Anticipated Stormwater Engineering Services RFR
Stormwater treatment at River Road in Westport, MA
Last update: January 15, 2013
In partnership with the Town of Westport, and the Westport River Watershed Alliance, and as part of our municipal grant program, in September 2011, the Buzzards Bay NEP committed $20,000 to the Town of Westport for design services in anticipation of providing engineering services to assist the town develop stormwater treatment designs to reduce stormwater volumes and pollutants discharging from three sites on River Road to the West Branch of the Westport River. The BBNEP will oversee and administer the engineering contract on behalf of the town. We are posting this information to increase awareness of this initiative, and in support of the anticipated posting of a Request for Responses (RFR) on the CommBuys website.
After field investigations of stormwater flows and field sampling, it was ascertained that road runoff may not be the principal source of pollution along this portion of the river, and that treating stormwater along this portion of the road would have appreciable costs with modest benefits. Based on these findings, the Town of Westport withdrew from pursuing stormwater treatment designs. No RFR was posted for these services.
The Town of Westport is seeking to treat stormwater discharges from River Road to the West Branch of the Westport River. The upper West Branch is currently permanently closed to shellfishing due to numerous sources of pathogens. Because of the number of sources of pathogens to the river, the Town of Westport and the Buzzards Bay NEP recognize that water quality improvements will be achieved only through the systematic treatment or elimination of many sources that discharge bacteria to the river. Such an undertaking will remediate the largest sources over many years. The town, property owners, and non-governmental organizations, like the Westport River Watershed Alliance, have been working toward these long term solutions.
The focus of this remediation effort is to reduce stormwater volumes and bacteria discharges associated with three pipes shown on the maps shown here. The Buzzards Bay NEP expects to make available $20,000 in federal funds to hire an engineering or environmental service firm. The selected firm will produce stormwater designs for the Town of Westport that reduce stormwater discharge volume and pollutant from these sites. The funding of these designs fulfills a previous award commitment to the Town of Westport under the Buzzards Bay NEP Municipal Grant Program.
Designs may include infiltration biofilters, or various other LID techniques. The Buzzards Bay NEP staff will work with the selected vendor, Westport Board of Selectmen, and the Westport Highway Department to decide upon the most practical and cost effective stormwater management solution given the constraints of the sites. After final designs are complete, the BBNEP will work with the Town of Westport to obtain funding for the construction of the stormwater designs.
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The Town of Westport requests consideration from the Buzzards Bay National Estuary Program for services (assessment and feasibility) for stormwater remediation/ bioretention design. The she of this project is on along River Road in Westport, Massachusetts (See Figure 1 -Location Map). The area of consideration is drainage from three municipal separate stormwater systems moving runoff from River Road into the West Branch of the Westport River. The area of water resources impacted by the stormwater drainage is on the 303 (d) list for impaired waters for nutrient and pathogen contamination.
The specific pollutant associated with the stormwater discharge is fecal coliform bacteria causing shellfish bed closures in the area. (See Figure 2 -Shellfish Closure Status). Figure 3 shows a locus map of known drainage networks discharging into the West Branch of the Westport River. Data collected by the Westport River Watershed Alliance (WRWA) for two storm events is included in attachment A. Fecal coliform levels in stormwater runoff exceed shellfishing and primary contact recreation standards for the two storm events sampled by WRWA. Sample site locations for stormwater runoff testing are described in Figure 4. The WRWA is willing to collect stormwater runoff samples for the Town to further assess bacterial loads.
The Town of Westport owns the road up to 40 feet in width. Figure 5 shows assessors map of the area. The Town would consider BMPs that may require the road to be dug-up and/or may result in a reduction of road width. The town also has the ability to dig test pits, to allow the Buzzards Bay NEP to evaluate soils and the water table at the site. The Town can also provide copies of town plans, engineering as-builts, and any other existing pertinent information needed to assess the project. The Town Administrator or their appointed project coordinator will participate in necessary site visits and meetings to develop a conceptual stormwater remediation plan for the site.
There are electricity service poles on the eastern border of River Road (on the river/marsh) side. The Town Highway Department is contacting DIGSAFE to see if any other utilities are in the road layout. The Town of Westport also agrees to have representatives from the Conservation Commission and the Highway Department meet with the Buzzards Bay NEP and/or private engineers, as necessary, to finalize designs for the stormwater remediation project. If final stormwater designs or engineering plans are developed, the Town of Westport would require assistance from the Buzzards Bay NEP to develop a grant application to fund the implementation of those final designs.”
Expected environmental benefits of proposed work
The Town of Westport has made great efforts to reduce municipal stormwater pollution. The Town has partnered with the Buzzards Bay National Estuaries Program as well as other nonprofit groups to remediate stormwater discharges, to help farmers implement agricultural best management practices (BMPs), and teach homeowners the importance of maintaining adequate and maintained septic systems. The expected environmental benefit of the proposed work is to minimize, detain, and retain stormwater runoff and reduce fecal coliform pollution. The goal of the proposed project is to eventually improve water quality to open previously closed shellfish habitats for the economic and recreational benefit of the community.