural control measures by Drainage Management Area (or full site as appropriate) Technical infeasibility limits on‐site compliance 10% of equivalent impervious surface area is dedicated to retention based stormwater control measures – No alternative compliance for retention Runoff volume ‐ compliance not achieved on‐site: Click here to enter text. Alternative compliance for retention proposed Runoff volume – compliance not achieved onsite: Click here to enter text. Runoff volume – alternative compliance used: Click here to enter text. Analysis and Sizing Attach calculated Tributary Areas and Design Volumes per the Post Construction Stormwater Management Requirements – Attachment D Adjustment made for redevelopment Adjustment made for being in, and meeting requirements of, an Urban Sustainability Area StormwaterControlPlanforPostConstructionRequirements Form3 ControlMechanism SiteinZone1,4,7,and/or10andovergroundwaterbasin 95th percentileeventretainedviainfiltration Findingoftechnicalinfeasibility ʹ StructuralStormwaterMeasureproposed SiteinZone2 95th percentileeventretainedviastorage,harvesting,infiltration,and/orevapotranspiration Findingoftechnicalinfeasibility ʹ StructuralStormwaterMeasureproposed SiteinZone5and/or8 85th percentileeventretainedviainfiltration Findingoftechnicalinfeasibility ʹ StructuralStormwaterMeasureproposed SiteinZone6and/or9 85th percentileeventretainedviastorage,harvesting,infiltration,and/orevapotranspiration Findingoftechnicalinfeasibility ʹ StructuralStormwaterMeasureproposed Attachments AttachAttachmentDcalculationsforhydrologicanalysisandstormwatercontrolmeasuresizing Attachdiscussionoftechnicalinfeasibilityforstructuralstormwatermeasure,whereproposedinlieuof preferredstorage,harvesting,infiltration,and/orevapotranspiration,includejustificationforanynon retentionbasedcontrols(N/A) Attachdocumentationoftechnicalinfeasibilityforon sitecompliance,includingasitespecifichydrologic and/ordesignanalysissupportingfindings(N/A) Attachdescriptionofalternativecomplianceprojectincludingasummarydescriptionofpollutantandflow reductioncomparingtheexpectedaggregateresultsofthealternateprojecttotheresultsthatwould otherwisehavebeenachievedbymeetingthenumericperformancerequirementsonsite.(N/A) AttachAttachmentEcalculationsforretentionrequirementadjustmentfortechnicalinfeasibility AttachAttachmentFcalculationsforoff siteretentionrequirements(N/A) Attachagreementforalternativecompliancesiteuse,forpurposesofachievingcompliance(N/A) AttachOperationsandMaintenancePlanforallstormwatercontrolmeasures(includeanyPeak Managementfacilities)tobedeliveredpriortooccupancy Post ConstructionOwnerIdentification Atthetimeofcompletionoftheconstructionwork,andtheshifttopost constructionstormwatercontrols, thebelowlistedownerisresponsibleforOperationsandMaintenanceofstormwatercontrolmeasures: 1865MontereyStreetInvestors,LP (Ifresponsibilitiesaredivided,listallresponsibleownersandassociatedmeasures.) Certification IDebraTumlercertifythatthesystemsselected,sized,anddesignedasdemonstratedintheattached calculations,meettheRunoffRetention PerformanceRequirementforthisprojectperthePostConstruction RequirementsadoptedbytheCentralCoastRegionalWaterQualityControlBoard.Whereidentifiedinthe attacheddocumentation,RunoffRetentionwillbemetthroughalternativecompliance. Signature Date StormwaterControlPlanforPostConstructionRequirements Form4 Requirement4 Ȃ PeakManagement (ReferencePostConstructionStormwaterManagementRequirementsforDevelopmentProjectsintheCentral CoastRegion ʹ AdoptedJuly12,2013CaliforniaRegionalWaterQualityControlBoardCentralCoastRegion ʹ fordetailsregardingrequirements ʹ SectionB.5 ) Showanystormwatercontrolmeasuresusedtomeettherequirementsofthissection,inthedocumentation andattachmentsrequiredforRetention (Form3),includinginallmappingandOperationsandMaintenance materials. PeakManagementCompliance Post developmentpeakflows,dischargedfromthesite,donotexceedpre projectpeakflowsforthe2 through10yearsstormevents. Technicalinfeasibilitylimitson sitecompliance Alternativecomplianceforretentionproposed Runoffvolume ʹ compliancenotachievedonsite:Clickheretoentertext. Runoffvolume ʹ alternativecomplianceused:Clickheretoentertext. Attachments Attachcalculationsshowingpre projectdischargeandpost projectdischargeforthe2through10year stormevents Attachdocumentationoftechnicalinfeasibilityforon sitecompliance,includingasitespecifichydrologic and/ordesignanalysissupportingfindings(N/A) Attachdescriptionofalternativecomplianceprojectincludingasummarydescriptionofpollutantandflow reductioncomparingtheexpectedaggregateresultsofthealternateprojecttotheresultsthatwould otherwisehavebeenachievedbymeetingthenumericperformancerequirementsonsite.(N/A) Attachagreementforalternativecompliancesiteuse,forpurposesofachievingcompliance(N/A) Post ConstructionOwnerIdentification Atthetimeofcompletionoftheconstructionwork,andtheshifttopost constructionstormwatercontrols, thebelowlistedownerisresponsibleforOperationsandMaintenanceofthepeakmanagementcontrol measures: 1865MontereyStreetInvestors,LP (Ifresponsibilitiesaredivided,listallresponsibleownersandassociatedmeasures.) Certification IDebraTumlercertifythatthesystemsselected,sized,anddesignedasdemonstratedintheattached calculations,meetthePeakManagementrequirementsforthisprojectperthePostConstruction RequirementsadoptedbytheCentralCoastRegionalWaterQualityControlBoard.Whereidentifiedinthe attacheddocumentation,PeakManagementwillbemetthroughalternativecompliance. Signature Date Stormwater Control Plan for Post Construction Requirements Exhibit 1 Watershed Management Zones the MONTEREY Hotel Development Page 16 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 APPENDIX B EXISTING & DEVELOPED WATERSHED MAPPING CO N S T R U C T I O N M A N A G E M E N T PU B L I C W O R K S A D M I N I S T R A T I O N ww w . w a l l a c e g r o u p . u s WA T E R R E S O U R C E S SU R V E Y I N G / G I S S O L U T I O N S LA N D S C A P E A R C H I T E C T U R E ME C H A N I C A L E N G I N E E R I N G PL A N N I N G ® the MONTEREY 1845 Monterey Street EXISTING DRAINAGE MANAGEMENT AREAS San Luis Obispo, California DM A EX 1 DMAEX 2 0 (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E (I N F E E T ) GR A P H I C S C A L E 40 80 1 I N = 4 0 F T 20 I /2 CONCRETE -IMPERVIOUS 892.4 SF 0.02 ACRES PERWOUS PAVERS 3228.4 SF 0.07 ACRES <= r =:>/ /1 PROPOSED ROOF/IMPERWOUS 4749.5 SF 0.11 ACRES RAINSTORE3 POND SYSTEM FLOOD CONTROL DETENTION + ON-SITE RUNOFF RETENTION STORAGE CAPACITY 6560 CF __ 1640 SF CONCRETE -IMPERVIOUS 35854.1 $F 0.82 ACRtS 24' LONG GRATED CHANNEL DRAIN ~TING AS LEVEL SPREA ER FOR 100 YEAR OVERFA OW OF POND SYSTEM PERVIOUS PAVERS 1504.0 SF 0.03 ACRES WALlACE GROUP® CIVILIINDTRAHSPCRTI'.TION ENCliNEERING CONSTRLICT10N MIINI'.QEMENT LANDSCN'E ARCHITEC'TURE MEOiANICAL ENGI~NG PlANNING PIJBUCWORI<Sl\DMINISTRIImN SURVEYING I QIS SOUJT10NS WA.lER RESOUMCE:S 612 CLARION COURT SAN LUIS OBISPO, CA 93401 T 805 544-4011 F 805 544-4294 -.wallacegroup.ue >-a; WCD 0:::.!::; w~ I-~ z.s oa ~~ Q)~ .c ..... - ~ ~ ..... z tU w ·-:::?! E w.e (!)= <( tU z u_ <( 0 :::?! g. w:c (!)Q <( 1/) z ·:; ~~ c tU 0(/} w CIJ ~ fE a.. JOB No. : 1215.01 DRAWING: DRT DRAWN BY: DRT DATE : 312512014 SCALE: 1" = 40' GRAPHIC SCALE 0 20 40 80 (IN FEET) 1 IN= 40FT the MONTEREY Hotel Development Page 19 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 APPENDIX C SOILS SURVEY MAP & SOILS INDEX All Ecological Sites -- Rangeland—San Luis Obispo County, California, Coastal Part (the MONTEREY) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2014 Page 1 of 3 39 0 7 5 3 0 39 0 7 5 5 0 39 0 7 5 7 0 39 0 7 5 9 0 39 0 7 6 1 0 39 0 7 6 3 0 39 0 7 6 5 0 39 0 7 5 3 0 39 0 7 5 5 0 39 0 7 5 7 0 39 0 7 5 9 0 39 0 7 6 1 0 39 0 7 6 3 0 39 0 7 6 5 0 39 0 7 6 7 0 713570 713590 713610 713630 713650 713670 713690 713710 713730 713750 713770 713570 713590 713610 713630 713650 713670 713690 713710 713730 713750 713770 713790 35° 17' 21'' N 12 0 ° 3 9 ' 5 ' ' W 35° 17' 21'' N 12 0 ° 3 8 ' 5 6 ' ' W 35° 17' 17'' N 12 0 ° 3 9 ' 5 ' ' W 35° 17' 17'' N 12 0 ° 3 8 ' 5 6 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 04590 180 270 Feet 0 15 30 60 90 Meters Map Scale: 1:1,020 if printed on A landscape (11" x 8.5") sheet. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons R014XD105CA R015XD049CA Not rated or not available Soil Rating Lines R014XD105CA R015XD049CA Not rated or not available Soil Rating Points R014XD105CA R015XD049CA Not rated or not available 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: http://websoilsurvey.nrcs.usda.gov 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: San Luis Obispo County, California, Coastal Part Survey Area Data: Version 5, Dec 14, 2013 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: May 8, 2010—May 21, 2010 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. All Ecological Sites -- Rangeland—San Luis Obispo County, California, Coastal Part (the MONTEREY) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2014 Page 2 of 3 All Ecological Sites — Rangeland San Luis Obispo County, California, Coastal Part Map unit symbol Map unit name Component name (percent) Ecological site Acres in AOI Percent of AOI 121 Concepcion loam, 5 to 9 percent slopes Concepcion (85%)R014XD105CA — LOAMY CLAYPAN 0.7 33.1% Cropley, clay (3%) Los Osos, loam (3%) San Simeon, sandy loam (3%) Tierra, loam (3%) 163 Los Osos-Diablo complex, 9 to 15 percent slopes Los Osos (35%)R015XD049CA — LOAMY CLAYPAN 1.4 66.9% Diablo (30%)R015XD001CA — CLAYEY Cibo, clay (9%) Lodo, clay loam (9%) Millsap, loam (9%) Unnamed (8%) Totals for Area of Interest 2.2 100.0% All Ecological Sites -- Rangeland—San Luis Obispo County, California, Coastal Part the MONTEREY Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2014 Page 3 of 3 References: Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service. U.S. Department of Agriculture Handbook 436. Soil Survey Staff. 2006. Keys to soil taxonomy. 10th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. Rating Options Aggregation Method: Percent Present Component Percent Cutoff: None Specified Tie-break Rule: Lower Hydric Rating by Map Unit—San Luis Obispo County, California, Coastal Part the MONTEREY Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2014 Page 5 of 5 the MONTEREY Hotel Development Page 26 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 APPENDIX D WATERSHED MANAGEMENT ZONE DIAGRAM CIVIL ENGINEERINGCONSTRUCTION MANAGEMENTLANDSCAPE ARCHITECTURE MECHANICAL ENGINEERING PLANNING PUBLIC WORKS ADMINISTRATION SURVEYING/GIS SOLUTIONS WATER RESOURCES WALLACE SWANSON INTERNATIONAL 612 CLARION COURT SAN LUIS OBISPO, CA 93401 T 805 544-4011 F 805 544-4294 www.wallacegroup.us WATERSHED MANAGEMENT ZONES for CENTRAL COAST REGION O 0 200 400100 Feet 1 inch = 200 feet Legend WMZs <all other values> WMZ_VALUE -99 1 10 2 3 4 4* 5 6 7 7* 8 9 AddressToParcel SLOCOCITY_LIMITS S_Wtr_Ln S_Fld_Haz_Ln 1845 MONTEREY PROJECT SITE the MONTEREY Hotel Development Page 29 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 APPENDIX E HYDROGRAPH METHOD BASIN SIZING ANALYSIS Cl o g g e d O u t l e t 18 4 5 M o n t e r e y S t Ex . D M A 2 18 4 5 M o n t e r e y S t R e s i d e n c e Ex . W S A ( d i s t u r b e d ) 18 4 5 M o n t e r e y S t r e e t ( d i s t u r b e d a r e a ) Pr o p D M A 2 th e M O N T E R E Y Pr o p ' d T r i b 18 4 5 M o n t e r e y S t 2PCB Le v e l S p r e a d e r B1 10 " S D O u t l e t Ro u t i n g D i a g r a m f o r _ _ 2 0 1 4 M a r c h _ 1 2 1 5 - 0 1 P r e l i m H y d Pr e p a r e d b y W A L L A C E G R O U P , P r i n t e d 3 / 3 1 / 2 0 1 4 Hy d r o C A D ® 1 0 . 0 0 s / n 0 6 2 7 6 © 2 0 1 2 H y d r o C A D S o f t w a r e S o l u t i o n s L L C Su b c a t Re a c h Po n d Li n k Type I 24-hr 100yr Rainfall=6.25"__2014March_1215-01 PrelimHyd Printed 3/28/2014Prepared by WALLACE GROUP HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Events for Subcatchment Ex. DMA 2: 1845 Monterey St Residence EventRunoff (cfs) Volume (cubic-feet) Depth (inches) 1in0.09 4390.50 1yr0.251,2081.39 2yr0.361,7371.99 5yr0.502,4282.79 10yr0.612,9903.43 25yr0.753,7274.28 50yr0.864,2784.91 95_0/0storm0.271,2821.47 100yr 0.964,8305.54 Type I 24-hr 100yr Rainfall=6.25"__2014March_1215-01 PrelimHyd Printed 3/28/2014Prepared by WALLACE GROUP HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Events for Subcatchment Prop DMA 2: the MONTEREY EventRunoff (cfs) Volume (cubic-feet) Depth (inches) 1in0.08 3840.50 1yr0.221,0571.39 2yr0.311,5201.99 5yr0.432,1242.79 10yr0.532,6163.43 25yr0.663,2614.28 50yr0.753,7434.91 95_0/0storm0.231,1221.47 100yr 0.844,2265.54 Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/1/2014Prepared by WALLACE GROUP HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Events for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) EventRunoff (cfs) Volume (cubic-feet) Depth (inches) 2yr1.477,1111.81 5yr2.1010,1502.59 10yr2.6012,6393.22 25yr3.2515,9174.06 50yr3.7318,3734.69 95_0/0storm1.065,1321.31 100yr 4.2120,8385.32 Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 3/31/2014Prepared by WALLACE GROUP HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Events for Pond B1: 10" SD Outlet EventInflow (cfs) Outflow (cfs) Discarded (cfs) Primary (cfs) Elevation (feet) Storage (cubic-feet) 2yr1.850.490.010.48297.064,015 5yr2.472.030.012.02297.304,377 10yr2.972.610.012.60297.414,548 25yr3.613.110.013.10297.534,731 50yr4.093.450.013.45297.634,877 95_0/0storm1.420.120.010.11296.953,851 100yr 4.573.790.013.78297.735,033 __2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 1HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Area Listing (selected nodes) Area (sq-ft) CNDescription (subcatchment-numbers) 1,56880>75% Grass cover, Good, HSG D (Prop'd Trib) 4,79294Newly graded area (Pervious only), HSG D (Prop'd Trib) 16,11780Pasture/grassland/range, Good, HSG D (Ex. WSA (disturbed)) 72,74598Paved parking, HSG D (Ex. WSA (disturbed), Prop'd Trib) 95,22294TOTAL AREA __2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 2HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Soil Listing (selected nodes) Area (sq-ft) Soil Group Subcatchment Numbers 0HSG A 0HSG B 0HSG C 95,222HSG DEx. WSA (disturbed), Prop'd Trib 0Other 95,222 TOTAL AREA __2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 3HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Ground Covers (selected nodes) HSG-A (sq-ft) HSG-B (sq-ft) HSG-C (sq-ft) HSG-D (sq-ft) Other (sq-ft) Total (sq-ft) Ground Cover Subcatchment Numbers 0 0 01,568 01,568>75% Grass cover, GoodProp'd Trib 0 0 04,792 04,792Newly graded area (Pervious only)Prop'd Trib 0 0 016,117 016,117Pasture/grassland/range, GoodEx. WSA (distur bed) 0 0 072,745 072,745Paved parking Ex. WSA (distur bed), Prop'd Trib 0 0 095,222 095,222TOTAL AREA __2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 4HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pipe Listing (selected nodes) Line#Node Number In-Invert (feet) Out-Invert (feet) Length (feet) Slope (ft/ft) nDiam/Width (inches) Height (inches) Inside-Fill (inches) 1B1294.80287.5048.00.15210.01010.00.00.0 Type I 24-hr 2yr Rainfall=2.63"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 5HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.02 hrs, 1801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=1.080 ac 65.74% Impervious Runoff Depth=1.81"Subcatchment Ex. WSA (disturbed): 1845 Monterey Street Tc=10.0 min CN=92 Runoff=1.47 cfs 7,111 cf Runoff Area=1.106 ac 86.80% Impervious Runoff Depth=2.29"Subcatchment Prop'd Trib: 1845 Monterey St Tc=10.0 min CN=97 Runoff=1.85 cfs 9,202 cf Peak Elev=297.06' Storage=4,015 cf Inflow=1.85 cfs 9,202 cfPond B1: 10" SD Outlet Discarded=0.01 cfs 816 cf Primary=0.48 cfs 5,504 cf Outflow=0.49 cfs 6,320 cf Total Runoff Area = 95,222 sf Runoff Volume = 16,313 cf Average Runoff Depth = 2.06" 23.60% Pervious = 22,477 sf 76.40% Impervious = 72,745 sf Type I 24-hr 2yr Rainfall=2.63"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 6HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff=1.47 cfs @ 10.01 hrs, Volume=7,111 cf, Depth=1.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 2yr Rainfall=2.63" Area (ac)CNDescription 0.71098Paved parking, HSG D 0.37080Pasture/grassland/range, Good, HSG D 1.08092Weighted Average 0.37034.26% Pervious Area 0.71065.74% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 1 0 Type I 24-hr 2yr Rainfall=2.63" Runoff Area=1.080 ac Runoff Volume=7,111 cf Runoff Depth=1.81" Tc=10.0 min CN=92 1.47 cfs Type I 24-hr 2yr Rainfall=2.63"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 7HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Prop'd Trib: 1845 Monterey St Runoff=1.85 cfs @ 10.00 hrs, Volume=9,202 cf, Depth=2.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 2yr Rainfall=2.63" Area (ac)CNDescription 0.03680>75% Grass cover, Good, HSG D 0.96098Paved parking, HSG D *0.11094Newly graded area (Pervious only), HSG D 1.10697Weighted Average 0.14613.20% Pervious Area 0.96086.80% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Prop'd Trib: 1845 Monterey St Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Type I 24-hr 2yr Rainfall=2.63" Runoff Area=1.106 ac Runoff Volume=9,202 cf Runoff Depth=2.29" Tc=10.0 min CN=97 1.85 cfs Type I 24-hr 2yr Rainfall=2.63"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 8HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond B1: 10" SD Outlet Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 2.29" for 2yr event Inflow=1.85 cfs @ 10.00 hrs, Volume=9,202 cf Outflow=0.49 cfs @ 10.30 hrs, Volume=6,320 cf, Atten= 74%, Lag= 17.6 min Discarded=0.01 cfs @ 10.30 hrs, Volume=816 cf Primary=0.48 cfs @ 10.30 hrs, Volume=5,504 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 297.06' @ 10.30 hrs Surf.Area= 1,615 sf Storage= 4,015 cf Plug-Flow detention time= 402.8 min calculated for 6,320 cf (69% of inflow) Center-of-Mass det. time= 252.1 min ( 977.6 - 725.6 ) VolumeInvertAvail.StorageStorage Description #1A294.03'861 cf 19.69'W x 82.02'L x 5.27'H Field A 8,509 cf Overall - 6,357 cf Embedded = 2,153 cf x 40.0% Voids #2A294.70'5,975 cf Rainstore3 12 x 150 Inside #1 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 6,836 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary294.80'10.0" Round Culvert L= 48.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 294.80' / 287.50' S= 0.1521 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #2Device 1296.90'5.5" Vert. Orifice/Grate X 6.00 C= 0.600 #3Device 1296.40'1.0" Vert. Orifice/Grate X 3.00 C= 0.600 #4Discarded294.03'0.150 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 283.00' #5Device 1299.40'24.0" Horiz. Orifice/Grate C= 0.600 Discarded OutFlow Max=0.01 cfs @ 10.30 hrs HW=297.06' (Free Discharge) 4=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=0.47 cfs @ 10.30 hrs HW=297.06' (Free Discharge) 1=Culvert (Passes 0.47 cfs of 3.56 cfs potential flow) 2=Orifice/Grate (Orifice Controls 0.41 cfs @ 1.35 fps) 3=Orifice/Grate (Orifice Controls 0.06 cfs @ 3.78 fps) 5=Orifice/Grate ( Controls 0.00 cfs) 8 oz/sq-yd minimum (271 g/sq-meter) non-woven geotextile filter fabric encasing Rainstore3 structure. Excavation line. Suitable structural backfill compacted to 95% modified proctor density. Catch basin or other suitable filtration system. (by others) Backfill compacted to 95% modified proctor density. 12" (0.3 m) minimum, 36" (0.9 m) maximum depth. 20" (0.5 m) minimum to allow space for proper compaction. Typical RS3 installation below paving for stormwater retention or detention Rainstore3 System NOT TO SCALE RS3detret10.dwg 1600 Jackson Street., Suite 310 Golden, Colorado 80401 800-233-1510 FAX: 800-233-1522 www.invisiblestructures.com rev 12/2010 Surfacing Geogrid (Tensar TriX 160 or equiv.) exterior of fabric.Non-corrosive hose clamp used to fasten liner to pipes to prevent backfill from entering structure. Detention outflow pipe if necessary. Sized for desired flow rate. Location near inflow allows suspended solids to exit before settling. Geogrid (Tensar TriX 160 or equiv.) 40" (1.0 m) geogrid (Tensar TriX 160 or equiv.) overlap. Excavation line. Geogrid (Tensar TriX 160 or equiv.) 8 oz/sq-yd minimum (271 g/sq-meter) non-woven geotextile filter fabric encasing Rainstore3 structure. Rainstore3 structure. Suitable structural backfill. Rainstore3 structure. 8 oz/sq-yd minimum (271 g/sq-meter) non-woven geotextile filter fabric encasing Rainstore3 structure. Suitable structural backfill compacted to 95% modified proctor density. Geogrid (Tensar TriX 160 or equiv.) Utility markers. Use metallic tape at corners of install to mark the area for future utility detection. Geogrid (Tensar TriX 160 or equiv.) exterior of fabric. Geogrid (Tensar TriX 160 or equiv.) interior of fabric. Type I 24-hr 2yr Rainfall=2.63"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 9HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet - Chamber Wizard Field A Chamber Model = Rainstore3 12 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 39.4" Wide = 39.4" C-C Row Spacing 25 Chambers/Row x 3.28' Long = 82.02' Row Length 6 Rows x 39.4" Wide = 19.69' Base Width 8.0" Base + 47.2" Chamber Height + 8.0" Cover = 5.27' Field Height 150 Chambers x 39.8 cf = 5,975.2 cf Chamber Storage 150 Chambers x 42.4 cf = 6,356.6 cf Displacement 8,509.4 cf Field - 6,356.6 cf Chambers = 2,152.8 cf Stone x 40.0% Voids = 861.1 cf Stone Storage Chamber Storage + Stone Storage = 6,836.4 cf = 0.157 af Overall Storage Efficiency = 80.3% Type I 24-hr 2yr Rainfall=2.63"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 10HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet Inflow Outflow Discarded Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Inflow Area=48,177 sf Peak Elev=297.06' Storage=4,015 cf 1.85 cfs 0.49 cfs 0.01 cfs 0.48 cfs Type I 24-hr 5yr Rainfall=3.45"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 11HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.02 hrs, 1801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=1.080 ac 65.74% Impervious Runoff Depth=2.59"Subcatchment Ex. WSA (disturbed): 1845 Monterey Street Tc=10.0 min CN=92 Runoff=2.10 cfs 10,150 cf Runoff Area=1.106 ac 86.80% Impervious Runoff Depth=3.10"Subcatchment Prop'd Trib: 1845 Monterey St Tc=10.0 min CN=97 Runoff=2.47 cfs 12,465 cf Peak Elev=297.30' Storage=4,377 cf Inflow=2.47 cfs 12,465 cfPond B1: 10" SD Outlet Discarded=0.01 cfs 832 cf Primary=2.02 cfs 8,737 cf Outflow=2.03 cfs 9,569 cf Total Runoff Area = 95,222 sf Runoff Volume = 22,614 cf Average Runoff Depth = 2.85" 23.60% Pervious = 22,477 sf 76.40% Impervious = 72,745 sf Type I 24-hr 5yr Rainfall=3.45"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 12HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff=2.10 cfs @ 10.01 hrs, Volume=10,150 cf, Depth=2.59" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 5yr Rainfall=3.45" Area (ac)CNDescription 0.71098Paved parking, HSG D 0.37080Pasture/grassland/range, Good, HSG D 1.08092Weighted Average 0.37034.26% Pervious Area 0.71065.74% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Type I 24-hr 5yr Rainfall=3.45" Runoff Area=1.080 ac Runoff Volume=10,150 cf Runoff Depth=2.59" Tc=10.0 min CN=92 2.10 cfs Type I 24-hr 5yr Rainfall=3.45"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 13HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Prop'd Trib: 1845 Monterey St Runoff=2.47 cfs @ 10.00 hrs, Volume=12,465 cf, Depth=3.10" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 5yr Rainfall=3.45" Area (ac)CNDescription 0.03680>75% Grass cover, Good, HSG D 0.96098Paved parking, HSG D *0.11094Newly graded area (Pervious only), HSG D 1.10697Weighted Average 0.14613.20% Pervious Area 0.96086.80% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Prop'd Trib: 1845 Monterey St Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Type I 24-hr 5yr Rainfall=3.45" Runoff Area=1.106 ac Runoff Volume=12,465 cf Runoff Depth=3.10" Tc=10.0 min CN=97 2.47 cfs Type I 24-hr 5yr Rainfall=3.45"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 14HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond B1: 10" SD Outlet Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 3.10" for 5yr event Inflow=2.47 cfs @ 10.00 hrs, Volume=12,465 cf Outflow=2.03 cfs @ 10.07 hrs, Volume=9,569 cf, Atten= 18%, Lag= 4.3 min Discarded=0.01 cfs @ 10.07 hrs, Volume=832 cf Primary=2.02 cfs @ 10.07 hrs, Volume=8,737 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 297.30' @ 10.07 hrs Surf.Area= 1,615 sf Storage= 4,377 cf Plug-Flow detention time= 310.6 min calculated for 9,569 cf (77% of inflow) Center-of-Mass det. time= 186.3 min ( 902.9 - 716.7 ) VolumeInvertAvail.StorageStorage Description #1A294.03'861 cf 19.69'W x 82.02'L x 5.27'H Field A 8,509 cf Overall - 6,357 cf Embedded = 2,153 cf x 40.0% Voids #2A294.70'5,975 cf Rainstore3 12 x 150 Inside #1 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 6,836 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary294.80'10.0" Round Culvert L= 48.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 294.80' / 287.50' S= 0.1521 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #2Device 1296.90'5.5" Vert. Orifice/Grate X 6.00 C= 0.600 #3Device 1296.40'1.0" Vert. Orifice/Grate X 3.00 C= 0.600 #4Discarded294.03'0.150 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 283.00' #5Device 1299.40'24.0" Horiz. Orifice/Grate C= 0.600 Discarded OutFlow Max=0.01 cfs @ 10.07 hrs HW=297.30' (Free Discharge) 4=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=2.02 cfs @ 10.07 hrs HW=297.30' (Free Discharge) 1=Culvert (Passes 2.02 cfs of 3.79 cfs potential flow) 2=Orifice/Grate (Orifice Controls 1.95 cfs @ 2.14 fps) 3=Orifice/Grate (Orifice Controls 0.07 cfs @ 4.45 fps) 5=Orifice/Grate ( Controls 0.00 cfs) Type I 24-hr 5yr Rainfall=3.45"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 15HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet - Chamber Wizard Field A Chamber Model = Rainstore3 12 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 39.4" Wide = 39.4" C-C Row Spacing 25 Chambers/Row x 3.28' Long = 82.02' Row Length 6 Rows x 39.4" Wide = 19.69' Base Width 8.0" Base + 47.2" Chamber Height + 8.0" Cover = 5.27' Field Height 150 Chambers x 39.8 cf = 5,975.2 cf Chamber Storage 150 Chambers x 42.4 cf = 6,356.6 cf Displacement 8,509.4 cf Field - 6,356.6 cf Chambers = 2,152.8 cf Stone x 40.0% Voids = 861.1 cf Stone Storage Chamber Storage + Stone Storage = 6,836.4 cf = 0.157 af Overall Storage Efficiency = 80.3% Type I 24-hr 5yr Rainfall=3.45"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 16HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet Inflow Outflow Discarded Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Inflow Area=48,177 sf Peak Elev=297.30' Storage=4,377 cf 2.47 cfs 2.03 cfs 0.01 cfs 2.02 cfs Type I 24-hr 10yr Rainfall=4.11"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 17HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.02 hrs, 1801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=1.080 ac 65.74% Impervious Runoff Depth=3.22"Subcatchment Ex. WSA (disturbed): 1845 Monterey Street Tc=10.0 min CN=92 Runoff=2.60 cfs 12,639 cf Runoff Area=1.106 ac 86.80% Impervious Runoff Depth=3.76"Subcatchment Prop'd Trib: 1845 Monterey St Tc=10.0 min CN=97 Runoff=2.97 cfs 15,099 cf Peak Elev=297.41' Storage=4,548 cf Inflow=2.97 cfs 15,099 cfPond B1: 10" SD Outlet Discarded=0.01 cfs 842 cf Primary=2.60 cfs 11,358 cf Outflow=2.61 cfs 12,199 cf Total Runoff Area = 95,222 sf Runoff Volume = 27,738 cf Average Runoff Depth = 3.50" 23.60% Pervious = 22,477 sf 76.40% Impervious = 72,745 sf Type I 24-hr 10yr Rainfall=4.11"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 18HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff=2.60 cfs @ 10.01 hrs, Volume=12,639 cf, Depth=3.22" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 10yr Rainfall=4.11" Area (ac)CNDescription 0.71098Paved parking, HSG D 0.37080Pasture/grassland/range, Good, HSG D 1.08092Weighted Average 0.37034.26% Pervious Area 0.71065.74% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 2 1 0 Type I 24-hr 10yr Rainfall=4.11" Runoff Area=1.080 ac Runoff Volume=12,639 cf Runoff Depth=3.22" Tc=10.0 min CN=92 2.60 cfs Type I 24-hr 10yr Rainfall=4.11"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 19HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Prop'd Trib: 1845 Monterey St Runoff=2.97 cfs @ 10.00 hrs, Volume=15,099 cf, Depth=3.76" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 10yr Rainfall=4.11" Area (ac)CNDescription 0.03680>75% Grass cover, Good, HSG D 0.96098Paved parking, HSG D *0.11094Newly graded area (Pervious only), HSG D 1.10697Weighted Average 0.14613.20% Pervious Area 0.96086.80% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Prop'd Trib: 1845 Monterey St Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 3 2 1 0 Type I 24-hr 10yr Rainfall=4.11" Runoff Area=1.106 ac Runoff Volume=15,099 cf Runoff Depth=3.76" Tc=10.0 min CN=97 2.97 cfs Type I 24-hr 10yr Rainfall=4.11"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 20HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond B1: 10" SD Outlet Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 3.76" for 10yr event Inflow=2.97 cfs @ 10.00 hrs, Volume=15,099 cf Outflow=2.61 cfs @ 10.06 hrs, Volume=12,199 cf, Atten= 12%, Lag= 3.4 min Discarded=0.01 cfs @ 10.06 hrs, Volume=842 cf Primary=2.60 cfs @ 10.06 hrs, Volume=11,358 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 297.41' @ 10.06 hrs Surf.Area= 1,615 sf Storage= 4,548 cf Plug-Flow detention time= 266.5 min calculated for 12,199 cf (81% of inflow) Center-of-Mass det. time= 158.0 min ( 869.6 - 711.6 ) VolumeInvertAvail.StorageStorage Description #1A294.03'861 cf 19.69'W x 82.02'L x 5.27'H Field A 8,509 cf Overall - 6,357 cf Embedded = 2,153 cf x 40.0% Voids #2A294.70'5,975 cf Rainstore3 12 x 150 Inside #1 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 6,836 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary294.80'10.0" Round Culvert L= 48.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 294.80' / 287.50' S= 0.1521 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #2Device 1296.90'5.5" Vert. Orifice/Grate X 6.00 C= 0.600 #3Device 1296.40'1.0" Vert. Orifice/Grate X 3.00 C= 0.600 #4Discarded294.03'0.150 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 283.00' #5Device 1299.40'24.0" Horiz. Orifice/Grate C= 0.600 Discarded OutFlow Max=0.01 cfs @ 10.06 hrs HW=297.41' (Free Discharge) 4=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=2.60 cfs @ 10.06 hrs HW=297.41' (Free Discharge) 1=Culvert (Passes 2.60 cfs of 3.89 cfs potential flow) 2=Orifice/Grate (Orifice Controls 2.52 cfs @ 2.55 fps) 3=Orifice/Grate (Orifice Controls 0.08 cfs @ 4.74 fps) 5=Orifice/Grate ( Controls 0.00 cfs) Type I 24-hr 10yr Rainfall=4.11"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 21HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet - Chamber Wizard Field A Chamber Model = Rainstore3 12 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 39.4" Wide = 39.4" C-C Row Spacing 25 Chambers/Row x 3.28' Long = 82.02' Row Length 6 Rows x 39.4" Wide = 19.69' Base Width 8.0" Base + 47.2" Chamber Height + 8.0" Cover = 5.27' Field Height 150 Chambers x 39.8 cf = 5,975.2 cf Chamber Storage 150 Chambers x 42.4 cf = 6,356.6 cf Displacement 8,509.4 cf Field - 6,356.6 cf Chambers = 2,152.8 cf Stone x 40.0% Voids = 861.1 cf Stone Storage Chamber Storage + Stone Storage = 6,836.4 cf = 0.157 af Overall Storage Efficiency = 80.3% Type I 24-hr 10yr Rainfall=4.11"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 22HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet Inflow Outflow Discarded Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 3 2 1 0 Inflow Area=48,177 sf Peak Elev=297.41' Storage=4,548 cf 2.97 cfs 2.61 cfs 0.01 cfs 2.60 cfs Type I 24-hr 25yr Rainfall=4.97"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 23HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.02 hrs, 1801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=1.080 ac 65.74% Impervious Runoff Depth=4.06"Subcatchment Ex. WSA (disturbed): 1845 Monterey Street Tc=10.0 min CN=92 Runoff=3.25 cfs 15,917 cf Runoff Area=1.106 ac 86.80% Impervious Runoff Depth=4.62"Subcatchment Prop'd Trib: 1845 Monterey St Tc=10.0 min CN=97 Runoff=3.61 cfs 18,537 cf Peak Elev=297.53' Storage=4,731 cf Inflow=3.61 cfs 18,537 cfPond B1: 10" SD Outlet Discarded=0.01 cfs 851 cf Primary=3.10 cfs 14,784 cf Outflow=3.11 cfs 15,635 cf Total Runoff Area = 95,222 sf Runoff Volume = 34,454 cf Average Runoff Depth = 4.34" 23.60% Pervious = 22,477 sf 76.40% Impervious = 72,745 sf Type I 24-hr 25yr Rainfall=4.97"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 24HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff=3.25 cfs @ 10.01 hrs, Volume=15,917 cf, Depth=4.06" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 25yr Rainfall=4.97" Area (ac)CNDescription 0.71098Paved parking, HSG D 0.37080Pasture/grassland/range, Good, HSG D 1.08092Weighted Average 0.37034.26% Pervious Area 0.71065.74% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 3 2 1 0 Type I 24-hr 25yr Rainfall=4.97" Runoff Area=1.080 ac Runoff Volume=15,917 cf Runoff Depth=4.06" Tc=10.0 min CN=92 3.25 cfs Type I 24-hr 25yr Rainfall=4.97"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 25HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Prop'd Trib: 1845 Monterey St Runoff=3.61 cfs @ 10.00 hrs, Volume=18,537 cf, Depth=4.62" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 25yr Rainfall=4.97" Area (ac)CNDescription 0.03680>75% Grass cover, Good, HSG D 0.96098Paved parking, HSG D *0.11094Newly graded area (Pervious only), HSG D 1.10697Weighted Average 0.14613.20% Pervious Area 0.96086.80% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Prop'd Trib: 1845 Monterey St Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Type I 24-hr 25yr Rainfall=4.97" Runoff Area=1.106 ac Runoff Volume=18,537 cf Runoff Depth=4.62" Tc=10.0 min CN=97 3.61 cfs Type I 24-hr 25yr Rainfall=4.97"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 26HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond B1: 10" SD Outlet Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 4.62" for 25yr event Inflow=3.61 cfs @ 10.00 hrs, Volume=18,537 cf Outflow=3.11 cfs @ 10.06 hrs, Volume=15,635 cf, Atten= 14%, Lag= 3.7 min Discarded=0.01 cfs @ 10.06 hrs, Volume=851 cf Primary=3.10 cfs @ 10.06 hrs, Volume=14,784 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 297.53' @ 10.06 hrs Surf.Area= 1,615 sf Storage= 4,731 cf Plug-Flow detention time= 227.6 min calculated for 15,635 cf (84% of inflow) Center-of-Mass det. time= 134.8 min ( 841.4 - 706.7 ) VolumeInvertAvail.StorageStorage Description #1A294.03'861 cf 19.69'W x 82.02'L x 5.27'H Field A 8,509 cf Overall - 6,357 cf Embedded = 2,153 cf x 40.0% Voids #2A294.70'5,975 cf Rainstore3 12 x 150 Inside #1 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 6,836 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary294.80'10.0" Round Culvert L= 48.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 294.80' / 287.50' S= 0.1521 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #2Device 1296.90'5.5" Vert. Orifice/Grate X 6.00 C= 0.600 #3Device 1296.40'1.0" Vert. Orifice/Grate X 3.00 C= 0.600 #4Discarded294.03'0.150 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 283.00' #5Device 1299.40'24.0" Horiz. Orifice/Grate C= 0.600 Discarded OutFlow Max=0.01 cfs @ 10.06 hrs HW=297.53' (Free Discharge) 4=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=3.09 cfs @ 10.06 hrs HW=297.53' (Free Discharge) 1=Culvert (Passes 3.09 cfs of 3.99 cfs potential flow) 2=Orifice/Grate (Orifice Controls 3.01 cfs @ 3.04 fps) 3=Orifice/Grate (Orifice Controls 0.08 cfs @ 5.02 fps) 5=Orifice/Grate ( Controls 0.00 cfs) Type I 24-hr 25yr Rainfall=4.97"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 27HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet - Chamber Wizard Field A Chamber Model = Rainstore3 12 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 39.4" Wide = 39.4" C-C Row Spacing 25 Chambers/Row x 3.28' Long = 82.02' Row Length 6 Rows x 39.4" Wide = 19.69' Base Width 8.0" Base + 47.2" Chamber Height + 8.0" Cover = 5.27' Field Height 150 Chambers x 39.8 cf = 5,975.2 cf Chamber Storage 150 Chambers x 42.4 cf = 6,356.6 cf Displacement 8,509.4 cf Field - 6,356.6 cf Chambers = 2,152.8 cf Stone x 40.0% Voids = 861.1 cf Stone Storage Chamber Storage + Stone Storage = 6,836.4 cf = 0.157 af Overall Storage Efficiency = 80.3% Type I 24-hr 25yr Rainfall=4.97"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 28HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet Inflow Outflow Discarded Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Inflow Area=48,177 sf Peak Elev=297.53' Storage=4,731 cf 3.61 cfs 3.11 cfs 0.01 cfs 3.10 cfs Type I 24-hr 50yr Rainfall=5.61"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 29HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.02 hrs, 1801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=1.080 ac 65.74% Impervious Runoff Depth=4.69"Subcatchment Ex. WSA (disturbed): 1845 Monterey Street Tc=10.0 min CN=92 Runoff=3.73 cfs 18,373 cf Runoff Area=1.106 ac 86.80% Impervious Runoff Depth=5.26"Subcatchment Prop'd Trib: 1845 Monterey St Tc=10.0 min CN=97 Runoff=4.09 cfs 21,098 cf Peak Elev=297.63' Storage=4,877 cf Inflow=4.09 cfs 21,098 cfPond B1: 10" SD Outlet Discarded=0.01 cfs 856 cf Primary=3.45 cfs 17,339 cf Outflow=3.45 cfs 18,196 cf Total Runoff Area = 95,222 sf Runoff Volume = 39,471 cf Average Runoff Depth = 4.97" 23.60% Pervious = 22,477 sf 76.40% Impervious = 72,745 sf Type I 24-hr 50yr Rainfall=5.61"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 30HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff=3.73 cfs @ 10.00 hrs, Volume=18,373 cf, Depth=4.69" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 50yr Rainfall=5.61" Area (ac)CNDescription 0.71098Paved parking, HSG D 0.37080Pasture/grassland/range, Good, HSG D 1.08092Weighted Average 0.37034.26% Pervious Area 0.71065.74% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Type I 24-hr 50yr Rainfall=5.61" Runoff Area=1.080 ac Runoff Volume=18,373 cf Runoff Depth=4.69" Tc=10.0 min CN=92 3.73 cfs Type I 24-hr 50yr Rainfall=5.61"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 31HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Prop'd Trib: 1845 Monterey St Runoff=4.09 cfs @ 10.00 hrs, Volume=21,098 cf, Depth=5.26" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 50yr Rainfall=5.61" Area (ac)CNDescription 0.03680>75% Grass cover, Good, HSG D 0.96098Paved parking, HSG D *0.11094Newly graded area (Pervious only), HSG D 1.10697Weighted Average 0.14613.20% Pervious Area 0.96086.80% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Prop'd Trib: 1845 Monterey St Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Type I 24-hr 50yr Rainfall=5.61" Runoff Area=1.106 ac Runoff Volume=21,098 cf Runoff Depth=5.26" Tc=10.0 min CN=97 4.09 cfs Type I 24-hr 50yr Rainfall=5.61"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 32HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond B1: 10" SD Outlet Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 5.26" for 50yr event Inflow=4.09 cfs @ 10.00 hrs, Volume=21,098 cf Outflow=3.45 cfs @ 10.07 hrs, Volume=18,196 cf, Atten= 16%, Lag= 3.9 min Discarded=0.01 cfs @ 10.07 hrs, Volume=856 cf Primary=3.45 cfs @ 10.07 hrs, Volume=17,339 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 297.63' @ 10.07 hrs Surf.Area= 1,615 sf Storage= 4,877 cf Plug-Flow detention time= 205.8 min calculated for 18,185 cf (86% of inflow) Center-of-Mass det. time= 122.4 min ( 826.2 - 703.8 ) VolumeInvertAvail.StorageStorage Description #1A294.03'861 cf 19.69'W x 82.02'L x 5.27'H Field A 8,509 cf Overall - 6,357 cf Embedded = 2,153 cf x 40.0% Voids #2A294.70'5,975 cf Rainstore3 12 x 150 Inside #1 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 6,836 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary294.80'10.0" Round Culvert L= 48.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 294.80' / 287.50' S= 0.1521 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #2Device 1296.90'5.5" Vert. Orifice/Grate X 6.00 C= 0.600 #3Device 1296.40'1.0" Vert. Orifice/Grate X 3.00 C= 0.600 #4Discarded294.03'0.150 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 283.00' #5Device 1299.40'24.0" Horiz. Orifice/Grate C= 0.600 Discarded OutFlow Max=0.01 cfs @ 10.07 hrs HW=297.62' (Free Discharge) 4=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=3.44 cfs @ 10.07 hrs HW=297.62' (Free Discharge) 1=Culvert (Passes 3.44 cfs of 4.07 cfs potential flow) 2=Orifice/Grate (Orifice Controls 3.35 cfs @ 3.39 fps) 3=Orifice/Grate (Orifice Controls 0.09 cfs @ 5.24 fps) 5=Orifice/Grate ( Controls 0.00 cfs) Type I 24-hr 50yr Rainfall=5.61"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 33HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet - Chamber Wizard Field A Chamber Model = Rainstore3 12 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 39.4" Wide = 39.4" C-C Row Spacing 25 Chambers/Row x 3.28' Long = 82.02' Row Length 6 Rows x 39.4" Wide = 19.69' Base Width 8.0" Base + 47.2" Chamber Height + 8.0" Cover = 5.27' Field Height 150 Chambers x 39.8 cf = 5,975.2 cf Chamber Storage 150 Chambers x 42.4 cf = 6,356.6 cf Displacement 8,509.4 cf Field - 6,356.6 cf Chambers = 2,152.8 cf Stone x 40.0% Voids = 861.1 cf Stone Storage Chamber Storage + Stone Storage = 6,836.4 cf = 0.157 af Overall Storage Efficiency = 80.3% Type I 24-hr 50yr Rainfall=5.61"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 34HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet Inflow Outflow Discarded Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Inflow Area=48,177 sf Peak Elev=297.63' Storage=4,877 cf 4.09 cfs 3.45 cfs 0.01 cfs 3.45 cfs Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 35HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Time span=0.00-36.00 hrs, dt=0.02 hrs, 1801 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Runoff Area=1.080 ac 65.74% Impervious Runoff Depth=5.32"Subcatchment Ex. WSA (disturbed): 1845 Monterey Street Tc=10.0 min CN=92 Runoff=4.21 cfs 20,838 cf Runoff Area=1.106 ac 86.80% Impervious Runoff Depth=5.89"Subcatchment Prop'd Trib: 1845 Monterey St Tc=10.0 min CN=97 Runoff=4.57 cfs 23,661 cf Peak Elev=297.73' Storage=5,033 cf Inflow=4.57 cfs 23,661 cfPond B1: 10" SD Outlet Discarded=0.01 cfs 861 cf Primary=3.78 cfs 19,897 cf Outflow=3.79 cfs 20,758 cf Total Runoff Area = 95,222 sf Runoff Volume = 44,500 cf Average Runoff Depth = 5.61" 23.60% Pervious = 22,477 sf 76.40% Impervious = 72,745 sf Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 36HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff=4.21 cfs @ 10.00 hrs, Volume=20,838 cf, Depth=5.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 100yr Rainfall=6.25" Area (ac)CNDescription 0.71098Paved parking, HSG D 0.37080Pasture/grassland/range, Good, HSG D 1.08092Weighted Average 0.37034.26% Pervious Area 0.71065.74% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Ex. WSA (disturbed): 1845 Monterey Street (disturbed area) Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 4 3 2 1 0 Type I 24-hr 100yr Rainfall=6.25" Runoff Area=1.080 ac Runoff Volume=20,838 cf Runoff Depth=5.32" Tc=10.0 min CN=92 4.21 cfs Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 37HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Subcatchment Prop'd Trib: 1845 Monterey St Runoff=4.57 cfs @ 10.00 hrs, Volume=23,661 cf, Depth=5.89" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Type I 24-hr 100yr Rainfall=6.25" Area (ac)CNDescription 0.03680>75% Grass cover, Good, HSG D 0.96098Paved parking, HSG D *0.11094Newly graded area (Pervious only), HSG D 1.10697Weighted Average 0.14613.20% Pervious Area 0.96086.80% Impervious Area TcLengthSlopeVelocityCapacityDescription (min)(feet)(ft/ft)(ft/sec)(cfs) 10.0 Direct Entry, Min Tc Subcatchment Prop'd Trib: 1845 Monterey St Runoff Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 5 4 3 2 1 0 Type I 24-hr 100yr Rainfall=6.25" Runoff Area=1.106 ac Runoff Volume=23,661 cf Runoff Depth=5.89" Tc=10.0 min CN=97 4.57 cfs Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 38HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond B1: 10" SD Outlet Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 5.89" for 100yr event Inflow=4.57 cfs @ 10.00 hrs, Volume=23,661 cf Outflow=3.79 cfs @ 10.07 hrs, Volume=20,758 cf, Atten= 17%, Lag= 4.1 min Discarded=0.01 cfs @ 10.07 hrs, Volume=861 cf Primary=3.78 cfs @ 10.07 hrs, Volume=19,897 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 297.73' @ 10.07 hrs Surf.Area= 1,615 sf Storage= 5,033 cf Plug-Flow detention time= 188.6 min calculated for 20,746 cf (88% of inflow) Center-of-Mass det. time= 112.7 min ( 814.1 - 701.4 ) VolumeInvertAvail.StorageStorage Description #1A294.03'861 cf 19.69'W x 82.02'L x 5.27'H Field A 8,509 cf Overall - 6,357 cf Embedded = 2,153 cf x 40.0% Voids #2A294.70'5,975 cf Rainstore3 12 x 150 Inside #1 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 6,836 cfTotal Available Storage Storage Group A created with Chamber Wizard DeviceRouting InvertOutlet Devices #1Primary294.80'10.0" Round Culvert L= 48.0' CPP, square edge headwall, Ke= 0.500 Inlet / Outlet Invert= 294.80' / 287.50' S= 0.1521 '/' Cc= 0.900 n= 0.010 PVC, smooth interior, Flow Area= 0.55 sf #2Device 1296.90'5.5" Vert. Orifice/Grate X 6.00 C= 0.600 #3Device 1296.40'1.0" Vert. Orifice/Grate X 3.00 C= 0.600 #4Discarded294.03'0.150 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 283.00' #5Device 1299.40'24.0" Horiz. Orifice/Grate C= 0.600 Discarded OutFlow Max=0.01 cfs @ 10.07 hrs HW=297.73' (Free Discharge) 4=Exfiltration ( Controls 0.01 cfs) Primary OutFlow Max=3.77 cfs @ 10.07 hrs HW=297.73' (Free Discharge) 1=Culvert (Passes 3.77 cfs of 4.16 cfs potential flow) 2=Orifice/Grate (Orifice Controls 3.68 cfs @ 3.72 fps) 3=Orifice/Grate (Orifice Controls 0.09 cfs @ 5.46 fps) 5=Orifice/Grate ( Controls 0.00 cfs) Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 39HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet - Chamber Wizard Field A Chamber Model = Rainstore3 12 Inside= 39.4"W x 47.2"H => 12.14 sf x 3.28'L = 39.8 cf Outside= 39.4"W x 47.2"H => 12.92 sf x 3.28'L = 42.4 cf 39.4" Wide = 39.4" C-C Row Spacing 25 Chambers/Row x 3.28' Long = 82.02' Row Length 6 Rows x 39.4" Wide = 19.69' Base Width 8.0" Base + 47.2" Chamber Height + 8.0" Cover = 5.27' Field Height 150 Chambers x 39.8 cf = 5,975.2 cf Chamber Storage 150 Chambers x 42.4 cf = 6,356.6 cf Displacement 8,509.4 cf Field - 6,356.6 cf Chambers = 2,152.8 cf Stone x 40.0% Voids = 861.1 cf Stone Storage Chamber Storage + Stone Storage = 6,836.4 cf = 0.157 af Overall Storage Efficiency = 80.3% Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 40HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Pond B1: 10" SD Outlet Inflow Outflow Discarded Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 5 4 3 2 1 0 Inflow Area=48,177 sf Peak Elev=297.73' Storage=5,033 cf 4.57 cfs 3.79 cfs 0.01 cfs 3.78 cfs Type I 24-hr 100yr Rainfall=6.25"__2014March31_1215-01 PrelimHyd Printed 4/2/2014Prepared by WALLACE GROUP Page 1HydroCAD® 10.00 s/n 06276 © 2012 HydroCAD Software Solutions LLC Summary for Pond 2P: Level Spreader [57] Hint: Peaked at 300.05' (Flood elevation advised) Inflow Area =48,177 sf,86.80% Impervious, Inflow Depth = 5.89" for 100yr event Inflow=4.57 cfs @ 10.00 hrs, Volume=23,661 cf Outflow=4.57 cfs @ 10.00 hrs, Volume=23,661 cf, Atten= 0%, Lag= 0.0 min Primary=4.57 cfs @ 10.00 hrs, Volume=23,661 cf Routing by Stor-Ind method, Time Span= 0.00-36.00 hrs, dt= 0.02 hrs Peak Elev= 300.05' @ 10.00 hrs DeviceRouting InvertOutlet Devices #1Primary299.90'24.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 0.5' Crest Height Primary OutFlow Max=4.56 cfs @ 10.00 hrs HW=300.05' (Free Discharge) 1=Sharp-Crested Rectangular Weir (Weir Controls 4.56 cfs @ 1.30 fps) Pond 2P: Level Spreader Inflow Primary Hydrograph Time (hours) 3635343332313029282726252423222120191817161514131211109876543210 Fl o w ( c f s ) 5 4 3 2 1 0 Inflow Area=48,177 sf Peak Elev=300.05' 4.57 cfs4.57 cfs the MONTEREY Hotel Development Page 75 1215.0001 PRELIMINARY STORMWATER CONTROL PLAN AND BASIN ANALYSIS REPORT ADDENDUM 4/9/2014 APPENDIX F LOW IMPACT DEVELOPMENT VOLUME CALCULATIONS 2 1.7 1.6 1.5 1 1.3 1.4 1.8 1.9 1.2 2.2 2.1 2.4 2.3 1.1 2.8 3.2 4 3.6 0.9 4.4 0.8 1.6 1.6 2.2 1.5 1 1.9 1.8 1.5 2.1 3.6 1.7 2.8 1.7 1.9 1.1 2.1 2 1.2 1.4 1.3 1.9 2.8 1.8 1.3 2.2 2 1.9 1.4 1.8 1.5 2.4 1.3 2 3.2 2.4 1.7 1.3 2.2 1.2 1.6 1.2 2.8 1.7 2 2 2.4 2.3 1.3 2.2 1.8 1.6 1.4 2.4 2.4 1.8 1.8 1.2 1.6 2.3 1.7 1.4 2.4 1.1 2.8 1.7 1.4 1.9 2.4 1.2 2.1 2.2 1.5 1.5 1.4 2.4 2.4 2.2 1.9 0.9 3.2 1.6 2.8 1.7 1.8 2.1 2.8 1.6 1.4 1.8 2.8 1.2 1.7 1.8 2.3 1.9 2.4 1.4 1.6 1.8 1.9 2.1 1.7 2.4 1 2 2 2.1 1.7 1.6 1.9 1.5 2 1 1.5 2 2.4 1.3 2.3 2.2 1.1 1.7 1.5 1.7 2.3 2.2 2.8 1.2 1.6 0.9 1.2 1.8 1.1 1.5 1.4 1.6 1.4 1.7 1.7 1.8 1.4 2.3 1.8 1.6 1.3 2.3 1.92.1 1.5 2 3.2 2.8 2.1 1.8 3.6 1.9 2.1 2.3 1.6 2.2 1.7 2.3 1 1.7 2.8 2.3 1.6 2.3 2.3 2 1.4 2.2 1.7 1.7 1.4 1.8 2.1 1.3 2 2.3 1.7 1.7 1.5 1.3 1.9 1.8 2.4 1.6 1.5 1.9 1.3 1.4 2.1 1.7 2.4 1.1 Pozo Rd State Rte198 Carrisa Hwy State Rte 166 W Main St State Rte 246 Salinas Hwy Cannon Rd Hecker Pass Hwy Foothill Rd Cliff Dr Big BasinHwy State Hwy 166 1st St Cuyama Hwy Green Valley Rd US Hwy 399 Willow Rd E Cabrillo Blvd San Juan Rd South St W Centre St E Main St Armour Ranch Rd Cienaga St Interlake Rd Sunset Dr TresPinos Rd State Hwy 166 State Hwy 46 Casitas Pass Rd Coast Rd el Camino Real CoastRd State Rte 1 State Rte 166 Sources: Esri, DeLorme, TomTom, USGS, Esri Japan, Esri China (Hong Kong) Legend Isohyetal 0.1 inch interval 0.4 inch interval Roads Project Boundary Precipitation (inch) 95 Percentile (1949 - 2010) < 0.8 0.8 - 0.9 0.9 - 1.0 1.0 - 1.1 1.1 - 1.2 1.2 - 1.3 1.3 - 1.4 1.4 - 1.5 1.5 - 1.6 1.6 - 1.7 1.7 - 1.8 1.8 - 1.9 1.9 - 2.0 2.0 - 2.1 2.1 - 2.2 2.2 - 2.3 2.3 - 2.4 2.4 - 2.8 2.8 - 3.2 3.2 - 3.6 3.6 - 4.0 4.0 - 4.4 > 4.4 0 40 8020 Miles 0 40 8020 Kilometers NAD 1983 California Teale Albers Data Source (for spatial variation): PRISM Climate Group Oregon State University http://prism.oregonstate.edu Central Coast Region 95 Percentile 24-hour Rainfall Depthth th 1845 Monterey Street Hotel Project Site 18 6 5 MO N T E R E Y ST R E E T IN V E S T O R S , L. P . th e MO N T E R E Y LO W IM P A C T DE V E L O P M E N T RE T E N T I O N VO L U M E CA L C U L A T I O N S Pr o j e c t 95 % Ra i n f a l l De p t h in . To t a l Pr o j e c t Ar e a Ac r e s Re t e n t i o n Tr i b u t a r y Ar e a Ac r e s i, im p e r v i o u s ar e a Ac r e s % i C, LI D Ru n o f f Co e f f i c i e n t 95 % Vo l u m e CF 12 1 5 . 0 1 MS t H 2 . 0 8 1 . 9 3 1 . 0 8 0 . 9 3 0 . 8 6 0 . 6 8 5 5 3 3 40 6 0 4 0. 1 3 6 95 t h _ p e r c e n t i l e _ r a i n f a l l _ d e p t h _ m a p s . p d f To t a l Pr o j e c t Ar e a 8 4 , 2 7 7 . 7 1 . 9 3 Un d i s t u r b e d or La n d s c a p e d Ar e a 3 7 , 2 2 6 . 3 0 . 8 5 Si t e Di s t u r b a n c e Ar e a 4 7 , 0 5 1 . 5 1 . 0 8 DM A 1 2 3 , 0 1 9 . 3 0 . 5 3 DM A 2 7 , 8 3 1 . 1 0. 1 8 30 8 5 0 . 4 0. 7 1 ** & i) No t ap p l i c a b l e fo r ou r pr o j e c t du e to R3 ‐20 1 3 ‐00 3 2 , pg 8 DM A 1 & DM A 2 4 0 6 0 3 . 6 0 . 9 3 DM A 1 & DM A 2 6 1 5 2 . 4 0 . 1 4 RE P L A C E D IM P E R V I O U S AR E A 2 4 6 9 8 0 . 5 7 1. 0 7 1) De t e r m i n a t i o n of Re t e n t i o n Tr i b u t a r y Ar e a De t e r m i n i n g th e Re t e n t i o n Tr i b u t a r y Ar e a is th e ba s i s fo r ca l c u l a t i n g th e ru n o f f vo l u m e s su b j e c t to Pe r f o r m a n c e Re q u i r e m e n t Nu m b e r 3. Re t e n t i o n Tr i b u t a r y Ar e a sh o u l d be ca l c u l a t e d fo r ea c h in d i v i d u a l Dr a i n a g e Ma n a g e m e n t Ar e a to fa c i l i t a t e th e de s i g n of SC M s fo r ea c h Dr a i n a g e Ma n a g e m e n t Ar e a . Th e ge n e r i c eq u a t i o n be l o w il l u s t r a t e s ho w va r i o u s po r t i o n s of th e si t e ar e ad d r e s s e d wh e n de t e r m in i n g th e Re t e n t i o n Tr i b u t a r y Ar e a . Th e Re t e n t i o n Tr i b u t a r y Ar e a cal c u l a t i o n mu s t al s o ac c o u n t fo r th e ad j u s t m e n t s fo r Re d e v e l o p m e n t Pr o j e c t s su b j e c t to Pe r f o r m a n c e Re q u i r e m e n t No . 3. a) Co m p u t e th e Re t e n t i o n Tr i b u t a r y Ar e a , us i n g th e eq u a t i o n : Re t e n t i o n Tr i b u t a r y Ar e a = (E n t i r e Pr o j e c t Ar e a ) – (U n d i s t u r b e d or Pl a n t e d Ar e a s ) * – (I m p e r v i o u s Su rf a c e Ar e a s th a t Di s c h a r g e to In f i l t r a t i n g Ar e a s ) * * *A s de f i n e d in Se c t i o n B. 4 . d . i v . 1 . ** As de f i n e d in Se c t i o n B. 4 . d . i v . 2 . b) Ad j u s t m e n t s fo r Re d e v e l o p m e n t Pr o j e c t Re t e n t i o n Tr i b u t a r y Ar e a – Wh e r e th e Re g u l a t e d Pr o j e c t in c l u d e s re p l a c e d im p e r v i o u s su r f a c e , th e fo l l o w i n g Re t e n t i o n Tr i b u t a r y Ar e a ad j u s t m e n t s ap p l y : i) Re d e v e l o p m en t Pr o j e c t s ou t s i d e an ap p r o v e d Ur b a n Sus t a i n a b i l i t y Ar e a , as de s c r i b e d in Se c t i o n C. 3 . – Th e to t a l am o u n t of re p l a c e d im p e r v i o u s su r f a c e ar e a sh a l l be mu l t i p l i e d by 0. 5 wh e n ca l c u l a t i n g th e Re t e n t i o n Tr i b u t a r y Ar e a . EX I S T I N G IM P E R V I O U S RE P L A C E M E N T AR E A S PR O P O S E D IM P E R V I O U S AR E A S TH I S PR O J E C T ' S PR O P O S E D IM P E R V I O U S SU R F A C E DO E S NO T ME E T TH E CR I T E R I A PR O P O S E D PE R V I O U S AR E A S WA L L A C E GR O U P 12 1 5 . 0 1 4/ 1 / 2 0 1 4 20 1 4 . 0 3 . 2 1 ‐12 1 5 . 0 1 _ R W Q ‐LI D V o l . x l s x th e MO N T E R E Y LI D ON ‐SI T E RE T E N T I O N CA L C U L A T I O N S 5, 5 3 3 LI D Fe a t u r e St a c k a b l e / m o d u l a r St r u c t u r e fo r St o r m w a t e r St o r a g e , SF Pe r v i o u s Pa v e r DW Y 14 " de p t h O. G . Cl 2 AB , SF Pe r v i o u s Pa r k i n g Sp a c e s 8" de p t h O. G . CL 2 8" O. G . Cl 2 AB Un d e r Ra i n s t o r e 3, SF Vo l u m e Vo l u m e pe r Ar e a PC / P P 10 4 0 1 4 0 C F / S p a c e Ra i n s t o r e 3 1, 6 4 0 1, 6 4 0 36 7 7 2. 2 Pa v e r XS 3, 2 2 8 15 0 7 0. 5 55 8 5 PC R 3 RW Q Re s o l u t i o n R3 ‐20 1 3 ‐00 3 2 Vo l u m e CF WA L L A C E GR O U P DR T 12 1 5 . 0 1 4/ 1 / 2 0 1 4 20 1 4 . 0 3 . 2 1 ‐12 1 5 . 0 1 _ R W Q ‐LI D V o l . x l s x