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Stormwater Management
Stormwater is the rain and melting snow that falls on our rooftops, streets, and sidewalks. As stormwater flows, it sweeps up pollutants such as oils, chemicals, sediments, pathogens and trash. Rather than being absorbed naturally into the ground, much of New York City’s stormwater eventually flows into storm drains or catch basins, and from there into the Sewer System.
We oversee a broad citywide effort to better manage stormwater to improve the health of our local waterways and prevent flooding. Learn more about our Municipal Separate Storm Sewer System, Green Infrastructure, Bluebelt, and Long Term Control Plan Programs, as well as what you can do to protect local waterways with the Safe Disposal of Harmful Products.
To receive the latest information about our events and activities, visit Newsletters and subscribe to the “DEP Stormwater” email list.
Unified Stormwater Rule
The Unified Stormwater Rule (USWR) changed requirements related to how stormwater is managed on new and redevelopment properties across NYC. The rule requires updated stormwater quantity and flow rates for site and house connection proposals and a retention-first approach for projects that need MS4 Construction Permits.
Stormwater Management System Design Guidelines
Guidelines for the Design & Construction of Stormwater Management Systems
The Guidelines for the Design and Construction of Stormwater Management Systems assists New York City’s development community and licensed professionals in the selection, planning, design and construction of onsite source controls.
- Download the Guidelines for the Design and Construction of Stormwater Management Systems
- Download the Overview of the Guidelines
Standards for Stormwater Release Rates
View the rules governing house and site connections to the city’s sewer system: Chapter 31 of Title 15 of the Rules of the City of New York (RCNY).
Water and Sewer Forms
We’re responsible for approving all work related to the City water and sewer infrastructure including construction of private water and sewer mains, connections to the water and sewer system, repair work on the system, and discharges into the sewer system. This section includes general information and detailed application requirements to assist property owners, Professional Engineers, Registered Architects, and Licensed Master Plumbers in obtaining required approvals, permits and inspections.
Southeast Queens
The Interactive Southeast Queens Project Map highlights projects that are in construction or have been completed as part of the City’s $1.9 billion effort to reduce flooding and upgrade infrastructure throughout Southeast Queens.
Protecting Your Home from Sewer Backups
Tools to Prevent Basement Sewer Backups and an Evaluation of Backwater Valves
2024 Stormwater Analysis
DEP is starting the complex work of re-evaluating how the stormwater management system is designed.
Rainfall Ready NYC
A plan to prepare the city government and New Yorkers for more extreme rainfall in the future
Cloudburst Management
A way of absorbing, storing, & transferring stormwater to minimize flooding from heavy rain events.