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Drainage Report for GRD2007-00019 - GRD Letters / Memos - 6/23/2008
Mason County Review Checklist For a Stormwater Plan Instructions: This checklist is intended to assist Staff in the review of a Stormwater Plan. The Stormwater Plan is reviewed for completeness with respect to the 1992 Department of Ecology Manual. If an item is found to be not applicable, the Plan should explain the basis for the conclusion. The Plan is also reviewed for clarity and consistency. If the drawings, discussion, or recommendations are not understandable, they should be clarified. If they do not appear internally consistent or consistent with the application or observations on site, this needs to be corrected or explained. If resolution is not achieved with the author, staff should refer the case to the Planning Manager or Director. Applicant's Name: ��/ Permit# &wwq, 000v,( Parcel# 23 v 6000q Date(s) of the Document(s) reviewed: 2/�j LI-t U G (1) Erosion and Sediment Control: All new development and redevelopment that includes land disturbing activities of one acre or greater shall comply with erosion and sediment control requirements 1-14, below. Compliance with the Erosion and Sediment Control Requirements shall be demonstrated through implementation of a large parcel erosion and sediment control plan. All new development and redevelopment that includes land disturbing activities of less than one acre shall comply with the small parcel minimum requirements found in Section 14.48.130, Compliance with the small parcel requirements shall be demonstrated through implementation of a small parcel erosion and sediment control plan. 11* (a) Erosion and Sediment Control Requirement 1: Stabilization and Sediment Trapping. OK? Comment: (b) ErPion and Sediment Control Requirement#2: Delineate Clearing and Easement Limits. OK? Comment: 2 (c) Erand Sediment Control Requirement#3: Protection of Adjacent Properties. OK? Comment: (d) Ero ion and Sediment Control Requirement#4: Timing and Stabilization of Sediment Tra i g Measures. OK9 Comment: (e) Er sion and Sediment Control Requirement#5: Cut and Fill Slopes. OK?C4,0 Comment: (f) EVosion and Sediment Control Requirement#6: Controlling Off-Site Erosion. OK? Comment: (g) Er sion and Sediment Control Requirement#7: Stabilization of Temporary Conveyance Channels and Outlets. OK? 1124 Comment: (h) Er_ ion and Sediment Control Requirement#8: Storm Drain Inlet Protection. OK? rAfA Comment: (i) Er ion and Sediment Control Requirement#9: Underground Utility Construction. OK? Comment.- Er ion and Sediment Control Requirement#10: Construction Access Routes. OK? lAfA Comment: (k) Er sion and Sediment Control Requirement#11: Removal of Temporary BMPs. OK? i AA Comment: (1) Ero ion and Sediment Control Requirement#12: Dewatering Construction Sites. Page 1 of 3 Form Effective May 2009 OK? Comment: (m) Er�and Sediment Control Requirement#13: Control of Pollutants Other than Sediment on Construction Sites. OK? Comment: (n) Erosion and Sediment Control Requirement#14: Maintenance. OK?. �Comment: (o) Er sion and Sediment Control Requirement#15: Financial Liability. OK? Comment: (2) Preservation of Natural Drainage Systems. Natural drainage patterns shall be maintained, and disc r es from the site shall occur at the natural location to the maximum extent practicable. OK? Comment: 14�� (3) Source Control of Pollution. Source control BMPs shall be applied to all projects to the Yam. maximum extent practicable. Source control BMPs shall be selected, designed, and maintained accord'rngV�/o an approved manual. �A/ � OK?� =Comment: �i/�' (4) Runoff Treatment BMPs. All projects shall provide treatment of stormwater. Treatment BMPs shall be sized to capture and treat the water quality storm, defined as the six-month, twenty-four hour storm. The first priority for treatment of stormwater shall be to infiltrate as much as possible of the water quality design storm into the ground. Pretreatment of stormwater prior to infiltration into th ground may be required. ���� OK? Comment: (5) Streambank Erosion Control: The requirement below applies only to situations where stormwater runoff is discharged directly or indirectly to a stream, and must be met in addition to meeting the requirements in minimum requirement#4, Runoff Treatment BMPs. OK? Comment: (6) Wetlands: Stormwater discharges to wetlands shall maintain the wetland's natural hydroperiod and flows to the extent needed to preserve or enhance its existing functions and values. Prior to proposing discharge of higher volumes of stormwater to a wetland, alternative discharge, detention, and infiltration practices located in areas outside the wetland shall be evaluated and emplo ed b the project engineer where feasible and practicable. OK? Comment: yleg-e (7) Water Quality Sensitive Areas. Where the Mason County commissioners or their designee determine that the minimum requirements do not provide adequate protection of water quality sensitive areas, either on-site or within the basin, more stringent controls shall be required to protect water quality. An adopted and implemented basin plan (minimum requirement#9) may be used t develop requirements for water quality a sit" e h t are tailored to a specific basin. OK?Comment: (8) Off-Site Analysis and Mitigation. Downstream analysis may trigger additional requirements. The project engineer shall provide a detailed qualitative analysis of the flow path of the discharge from the project site to the receiving water. This requirement shall apply to all projects where a drainage and erosion control plan is prepared, including those proposing retention facilities. This analysis shall include flow routing, and provide existing pipe and channel sizes and estimated capacities. In addition, the project engineer shall discuss any known or expected downstream erosion, flooding, or water quality problems, including those that may be caused by inter-flow from the proposed retention facility. The director or designee shall have the discretion to specify the distance and level of detail to be provided by the project engineer. In making this determination, the director or designee shall consider such factors as the relative size of the new development, availability of other hydrologic work for the drainage area, and th extent of which stormwater generated on the project site is to be infiltrated. OK? IA *z-xomment: Page 2 of 3 Form Effective May 2009 (9) Basin Planning. Basin plan supersedes Manual. OK? c�Comment: (10) Operation and Maintenance. An operation and maintenance schedule shall be provided for all proposed stormwater facilities and BMPs, and the party (or parties) responsible for maintenance and operation shall be identified. An operation and maintenance (O&M) covenant will be required to cover all privately owned and maintained stormwater facilities approved by the director. O&M Covenant forms are available at the Mason County Public Works Office. A copy of the completed instrument shall be recorded with the Mason County Auditor's Office by the proponent and a copy of the recorded instrument is required to be submitted to the Public Works Department prior to I final approval of the completed permanent stormwater facilities. r�+��� LET OK?_VF mr nt: (� B� (11) Financial Liability. Performance bonding or other appropriate instruments shall a required for all projects to ensure compliance with these standards. OK? Comment: 01/- Are the Documents signed and stamped? ��// -�p� Type and #of License: G� 0 66d -� If not approved, what is the next action/recommendation for further action? C G d Reviewed by on Time spent in review: SECOND REVIEW/ UPDATE.- Reviewed by on Time spent in second review: THIRD REVIEW/ UPDATE: Reviewed by on Time spent in third review: Disclaimer: Mason County does not certify the quality of the work done in this Stormwater Plan. Page 3 of 3 Form Effective May 2009 Mason County Stormwater Checklist County Project # -2-c�"7 — Project Name kRl(F1�r�_ ( 4-Z 3a,1( �CZ rce-C Twnsp,Sec,Range_P Minimum Requirements of 1992 Stormwater Manual The stormwater checklist identifies the minimum requirements of the 1992 Stormwater Manual. The checklist is intended to identify the locations within the plan that addresses the minimum requirements. Mason County will not perform a technical evaluation of the submittal. Rather, the checklist provides a guide to allow Mason County to review the submittal and determine if the applicant has addressed the minimum features that make up a stormwater plan. It is incumbent upon the applicant and his/her engineer to fulfill all the applicable requirements of the 1992 Stormwater Plan as it relates to the proposed project. Review by Mason County is intended to determine if the plan has addressed the minimum requirements. Applicant's engineer shall be responsible for the technical accuracy of the submitted Stormwater plan. During construction of the project, the stormwater plan engineer of record or his/her authorized representative sha[I inspect the site to ensure the stormwater plan is being implemented as designed. Upon completion of the project, the engineer or his authorized representative shall be required to certify that the stormwater plan has been implemented as designed. Failure to meet the minimum requirements could result in delay or rejection of the application until the deficiencies are corrected. N#1: Erosion and Sediment Control. All new development and redevelopment that includes land disturbing activities of one acre or greater shall comply with erosion and sediment control requirements 1 through 14, below. Compliance with the Erosion and Sediment Control Requirements shall be demonstrated through implementation of a large parcel erosion and sediment control plan. All new development and redevelopment that includes land disturbing activities of less than one acre shall comply with the small parcel minimum requirements found in Section 14.48.140, Compliance with the small parcel requirements shall be demonstrated through implementation of a small parcel erosion and sediment control plan. Erosion and Sediment Control Requirement #1: Stabilization and Sediment Trapping. See page/paragraph ESC#l, PLAN SHEET C-2 Erosion and Sediment Control Requirement #2: Delineate Clearing and Easement Limits. ECT R ��See page/paragraph ESC#2 , PLAN SHEET C-2 j�l-+ �-+ Stormwater Checklist DOE 1992 Manual.doc 1 t. "ii 3 Updated May 20, 2009 MASON COUN Erosion and Sediment Control Requirement #3: Protection of Adjacent Properties. See page/paragraph _ESC#3 , PLAN SHEET C-2 Erosion and Sediment Control Requirement #4: Timing and Stabilization of Sediment Trapping Measures. See page/paragraph ESC#4, PLAN SHEET C-2 Erosion and Sediment Control Requirement #5: Cut and Fill Slopes. See page/paragraph ESC#5, PLAN SHEET C-2 Erosion and Sediment Control Requirement #6: Controlling Off-Site Erosion. See page/paragraph ESC#6, PLAN SHEET C-2 Erosion and Sediment Control Requirement #7: Stabilization of Temporary Conveyance Channels and Outlets. See page/paragraph ESC#7, PLAN SHEET C-2 Erosion and Sediment Control Requirement #8: Storm Drain Inlet Protection. See page/paragraph ESC#8, PLAN SHEET C-2 Erosion and Sediment Control Requirement #9: Underground Utility Construction. See page/paragraph ESC#9, PLAN SHEET C-2 Erosion and Sediment Control Requirement #10: Construction Access Routes. See page/paragraph ESC#10, PLAN SHEET C-2 Erosion and Sediment Control Requirement #11 : Removal of Temporary BMPs. See page/paragraph ESC#11, PLAN SHEET C-2 & CLEARING & EROSION CONTROL NOTE ' e. ' , PLAN SHEET C-2 Erosion and Sediment Control Requirement #12: Dewatering Construction Sites. See page/paragraph ESC#12 PLAN SHEET C-2 Erosion and Sediment Control Requirement #13: Control of Pollutants Other than Sediment on Construction Sites. See page/paragraph ESC#13 , PLAN SHEET C-2 Erosion and Sediment Control Requirement #14: Maintenance. See page/paragraph ESC#14, PLAN SHEET C-2 Erosion and Sediment Control Requirement #15: Financial Liability. See page/paragraph ESC#15, PLAN SHEET C-2 & CLEARING & EROSION CONTROL NOTE ' f . ' , SHEET C-2 0#2: Preservation of Natural Drainage Systems. Natural drainage patterns shall be maintained, and discharges from the site shall occur at the natural location to the maximum extent practicable. Seepage/paragraph DR. REP. 3 . 1 . (Existing) & 4 . f . (Proposed) Stormwater Checklist DOE 1992 Manual.doc 2 Updated May 20, 2009 #3: Source Control of Pollution. Source control BMPs shall be applied to all projects to the maximum extent practicable. Source control BMPs shall be selected, designed, and maintained according to an approved manual. See page/paragraph CONSTRUCTION: Per Checklist #1 PERMANENT: None warranted for proposed use (Office) #4: Runoff Treatment BMPs. All projects shall provide treatment of stormwater. Treatment BMPs shall be sized to capture and treat the water quality storm, defined as the six-month, twenty-four hour storm. The first priority for treatment of stormwater shall be to infiltrate as much as possible of the water quality design storm into the ground. Pretreatment of stormwater prior to infiltration into the ground may be required. See page/paragraph _ DR. REP. 4 .b. , 4 . e . , 12 .b. , Appendix C-6, 0 #5: Streambank Erosion Control. The requirement below applies only to situations where stormwater runoff is discharged directly or indirectly to a stream, and must be met in addition to meeting the requirements in minimum requirement #4, Runoff Treatment BMP's. See page/paragraph DR. REP. 4 .b. , 4 .d. , 10 .a. , Appendix C-2 N/An #6: Wetlands. Stormwater discharges to wetlands shall maintain the wetland's natural hydroperiod and flows to the extent needed to preserve or enhance its existing functions and values. Prior to proposing discharge of higher volumes of stormwater to a wetland, alternative discharge, detention, and infiltration practices located in areas outside the wetland shall be evaluated and employed by the project engineer where feasible and practicable. See page/paragraph NO DESIGN DISCHARGE TO WETLAND, OVERFLOW ONLY N/AR #7: Water Quality Sensitive Areas. Where the Mason County commissioners or their designee determine that the minimum requirements do not provide adequate protection of water quality sensitive areas, either on-site or within the basin, more stringent controls shall be required to protect water quality. An adopted and implemented basin plan (minimum requirement #9) may be used to develop requirements for water quality sensitive areas that are tailored to a specific basin. See page/paragraph _ NOT APPLICABLE P #8: Off-Site Analysis and Mitigation,. Downstream Analysis May Trigger Additional Requirements. The project engineer shall provide a detailed qualitative analysis of the flow path of the discharge from the project site to the receiving water. This requirement shall apply to all projects where a drainage and erosion control plan is prepared, including those proposing retention facilities. This analysis shall include flow routing, and provide existing pipe and channel sizes and estimated capacities. In addition, the project engineer shall discuss any known or expected downstream erosion, flooding, or water quality problems, including those that may be caused by interflow from the proposed retention facility. The Director of Public Works or designee shall have the discretion to specify the distance and level of detail to be provided by the project engineer. In making this determination, the Director of Public Works or designee shall consider such factors as the relative size of the new development, availability of other hydrologic work for the drainage area, and the extent to which stormwater generated on the project site is to be infiltrated. Stormwater Checklist DOE 1992 Manual.doc 3 Updated May 20, 2009 See page/paragraph DR. REP. 7 . N/A[]#9: Basin Planning. Basin plan supersedes Manual See page/paragraph NOT APPLICABLE X❑#10: Operation and Maintenance. An operation and maintenance schedule shall be provided for all proposed stormwater facilities and BMPs, and the party (or parties) responsible for maintenance and operation shall be identified. An operation and maintenance (OEtM) Declaration of Covenant will be required to cover all privately owned and maintained stormwater facilities. OEtM Declaration of Covenant forms are available at the Mason County Permit Assistance Center, 426 W. Cedar Street, Shelton, WA 98584. The proponent shall record a copy of the completed Declaration with the Mason County Auditors' office. A copy of the recorded document must be submitted to the Permit Assistance Center together with this completed Checklist. See page/paragraph CLEARING & EROSION CONTROL NOTE ' f. ' , PLAN SHEET C-2 I certify that the stormwater plan submitted for this project fulfills the applicable provisions of the 1992 Stormwater Manual. �4k 44-� -6C4� 07�J 43_0() 7En ' er Date -7111 App licant Date Place signed Stamp Here Poi F 02 ; 600 Stormwater Checklist DOE 1992 Manual.doc 4 Updated May 20, 2009 See page/paragraph DR. REP. 7 . N/AF] #9: Basin Planning. Basin plan supersedes Manual See page/paragraph NOT APPLICABLE 0 #10: Operation and Maintenance. An operation and maintenance schedule shall be provided for all proposed stormwater facilities and BMPs, and the party (or parties) responsible for maintenance and operation shall be identified. An operation and maintenance (OEtM) Declaration of Covenant will be required to cover all privately owned and maintained stormwater facilities. OEW Declaration of Covenant forms are available at the Mason County Permit Assistance Center, 426 W. Cedar Street, Shelton, WA 98584. The proponent shall record a copy of the completed Declaration with the Mason County Auditors' office. A copy of the recorded document must be submitted to the Permit Assistance Center together with this completed Checklist. See page/paragraph CLEARING & EROSION CONTROL NOTE ' f . ' , PLAN SHEET C-2 1 certify that the stormwater plan submitted for this project fulfills the applicable provisions of the 1992 Stormwater Manual. jqA U,,J• 02-)3- 09 Engineer Date Applicant Date Place signed Stamp Here L F 02 60 13 ti sSloxaL �� 4 A MASON COUNTY, Stormwater Checklist DOE 1992 Manual.doc 4 Updated May 20, 2009 ITEMS TO CONSIDER WHEN COMPLETING THE CHECKLIST N/AF1 Is your project in an area that is under the guidance of the Department of Ecology's 2005 Stormwater Manual (see below)? If so, you will need to use a different checklist specific to that Manual. Areas Under Guidance of 2005 Manual Year Effective Allyn and Belfair UGA (APPLICATION SUBMITTED 2007) 2008 Marine Recovery Areas/Shelton UGA June 2009 Shellfish Protection Districts June 2010 LAMIRDs Et Rural Activity Centers June 2011 All other County areas outside Designated Forest Lands June 2012 If your project is within those areas above prior to the effective year, you will need to continue to follow the guidance provided to you for the 1992 Stormwater Manual checklist. If your project is within one of the areas listed above after or during the effective year, you will need to use the 2005 Stormwater Manual checklist. If it is unclear which manual applies to your project, please consult with the Department of Community Development (360) 427-9670, ext. 352 for further determination. N/A❑ Does the drainage affect WSDOT Ditches. If Yes, contact must be made with WSDOT. N/AF1 Runoff that satisfies 1992 Manual requirements does not necessarily meet WSDOT standards for runoff into their ditchlines N/AR Is runoff affecting County or private ditches? Needs to be addressed. Q What are the impacts downstream? Are they addressed. [N Has water quality and quantity BMP's been provided as required? N/AF] Has provision been made to resize culverts if required? Have you provided calculations for basin(s) conveying to point of compliance? Have you provided calculations for stormwater features: pond sizing, conveyance systems, etc. N Does Geological Assessment/Report address stormwater features placed near slopes? N/AF] Do we need to recommend more BMP's N/A❑ Does your proposal disrupt natural drainage systems and if so what is the mitigation? Stormwater Checklist DOE 1992 Manual.doc 5 Updated May 20, 2009 Is the designer's PE Stamp and signature provided on calculations and drawings? Stormwater Checklist DOE 1992 Manual.doc Updated May 20, 2009 Michael F. Wnek, P.E. Consulting Civil Engineer 3388 NW Byron St, Suite 200, Silverdale, WA 98383 360-692-3802 (fax)-692-1051 LETTER OF TRANSMITTAL TO: RICK KRUEGER DATE: July 13, 2009 P.O. Box 548 Belfair, WA 98528 PROD. NO 444 RE: #23371 SR-3 Grading Permit GRD2007-00019 Stormwater Checklist r The following attached items, are submitted for your review. COPIES DATE NO, DESCRIPTION 3 Varies - PLANS (2 sheets) 3 06-23-08 - DRAINAGE REPORT 1 07-13-09 - Mason County Stormwater Checklist Annotated, Signed, & Stamped 1 07-13-09 - Summary of Stormwater Mitigation Plan (Attached to checklist) 1 - - O & M Declaration of Covenant (stormwater) COMMENTS. Documents for the stormwater checklist approval. Prior to submitting the documents to Mason County: • A representative of "KRUEGER PROPE�TY INVSTMNTS LLC" needs to sign page #4 of the checklist, • Similarly, the O&M Decalarion needs to be signed & notarized. If you have any questions, or need additional information, please contact me at 360-692-3802. Zk, BY: RE MICHEAL F.WNEK, P.E. MASON COUNTr cc: file - G:\CivilEng\444-Krueger\Storm\Checklist\TRANSM IT_07-13-09_RK.doc Michael F. Wnek, P.E., PS Consulting Civil Engineer 3388 NW Byron St, Suite 200, Silverdale, WA 98383, 360-692-3802 Drainage Report Revision No 1 Krueger #23371 SR-3 located in: Mason County prepared for.- Rick Krueger P.O. Box 548 Belfair, WA 98528 June 23, 2008 Project Number: 444 �^ By the seal and signature here affixed, I certify that the enclosed report was accomplished by myself, and that I am currently a registered engineer of good standingin the State of Washington, —' 9 V MASON COUNTY Krueger #2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 TABLE OF CONTENTS 1. VICINITY MAP..................................................................................................................................................................3 2. PROJECT DESCRIPTION.................................................................................................................................................3 a. Type of Permits........:......................................................................................................................................................3 b. Size and Location of Project Site....................................................................................................................................3 c. Legal Description............................................................................................................................................................3 d. Proposed Land Use..........................................................................................................................................................3 e. Proposed Site Improvements...............................................:............................................................................................3 f. Proposed Impervious Surfaces........................................................................................................................................3 g. Proposed Landscaping.....................................................................................................................................................3 3. EXISTING CONDITIONS.................................................................................................................................................3 a. Topography.....................................................................................................................................................................3 b. Land Cover......................................................................................................................................................................3 c. Land Cover/Land Use...................................................................................................................................................3 d. Offsite Drainage Onto Property.................................................................:.....................................................................4 e. Environmentally Sensitive Areas....................................................................................................................................4 f. Wells................................................................................................................................................................................4 g. Septic Systems.................................................................................................................................................................4 h. Fuel Tanks.......................................................................................................................................................................4 i. Soils.................................................................................................................................................................................4 j. Groundwater....................................................................................................................................................................4 k. Adjacent Drainage Facilities...........................................................................................................................................4 1. Drainage Discharge Points..............................................................................................................................................4 in. Relevant Reports.........................................................................................................................................................4 4. DEVELOPED SITE DRAINAGE CONDITIONS.............................................................................................................4 a. Proposed Land Cover......................................................................................................................................................4 b. Potential Storm Runoff Quantity&Quality Impacts......................................................................................................5 c. Proposed Storm Collection&Conveyance.....................................................................................................................5 d. Proposed Runoff Quantity Control..................................................................................................................................5 e. Proposed Runoff Quality Control....................................................................................................................................5 f. Discharge Point...............................................................................................................................................................5 g. Un-Mitigated Project Run-Off........................................................................................................................................5 5. WATERSHED DESCRIPTION..........................................................................................................................................5 a. Contributing Basin..........................................................................................................................................................5 b. Receiving Waters.............................................................................................................................................................5 c. Project Basins..................................................................................................................................................................5 6. DESCRIPTION OF UPSTREAM BASINS........................................................................................................................6 a. Sources of Runoff onto Project Site..............:.................................................................................................................6 b. Existing Drainage&Erosion Problems...........................................................................................................................6 7. DOWNSTREAM ANALYSIS(Level 1)............................................................................................................................6 a. Study Area.......................................................................................................................................................................6 b. Resource Information......................................................................................................................................................6 c. Field Inspection...............................................................................................................................................................6 d. USGS Map......................................................................................................................................................................6 e. Downstream Narrative.....................................................................................................................................................6 f. Structures&Channel......................................................................................................................................................6 g. Problem Areas.................................................................................................................................................................6 8. SOILS REPORT..................................................................................................................................................................6 9. GEOTECHNICAL REPORT..............................................................................................................................................6 10. HYDROLOGICAL ANALYSIS.....................................................................................................................................7 a. Infiltration Pond..............................................................................................................................................................7 b. Curve Numbers(CN)......................................................................................................................................................7 c. Time of Concentration.....................................................................................................................................................7 d. Runoff Volumes&Peak Discharges...............................................................................................................................7 e. Bypass.............................................................................................................................................................................7 11. BASIN MAPS.................................................................................................................................................................7 1 Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 12. HYDRAULIC DESIGN COMPUTATIONS....... ............... a. Piping..............................................................................................................................................................................7 b. Bioswale..........................................................................................................................................................................7 13. EROSION&SEDIMENTATION CONTROL DESIGN...............................................................................................7 a. Erosion Control Objectives.......................................................................:.....................................................................7 b. Erosion Control/Temporary Water Quality Facilities...................................................................................................7 c. Re-vegetation Plan..........................................................................................................................................................8 d. Soil Stability....................................................................................................................................................................8 e. Computations for Conveyance........................................................................................................................................8 f. Computations for Sediment Containment.......................................................................................................................8 14. MAINTENANCE&OPERATION MANUAL..............................................................................................................8 APPENDIXES VICINITY MAP A-1 PROPERTY REPORTS/TAX DESCRIPTIONS A-2 AERIAL PHOTO A-3 ASSESSORS MAP A-4 CONTOUR MAP A-5 SOILS MAP A-6 ISOPLUVIAL MAPS 3 pages) B-1 Table III—1.3 SCS Western Washington Runoff Curve Numbers B-4 Table III—1.6 Hydrologic Soil Groups for Soils in the Puget Sound Basin 2 pages) B-5 DEVELOPED BASIN EXHIBIT C-1 HYDROLOGY CALCULATIONS: INFILTRATION POND 4 pages) C-2 BIOSWALE CALCULATIONS 2 pages) C-6 2 Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 1. VICINITY MAP See attached vicinity map, Appendix page A-1. 2. PROJECT DESCRIPTION a. Type of Permits LAND MODIFICATION MASON COUNTY b. Size and Location of Project Site Parcel Size: 0.75 Acres Project Size: 0.47Acres Clearing Area: 0.47 Acres New Impervious: 0.26 Acres Location: 23371 NE STATE ROUTE 3 BELFAIR c. Legal Description Site Address: 23371 NE STATE ROUTE 3 BELFAIR Assessor's Parcel Number: 123325000009 Zoning: MU (Mixed Use) Belfair UGA d. Proposed Land Use Office building and parking e. Proposed Site Improvements New office building and paved parking. f. Proposed Impervious Surfaces Road / Roof/ SW : 0.26 acres g. Proposed Landscaping Lawn & landscaping, typical for zone. 0.11 acres 3. EXISTING CONDITIONS a. Topography The site slopes west. Maximum slopes are 15%. b. Land Cover The property is approximately 30% grass covered; the remaining is 2" growth forest. See Appendix A-3, AERIAL PHOTO. c. Land Cover/ Land Use Project property— Residential General area - Suburban Residential/ Commercial (Belfair Subarea Zoning Code) 3 Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 d. Offsite Drainage Onto Property Minor portions of the State Highway pavement flow into the project parcel. e. Environmentally Sensitive Areas Creeks, Lakes, Ponds, Wetlands — wetland, west part of parcel Ravines, Gulleys, Steep Slopes - None Springs, Env. Sensitive Areas - none The project proposes to apply a mitigated wetland buffer. See the following report prepared for this project: KRUEGER HABITAT MANAGEMENT PLAN by: THE WETLAND CORPS, September 2007 f. Wells None, parcel is on public water supply. g. Septic Systems There is one septic system located on site, which will be demolished with the residence. h. Fuel Tanks None known i. Soils Soil Conservation Service maps for the area show the soil is typically found to be Everett, belonging to the Hydrologic Group "A" g P j. Groundwater A seasonal groundwater table existing at approximately 4' below surface. k. Adjacent Drainage Facilities There are no known storm detention facilities within the stream s ro'ect u p � p basin. Downstream facilities area discussed in paragraph 7. I. Drainage Discharge Points Storm drainage from the project basin flows west to existing wetland. m. Relevant Reports None 4. DEVELOPED SITE DRAINAGE CONDITIONS a. Proposed Land Cover See 2.f. and 2.g. 4 Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 b. Potential Storm Runoff Quantity & Quality Impacts Quantity: Since the project will create greater than 5,000 square feet of impervious area, runoff quantity controls must be considered. Quality: Siltation of the storm runoff is possible during construction. Oil & sediment contamination from vehicle drippings on the access and parking areas is possible after the project is completed. Runoff quality controls are required. c. Proposed Storm Collection & Conveyance Stormwater runoff from the development will be collected and routed to the storm control facilities. Conveyance will be via pipe. d. Proposed Runoff Quantity Control Quantity control will be accomplished by an infiltration pond. The pond is designed to meet the following criteria: 100-year, 24-hr 100% infiltration 100-year, 7-day 100% infiltration e. Proposed Runoff Quality Control Water quality for the project will be accomplished by a bioswale. f. Discharge Point The project basin discharge point will be to the west location, see paragraph 3.1. In reality, this is only an overflow point, for flows beyond the infiltration pond design capacity (paragraph 4.d.). g. Un-Mitigated Project Run-Off None 5. WATERSHED DESCRIPTION a. Contributing Basin The site contributes to a larger watershed that drains westerly to the wetland area. b. Receiving Waters All runoff flows to Hood Canal c. Project Basins The developed parcel is used as the limits of the project basin. 5 Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 6. DESCRIPTION OF UPSTREAM BASINS a. Sources of Runoff onto Project Site Upstream flows are negligible, see paragraph 3.d. Upstream flows are not included in the hydrology calculations. b. Existing Drainage & Erosion Problems There are no obvious drainage or erosion problems within the project parcel or the upstream basin. 7. DOWNSTREAM ANALYSIS (Level 1) a. Study Area West side of SR-3 b. Resource Information Local Topography. c. Field Inspection A general inspection of the area was performed to confirm flow patterns in the area. d. USGS Map See attached CONTOUR MAP in Appendix A. e. Downstream Narrative The general area on the west side of SR-3 sheet flows to the wetland area with few defined drainage channels. Drainage from the wetland continues flowing west, eventually to Hood Canal. f. Structures & Channel None. g. Problem Areas There are no obvious drainage problems in the downstream area, per the field inspection. 8. SOILS REPORT None warranted. The adjacent parcel to the north was extensively explored for both storm and septic design, and generally found clean sand and gravel with interspersed silt/ clay lenses. 9. GEOTECHNICAL REPORT None warranted. 6 I Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 10. HYDROLOGICAL ANALYSIS a. Infiltration Pond The hydrological analysis is based on Santa Barbara Urban Hydrogragh methodology; using StormShed 2G software. The storm type is "1A". Facilities are designed for 100% of the 100- ear, 24-hour and 7-day peak storm event. 9 Y � Y b. Curve Numbers (CN) Everett: Group A. c. Time of Concentration Time of concentration values are calculated for existing conditions; and estimated at minimum values for developed conditions. d. Runoff Volumes & Peak Discharges See Appendix C e. Bypass All project storm runoff can be captured and routed through the treatment system. There will be no untreated runoff from the project. 11. BAS IN MAPS The project Basin Map is attached in the Appendix C. 12. HYDRAULIC DESIGN COMPUTATIONS a. Piping 8-inch piping (n=0.012 & s=1.0%) is adequate to handle the entire developed condition flow. b. Bioswale See calculations in Appendix C. 13. EROSION & SEDIMENTATION CONTROL DESIGN a. Erosion Control Objectives To prevent sediments from leaving the project site to adjacent properties or downstream channels. b. Erosion Control / Temporary Water Quality Facilities The following temporary erosion control facilities will be used for construction: Construction Entrance Interceptor Ditch & Berm Check Dams Filter Fabric Fence or Compost Berms Pipe Slope Drain 7 Krueger#2337 SR-3 MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 c. Re-vegetation Plan The pervious areas will be re-vegetated with erosion control seed mix after grading and utility construction. Final protection will be lawn & landscaping after building construction. d. Soil Stability In general, no slopes steeper than 1.5:1 will be required for the project. Gravity retaining walls may be required at some locations; walls over 4' in vertical height will require separate engineering design and building permit. e. Computations for Conveyance The types of erosion control facilities proposed for this project do not require any engineering calculations (for conveyance). f. Computations for Sediment Containment The types of erosion control facilities proposed for this project do not require any engineering calculations (for containment). 14. MAINTENANCE & OPERATION MANUAL All temporary erosion control facilities will be removed from the site at the completion of construction. The storm water features on the site will require periodic inspection and annual maintenance. An Operations & Maintenance Manual will be issued after completion of construction. s Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 VICINITY MAP NE MCKNIGNT RD Sy NE FERN WAY v u O y d m -_ z P ' NE SEnZ DR 1 tct Qo NE STATE ROUTE 300 4 W PROJECT i ( a LOCATION FI� 12�u✓ HOOD CANAL I m--q- , P. NE SQUIRE LN- Lu �o � o Vy 0 A-1 Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 number:Parcel 000009 View Map Owner Information KRUEGER, LESTER E & BETTY L 14241 E STATE HIGHWAY 106 BELFAIR WA 98528-8533 Taxpayer Information 14241 E STATE HIGHWAY 106 KRUEGER, LESTER E & BETTY L BELFAIR WA 98528-8533 Legal Description SAM B. THELER'S HOME & GAR TRS TR 4 N1/2 OF S1/2 -- Site Address ..... ..................... .__......._. .. .... 23371 NE STATE ROUTE 3 BELFAIR s Reval Area ., 12 Field Sheet FS 05309:04 Land Size* 0.75 Land Use TWO BEDROOM Tax Code 276 Tax Code Description 1 403 A P3 F2 L C H W1 Census Tract Click Here Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 AERIAL PHOTO " "Adr �i- ; e.ay a%yam . _ !, � r�4 1- sw+' •! �`! *'$ r w A IL IL IL .'\. - JL 10 � " .yam • , �G� for � �E• k t ,,.Z u� "`t x r PROJECT - '�y ` 1w IV .._ LOCATION - t ,`..` , Co - A-3 Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008. ASSESORS MAP 123294300090 123294300160 1232943001 123294300110 123293006000 1232900 123294300120 123294300140 /12-1 2 123294300250 123294300150 /123294M 123325000004 123325000003 H 123325000097 123325000008 �R04f4 1 .+tlttttatrtetttt►t tlr,z x�ttr=. HC�F/j4 123325000009 /% 1 tlttitttti:[6" r,. 123325000fl1C 123325000013 123320060000 PROJECT 123325000089 LOCATION 123325000014 �123321200010 123 t f 123325000017 123325000922 JT 123325000921 123325000019 hf 123325000016 123325000088 123325000920 OJ 123325090222 40 A. 123325090221 123325090223 12332,5000020 123325090224 123325000021 A-4 Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 USGS CONTOUR MAP —20 b4 f 1 I �E' sdl1ltt Titll Ettt itFtYltlttlt� `4' s Rllf lti!!i iiif it tiifflAtif yf t! PROJECT r ! LOCATION �o =cv ,b- r � o an /• ti~ J ?1 / 522ft A-5 Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 SOILS MAP t S m0-5 RE I' ,x g +Mw f� f .� • ` IVY V *s PROJECT LOCATION tv1. 6 . r ,s— " es .� Y Mh = Mulkiteo Eh = Everett ' 1 STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN 124 123 122 121 49 _ ' 'S _ 25 a a w wa it 3"M aj 30 is to —� - E L A' s BE it t+ LM r0 &GA I FRIDAY HARBOR PORT STA LEY n Y a rig` _ NE M7 V r40 �` � .� isR( \� 48 35302520 i /rI ERETT 45 ti PM>v5i• � m _ 3 S 45� '`� S AT w' 35.• BS r ✓ .tl \ 3 1 ! 40\ 1 —�..- 5 3 45 r " 47 3 r sys r 8 I AB DE N 30 31 25 3 s l 35 + �� •CENT + + 4 4� 20 r YANI O 56. 1O 10 3 a + 45•i a 40 ' I 1 � 35 i 'ADA 46 �� 55 45 s —— — WASNlNGTQN p 3 25 B K PPL EN E 10 0 10 20 30 40 15 MILES Figure 25 25`— NOAA ATLAS 2, Volume IX ISOFLUVIALSJF 2 YR 24 HR PRECIPITATI N IN Prepared by U.S.Department of C merce National Oceanic and Atmospheric A dministration TENTHS OF Al INCH National Weather Service,Office of Hydrology Prepared for U.S.Department of Alricuiture, Soil Conservation Service,Engineer ng Division 124 123 122 121 III-1-44 FEBRUARY, 1992 B-1 2 STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN 124 123 122 121 49 EL 1 I / s : 1 s d0 I 0 .4S I 1 r A 70 FfiIG4Y HAR CIA .PORT SIAN. •158p 3 85 .`` I 0� s r` F �7 30 / 5 i0 6 75 - ` _ T - - ,o _ 2k ,! 46 , �t 7 I1 t( 80 45 0 a 85•. I p K\ 100i 10q 5 4 e o s s yp z 1 r \ AT 5 1 IC '• 4 � 10 � I 0 2 iso 65, 00 5 S r l 7.0 if0 8 3 \47 551 3 1, j °s 5 n fH + 65 Sa 2 5 2 — 0'~ _ a s 70 d .E TR L p ,l 5 6 22 • YAKI 100 � 6ul + 45 a 55 10 .0 i 5 ' s 0 Q 45 T a 80 s m 6 7 T s 0 65 So 55 U w i e AD ME( ; 0 �25, 46_ _ s , .. -- — + s fill 4 50 40 IrKu WASHfNGTON 40 IoQ �F ! EN E 10 0 10 20 30 40 40 �; iMO MILES ( , ss$04535 �--~ Figure 30 I 1 \ NOAA ATLAS 2, Volume IX T 45 50 55 80 65 I Prepared by U.S.Department of Cairnmerce ISOPLl1VIALS F 100-YR 24-HR PRECIPIT4TION ,National Oceanic and Atmospheric ministration IN TENTHS OF N INCH National weather Service,Office of Hydrology Prepared for U.S.Department of Aculture, Soil Conservation Service,Engineer ng Division 124 123 122 121 11I-1-46 FEBRUARY, 1992 B-2 I Fiqure 5-7 , / y ,+ a DAY 3W 2W 1W 1£ 2£ 3£ 28 • 2e Kitsap County 100-YEAR 7-DAY PRECIPITATION 27 io#"@ ISOPLUVIALS OF 100—YEAR 7—DAY 27 PRECIPITATION IN INCHES 0 26 26 d 26 's v 25 .. ro �• i a 24 r A l 24 tl 7© f �J DATA y 23 23 U.S.Weather Bureau Technical Paper No.49,"Two-to-Ten-Day Precipitation for Retum Periods d 2 to I DO Years in the Contiguous p 6 United Staes" �l e.rp 22 22 3W 2W 1 W 1 E 2E 3£ REV 10/21/96 B-3 4 STORMWATER MANAGEMENT MANUAL FOR THE PUGET SOUND BASIN Table III-1.3 SCS Western Washington Runoff Curve Numbers (Published by SCS in 1982) Runoff curve numbers for selected agricultural, suburban and urban land use for Type IA rainfall distribution, 24-hour storm duration. LAND USE DESCRIPTION CURVE NUMBERS BY HYDROLOGIC SOIL GROUP A B C D Cultivated land(1): winter condition 86 91 94 95 Mountain open areas: law growing brush & grasslands 74 82 89 92 Meadow or pasture: 65 78 85 89 Wood or forest land: undisturbed 42 ; 64 76 81 Wood or forest land: young second growth or brush 55 72 81 86 Orchard: with cover crop 81 88 92 94 open spaces, lawns, parks, golf courses, cemeteries, landscaping. - Good condition: grass cover on Z75% of the 68 80 86 90 area Fair condition: grass cover on 50-75% of 77 85 90 92 the area Gravel roads & parking lots: 76 85 89 91 Dirt roads & parking lots: 72 82 87 89 _ Impervious surfaces, pavement, roofs etc. 98 98 98 98 open water bodies: lakes, wetlands, ponds etc. 100 100 100 100 Single family residential(2) : Dwelling Unit/Gross Acre %Impervious(3) Separate curve number 1.0 DU/GA 15 shall be selected for 1.5 DU/GA 20 pervious & impervious 2.0 DU/GA 25 portions of the site 2.5 DU/GA 30 or basin 3.0 DU/GA 34 3.5 DU/GA 38 4.0 DU/GA 42 4.5 DU/GA 46 5.0 DU/GA 48 5.5 DU/GA 50 6.0 DU/GA 52 6.5 DU/GA 54 7.0 DU/GA 56 PUD'e, condos, apartments, %impervious commercial businesses & must be industrial areas computed (1) For a more detailed description of agricultural land use curve numbers refer to National Engineering Handbook, Sec. 4, Hydrology, Chapter 9, August 1972. (2) Assumes roof and driveway runoff is directed into street/storm system. (3) The remaining pervious areas (lawn) are considered to be in good - condition for these curve numbers. III-1-12 FEBRUARY, 1992 B-4 v, non 0A nn nn n ooppyy ? KKK p� K a a y ^ 6' O m 7 ro ^ m s s y t O. q ? KKK (� (� i G ?' a S °•� � �' S � cam, � � 7��C"� � � — i', �a r � � : b ?: � F� �' k C' = ° •, '0, a 7 •� o a r+ b' 7CL t i^i r LH�] 0 a b x t9j M p aa x Y d a m d w ^ d w o D n w w n O a a w A Z :4 n n n o w A w a w w w n a v o o y rr Lr. v'• a' � x Y' � n � o s : m m 7� 1 T� ld �,"• c o x � � x x x x x G� 4� n n C] n m m.[A �tf a �+1 Ctii C� d C7 �7 C7 A n v' o s 5 0 0 �• c �C 3 srs = ^7 ^ .D Er o. w " Y 79 ty O m i n n O � is � ro R. m x to z w a .: na c vdwadwa0nnoit 0z0wadvmnA � wa0xvwz2: z0Dzvazdn0 > aw > 0IV > www0oa0 0Zzn � � rS O N �D i0 N _ - l 9-8 Z66T 'AdVDH9a3 OT-T-III •s�ianans 'Tog A-4unoo snoTapn pup 686T aegwegdas 'S# waoa 'paooag uoTgpgaadaequl TTOS `SOS woa; apstn suozsTnag •T-v gTgTqxg '986T aunt 'uO74Tp3 puoaaS 'SS-13Z SOS woad* •adAq TTos szgq ao; algvTlpnp ATquaaano qou pgva UN •uOTssTwSuuaq aagpM ;O aqua MOTs 1Caan u anpg aTToS asags •TETaagsw snotnaadwT Alipau nano sTTos MoTTugs pup 'aop;ans eqq aEau ao qu aeAvT ApTo ao uudpapq p gqTM sTTos 'OTgpq aagEM gbTq quaupwaad p gqTM sTTos 'T2T4ua4od buTTTaMs gbTq e gqTM altos ARTo ;o ACT;aTgo buTgsTsuoo pus pagqaM ATgbnoaogq Uagm sagpa UOTgpagTT;UT MOTs Alan buTnpq aTToS • (TRTquagod ;;ounce g61H) •Q •UOTasTwsusaq aagsM ;o agsa MOTs u ansq sTTos asagy •saangxaq auT; oq auT; ATagpaapow gqTM sTTos ao 'aagsM ;o quawanow pavMUMop sapadluT gsgq aaAVT e gqTM STTOB ;o Al;eTgo buTgaTauOo pus 'pagqeM Algbnoaogq uagM aagea UOjgpagTT;uT MOTS bUTnsg STTOS • (TETquagod ;;ounce g6Tq bTaquaapoH) •0 •UO788Twsupa4 aegpM ;o aqua agpaapow a anpq sTTos esagy •SaAngxaq asaeoo ATagpaapow oq auT; ATagpaapow ;o AT;aTgo buTgsTsuoo pup 'pagqeM ATgbnoaogq uagM sagsa UOTIP-14 UT agpaapow buTnpq sTToS • (TPlquagod ;;ounce MOT .ilagsaapoH) •g •uoTssTmauEaq aagpM ;o aqua gbTq E anpq sTToS asagy •slanpab ao apupS pauTeap ATanTssaoxa-oq-TTaM 'deap ;0 AT;aTgo buTgsTsuoo pup 'pagqaM ATgbnoaogq uagM uana 'sagpa UOTgeagTT;uT gbtq buTnpq aTToS • (TETquagod ;;ounce Mo'I) •v suOT4p0T;T9seTO dnoao TTOS oT60101PAH fl iogu,(z aN paa� wlaA fl tg8nvg fl 2111nu!P00M V uog6u!M 8 �v[18vg fl uosoll!M ON auoapno ON C:gp!glA (IN Inaona a UVIVAl fl dnllukrtd dN ogvdvA{ a 128nd J tolsan J squid 8 ucal!vn ' oqulnod algvuvn uvgjn 0 qng74ca QN (aln L 0 31angol!d O vT!AgrLj. aN uvlogd (IN uoiut J (aoaagd 0 pu0s"01 J II!pvd ON Moi. J 11VA0 Q gas!y J oso J ou!u;.JL ON 8u!UO QN IT greTvojL a v!P!IO ON xvMuvy CI vvwp 0 woavd, 9 aldzuAl0 (IN umomms 0 wM0010 J vvwns QN cn210 a IUWUVA uv1TnS J CtivBp 0 uvtlns Q/J euuol,( fl Jvnvelns O llavnlool,T fl 2Tvp8uud3 8 kllmbs!N 81V CvMvugds fl SaagnwN dnwrJ *(Ul1!os dncjE) adCi I!oS llos a!BoIwP�H Ilos 3!80]-PAH NISVE GNQOS 130fld 3H,1 Hoa lVfINVW ZNaWaDVNVW HajVMM0jS 9 � o � m c m FT1 / / / / / / p w rrTv/ // % / / / Z cn 03 u, _/6'HIDE�2F7'FNtCTING ------ SRLLWA/ ow+ftiow SPuwAr — /r WIT C-2 ST pow ;00D SWAM Not 35 — —__ / // � � %,ate/ � : fD ?I ol / I / 1w / / O .in / / N co ch Krueger#23371 SR MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 Precipitation Event Precip (in) 6 month 2.2400 2 year 3.5000 100 year 7.0000 7 day 14.0000 LPOOL SUMMARY using Puls Start of live storage: 100.0000 ft Event Match Q (cfs) Peak Q (cfs) Peak Stg (ft) Vol (cf) Vol (acft) Time to Empty 2 year 0.2157 0.0629 101.4275 632.78 0.0145 25.67 100 year 0.4906 0.1183 102.9453 1996.03 0.0458 30.00 7 day 0.2067 0.0906 102.2444 1262.63 0.0290 169.33 BASIN SUMMARY BasinID Event Peak Q Peak T Peak Vol Area Method/Loss Raintype (cfs) (hrs) (ac-cf) (ac) DEVELOPED 2 year 0.2157 8.00 0.0779 0.37 SBUH/SCS TYPEIA DEVELOPED 100 year 0.4906 8.00 0.1755 0.37 SBUH/SCS TYPEIA DEVELOPED-7 7 day 0.2067 55.00 0.3515 0.37 SCS/SCS KC7DAY day HYDROGRAPH SUMMARY HydID Peak Q (cfs) Peak T (hrs) Peak Vol (ac-ft) Cont Area (ac) 2 year out 0.0629 9.33 0.0779 0.3660 100 year out 0.1183 10.17 0.1755 0.3660 7 day out 0.0906 56.00 0.3514 0.3660 C-2 Krueger#23371 SR MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 Record Id: DEVELOPED Design Method SBUH Rainfall type TYPEIA Hyd Intv 10.00 min Peaking Factor 484.00 Abstraction Coeff 0.20 Pervious Area (AMC 2) 0.11 ac DCIA 0.26 ac Pervious CN 68.00 DC CN 98.00 Pervious TC 10.00 min DC TC 5.00 min Pervious CN Cale Description SubArea Sub en Open spaces, lawns,parks (>75% grass) 0.11 ac 68.00 Pervious Composited CN (AMC 2) 68.00 Pervious TC Cale Type Description Length Slope Coeff Misc TT Fixed 10.00 min Pervious TC 10.00 min Directly Connected CN Cale Description SubArea Sub en Roof 0.06 ac 98.00 Parking 0.20 ac 98.00 DC Composited CN (AMC 2) 98.00 Directly Connected TC Cale Type Description Length Slope Coeff Misc TT Fixed 5.00 min Directly Connected TC 5.00min C-3 Krueger#23371 SR MICHAEL F. WNEK, P.E. PS Drainage Report May 30, 2008 Record Id: DEVELOPED-7 day Design Method SCS Rainfall type KC7DAY Hyd Intv 10.00 min Peaking Factor 484.00 Abstraction Coeff 0.20 Pervious Area (AMC 2) 0.11 ac DCIA 0.26 ac Pervious CN 52.00 DC CN 96.00 Pervious TC 10.00 min DC TC 5.00 min Pervious CN Calc Description SubArea Sub cn Open spaces, lawns,parks (>75% grass) 0.11 ac 52.00 Pervious Composited CN (AMC 2) 52.00 Pervious TC Calc Type Description Length Slope Coeff Misc TT Fixed 10.00 min Pervious TC 10.00 min Directly Connected CN Calc Description SubArea Sub cn Roof 0.06 ac 96.00 Parking 0.20 ac 96.00 DC Composited CN (AMC 2) 96.00 Directly Connected TC Calc Type Description Length Slope Coeff Misc TT Fixed 5.00 min Directly Connected TC 5.00min CURVE NUMBER CONVERSION 0.1549*CN24-hoar+0.8451 * ((CN24-ho.r^2.365/631.8)+ CN,-da,,= 15) 24—HOUR VALUE 7—DA Y VALUE CN24-hoar= 68 CN7_da,= 52 CN24-hoar= 98 CND-day= 96 C-4 Krueger#23371 SR MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 Record Id: LPOOL Descrip: Prototype Record Increment 0.10 ft Start El. 100.0000 ft Max El. 104.0000 ft Storage Node INFIL POND Discharge Node INFILTRATION Record Id: INFIL POND Record Id: INFILTRATION Descri Record Increment 0.10 ft Prototype P� Prototype h'P Descrip: Structure Increment 0.10 ft Start El. 100.0000 ft Max El. 104.0000 ft 104.0000 Length 21.0000 ft Width 13.0000 ft Start El. 100.0000 ft Max El. ft Length ss1 3.00h:Iv Length ss2 3.0000h:Iv Infiltration WP Multiplier 1.00 .Width ss 1 3.00h:l v Width ss2 3.0000h:1 v rate 4.1350 in/hr Multi P Stage Storage Rating Curve Stage Discharge Rating Curve I00.0000 ft 0.0000 cf 102.1000 ft 1134.2520 cf I00.0000 ft 0.0000 cfs 102.1000 ft 0.0854 cfs 100.1000 ft 28.3320 cf 102.2000 ft 1222.0560 cf 100.1000 ft 0.0282 cfs 102.2000 ft 0.0890 cfs 100.2000 ft 58.7760 cf 102.3000 ft 1313.4840 cf 100.2000 ft 0.0304 cfs 102.3000 ft 0.0927 cfs 100.3000 ft 91.4040 cf 102.4000 ft 1408.6080 cf 100.3000 ft 0.0326 cfs 102.4000 ft 0.0965 cfs 100.4000 ft 126.2880 cf 102.5000 ft 1507.5000 cf 100.4000 ft 0.0349 cfs 102.5000 ft 0.1003 cfs 100.5000 ft 163.5000 cf 102.6000 ft 1610.2320 cf 100.5000 ft 0.0373 cfs 102.6000 ft 0.1042 cfs 100.6000 ft 203.1120 cf 102.7000 ft 1716.8760 cf 100.6000 ft 0.0398 cfs 102.7000 ft 0.1082 cfs 100.7000 ft 245.1960 cf 102.8000 ft 1827.5040 cf 100.7000 ft 0.0423 cfs 102.8000 ft 0.1122 cfs 100.8000 ft 289.8240 cf 102.9000 ft 1942.1880 cf 100.8000 ft 0.0449 cfs 102.9000 ft 0.1164 cfs 100.9000 ft 337.0680 cf 103.0000 ft'2061.0000 cf 100.9000 ft 0.0476 cfs 103.0000 ft 0.1206 cfs 101.0000 ft 387.0000 cf 103.1000 ft 2184.0120 cf 101.0000 ft 0.0503 cfs 103.1000 ft 0.1248 cfs 101.1000 ft 439.6920 cf 103.2000 ft 2311.2960 cf 101.1000 ft 0.0532 cfs 103.2000 ft 0.1292 cfs 10 1.2000 ft 495.2160 cf 103.3000 ft 2442.9240 cf 101.2000 ft 0.0561 cfs 103.3000 ft 0.1336 cfs 101.3000 ft 553.6440 cf 103.4000 ft 2578.9680 cf 101.3000 ft 0.0590 cfs 103.4000 ft 0.1381 cfs 101.4000 ft 615.0480 cf 103.5000 ft 2719.5000 cf 101.4000 ft 0.0621 cfs 103.5000 ft 0.1427 cfs 10 1.5000 ft 679.5000 cf 103.6000 ft'2864.5920 cf 101.5000 ft 0.0652 cfs 103.6000 ft 0.1473 cfs 01.6000 ft 747.0720 cf 103.7000 ft 3014.3160 cf 101.6000 ft 0.0684 cfs 103.7000 ft 0.1520 cfs 101.7000 ft 817.8360 cf 103.8000 ft 3168.7440 cf 101.7000 ft 0.0716 cfs 103.8000 ft 0.1568 cfs 101.8000 ft 891.8640 cf 103.9000 ft 3327.9480 cf 101.8000 ft 0.0749 cfs 103.9000 ft 0.1616 cfs 101.9000 ft 969.2280 cf 104.0000 ft 3492.0000 cf 101.9000 ft 0.0784 cfs 104.0000 ft 0.1666 cfs 102.0000 ft 1050.0000 cf 104.1000 ft 3660.9720 cf 102.0000 ft 0.0818 cfs 104.1000 ft 0.1716 cfs 104.0000 ft 0.1666 cfs C-5 Krueger#23371 SR MICHAEL F. WNEK, P.E., PS Drainage Report May 30, 2008 Record Id: STG-STORAGE Descrip: lPrototype Record Increment(0.10 ft Start El. 130.0000 ft Max El. 34.0000 ft' Stage Area -Stage(ft) Area(sf) 30.00 329.6800 34.00 1544.3900 Stage Storage Rating Curve 30.0000 ft F 0.0000 cf 32.1000 ft 1361.9369 cf 30.1000 ft 34.4864 cf 32.2000 ft 11460.1956 cf 30.2000 ft F72.0096cf 32.3000 ft 1561.4910 cf 30.3000 ft 112.5695 cf 32.4000 ft 1665.8232 cf 30.4000 ft 156.1662 cf 32.5000 ft 1773.1 221 cf 30.5000 ft 1202.7997 cf 32.6000 ft 1883. 9979 cf 30.6000 ft F252.4699 cf 32.7000 ft 1997.0405 cf 30.7000 ft F305.1770cf 32.8000 ft 21,13.5198 cf 30.8000 ft F360.9208 cf 32.9000 ft 2233.0359 cf 30.9000 ft 419.7014 cf 33.0000 ft 2355.5889 cf 31.0000 ft F481.5187cf 33.1000 ft 2481.1785 cf 31.1000 ft 546� 3729 cf 33.2000 ft 2609.8047 cf 31.2000 ft 614.2638 cf 33.3000 ft 2741.4680 cf 31.3000 ft 685.1915 cf 33.4000 ft 2876.1680 cf 31.4000 ft 759.1559 cf 33.5000 ft 3013.9048 cf 31.5000 ft 836.1572 cf 33.6000 ft 3154.6 882 cf, F3-1.6000 ft 916.1952 cf 33.7000 ft 3298.4885 cf j31.7000 ft 999. 072 0 cf 33.8000 ft 3445.3354 cf F1.8000 ft 11085.3816 cf 33.9000 ft 3595.2195 cf F31.9000 ft 1174. 2299 cf 34.0000 ft 3748.1399 cf C-6 Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 BIOSWALE 6-month TRAPEZOIDAL CHANNEL ANALYSIS RATING CURVE COMPUTATION April 17, 2008 PROGRAM INPUT DATA DESCRIPTION VALUE -------------------------------------------------------------------------------- Channel Bottom Slope (ft/ft) . ...... .... . ... .. .... . . ..... ... . 0.02 Manning's Roughness Coefficient (n-value) . ... .... . ......... . 0.07 Channel Left Side Slope (horizontal/vertical) .. .......... ... 3.0 Channel Right Side Slope (horizontal/vertical) .... . .... .... . 3.0 Channel Bottom Width (ft) ............. .......... ......... ... 1.0 Minimum Flow Depth (ft) .. . . . ....... ... . . ... .. ... . . . ........ . 0.12 Maximum Flow Depth (ft) . . ....... .... . .... . .. . ... .......... . . 0.22 Incremental Head (ft) .......... . ... . ... . . ..... ..... ...... ... 0.01 COMPUTATION RESULTS Flow Flow Flow Froude Velocity Energy Flow Top Depth Rate Velocity Number Head Head Area Width (ft) (cfs) (fps) (ft) (ft) (sq ft) (ft) -------------------------------------------------------------------------------- 0.12 0.1 0.615 0.3521 0.0059 0.1259 0.163 1.72 0.13 0.116 0.643 0.3559 0.0064 0.1364 0.181 1.78 0.14 0.133 0.67 0.3594 0.007 0.147 0.199 1.84 --> 0.15 0.151 0.696 0.3626 0.0075 0.1575 0.218 1.9 0.16 0.171 0.721 0.3657 0.0081 0.1681 0.237 1.96 0.17 0.191 0.745 0.3686 0.0086 0.1786 0.257 2.02 0.18 0.213 0.769 0.3713 0.0092 0.1892 0.277 2.08 0.19 0.236 0.792 0.3739 0.0097 0.1997 0.298 2.14 0.2 0.261 0.814 0.3764 0.0103 0.2103 0.32 2.2 0.21 0.286 0.836 0.3788 0.0109 0.2209 0.342 2.26 0.22 0.313 0.858 0.3811 0.0114 0.2314 0.365 2.32 HYDROCALC Hydraulics for Windows, Version 1.2a Copyright (c) 1996 Dodson & Associates, Inc., 5629 FM 1960 West, Suite 314, Houston, TX 77069 Phone: (281)440-3787, Fax: (281)440-4742, Email:software@dodson-hydro.com All Rights Reserved. Q6-month = 0. 1427 CfS 200 LF NOT AVAILABLE @ 50 LF (25% of LENGTH) USE 4-FT BOTTOM WIDTH C-6 Krueger Michael F. Wnek, P.E., PS Drainage Report May 30, 2008 BIOSWALE HYDRAULICS 100-YEAR FLOW TRAPEZOIDAL CHANNEL ANALYSIS RATING CURVE COMPUTATION April 17, 2008 PROGRAM INPUT DATA DESCRIPTION VALUE -------------------------------------------------------------------------------- Channel Bottom Slope (ft/ft) ................................ 0.02 Manning's Roughness Coefficient (n-value) ................... 0.035 Channel Left Side Slope (horizontal/vertical) ............... 3.0 Channel Right Side Slope (horizontal/vertical) .............. 3.0 Channel Bottom Width (ft) ................................... 1.0 Minimum Flow Depth (ft) ..................................... 0.18 Maximum Flow Depth (ft) ..................................... 0.28 Incremental Head (ft) ....................................... 0.01 COMPUTATION RESULTS Flow Flow Flow Froude Velocity Energy Flow Top Depth Rate Velocity Number Head Head Area Width (ft) (cfs) (fps) (ft) (ft) (sq ft) (ft) -------------------------------------------------------------------------------- 0.18 0.426 1.538 0.7426 0.0368 0.2168 0.277 2.08 0.19 0.472 1.584 0.7479 0.039 0.229 0.298 2.14 0.2 0.521 1.629 0.7529 0.0412 0.2412 0.32 2.2 0.21 0.573 1.673 0.7576 0.0435 0.2535 0.342 2.26 --> .0.22 0.626 1.715 0.7622 0.0457 0.2657 0.365 2.32 0.23 0.683 1.757 0.7666 0.048 0.278 0.389 2.38 0.24 0.742 1.798 0.7709 0.0503 0.2903 0.413 2.44 0.25 0.805 1.839 0.7749 0.0525 0.3025 0.438 2.5 0.26 0.869 1.879 0.7789 0.0548 0.3148 0.463 2.56 0.27 0.937 1.918 0.7827 0.0571 0.3271 0.489 2.62 0.28 1.008 1.956 0.7864 0.0594 0.3394 0.515 2.68 HYDROCALC Hydraulics for Windows, Version 1.2a Copyright (c) 1996 Dodson & Associates, Inc., 5629 FM 1960 West, Suite 314, Houston, TX 77069 Phone: (281)440-3787, Fax: (281)440-4742, Email:software@dodson-hydro.com All Rights Reserved. Q100-year = 0.5881 C f S C-7 i