A communication transmitted from Yi-An Huang, City Manager, relative to Floodplain Zoning Amendments

Melissa Peters | Acting Assistant City Manager for Community Development Sandra Clarke | Chief of Administration & Operations 344 Broadway Cambridge, MA 02139 [phone removed] cddat344@cambridgema.gov www.cambridgema.gov/CDD To: Yi-An Huang, City Manager From: Melissa Peters, Acting Assistant City Manager for Community Development Megan Bayer, City Solicitor Date: March 27, 2025 Subject: Floodplain Zoning Amendments Development in the floodplain is regulated at the federal, state, and local levels of government by the Federal Emergency Management Agency (FEMA), the Massachusetts Wetlands Protection Act, and the City of Cambridge Zoning Ordinance. FEMA publishes maps that identify zones in the floodplain and mandates flood insurance for buildings located in the most critical zones. FEMA recently updated the maps for Middlesex County and requires that the City update its ordinances referring to the maps so as to remain compliant with the National Flood Insurance Program (NFIP). Additionally, the State drafted model ordinances that standardize language regulating development and require a permit for most activity in the flood plain. Section 20.70 of the Zoning Ordinance currently regulates development in the floodplain. Section 20.70, which dates to 1982, requires a Planning Board Special Permit for most development or changes to a site in FEMA flood hazard zones A and AE. Development is subject to review by the City Engineer, the Conservation Commission, and the Planning Board to ensure changes to a site will not impair the ability of the zone to carry and discharge flood waters. The floodplain regulations are different from the Flood Resilience Standards in Section 22.80 of the Zoning Ordinance, adopted in 2023. Rather than FEMA maps, this section is grounded in the City’s long-term flood elevations for 2070, which cover broader areas of Cambridge and are updated over time by DPW. Development subject to the proposed amended Section 20.70 must meet performance standards for flood protection that are reviewed by the City Engineer. The Wetlands Protection Act, passed in 1972, supplements requirements in zoning and building codes to manage flooding, prevent pollution and storm damage, and protect public and private water supplies, groundwater supply, fisheries, land containing shellfish, and wildlife habitat. The Cambridge Conservation Commission reviews and permits projects seeking to alter a wetland resource area and can attach conditions to its approval. Currently, activity in the floodplain requires separate public hearings and approvals by the Conservation Commission and the Planning Board, although the Planning Board typically defers to the Conservation Commission on matters under the Commission’s jurisdiction.

Melissa Peters | Acting Assistant City Manager for Community Development Sandra Clarke | Chief of Administration & Operations 344 Broadway Cambridge, MA 02139 [phone removed] cddat344@cambridgema.gov www.cambridgema.gov/CDD The proposed zoning text amendment will replace Section 20.70 of the Zoning Ordinance with the Massachusetts model ordinance structure and will reference the updated FEMA maps. The new text will replace the Planning Board Special Permit with an administrative review that will maintain the current criteria for approval while removing the duplicative hearing process for many cases. A Planning Board Special Permit may still be required if it is otherwise triggered, such as for Project Review (Section 19.20), Planned Unit Development (PUD), or development in the Alewife Overlay Districts. These changes will update the Zoning Ordinance to be compliant with the NFIP and to be consistent with state law while removing one step in a complex approval process. The proposed zoning text does not affect the Flood Resilience Standards in Section 22.80 - these will continue to require new development to comply with standards that protect against future flood risk citywide. The flood plain can be viewed on FEMA’s website via an interactive map that shows the six panels that apply to Middlesex County at the following link: https://msc.fema.gov/portal/search. We recommend that the attached zoning text be adopted as a City Council Zoning Petition and referred to the Planning Board and Ordinance Committee for hearing and report.