At a Glance

New York City uses green roofs to reduce stormwater volume, support the restoration of Jamaica Bay, improve urban ecology, and create educational opportunities.

Project Description

Much of the pollution in New York City’s Jamaica Bay comes from overflow that occurs when heavy rains overwhelm the City’s combined stormwater/sanitary sewer systems. To address this problem and support the restoration of Jamaica Bay, the New York City Department of Environmental Protection (DEP) has committed to reducing stormwater volume. As one component of this effort, DEP is targeting 10% of the City’s impervious areas for treatment of rainfall by 2030.

Recognizing the ability of green roofs to capture rainfall, slow runoff, and provide opportunities for evapotranspiration, particularly in densely developed watersheds, DEP sought assistance in exploring the feasibily of city-wide green roof implementation. Biohabitats prepared an internal report for DEP on the Jamaica Bay Watershed which examined existing green roof projects, provided conceptual planning of multiple implementation strategies, defined the holistic benefits of green roof systems, and investigated life cycle costs. The report serves as planning tool for DEP as to the applicability and benefits of green roofs in the Jamaica Bay Watershed.

Biohabitats also helped create a New York City stormwater management design manual, which documents appropriate design and construction procedures for green roofs and other surface and subsurface detention devices. As part of this effort, Biohabitats performed a code review to determine critical factors to consider in green roof retrofits.

Biohabitats is currently designing a green roof system for a New York City public school as part of the City’s stormwater pilot program. The site will not only retain stormwater, but also provide a hands-on opportunity for students, faculty, and the surrounding community to learn about green roof technology, urban ecology, and how human actions can impact the environment.



Hudson River

Physiographic Province

Coastal Plain


New York City Watershed

Expertise Areas

Design & Build, Infrastructure, Research & Development, Urban Ecology, Water


New York City Department of Environmental Protection


New York City, New York, United States

Project Team
  • Hazen & Sawyer
  • HDR