Developers and contractors doing work in the City have a responsibility to protect water resources and minimize pollution from their site. Developers must meet City requirements for stormwater management following the Wastewater and Stormwater Management Guidance document, which was developed to provide guidance for development projects in the City to ensure that measures are taken to address erosion, nonpoint source pollution, stormwater quality and flood control. These measures are necessary to protect the City’s infrastructure and natural water resources. The City is also required to comply with permits issued by the U.S. Environmental Protection Agency (EPA) through their National Pollution Discharge Elimination (NPDES) programs related to stormwater and combined sewer overflows.
Wastewater and Stormwater Guidance:
In September 2026, the Cambridge Land Disturbance Regulations were revised to clarify project thresholds that determine stormwater requirements. A summary of public comment received and additional clarification in response to the comments is available here.
Under the revised Land Disturbance Regulations, projects in Cambridge fall into one of three categories for stormwater management based on project scope and size:
1. Stormwater Control Permits
2. DPW Stormwater Site Plan Review (under Building Permit)
3. Small Projects with No Cambridge Stormwater Management Requirements
Project applicants should review the September 2026 Supplemental Directive below to determine which category your project falls into and associated stormwater requirements. The September 2026 Supplemental Directive provides guidance on Cambridge stormwater standards, including sample calculations.
September 2026 Supplemental Directive to Wastewater and Stormwater Management Guidance
All project applicants should also review the DPW Site Plan Review Requirements document for submission requirements and items that must be addressed in advance of DPW sign off on the pre-approval of the Building Permit Application.
Small projects with no Cambridge Stormwater Management requirements are encouraged to use construction and landscaping projects as an opportunity to evaluate on-site drainage and make improvements. For projects of this scale, the City recommends stormwater improvements such as pervious walkways and patios, reducing impervious surfaces, dry wells, rain gardens and rain barrels. Project applicants are encouraged to review the City's stormwater site improvement recommendations and resources for projects of this size.
Stormwater Control Permits
For information regarding the Stormwater Control Permit and to apply online, click here. Refer to Appendix G below of the Wastewater and Stormwater Management Guidance Document below for checklists required for Stormwater Control Permits.
Wastewater and Stormwater Management Guidance_ Draft_May 2008
The DPW Wastewater and Stormwater Management Guidance Document is currently being updated. Until the full update is available, please refer to the September 2026 Supplemental Directive for information on stormwater requirements.
Appendix A: Best Management Practices_Draft_March 2008
Appendix B: Common Pollutants_Draft_January 2008
Appendix C: TMDL Information (superseded by Sept 2026 Supplemental Directive)
Appendix D: Technical Basis for Stormwater Quantity Guidelines
Appendix E: Example Calculations for Water Quality Control (superseded by Sept 2026 Supplemental Directive)
Appendix F: Cambridge 2070 Projected Event (Superseded by September 2026 Supplemental Directive)
Appendix G: Stormwater Control Permit Checklists_September 2019
Construction Erosion and Sedimentation Control:
When loose soil leaves construction sites, it can clog storm drains and pollute downstream rivers and streams. Developers are responsible for minimizing stormwater pollution from construction sites through the use of erosion and sedimentation best management practices (BMPs). Erosion and sedimentation BMPs must be in place prior to the start of site work and should be inspected regularly as well as before and after storm events to ensure they are functioning.
Link to City of Cambridge Erosion and Sedimentation Control Training
Link to City of Cambridge Fact Sheet for Construction Erosion Control
City of Cambridge Standard Specs and Details for Construction ESC