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Agenda 05/12/2009 Item #16B 8 Agenda Item No. 16B8 May 12, 2009 Page 1 of 25 ~ EXECUTIVE SUMMARY Recommendation to approve submitting a Section 319 Nonpoint Source Management Program grant application to the Florida Department of Environmental Protection (FDEP) in the amount of $721,737 to construct the Griffin Road Stormwater Improvement Project. OBJECTIVE: To approve submitting a Section 319 grant application to the Florida Department of Environmental Protection (FDEP) in the amount of$721,737 to construct the Griffin Road Stormwater Improvement Project. CONSIDERA TIONS: The FDEP has solicited applications for grant funds available through Section 319(h) of the Federal Clean Water Act. The grant funds can be used to implement projects or programs that will help to reduce nonpoint sources of pollution. The deadline to submit the application is May 22, 2009. The attached proposed application is subject to further revisions as required by the grant guidance. The Proposed Griffin Road Stormwater Improvemcnt Project is located near the southwestern terminus of Griffin Road in southwestern Collier County off of US 41 Tamiami Trail and Barefoot Williams Road. The project will be constructed on Rookery Bay National Estuarine Research Reserve property, The focus of the project is to provide water quality treatment facilities and reduce flooding in the area. The project includes rcplacing a system of ditches and a small canal with a lake and filter marsh that will enhance water quality treatment and reduce point sourcc discharge. This project is a collaborative effort between Rookery Bay National Estuarine Rcsearch Reserve and Collier County, with Collier County playing the lead role in dcsigning, pennitting, managing the project construction and grant management. Currently, the outfall for the drainage basin that will be served by the proposed project consists of a system of ditches and swales constructed to drain the area with little concern for water quality or quantity discharges. There exist few detcntion facilities within the drainage basin, The existing drainage system relies on ditches and culverts that are currently maintained by homeowner associations or Collier County. Thcse ditches and one small canal discharge to Rookery Bay partially as a point source discharge to Hcnderson Creek within Rookery Bay National Estuarine Research Reserve. Discharge also occurs through an abandoned system of ditches and swales on Rookery Bay National Estuarine Research Reserve property that were previously used for agriculture. The point source discharge was eliminated by construction of a private development in accordance with permit conditions. The old farming ditches are now overgrown and are not perfom1ing as an adequate stormwater outfall for the area. ~ As a result, the arca has increasingly experienced poor drainage. This project seeks to establish a reliable water quality treatment facility and a drainage outfall by replacing the old system, constructed prior to current water managcment regulations, with new facilities constructed in accordance with current design technology utilizing best management Agenda Item No. 1668 May 12, 2009 Page 2 of 25 practices. The desire is to supplcment the elimination of the point source discharge with detention facilities and controlled discharge facilities, The project is expected to result in a net benefit in water quality by constructing a lake and filter marsh that will provide water quality treatment. Furthermore, the project will entail constructing a control structure in the form of a long broad crested weir that will control stormwater discharges to Rookery Bay National Estuarine Research Reserve. This combination of stormwater facilities will replace the existing uncontrolled discharge to Rookery Bay National Estuarine Research Reserve. Finally, this project should provide diverse open fresh water habitat and marsh habitat that will be integrated into the natural uplard and estuarine transitional areas within the subject property. The completed project should provide opportunities to further study water quality treatment best management practices ard marsh creation as a means to control and treat discharges from older developed areas, FISCAL IMPACT: The total cstimated project cost is $ ] ,202,895 of which a non- federal 40% match is required, which equates to $ 481,158, Of this match requirement, $ 46,895.00 will be met with in kind staff time. Construction cost for the project will be budgeted in the Stonnwater Capital Projects Fund, Fund 325, in Fiscal Year 20 II. The source of funding is ad valorem taxes. LEGAL CONSIDERATIONS: This item has been reviewed and approved by the County Attorney's Office, is not quasi-judicial and requires no ex parte disclosure, requires only a majority vote for approval, and is otherwise legally sufficient for Board action.-SRT GROWTH MANAGEMENT IMPACT: The Griffin Road Stormwater Improvement Project is in accordance with the goals and objectives of the Drainage Sub-element of the Growth Management Plan for Collier County Storm water Management. RECOMMENDATION: Recommendation that the Board of County Commissioners (I) approve submittal of the grant application to the Florida Department of Environmental Protection for the Section 319 Nonpoint Source Management Grant Program for $72],737 for stormwater improvements to the Griffin Road area; and (2) to authOlize the chair to sign the transmittal letter and all associated grant application documents. Prepared by: Brandy Otero, Operations Analyst, Stormwater Management Attachments: (I) Trarsmittal Letter; (2) Grant Application Page 1 of2 Agenda Item No. 16B8 May 12, 2009 Page 3 of 25 COLLIER COUNTY BOARD OF COUNTY COMMISSIONERS Item Number: Item Summary: 1688 Meeting Date: Recommendation to approve submitting a Section 319 Nonpoint Source Management Program grant application to the Florida Department of Environmental Protection (FDEP) in the amount of $721 ,737 to construct the Griffin Road Stormwater Improvement Project. 5/12/2009 900:00 AM Prepared By Brandy Otero Transportation Services Planning Tech Transportation Planning Date 4/27/20094:51 :52 PM Approved By Norm E. Feder, Alep Transportation Division Administrator Transportation Services Admin. Date 4/28/2009 1 :31 PM Transportation Services Approved By Caroline Soto Administrative Assistant Date Transportation Services Transportation Engineering and Construction 4/28/2009 1 :39 PM Approved By Marlene J. Foord Grants Coordinator Date Administrative Services Administrative Services Admin. 4/29/20099:28 AM Approved By John Vliet Roads Maintenance Superintendant Date Transportation Services Road Maintenance 4/29/20099:49 AM Approved By Gerald Kurtz Senior Engineer Date Transportation Services Stormwater Management 4/29/2009 1:47PM Approved By Scott R. Teach County Attorney Assistant County Attorney County Attorney Office Date 4/29/20092:04 PM Approved By Jeff Klatzkow County Attorney County Attorney County Attorney Office Date 5/1/200910:03 AM Approved By Lisa Taylor Management/Budget Analyst Date Transportation Services Transportation Administration 5/1/2009 1 :27 PM ApprovL-d By Pat Lehnhard Executive Secretary Transportation Services Admin Date Transportation Services 5/1/2009 1 :36 PM Approved By Susan Usher Senior Management/Budget Analyst Date file://C:\AgendaTest\ExP0l1\ 1 29-Mav%20 12.%202009\ 16,%20CONSENT%20AGENDA \ 16... 5/1i/2009 County Manager's Office Page 2 of2 Agenda Item No. 1688 May 12, 2009 Page 4 of 25 Office of Management & Budget 515120097:59 AM Approved By Leo E. OChs, Jr. Board of County Commissioners Deputy County Manager Date County Manager's Office 515120099:33 AM file://C:IAgendaTestIExportI129-May%20 12.%2020091 16,%20CONSENT%20AGENDA 116... 5/6/2009 Agenda Item No. 16B8 May 12, 2009 Page 5 of 25 May 12, 2009 Ms. Holly Powless Florida Department of Environmental Protection NPS Management Section 2600 Blair Stone Road, MS 3570 Tallahassee, Florida 32399-2400 Re: Section Grant Program Dear Ms. Powless On behalf of Collier County, I am pleased to submit the enclosed grant application (three paper copies and one electronic version) to the Florida Department of Environmental Protection, NPS Management Section for the Section 319 Grant Program. If the Collier County Griffin Road Stormwater Improvement project is selected for funding, Collier County is committed to fulfilling all commitments made in the grant application, including provision of the local match. We look forward to working with you on this very important project for Collier County. Sincerely, Donna Fiala Chairman Agenda Item No. 16B8 May 12, 2009 Page 6 of 25 FY 2010 SECTION 319 GRANT PROPOSAL APPLICATION PROJECT: GRIFFIN ROAD STORMWATER IMPROVEMENT PROJECT PROJECT FUNDING: $721,737 FY10319 $481,158 Match LEAD ORGANIZATION: Collier County Transportation Department, Stormwater Management CONTACT PERSON: Brandy Otero, Operation's Analyst (Name, Address, Phone) COOPERATING ORGANIZATIONS: Rookery Bay National Estuarine Research Reserve, Friends of Rookery Bay, South Florida Water Management District Big Cypress Basin Board, Griffin Road Homeowner's Association. PROJECT ABSTRACT: The Proposed Griffin Road Stormwater Improvement Project is located near the southwestern terminus of Griffin Road in southwestern Collier County off of US41 Tamiami Trail and Barefoot Williams Road. The project will be constructed on Rookery Bay National Estuarine Research Reserve property. The focus of the project is to provide water quality treatment facilities and to replace a system of ditches and a small canal that provide for a drainage outfall to the stormwater basin with new regulated drainage facilities. These facilities will serve older established neighborhoods that were constructed prior to the current water management regulatory environment. The project is a collaborative effort between Rookery Bay National Estuarine Research Reserve, South Florida Water Management District, Big Cypress Basin, Griffin Road Homeowner's Association and Collier County. Collier County will be playing the lead role in the project by providing project management and commissioning the design and permitting services for the project. Rookery Bay National Estuarine Research Reserve will be providing the land and will also be providing eCOlogy services for the project. South Florida Water Management district, Big Cypress Basin will be providing technical and permitting support and the Griffin Road Homeowner's Association and Friends of Rookery Bay will be providing support and stakeholder input Currently, the outfall for the drainage basin that will be served by the proposed project consists of a system of ditches and swales constructed to drain the area with little concern for water quality or quantity discharges, There are few detention faculties within the drainage basin. The existing drainage system relies on ditches and culverts that are currently maintained by homeowner associations or Collier County. These ditches and one small canal discharge to Rookery Bay partially as a point source discharge to Henderson Creek within Rookery Bay National Estuarine Research Reserve. Discharge also occurs through an abandoned system of ditches and swales on Rookery Bay National Estuarine Research Reserve property that were previously used for agriculture. The point source discharge was eliminated by construction of a private development in accordance with permit conditions. The old farming ditches are now overgrown and are not performing as an adequate stormwater outfall for the area, As a result the area has increasingly experienced poor drainage. This project seeks to establish a reliable water quality treatment faCility and a drainage outfall by replacing the old system constructed prior to current water management regulations with new facilities constructed in accordance with current design technology utilizing best management practices, The desire is to supplement the elimination of the point source discharge with detention facilities and controlled 1 Agenda item No. 16B8 May 12, 2009 Page 7 of 25 discharge facilities. The project is expected to result in a net benefit in water quality by constructing a lake and filter marsh that will provide water quality treatment Furthermore the project will entail constructing a control structure in the form of a long broad crested weir that will control stormwater discharges to Rookery Bay National Estuarine Research Reserve. This combination of stormwater facilities will replace the existing uncontrolled discharge to Rookery Bay National Estuarine Research Reserve, Finally this project should provide diverse open fresh water habitat and marsh habitat that will be integrated into the natural upland and estuarine transitional areas within the subject property. The elimination of exotic vegetation within the project area will also be undertaken, The completed project should provide opportunities to further study water quality treatment best management practices and marsh creation as a means to control and treat discharges from older developed areas. PROJECT LOCATION AND WATERSHED CHARACTERISTICS: The project location is depicted in the attached Figure 1: Site Locator Map and is iocated within the limits of Collier County District 6 and the Lely Area Stormwater Improvement Plan. As a result the project is consistent with Section 319 funds target objectives which state that the funds will be targeted first to watersheds with a comprehensive watershed plan, The receiving water bodies are listed as impaired by FDEP (Coastal Rookery Bay) and EPA (Henderson Creek) but TMDL limitations have not been established for the receiving water bodies, The location is environmentally strategic in that the project is situated along the interface between existing and ongoing urban development and sensitive natural lands designated as a national research reserve. The project location is within the limits of Rookery Bay National Estuarine Research Reserve. The water treatment facilities will be located in an impacted area which was previously used for row crop farming. As a result, the construction of the facility will be in already impacted areas and post construction habitat will include open water and wetland habitats which will result in a net improvement to the watershed habitat The watershed can be generally characterized as an urban fringe to urban watershed with a variety of land uses. The watershed contains estate sized lots of rural character with no water management or treatment facilities, The estate size lots are used for residential habitations, ornamental horticultural and agricultural land uses. Much of the development within the basin was constructed prior to the implementation of the current water management regulations. As a result volume discharge and water quality discharge are largely not managed and the design criteria was primarily provide adequate drainage, There is a portion of the watershed that contains master planned communities with and without golf course amenities. There are commercial iand uses which are highly impervious. Travel trailer recreation and manufactured homes are also located in the watershed and these development areas are highly impervious and do not contain adequate water quality and volumetric discharge attenuation facilities. Finally a portion of the basin has been deveioped in accordance with current water management regulatory controls. Watershed Name: Collier County District 6 Latitude: 81 43' 21" Longitude: 26 03' 06" Hydrologic Unit Code(HUC): 03090204 2 ,4genda Item No. 16B8 May 12, 2009 Page 8 of 25 Land Uses within the Watershed (acres and percentages of total): Acres 106.9 176.5 69.4 12.1 369.4 % 29.3 48.4 19.0 3.3 100 POLLUTION REDUCTION STRATEGY: The pollution reduction strategy includes the implementation of structural and non structural best management practices that will improve the basin water quality and quantity discharge characteristics. The structural best management practices include the construction of forty acres of lake and created wetlands constructed on land disturbed as part of an abandoned agricultural land use. in addition, the lake discharge will be controlled through the construction of a multiple hundred foot broad crested weir designed to produce sheet flow discharge at less than one foot per second discharge velocity. The lake and filter marsh will provide approximately 12,960,000 CF of volumetric water quality treatment. PROJECT OBJECTIVE(S): The project objectives are as follows. . Eliminate a historic man made point source discharge which is responsible for lowering water tables in the area during the dry season and promoting unnatural point source discharges during the wet season. . Collect untreated stormwater discharges from unregulated developments and provide for volumetric storage and water quality treatment. . Provide discharge controls for quantity discharges from unregulated land. . Provide for salt water barrier to prevent saline water intrusion into fresh ground water regime. . Provide for future research opportunities to measure level of treatment and establish useful treatment mechanisms for urban-natural system Interface areas. . Restore native habitat in an area that has been disturbed by agricultural activities in the past and now harbors exotic vegetation and the resulting seed source for further exotic vegetation proliferation. PROJECT DESCRIPTION: The project consists of a forty acre lake and created marsh that will provide water quality treatment and volumetric storage for the drainage basin identified in the attached exhibits. The project also includes improvements to existing ditches that will feed the lake and filter marsh with stormwater discharges for the drainage basin. Finally the project includes a public education component and urban runoff management and control plan. 3 Agenda Item No. 16B8 May 12, 2009 Page 9 of 25 ESTIMATED POLLUTANT LOAD REDUCTION: BMPs Installed Other Other TSS TP TN Sediment BOD ka/vr kalvr kglyr kglyr kg/yr kglyr kg/yr . Pre-Project 223.1 1274.9 "0 . 0 Post. Project 46.5 713.6 ..J 1: Load . 176.6 561.3 :2 Reduction "0 Q. % Reduction 79.2 44 Other Other TOTAL TSS TP TN Sediment BOD ka/vr ka/vr kg/yr kg/yr kg/yr kg/yr kglyr . Pre-Project 223.1 1274.9 "0 . 0 Post-Project 46.5 713.6 ..J - 0 Load .l!I 176.6 561.3 -= Reduction "0 Q. % Reduction 79.2 44 MODEL USED: Harvey Harper for Phosphate and Nitrogen and STEPL for suspended solids biological oxygen demand and dissolved oxygen. LAND OWNERSHIP STATUS: Rookery Bay National Estuarine Research Reserve Florida Department of Environmental Protection. Rookery Bay National Estuarine Research Reserve and the Florida Department of Environmental Protection will be granting a drainage easement for proposed activities as part of the project. A draft application for the easement is attached. OUTPUTS/DELlVERABLES: The ultimate goal of the project is to design, permit, and construct the Filter Marsh as outlined in the descriptions above, The following is a description of the tasks needed to accomplish the goal. Task 1 - Construction Plans and Permitting: This project is currently being designed and permitted. Necessary permits will be obtained prior to construction. Consultant engineering services will be required during construction to ensure that construction plans and speCifications are followed. Task 2 - Public Involvement: A minimum of two public information meetings will be conducted to inform the public and solicit comments from residents in the area. These meetings will be used to educate the public in stormwater best management practices. Task 3 - Construction: Construction of the Griffin Road Stormwater Improvement Project will begin after all necessary permits have been received. Collier County and Rookery Bay National Estuarine Research Reserve will provide project management and inspection to ensure that improvements are built in accordance with the plans. 4 Agenda Item No. 16B8 May 12, 2009 Page 10 of25 Task 4 - Monitoring: Water quality monitoring will be provided in order to demonstrate the project benefits. A detailed water quality monitoring plan will be submitted for review within three months of the grant award. Task 5 - Project Administration: Collier County will be responsible for contractor selection. Collier County and Rookery Bay National Estuarine Research Reserve will be responsible for contract development and administration and construction inspection. Collier County staff will be responsible for financial accounting and grant reporting to the Florida Department of Environmental Protection. 5 Agenda Item No. 16B8 May 12, 2009 Page 11 of25 PROJECT MilESTONES: Task Activitv Start ComDlete 1 Grant Application I Proiect Setup Month 1 2 Survev and Proiect Data Collection Month 2 Month 4 3 Civil Enoineerino Desiqn Month 2 Month 4 4 Construction Plans / Documents Month 3 Month 5 5 Permittina Month 6 Month16 6 Grant Award Month 16 Month 16 7 Construction Month 17 Month 25 PROJECT BUDGET: Project Funding Activity 319 (h) Amount Matching Match Source' Contribution Staff $46,895 Collier Countv. Travel Eauipment Supplies Contractual $60,420 $39,580 Collier Countv' BMP Implementation $661,317 $338,683 Collier Countv. Monitorina $36,000 Collier Countv. Public Education $20,000 Collier Countv. Other: Total: $721,737 $481,158 Total Project Cost: $1,202,895 Percentage Match: 40 'If a stormwater utility or other dedicated recurring fee is contributing, put that information in the following table. MATCH SOURCE INFORMATION: Match Source Name Description ERUlFee Collier County. Dedicated millage from Ad Valorem taxes for .15 mils stormwater manaaement 6 Agenda Item No. 1688 May 12, 2009 Page 12 of 25 BUDGET BY TASK: Project Funding Activity 319 (h) Amount Matching Match Source Contribution Task 1 - Construction Plans $60,420 $39,580 Collier County and Permittinq Task 2 - Public Involvement $20,000 Collier County Task 3 - Construction $661,317 $338,683 Collier County Task 4 - Monitoring $36,000 Collier County Task 5 Project $46,895 Collier County Administration Total: $721,737 $481,158 Total Project Cost: $1,202,895 Percentage Match: 40 OTHER FUNDING (Not Match - such as land acquisition or other federal grants): Aaencv Activitv Amount Collier County Desiqn and Permitting Consultant Fees $197,620 Collier County Surveying Consulting Fees $150,500 Total: $348,120 OTHER INFORMATION: If this is a multi-year project, have you requested sufficient funds to complete the project (assuming funds requested herein are provided)? (State yes or no, and, if no, provide an explanation): Yes: L8J No: 0 The Lead Organization, as listed on the first page of this form, agrees to comply with all requirements specified in the guidance package and in the federal grant regulations. Checking "no" or "yes, except" will cause the project to have a lower ranking than similar projects by lead organizations that agree to the requirements: Yes: L8J No: 0 Yes, except: 0 (Note: List exceptions below.) Exceptions: REFERENCES CITED: NOTE: PLEASE SUBMIT ALL APPENDICES IN A SEPARATE WORD DOCUMENT. THIS MAY INCLUDE MAPS, FIGURES OR ANY OTHER INFORMATION YOU WOULD LIKE TO INCLUDE WITH YOUR APPLICATION 7 Agenda Item No. 16B8 May 12, 2009 Page 13 of 25 DurA' Griffin Road Filter Marsh Section 319 Grant Location Map 0, N ,"'-"'," ..L'-' 1..l..... .' , ""~"'" Ma!)rnxd D'XZA'NC. Plannillg Visualizalion L~ C) N S U L TIN Ci Civil Engini..-"{'ring ....... ...... T 4 ...... Surveying & Mapping Agenda Item No. 16B8 May 12, 2009 Page 14 of 25 SECTION 319 COST ESTIMATE GRIFFIN ROAD FILTER MARSH 03-12-2009 by JJS DescriDtion Genera I/Startup/Entrance Excavation Plantings/Wetland marsh Final seed/Mulch/Stabilization Clearing/Grubbing Silt fence/Erosion control Concrete mat weir Access Road Contingency 10% Saie of Excavated Material (Credit) OTY U/M Unit Price 1 LS $25,000.00 371,066 CY $2.20 18 AC $5,000,00 24,000 SY $2,00 40 AC $2,000.00 7,000 LF $1.50 60 LF $700.00 140,000 SF $1.00 371,066 CY $150 Cost $25,000 $816,345 $90,000 $48,000 $80,000 $10,500 $42,000 $140,000 $1,251,845 $125,185 ($S:,6,599) $820,431 Assumes Cost based on drawing from county labeled "MCB-13 StormwaterTreatment Area Conceptual Master Plan" On-site stockpiling 20 ft width limerock access road around entire lake 50 ft of weir Entire marsh area 18 at replanted Excavation in 18 ac marsh to 3 feet deep Excavation in 22 ac lake to 6 foot min depth from control elev, (est. 8 feet of cut) seeding and mulch 30 ft width around project No blasting Does NOT Include Exotic removal Water quality monitoring Permitting fees and consultant fees Wildlife relocations Fencing IQ!s! Agenda Item No. 16B8 co Q') L{) i COON' <00_1 ~NO , 'CO ON~I Z~ <ll EfOOl 2:2&1 - I '" I "0 . c: <ll OJ <( ~ <:olE~ ~~",ir ~_..;! :::;:~il ","",11/' ~ i , ,f rS, l.t ;!l t ~,f ~ ~... ,,' ;i~. ~ c " (; '" ;;; c o '" " ~ Ul ,c on - " :0 " o ~ ~ a: <s .'2 ~ s ~ a " ~ E '" . o . Q; :: ~.~ ~ "'C~ S lVCO.";::tl3 ~~~:g ,,2 c: g>l.U LL ~~~~ L;tTI~~ ""J) ""' COON ",0_ -..r N 0 ..... S::'~ <D E ~Ol <D"'" ro ~":::D... ro "tJ C <D OJ <{ , ! <-~.., ~~..-~~ ",,:o'l 6i:1I I j .1 ~~ H :r~ ~~ , ;1 q> c " ~ " '" ;;; C o "" u " (/) .c <1> :;; ::;; "0 . " ~ . ~ S oS ii:.~ s -0 ~ -;S ~ ~ Q.~ c::<t:~~ .!: ~lJJ::5 :=:.="7t;'T;) ,;::.~ t.:: c: Cl UJ~.5 Agenda Item No. 16B8 May 12, 2009 Page 18 of 25 D'XZA'NC. Phmning Visualization C()N S U L Tl NG Civil Engineering ~ ~, , ~ .... Surveying & Mapping Project: Proj. #: Culculated By: Ch,,'Ckcd By : Grim" Road Outfall 080105,00.00 JAZ Date: 24-Apr-08 EJ R Dale: 24-Apr-08 Griffin Road Outfall Pre-Development vs. Post-Development Analysis Content - Assumptions - Pre - development Load Analysis - Post - development Load Analysis - Stonn Treatment - Recommendations - Land Use Summary - Lake Volume S' 2Wh "',,,1 ','. "Oil "(,]',lli" R,"',,; Ou:LoI: 1 ','I~ (""llT.,1 ('"",,,11.11,,,,,, _ hie "","m~ en.in' ('",,'''];11;1':1' 2""" "~_'~ iLL:',l'" i 1.1 1 I"" \\''1'.~, l);,,,tm .'.h ('('nl~m I ,'f\ 4 ~ . 21"'<; I:' ~ ~ I'\J Agenda Item No. 16B8 May 12, 2009 Page 19 of 25 D\X~^INC. Planning -. - Visualization CC)N S U L TI NG Civil Engineering .A. "-, , .L .... Surveying & Mapping Project: Pn~. #: Cakulatcd By : Checked By : JAZ E.JR Griffin Road Outfall 080105.00,00 Di;ltC: 24-Apr-08 Date: 24-Apr-08 Griffin Road Outfall Pre-Development vs. Post-Development Analysis Assumotiolls 1. The total Project Arca will consist of 44,7 aeres. 2. The total Drainage Area will consist of 364.9 acres for which the water management system will be 3. Calculations based on the June 2007 Evaluation of Current Stormwater Design Criteria within the State of S:,~OO~\\)f((lIIJ5.(lII.i'i) Grim" ROdd (Jutialln(j()~ Gcn~r,,1 (\n:wl1,lti,'n Er]giJll'elil1~\Gr.Hl1 Cdculalj('n,,-20[l~.\i.+':'411~I\<:Y H~rl'e, \\,I1Cll)uJlil:.~h i\"l.lmplin11> ~"r8 4]-'::::<I(j9 12:.,31'\1 Agenda Item No. 16B8 May 12, 2009 Page 20 of 25 D'lZA'NC. Pl~\lllling Vi"llali"ni(l!l ('ONStj(~'I'I"Cj Civil EnJ::Hlt'cnng .A. ~, '.A.. ..... Surveying & Mapping I'n1in:1 rwj C~It'lda(cd !i~ Chcekl.:dlly: Criffi" HnadOutfall Ol'lllIUS.llll.lJlI ,I.-\L LIR Dale' l..f--\pr.UH Dalt': 24-..\pr-llH Griffin Road Outfall Pre-Development vs. Post-Development Analysis Pn'-dcvclulllOcnt Characteristics Land Us(' Summarv Land l'se Catcgon Area Conditions U~l"l:S Si11glL'~F<llllily 1~('sldt::ntial L()\~ -DI.:.'llsilY Rl:siJlCntial Opcn/Undc\'chlj1l..'d Highway ]06.9 176.5 69.4 12.1 N'A ~'A (J(lod N.A .~64.9 Ground Cover:' Soil T\'llc Ground COn' I" HSG Singlc-Family Rrsidcntial Low-()t'usit) Rl'sidcntial Opcn/lilldc\c1oprd Highway D D C-D II Cune r\umbcr I Runoff Coefficielit Land Lsc Catcgon nOli ~ DClA C~ C \'alue From Appendix C: Z'Hll' 4 Fn'lll TR* 5~, Tdhle 2-1 Single-Family ResiJential (Jon", lmrcr\'inus C(in~r) {HSG Dl Ltl\\'-Dcnsity Resiuential (300'0 Imrt:niou<;, '\rca) dlSG [)) OpcnlJndevclop..::-u (\\'oods) (Fair C(1nJitlOn) (HSG C-D) Highway (40% Impervious Covcr) lHSG D) Q2 86 76 93 0.676 0.386 0.103 0.646 '" TR= Technical Rdl'(IsC S""'''~'<''''I""",,,,,,, ""f,-,,, ~,,",I' ,,"i,,11 ,'" ^ (x,,,,,,1 C""',III,.,,;,,!, hlP""'""t' (,r;,," [-ok ,i'lJn<>.}d"-',,,;_!. 11"",-, 11;,,1'<' \' "".,. 1)".1", ,I, I"l",tn-dpl(,.,; -,""h-,Ie '"I' 4 :~ :"LI" 1:'1'1'\_j Agenda Item No. 16B8 May 12, 2009 Page 21 of 25 D\XT:A1NC. Phlllnillg ViSlmli7.alion CON S U L TIN (i Civil ElIgil1<:xring ...&.. ....., , .4. ..JL Sur\'cvinc & !\bnoinl! Annual Runoff Volumes ProjeCI: Proj. i!: C<ikululeu By; C\1cl"kcd By: (;rifti(] RoaclOutfall IINlIIU5.00.0U JAZ E.IR Date: 24-.\pr-UlI Date: 2-l.Apr-UH Annual RUllolr Vol. Annual Raini~ill (iniyr) >I: Area (llC) '" C Value >I: (I fVl2in) Land list' CatcQor\' Annual Rainfall Depth (ilH.:hcsiy(,:an Fmm Appendix A.3 Area (' Value Runoff acrc-1t."yr a,:n:s Single-Family Rl:sid(:ntial Low-Density Residential Opcn!Undcvch)pcd Highv.'ay .53.00 53,('0 53.00 53.00 ]06.9 176.5 69.4 12.1 0.676 O.3X6 0.103 0.646 3]9.2 300.9 31.6 34.5 Runoff Characteristics mg'l Total Phosphorus (TP) mg/] Land Use Category Total Nitrogen (TN) Single-Family RL'sidcntial Low-Density Rcsidcnti.JI Open/Undeveloped Highway 1.43 1.6] 1.15 1.64 0.361 0.191 0.055 0.210 From Tablc4-S.a From Table 4-17 From Tahlc4-17 FW111 Table 4-1 S Prl'-devclonml'llf Loadill1!S of TN & TP TN load (kg/yr):= RUlloff(ac-ft'yr) '" 43.560 It''2/ac '" 7.4R g:aJife'3 * 3.785 Iltcc'gal '" TN (mgi'!) '" 1(J^~6 (kgilng) TP IO<ld (kgiyr) = Runoff (ac-ft/yr) '" 43.560 ti' liac * 7.48 gal;ff"^j '" 3.::\5 liter/gal >I< TP (mgiJ) >I: 10'-6 (kg/mg) Land t;s(' Catcgorv HUlloff Total Load Acre-tiyr kg:yr TN TP 319.2 5(l2.9 ]42.] 300.9 597.5 70.9 31.6 4U 2.1 34.5 69.X 9.4 686.2 1.274.9 224.5 Single-Family Rcsid('lltiaJ L(l\~-Dt.llsity Residelltial Open/Undeveloped Highway Total ~:'2""~'1I~"1"<."'!.f1" G"ffi" ](~.<I"h"t~11 ,""" (;"",,",.1 C"",ul"""n L,,~m'ct1ni'I.'.n' (' "\,,,1."',"0,.2<><>'1'''4 '~ I'"t,.~. II>,p" \\,,"'. V,,"iit. .,1. l"f~-MH'lr LNd "MI,~" 4 nj~ ~-:,;...;,,,,,~ I~,::' PM Agenda Item No. 16B8 May 12, 2009 Page 22 of 25 D\XZA'''C. Planning Visllalizatinn C () N S l L T I !'J (, Civil EngineeJin<,' ...... " , .L ..... Surveying &: M:1J1ping Pwjn:t. Prnj. # Cakulllied By Cf1l'd.:ed By Griffin RO:l.dOulfl\lI n81110:'.OIl.OO .HZ Dale: 24-A"r_08 EJR Dall'; 24."\pr.08 Griffin Road Outfall Pre-Development vs. Post-Development Analysis Post-den-Iooment Characteristics Land FSl' Summar\' Land Use Category Art'a Conditions acres Single-Family Residential Low-Density Residential Open/l1ndevclopcd Highway La~t.'Ti]fcr j\.ldfsh IOA.9 176.5 24.7 12.1 44.7 364.9 !'-:/A !'-:/A Good NIA N.'A Ground Con:r! Soil T\'De Ground Cover HSG Single-Family R('sidenti~ D Low-DelIsit" Residential D Open/l1nde\'(>loped C-D Highway D Lake/Filter Marsh 1\'/.1\. Curve :\umber I RUlloffCoefficient Lund llS{> Cat<.'gory lion - DCIA eN C Ynlne From Appcndix Frolll TR* 55. Table 2-2 C: Zonc 4 Single-LlInily Rt'sidenti~1 (7()t~,;, I!l1pcn'i(lu~ Co\'er) (HSG D) Low~Dt:l1sity Residential c;O'~'" ]mpenious Ar~al (HSG D) Opel1,l'nde\elopcd {\\'ood..;} (Fair Condition) (HSG C-D) Highway La~e{r-ilter \1arsh n 86 76 93 ."1.,\ 0.676 0.386 0.103 0.646 :\if.:\. * TR= Technical Release s. ,(,,:,~ (J~" I'" no.('Ll (;,;'1'0 I(".,\j ll,,'I,il C"I'" "(-"er~I' ",..(,Iu,;"" h"""-,, "", (;,""" '"kLJI,,,;,,", "Ii,q.rq__'~ II" '" 11...",,; \\ ""' (.\u.,lil~'..d. I'o',",ic"'dJ' L,,~d ,,'OJ,,':,j, < "I ,. .1 :~ .'i)'l" 1.'.'.'1'\1 Agenda Item No. 16B8 May 12, 2009 Page 23 of 25 D\XZA'NC Planning Visuali7,ali\m CON SlJ L TI N G Civil Engineering ...... ....., , .L ..... Survcvinl! & \1;ltmil1l! Project: Proj. #. Calculated By : Checked By : Grim.. Road Oull'llll 080105.00.00 .IAZ EJR Date: 24~Apr-08 Date: 24-Apr-08 Annual RUlloff Vlllumes Annual RUllo1TVoJ. = Annual Rainfall (in/YT) '" Area (ae) '" C Value'" (lft/12in) Single-Family Residential Low-Density Residential Open/Undeveloped Highway Lake/Filter Marsh noo 53.00 53.00 53.00 53.00 101>.9 171>.5 24.7 12.1 44.7 C Value Runoff acre-ft/yr 0.671> 319.2 0.3RI> 300.9 0.103 11.2 0.041> 34.5 NiA 0.0 Land Use Categor\' Annual Rainfall Depth (inches/year) From Appendix A.3 Area acres Runoff Characteristics l...and IJse Categor~. Total l\'itrogen (TN) mg./l Total Phosphorus (TP) mg.!] Single-Family Residential Low-Density Residential Openll.:ndeveloped Highway Lake/Filter Marsh 1.43 1.61 1.15 1.(,4 I'i/A 0.361 0.191 0.055 0.220 N/A From Table 4-5.a From Table 4-17 From Table 4-17 From Table 4-18 Pre-develooment Loadlnus ofTI\' & TP TN load (kg/yr) ~ Runoff(ac-fi/yr)' 43,560 ft^2/ao * 7.4R gal'W3 * 3.7R5 jj'er!gai * TN (mg/i) * 10'-1> (kg/mg) TP load (kg:'yr) = Runoff(ac-ft!yr) '" 43,560ftI'2/ac *' 7AR galiW'3 * 3.7X5litcr/gal * TP (mg/l) * lQl'-6 (kgfmg) Single-Family Residential Low-Density Residential Open/lTndc\'cloped l.fighway Lake/Filli:r Marsh Total l{ulloff Total Load Acrl':+ft/yr kg.!yr T1\; TP .1] 9.2 562.R7 142.10 300.9 597.46 70.XR 11.2 t5.94 0.76 34.5 h9.R3 9.37 0.0 0.00 0.00 665.8 1_246.09 223.10 Land lJse Category S,.~;IC', \lS(ljG.\.($l_uiJ(~,iff," R,,,'" O"lbll OIiM r;~"",.~1 ('o"",h;",,,,,. I-_n!;i"cn;!l~(,,'a"t (alwloliom 'OO".(),l':'-! II~rq':'I'h'l'~r \\.'"\~f ':)""III,'"ls 1'''''hk\~lrt.nad ,\nal,".;s f,.-.r, '7100') 1:::".1 I'M Agenda /tern No. 16B8 May 12. 2009 Page 24 of 25 D'X T.AJNC Pbrminc \'i~IJaljL~;lli('11 ("[)J'...:S t 1 L~I'INC Cj\.jj EIl.l'lIw....rirll,! ..... '-, '.L. ...... Sun.c) iUt: & M'-ll'ping f'rujl'~! : l'r".i.!i; Cakulmcd By Chcd(dlly .HZ UR (;riffill kuadOurfall mWIU::.f1U./JO DiM 14.'\fJr-UR Date 14-"\llr-rtK Griffin Road Outfall Pre-Development vs. Post-Development Analysis Storm Trcatllll'nt Charal'lcrislic~ 0[\\'('1 Detention Treatment Lakes Lake Surfare Area ~l('an [)cprh VoluflIe t\1ll'l;illlulQ Depth Acres f1 ,K'l"c'-fl f1 LakeTiltcr Marsh 4..1.7 75 3J~,J I ~.t1 Trcatm('1I1 Pro\"i<kd h\" Lllkl's L.uke DCIL'llliOIl Tink I{by) = \'$!UIllO: (llt:rL'.ft) Annual RUlJnff iaac-flyr) "J(15 till) yr T'\ Removal '" 4375 i, Lake Dclc11li\m fllTle {4,__U~+ Like Delcnti(lll Time) From Figure )-10 Tr Rl'1l10\al = -tll.13 ~ 6.__n~ In I L.Jk(' !kk11lill11 r 11llL'1 (J.=' 13 ~'( In (Llk Dt'kntioll Time) 1: From Figurt' )-9. Basin: Lake/Filler Marsh Lake DClemipn - J 1-:4 days J'ar:lllwlrr Inpuls RCIlI(J\lll Disrh:lrgc " " Tl\' 1.~46.J kg yr ~~.7 713,(1 kg)r TP 2n.l kg yr 7t)1 -1(-1.54 kg yr RUJlnflVnlul1l<: ()(l),Xaere-hyr fl()).Si.t>.:rc-l'tyr COllmare Pre- and Posl- dc\"cJoDJlJent Lo,uJill!! Pllrallll'll'f Pre-de\cloplIll'lIt POSI-dl"rluplllcnl TN TP J.::74,() kgyr 224.5 kgyr 71.1.6 k~ yr 46,_'1 kg yr ['aluale Dt'pIII of Pond .\110:\111 "lean TP cone. ill di.sehargc Imgl) Annual TP Ji", (kg yr) ',l yrlOutJlrm Vll].~ L;tk,,' \'(\1.) (ac-f! )" a(; 43S6() W2 * ft 3741\ gal *' gaLJ_7li'5L" 10'6 rng'kg Mean ChyJ-aconc (Jllgm J) = In Ichyl-a) '" L05S '" In ITP} _ 0,9."\4 l' I J.05X "In (TPl - 0,934) E4 41p 6-46) Ml:llJ) S'xchi Di4: SD derl!l (111) "" (~'.42JS(1'r ll_\041 * dly'l-a) ((d)6}2 _ ehyl-:t) Fwm Figure 6-14 Depth o!" DO (111) Oc .1.035 Sc'cclli . {j {)2 164 \ ehyl-;l- 11_1)1)4'J":'4 l; TP [4.5 (p_ h-4S1 v,s ".''1,1 "'';''.1< "'.'.".1:""'"';''''' I"" I i."~,,, " ,'h" l ,'d,' '''1'\1 Agenda Item No. 16B8 May 12, 2009 Page 25 of 25 D\l "A'NC Planning VI:.u;:lizallon CnNS'-:I..TT~'C; Cil,jlle.1l!!]]I",'!ill!,': . '- l' Y I. .. 0;;",,.,,.,,;,,,, ~ ~t."~;",, ['r''I,'ct: Proj..I: ('akul0l1~(llly . Chcd,l'dlh: .IAZ LIR Crim" HoadOulf:11I mWI[)S.lln.lIO Dm~: 24-.\llr-1I11 !>ale: 24~Allr-Oll Lak~'Filtt,'r Marsh AIIIIlIalTP '\lIlIual \'olumc Mean TP 1\1can Ch~l- a Mean Scn'hi Dl'plh of Disdtarge Dis{'haq;:c COllcclItratio Conccnlrtltioll Disk Depth Anoxia I\lcan Depth of Lake II kg yr ac-f1-yr pg'l lTIglll'3 m m ft Ii 411:"4 h(1)S3 37.64 lK..2S 1.22 39 11.9 7.5 Lake Rc-commcudalions ~. :',,,. ,,' j.b' ,'''', (."1,',,, 1(",,;, ',,1l,tJ """ (;,.",~"" ,.,,,,;11;"; . I.,';,''','n,,',,- (.,,,,, ' ".,..1"" . ,',. ,;"':" II..r.... II, 1'<" W'H!"~,,,"I'" ~'''m..'I!"'' "". ~: :Ole" 1:1'1'\1