City of New York
NYC Department of Buildings (DOB) / NYC Department of Environmental Protection (DEP)
CityMS4 Phase IVerified 2026-03
Local Permit / Authorization
- Permit Required
- Yes
- Permit Name
- DOB Construction Permit with DEP Sewer Connection / Site Connection Proposal (SCP)
- Submit To
- NYC Department of Buildings (DOB) / NYC Department of Environmental Protection (DEP)
- Lead Time
- DOB plan exam 4–12 weeks depending on complexity; DEP SCP review 4–8 weeks; concurrent review possible
- Application Method
- DOB permits via NYC Buildings NOW portal (a]now.nyc.gov); DEP SCP submitted via NYC DEP portal
- Fee
- DOB permit fees based on project cost and type; DEP SCP review fee varies; combined fees can be substantial for large projects
Water Quality Standards
- Impervious Cover Limit
- No citywide cap; however, NYC stormwater management requirements trigger at ≥ 20,000 sq ft of disturbance within city boundaries (lower than state 1-acre threshold)
- On-Site Treatment Required
- Yes
- Detention Required
- Yes
- Detention Standard
- Detain/retain the first 1 inch of rainfall on-site for new development; release rate limited to predevelopment conditions; green infrastructure (bioswales, green roofs, permeable pavement) strongly encouraged by DEP
- Turbidity Standard
- Must comply with NYSDEC SPDES CGP; combined sewer areas have additional considerations per DEP's consent order with EPA
Local SWPPP / Drainage Plan
- Local Plan Required
- Yes
- Plan Name
- Site Connection Proposal (SCP) for DEP review; SWPPP per NYSDEC SPDES CGP; NYC also requires Construction Site Stormwater Management per DEP rules
- PE Stamp Required
- Yes
SCP and stormwater plans must be prepared by a NY-licensed PE or RA. NYC DEP has its own stormwater management rules (Chapter 31 of Title 15 RCNY) that are separate from and may exceed NYSDEC requirements.
Local Inspection Requirements
- Requirements
- DOB inspects construction at key milestones. DEP may inspect stormwater facilities. Sites in combined sewer areas receive additional DEP scrutiny. NYC also has a separate Construction Site Compliance program.
- Inspector Qualification
- NYSDEC-approved QI for SPDES compliance; NYC DOB licensed professionals for construction supervision
Special Overlay Zones
Combined Sewer Overflow (CSO) Area
Trigger: Properties in areas served by combined sewers (approximately 60% of NYC)
Restriction: On-site stormwater retention/detention to reduce CSO events; DEP Green Infrastructure Program incentives; sewer connection requires DEP approval
Waterfront / Flood Zone
Trigger: Properties in FEMA flood zones (expanded after Hurricane Sandy mapping updates)
Restriction: NYC Flood Resilience Zoning text amendments apply; elevated construction; wet/dry floodproofing; no mechanical systems below DFE; coastal flood protection requirements
NYC East of Hudson Watershed (DEP Watershed)
Trigger: Properties within NYC's East of Hudson drinking water watershed (parts of Westchester, Putnam, Dutchess counties — not within city boundaries but regulated by NYC DEP)
Restriction: Most stringent: ≥ 5,000 sq ft disturbance threshold; enhanced SWPPP; impervious cover limits; stormwater management per NYC Watershed Regulations; NYC DEP review and approval required
Special Natural Area District (SNAD)
Trigger: Properties in mapped SNADs (portions of Staten Island and the Bronx)
Restriction: Enhanced natural feature protection; reduced disturbance area; tree protection; additional DCP/DOB review
Design Manual
- Manual Name
- NYC DEP Stormwater Management Rules / Site Connection Proposal Requirements
Official Resources
Jurisdiction Notes
NYC has its own stormwater regulatory framework that supplements NYSDEC requirements. The city's 20,000 sq ft disturbance trigger (vs. state 1-acre) and DEP Site Connection Proposal process add a layer of local review. The combined sewer system covering ~60% of the city makes on-site retention a CSO reduction strategy. NYC's Green Infrastructure Program has installed thousands of bioswales and rain gardens in the public right-of-way.
Remember: These local requirements are in addition to the NYSDEC state construction permit. Both must be satisfied before breaking ground.
Disclaimer: This information is provided for general reference only. Always verify requirements directly with NYC Department of Buildings (DOB) / NYC Department of Environmental Protection (DEP) and the agency website before beginning construction.