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Understanding BWSC’s New Stormwater Charge

Effective April 1, 2024, the Boston Water and Sewer Commission (BWSC) will implement a new Stormwater Charge. The intention of this charge is to ease the impact of impervious surfaces on the City of Boston’s stormwater infrastructure by funding repairs to existing infrastructure, installation of new green infrastructure, and improvements to drainage systems. Ultimately, the Stormwater Charge aims to fund the City’s compliance with the Clean Water Act and a Consent Decree with the Conservation Law Foundation and the US Environmental Protection Agency (EPA).

How will the Stormwater Charge impact me?

All properties with more than 400 square feet of impervious area will be subject to the new Stormwater Charge. To calculate the Stormwater Charge, BWSC will use a unit called the Equivalent Residential Unit (ERU), which is intended to represent the impervious area on a typical residential property. One ERU is equal to 2,164 square feet and will equate to a charge of $8.98 per month.

Properties with more than 400 square feet of impervious area and one to six residential units will be charged for 1 ERU, or $8.98 per month. Institutional, commercial, industrial, and residential properties with more than six residential units will be charged based on the amount of impervious area on site. Impervious surface area will be determined by BWSC using GIS data and aerial imagery. For example, a property with 45,000 square feet of impervious area will be charged for 21 ERUs, or $188.58 per month.

How can I reduce my Stormwater Charge?

To offset costs to customers, the new Stormwater Charge will be accompanied by a reduction in sewer rates, and BWSC will give customers the opportunity to apply to various programs, including a Stormwater Credit Program.

The Stormwater Credit Program will provide up to a 40% credit towards a property’s Stormwater Charge for property owners that implement educational programming or Best Management Practices (BMPs) which meet specific BWSC standards. The Stormwater Credit Program will recognize existing BMPs installed more than five years ago, but these BMPS will require certification from a Massachusetts Registered Professional Engineer (PE). BMPs not previously installed under BWSC site plan will also be subject to additional requirements.

Customers can also participate in BWSC’s Stormwater Grant Program or perform Impervious Area Reduction to reduce their Stormwater Charge. The Stormwater Grant Program will provide a 50% reimbursement for the implementation of new stormwater management programming or BMPs, up to $4,000. Additionally, customers may apply for impervious area reduction by providing evidence of the impervious area removed. Once BWSC confirms the impervious area reduction, a new ERU and Stormwater Charge will be calculated.

How can Nitsch help?

Nitsch’s experience providing services on thousands of projects throughout the City of Boston is complemented by our understanding of the unique stormwater constraints imposed by Boston’s urban environment and historic infrastructure. For further questions or assistance with GIS and civil engineering services to support Stormwater Credit documentation, please reach out to John Schmid, PE, LEED AP BD+C, Vice President & Executive Project Manager, or any of your usual contacts at Nitsch!

For more information on the Stormwater Utility or to use the BWSC Bill Estimator to estimate your new water, sewer, and stormwater charges with rates effective on April 1, 2024, visit the BWSC website here.