Stormwater is defined as water that originates during precipitation events (i.e. rain or snow), and/or water that originates with snowmelt, which enters the storm water system (catch basins, piping, etc.).
Discharge to Surface Waters
Storm water that does not soak into the ground becomes surface runoff, which either flows directly into surface waterways or is channeled into storm sewers, which eventually discharge to surface waters.
Storm water is of concern for two main issues: one related to the volume and timing of runoff water (flooding) and the other related to potential contaminants that the water is carrying, i.e. water pollution.
Clean Water Act
Under the Environmental Protection Agency (EPA) Clean Water Act, the National Pollutant Discharge Elimination System (NPDES) Stormwater Program regulates stormwater discharges from three potential sources.
The Town of Westbrook operates under a Municipal Separate Storm Sewer System (MS4) permit, which is designed to prevent stormwater runoff from washing harmful pollutants into local surface waters such as:
- Coastal Waters
The Town is required to conduct and track activities in accordance with this permit and demonstrate Best Management Practices (BMPs) in six different categories. An annual report is submitted to DEEP to show compliance.
Westbrook Stormwater Management Plan
The goal of the Stormwater Management Plan adopted by the Town of Westbrook is to reduce pollutants from reaching the waters of the State. Some examples of residential pollutants include:
- Automobile care chemicals
- Pet waste
- Septic systems
Another component of the NPDES is the Stormwater Pollution Prevention Plan (SWPPP) on file with DEEP for both the Town Garage and Transfer Station facilities.
These SWPPPs are required in accordance with the Connecticut General Permit for the Discharge of Stormwater Associated with Industrial Activity, due to the nature of the activities conducted at each of these sites.
Monitoring & Tracking
As with the MS4, the Town is required to monitor and track activities, and conduct outfall sampling. All of this information must be submitted in an annual report, for each facility, to DEEP.