DEP — Department of Environmental Protection

The New York City Department of Environmental Protection (DEP) manages the city's water supply, wastewater treatment, and environmental regulatory programs. DEP oversees the largest municipal water supply system in the United States, delivering over one billion gallons of drinking water daily to 8.3 million New Yorkers.

For property owners, DEP is significant because water and sewer charges are billed directly to the property — and unpaid charges are included in the annual NYC tax lien sale, making them a critical due diligence concern.

DEP's regulatory scope includes:

• Water supply and metering for all NYC properties
• Sewer service charges and infrastructure
• Stormwater management and Green Infrastructure program
• Environmental site assessments and contamination tracking
• Noise Code enforcement
• Air quality monitoring and compliance
• Hazardous materials regulation

DEP issues violations and charges including:

• Unpaid water and sewer charges — billed quarterly, follow the property
• Illegal sewer connections
• Stormwater management violations
• Noise Code violations (construction and commercial noise)
• Air quality violations
• Backflow prevention device non-compliance

DEP permits include sewer connection permits, stormwater management plans, and construction dewatering permits.

DEP penalties vary significantly by violation type. Water/sewer charges accumulate with interest (currently 9% per year). Critically, unpaid water and sewer charges exceeding $1,000 are included in the annual NYC tax lien sale — meaning a private lien buyer can charge 18% interest and eventually foreclose. Environmental violations can carry fines of $1,000 to $25,000 per day depending on severity.

RegWatch includes DEP water/sewer charge data in property profiles and flags outstanding balances as potential lien risks. Environmental site data from DEP, including brownfield status and contamination records, is included in our environmental risk assessment. Portfolio monitoring alerts you to escalating DEP balances before they reach lien sale thresholds.