Connecticut Commercial Stormwater General Permit – School Registration Requirements

Schools in Connecticut may be receiving notifications regarding the requirement to register under the Connecticut Department of Energy and Environmental Protection’s (CT DEEP) Commercial Stormwater General Permit (Commercial GP) by December 1, 2026. However, municipally owned or operated schools in communities registered under Connecticut’s General Permit for the Discharge of Stormwater from Small Municipal Separate Storm Sewer Systems (MS4 GP) may be exempt from registering under the Commercial GP.

CT DEEP has confirmed to Barton & Loguidice (B&L) that public schools owned by municipalities covered under the MS4 GP are likely exempt from the Commercial GP. This potential exemption is based on the maintenance requirements outlined in Section 6(a)(6)(C) of the MS4 GP and the exemption provisions of Section 3.1.5 of the Commercial GP.

Section 3.1.5 of the Commercial GP states that sites where all stormwater discharges are authorized under another National Pollutant Discharge Elimination System (NPDES) permit, including the MS4 GP, are not required to obtain authorization under the Commercial GP.

Section 6(a)(6)(C) of the MS4 GP applies to municipally owned or operated properties, including schools that may not be directly connected to the larger municipal storm sewer network. Accordingly, these properties remain subject to applicable MS4 maintenance requirements and may qualify for the Commercial GP exemption.

An important consideration in determining whether a school qualifies for this exemption is the municipality’s responsibility for maintaining the school property. If a municipality registered under the MS4 GP is legally responsible for maintenance activities, such as street sweeping and catch basin cleaning, or has an agreement to provide these services, CT DEEP considers the school a permittee-operated property. Conversely, if the municipality does not retain responsibility for these maintenance activities, the school may be subject to the Commercial GP, provided it meets the other applicable eligibility requirements, including a 5-acre impervious surface threshold.

MS4 Compliance Requirements for Schools

Like other municipally owned or operated facilities, schools covered under the MS4 GP must comply with applicable permit requirements. Section 6(a)(6)(C) includes the following measures to help minimize potential stormwater pollution:

• Evaluate the use, storage, and disposal of petroleum and non-petroleum products.
• Provide employee training to ensure personnel responsible for handling these products understand proper procedures.
• Ensure Spill Prevention Plans are in place, where applicable, and coordinate with the local fire department as necessary.
• Develop management procedures for dumpsters and other waste management equipment.
• Sweep parking lots and maintain clean areas surrounding school facilities to minimize pollutants in stormwater runoff.
• Ensure that interior building floor drains are not connected to the MS4.

Schools should maintain documentation of activities conducted to demonstrate compliance with these requirements and include applicable information in annual MS4 reporting.

How Barton & Loguidice Can Help?

Barton & Loguidice can assist municipalities and school districts in evaluating permit applicability, developing maintenance and inspection plans, conducting facility inspections, providing employee training, and addressing other stormwater compliance requirements.

For questions regarding compliance with Connecticut’s Commercial GP or MS4 GP, please contact our Hartford office at (860) 633-8770 or T.J. Therriault, P.E.