City of Nashua, NH
MS4 Assistance 2021-2022
Scope of Work for Engineering Services
6. BMP Potential Retrofit Inventory
The Permit requires an inventory and priority ranking of permittee-owned property (including parking lots,
buildings, and maintenance yards) and existing infrastructure (right-of-ways, outfalls and stormwater
conveyances, swales, and detention practices) that could be retrofitted with BMPs designed to reduce the
frequency, volume and pollutant loads of stormwater discharges to its MS4 through the mitigation of
impervious area.
The inventory and priority ranking must consider factors such as access for maintenance, subsurface geology
and infrastructure, depth to water table, slope and elevation; and proximity to and public safety when
evaluating potential retrofits. Hazen’s duties include:
Task 6.a Site visits and preparation
Task 6.b Document findings of site visits and compile inventory.
Task 6.c Conduct workshop with City of Nashua to rank potential BMP retrofits.
Task 6.d Prepare a report detailing the findings and recommendations along with a schedule for
implementation based on the rankings.
Deliverables:
e Ranked Inventory of Potential BMP Retrofits
e BMP Retrofit Report
7. Annual Reports
The Permit requires submit of annual reports that include:
e review of permit compliance
e assessment of selected BMPs.
e status of the any plans for discharges subject to TMDLs or to certain impaired waters
e progress towards achieving the measurable goals and objectives of the six minimum measures
Hazen’s duties include assisting the City of Nashua in completing the year 3 and year 4 annual reports using the
templates provided by the New Hampshire Stormwater Coalition.
Deliverables:
e Year 3 Annual Report due June 30, 2021
e Year 4 Annual Report due June 30, 2022
JANUARY 2021
