NYC Basement Flood Mitigation Study

BJH Advisors, in partnership with Thornton Tomasetti, supported the New York City Department of Housing Preservation and Development (HPD) on the Basement Apartment Flood Mitigation Study, focused on assessing flood risks and evaluating mitigation strategies for legalizing basement dwelling units in vulnerable neighborhoods across New York City.

BJH Advisors led stakeholder coordination and outreach to support resident participation and data collection efforts. The team developed outreach strategies tailored to communities with varying levels of flood exposure and housing vulnerability, coordinating closely with community-based organizations, residents, and agency partners.

The team also developed a benefit-cost analysis framework to evaluate the economic viability of proposed mitigation measures. BJH assessed avoided flood damages, displacement risks, and broader social and resilience benefits associated with flood mitigation investments. Through this work, BJH Advisors contributed to the City’s broader efforts to improve climate resilience, advance housing safety, and support pathways to legalizing basement dwellings in vulnerable neighborhoods.