3. Direct the Engineer to prepare a feasibility study that complies with the requirements of the USACE and BCWMC criteria.

Transcription

1 Memrandum T: Bassett Creek Watershed Management Cmmissin Subject: Item 5C Cnsider Apprval f Prpsal t Prepare Feasibility Study fr the Jevne Park Strmwater 5C. Cnsider Apprval f Prpsal t Prepare Feasibility Study fr the Jevne Park Strmwater Imprvement Prject (2020 CIP Prject ML-21) Recmmendatins: 1. Cnsider apprving the scpe f wrk and $70,200 budget presented in this memrandum and direct the Engineer t cmplete the feasibility study fr the Jevne Park Strmwater Imprvement Prject (2020 CIP Prject ML-21), scheduled fr cnstructin in 2020 and Direct the Engineer t cnsult with the U.S. Army Crps f Engineers (USACE) t determine whether the Resurces Management Plan Pre-applicatin Cnsultatin Prtcls may apply fr this prject. 3. Direct the Engineer t prepare a feasibility study that cmplies with the requirements f the USACE and BCWMC criteria. Backgrund As the City f Medicine Lake is nearly all surrunded by Medicine Lake, maintaining and imprving the quality f the lake itself is paramunt. Given the city s size and current infrastructure, there are limited pprtunities fr strmwater management retrfits, with the exceptin f the Jevne Park area. The prject gal is t cnstruct an imprved water retentin pnd in Jevne Park, which will result in: better management f strmwater runff as the city has n municipal strm sewer system increased capacity fr strmwater strage within the pre-existing natural pnd/wetland and swale in Jevne Park a better way t rute, carry and stre excess strmwater t minimize flding within Jevne Park and n adjacent residential prperties (apprximately 15) reduced sediment and phsphrus lading t Medicine Lake reduced City f Medicine Lake capital and maintenance expenditures assciated with rad and culvert repair caused by excessive vlumes and rates f runff sustainability f existing waterfwl and wildlife habitats Barr Engineering C MarketPinte Drive, Suite 200, Minneaplis, MN

2 Page: 2 This prject is intended t imprve cnditins fr smaller, mre frequent strm events but is nt intended t address the backflw frm Medicine Lake nt the peninsula when water levels are abnrmally high. Events greater than the 10-year (10% chance) event can result in high water levels n the lake that backflw int this area. Jevne Park is within the 100-year (1% chance) fldplain fr Medicine Lake, as fficially mapped by FEMA. The Jevne Park area is nt a Minnesta Department f Natural Resurces (MnDNR) public water r wetland. Hwever, this area is mapped as wetland as part f the Natinal Wetlands Inventry (NWI) and is als flagged as a ptential wetland in the Hennepin Cunty Wetlands Inventry. Medicine Lake is listed as impaired n the Minnesta Pllutin Cntrl Agency (MPCA) 303d list fr mercury, chlrides, and excess nutrients (e.g. ttal phsphrus) and a Ttal Maximum Daily Lad Study (TMDL) fr the excess nutrients was apprved in The TMDL identified a needed reductin in watershed lads t Medicine Lake by 28 percent; hwever, the wastelad allcatin assigned in the TMDL was categrical, meaning the City f Medicine Lake was nt assigned a lad reductin specific t the city. Figure 1 shws the lcatin f Jevne Park. As is required fr BCWMC Capital Imprvement Prject (CIP) Prjects, a feasibility study must be cmpleted prir t BCWMC hlding a hearing and rdering the prject. The feasibility study will develp cnceptual designs f the drainage and water quality imprvement prject, review the permitting requirements, and develp cst estimates fr each cncept f the prject. This prject is cnsistent with the gals (Sectin 4.1) and plicies (Sectins 4.2.1, 4.2.2, and ) in the BCWMC Watershed Management Plan. The BCWMC cmpleted a Resurce Management Plan (RMP) in 2009 thrugh which the USACE and the BCWMC agreed n a series f steps, wrk items, deliverables (called prtcls ) that must be accmplished and submitted t cmplete the RMP prcess and USACE review/apprval prcess. Althugh this prject was nt included in the RMP, the USACE has allwed the RMP prtcls t be applied t ther prjects nt specifically included in the RMP. With the cmpletin f the prtcls, we expect the USACE applicatin prcess t mve mre quickly than it wuld therwise. Mst f the prtcls must be addressed as part f the feasibility study, in additin t the usual tasks that wuld be perfrmed as part f a BCWMC feasibility study. In general, the prtcls require cmpliance with Sectin 106 f the Natinal Histric Preservatin Act, cmpliance with Sectin 404 f the Clean Water Act, and Clean Water Act Sectin 401 Water Quality Certificatin. Cmpliance with Sectin 106 typically requires a cultural resurces inventry. Cntent and Scpe f Feasibility Study The feasibility study will address and include the feasibility study criteria adpted by the BCWMC in Octber 2013:

3 Page: 3 Analysis f multiple alternatives with the cntext f Cmmissin bjectives, including the fllwing fr each alternative: Prs and cns analysis Cst estimate fr cnstructin and a 30-year cst Analysis f life expectancy Summarize each alternative fr the Cmmissin t judge its merits Cst estimate fr annualized cst per pund f pllutant remval Evaluatin f new and/r innvative appraches Identificatin f permitting requirements The BCWMC develped the abve criteria when the BCWMC s CIP was limited t water quality imprvement prjects, s they d nt specifically address fld mitigatin aspects f CIP prjects. As nted earlier, mst f the RMP prtcls must be addressed as part f the feasibility study. In additin t the tasks abve, the feasibility study will include the identificatin f wetland impacts t meet the RMP pre-applicatin prtcls. In additin t the RMP prtcls and specific criteria adpted by the BCMWC, it is imprtant t gather stakehlder input. The BCWMC Engineer will wrk with the BCWMC Administratr, and City f Medicine Lake representatives t identify the mst-effective means t gather input frm the public and ther affected stakehlders. Figure 1 shws the prject area cvered by this feasibility study. Belw is a summary f the wrk scpe cmpnents fr this feasibility study: 1) Prject Meetings a) Prject kick-ff meeting with BCWMC staff, and Medicine Lake representatives and preparatin f meeting ntes. b) Meeting with BCWMC staff, Medicine Lake representatives, USACE, MnDNR, and MPCA t discuss cncept alternatives and review permit requirements fr prject, and prepare meeting minutes t cnfirm regulatry agencies discussin results. c) Up t tw additinal meeting with Medicine Lake representatives, as needed. d) Biweekly updates t the prject team prviding updates n wrk cmpleted, upcming wrk, and any utstanding data requests thrughut the prject 2) Field Investigatins a) Envirnmental Investigatins: Review f the Minnesta Pllutin Cntrl Agency s (MPCA) What s in my Neighbrhd? database indicated the presence f a fuel tank n an adjacent residential prperty and the site is still currently active with the MPCA. Hwever, because the

4 Page: 4 histric land use f this area was primarily residential, we d nt anticipate widespread cntaminatin resulting frm this site that wuld impact the prpsed prject at Jevne Park. As part f this feasibility prject, we will request and review the infrmatin in the MPCA s file fr this site. We assume that after review f the MPCA file, a Phase I envirnmental site assessment will nt need t be cmpleted fr this prject and the prject shuld prceed with a cntingency plan in place if cntaminatin were t be encuntered during cnstructin. b) Wetland delineatins Barr will perfrm a wetland delineatin within Jevne Park, the wetlands suth f Peninsula Rad within the prject area, and the wetland lcated at the drainage frm Jevne Park. We will perfrm the field wetland delineatin in accrdance with the Rutine Level 2 prcedures specified in the USACE s 1987 Wetland Delineatin Manual ( 1987 Manual, USACE, 1987), the Reginal Supplement t the Crps f Engineers Wetland Delineatin Manual: Midwest Regin (USACE, 2010), and the 2013 Guidance fr Submittal f Wetland Delineatin Reprts t the USACE and WCA LGUs in MN. We will identify/flag and recrd wetland bundaries using a GPS unit with sub-meter accuracy. We will amend the existing wetland delineatin reprt that includes the wetland type classificatins and descriptins f the delineated wetlands, a brief descriptin f the prpsed prject, general envirnmental infrmatin, and a discussin f regulatins and the administering authrities. The reprt will als include wetland data frms, precipitatin analysis, and site phtgraphs. Barr als will btain a Wetland Type and Bundary Apprval frm the Lcal Gvernment Unit (LGU). Our cst estimate includes a wetland functins and values assessment (i.e., a Minnesta Rapid Assessment Methd, r MNRAM, analysis) f the wetland in Jevne Park. c) Tpgraphic and utility lcatin survey We will cmplete a tpgraphic and utility lcatin survey fr the prject area, including detailed survey f the utlet structure and verflw frm Jevne Park t Medicine Lake. As part f the tpgraphic survey, we will als take elevatin measurements f the tp and bttms f the banks t the wetland in Jevne Park and suth f Peninsula rad within the prject area, alng with the shallw wetland bttm. We will als perfrm tpgraphic survey f the wetland and lw area and channel dwnstream f Jevne Park. Althugh the City just recently cmpleted sme culvert wrk alng Peninsula Rad last year, we assume there is nt survey data available and we will als survey any existing driveway culverts alng Peninsula Rad that may cntribute flws t these areas. Undergrund utilities will be lcated based n the lcatin f manhle structures in the field, as-built/cnstructin plan drawings frm the City, and utilizatin f a Gpher State One Call utility lcate. We assume that HKGi will prvide the sanitary sewer data in electrnic frmat. We will cnduct the survey in NAVD88 and use available City f Medicine Lake r City f Plymuth benchmarks. d) Tree lcatin, diameter, species, and cnditin survey As part f the tpgraphic survey, we will als survey all trees with a diameter f 4 inches r greater, recrding the diameter, species, and cnditin (e.g. dead/live, shaggy/peeling/deeply furrwed bark) f the trees. In additin t

5 Page: 5 helping with estimated prject csts fr the varius scenaris (if tree remval is required), the tree survey will help determine if the trees within the prject area culd prvide habitat fr the nrthern lng eared bat (endangered). e) Sediment Sampling Because there is limited strm sewer infrastructure in the City f Medicine Lake and much f the runff that enters the wetland in Jevne Park passes ver turf and wetland buffer vegetatin befre reaching the wetland, it is unclear if significant sediment accumulatin has ccurred in the existing wetland. As part f the wetland delineatin task, Barr field staff will screen the sediments in the wetland in Jevne Park during the wetland delineatin t see if there appears t be layers f carse sediment accumulatin in the wetland bttm. If this screening indicates that there may be accumulated sediment in the Jevne Park wetland, we will cnduct sediment sampling f up t fur sediment cres t determine if the accumulated sediment is cntaminated, thus restricting the use f the dredged material, and t estimate the lcatin f the natural pnd bttm. f) Threatened and endangered species desktp review Barr will perfrm a desktp review f the available databases t determine the ptential fr adverse impacts t state and federally listed species. g) Cultural resurces desktp review - Barr will request review f the existing database frm the State Histric Preservatin Office (SHPO) fr infrmatin related t knwn histric and archaelgical resurces in the prject vicinity and will summarize any available infrmatin in the feasibility reprt. h) Prject easements The prpsed prject in Jevne Park is lcated n public prperty, s n additinal easement acquisitin is anticipated. Hwever, if the prpsed feasibility prject cncepts extend t the lw areas and channel suth f Peninsula Rad, the prject wuld be lcated n private prperty and easements wuld be required. This will be identified as part f the feasibility study. 3) Evaluatin and Cncept Plans a) Develpment f up t 3 cncepts fr develpment f a strmwater management pnd in Jevne Park, cnsidering input frm stakehlders. The develpment f these cncepts will cnsider tree remval estimates fr each cncept (if applicable), including remvals needed t gain access t implement each cncept. b) Use f the BCWMC Phase 2 XP-SWMM and P8 mdel t estimate impacts t peak fld elevatins and pllutant remvals, respectively, as a result f the prject cncepts. c) Identify permitting requirements fr the cncepts, based n wetland delineatins and ther cmpiled data, and ne (1) meeting with USACE, MnDNR and MPCA staff (see task 1b).

6 Page: 6 d) Develp cst estimates fr the prject, including a 30-year cst, analysis f life expectancy, and annualized cst per pund f pllutant remval fr the water quality treatment prtin f the prject. e) Evaluate the fld reductin benefits f the prject, including acre-feet f additinal fld strage prvided, impact (if any) n Medicine Lake fld elevatins and flding that ccurs during smaller strm events (e.g. 2-year and 10-year events), and impact n hmes in the fldplain (e.g., are any hmes remved frm the fldplain, is there a reductin in the inundatin depth at adjacent radways). 4) Public Engagement a) Crdinate with BCWMC Administratr and City representatives t determine the best means t gather public input, such as mailings, newspaper articles, pen huses, etc. Primary grup fr public discussins will be the nearby residents and prperty wners, including residents living arund and users f Jevne Park. The budget fr this task includes time t prepare fr and attend ne public meeting early in the prcess, prir t develpment f cncept plans. We assume that meeting crdinatin, expenses, and set-up will be largely cmpleted by the BCWMC Administratr in clse cllabratin with the City. This task includes assistance with public invlvement prcess as necessary preparing handuts, bards, and/r presentatin, and recrding and cmpiling cmments. 5) Feasibility Reprt a) Prepare draft reprt fr review by City representatives and BCWMC staff; revise reprt based upn review cmments. b) Present draft feasibility study findings at BCWMC meeting. c) Prepare final reprt fr apprval at BCWMC meeting and fr use at future prject public hearing. d) Present final feasibility study findings at BCWMC meeting. Cst Estimate Table 1 summarizes ur cst estimate fr the scpe f wrk utlined abve. Table 1. Jevne Park Strmwater Imprvement Prject Feasibility Study Csts Tasks Estimated Ttal 1) Prject Meetings $8,800 2) Field Investigatins $23,500 3) Evaluatin and Cncept Plans $20,200 4) Public Engagement $ 4,200 5) Feasibility Reprt $13,500 Ttal $70,200

7 Page: 7 Schedule We will cmplete the tasks and milestnes utlined in the scpe f wrk n the fllwing schedule (assuming authrizatin at the July 2018 BCWMC meeting). Tasks and milestnes Estimated Schedule Kick-ff meeting with BCWMC and City f Medicine Lake August 2018 Representatives Wetland delineatins July/August 2018 Cmbined agency field review/tep review August/September 2018 Envirnmental Review August 2018 Tpgraphic, utility, and tree survey August 2018 Desktp Review threatened and endangered species, cultural August 2018 resurces Sediment sampling September 2018 Meeting with BCWMC, City, USACE, MN DNR and MPCA September/Octber 2018 Develp cncept alternatives and cst estimates Octber January 2019 Public meeting February 2019 Submit draft feasibility reprt fr City and BCWMC staff review March 8, 2019 City and BCWMC staff cmplete review March 22, 2019 Submit draft feasibility reprt fr BCWMC review at Cmmissin April 10, 2019 meeting BCWMC cmpletes review at Cmmissin meeting April 18, 2019 Submit final feasibility reprt fr BCWMC review at Cmmissin May 8, 2019 meeting Final Feasibility Reprt BCWMC apprval at Cmmissin May 16, 2019 meeting

8 Medicine Lake Subwatersheds Legal Bundary Parcels PrjectArea 238 Cntur Type R Peninsu la Ft Cntur 234 d 2-Ft Cntur Park Jevne n Pe in 176 su 185 la Rd Barr Fter: ArcGIS 10.4, :28 File: I:\Client\BassettCreek\Wrk_Orders\2015\Phase2_XPSWMM_MdelUpdate\Maps\Reprts\Bassett_Reprt\Figure 2-1 Watershed.mxd User: rsm Medicine Lake Medicine Lake Feet Jevne Park Prject Area BCWMC ;! N Aerial Imager y: 2015 FSA FIGURE 1 200