NYC DEP Approved Valves: Knife Gate, Plug Valve, Ball Valve Specifications for Water and Wastewater

The New York City Department of Environmental Protection (NYC DEP) operates and maintains one of the largest and most complex municipal water and wastewater systems in the world. The NYC DEP Bureau of Water Supply and Bureau of Wastewater Treatment collectively manage more than 7,500 miles of water mains, 6,800 miles of sewer lines, 14 wastewater treatment plants processing 1.3 billion gallons per day, and the Catskill/Delaware/Croton watershed system providing clean drinking water to 9+ million people in NYC and surrounding counties.

NYC DEP Valve Procurement Framework

NYC DEP procures valves through two primary channels: the New York City Department of Design and Construction (NYC DDC) for capital infrastructure projects (water main replacements, sewer rehabilitation, new treatment plants), and direct DEP procurement for MRO (Maintenance, Repair, and Operations) replacements and emergency repairs. All valves used in NYC water supply and distribution must comply with NSF/ANSI Standard 61 (Drinking Water System Components — Health Effects) to ensure no harmful leaching of materials into potable water. The key valve specifications referenced in NYC DEP project documents are:

NYC DEP Knife Gate Valve Specifications

Knife gate valves are widely used in NYC's wastewater treatment plants for sludge handling, grit removal, primary and secondary clarifier operations, and digester systems. NYC DEP specifications for knife gate valves typically require:

• Body material: Ductile iron (ASTM A536 Grade 65-45-12) for standard wastewater service; SS 316 for corrosive chemical or digester gas service
• Gate (knife) material: SS 304 or SS 316 — smooth ground finish to minimise solids buildup; tungsten carbide edge coating for abrasive slurry with high solids content
• Seat: EPDM or NBR full-circumference resilient seat for wafer-type; metal seat (SS 316) for high-temperature digester steam service
• End connection: Wafer, lug, or flanged ANSI Class 125 / ANSI Class 150 (matching ductile iron flanges common in NYC water/wastewater piping)
• Pressure rating: 150 psi (10.3 bar) working pressure for standard wastewater; 200 psi for sludge pump discharge service
• Operator: Handwheel or gear operator for manual operation; pneumatic or electric actuator for remote-operated knife gate valves in SCADA-controlled treatment plant systems
• Standards: AWWA C520 (Knife Gate Valves — Sizes 2 through 96 Inches) is the key standard for NYC municipal knife gate valves

NYC DEP Plug Valve Specifications

Eccentric plug valves are the primary on-off and throttling valve specified by NYC DEP for wastewater and combined sewer overflow (CSO) applications. The eccentric plug valve (vs. standard lubricated plug) is preferred because it does not require periodic lubrication and handles wastewater solids without clogging. NYC DEP plug valve specifications:

• Type: Eccentric plug valve (non-lubricated) — plug offset from seat centreline; plug retracts away from seat on opening without rubbing
• Body material: Ductile iron (ASTM A536) with fusion-bonded epoxy coating (AWWA C550) inside and outside for corrosion protection
• Plug material: Ductile iron with neoprene or EPDM facing bonded to plug face — provides tight shut-off against the metal seat ring
• Seat: Stainless steel (SS 316) seat ring pressed or welded into the body — smooth, hard seat the plug presses against on closure
• Sizes: 2" to 48" (DN 50 to DN 1200) — eccentric plug valves are practical at large sizes where ball valves become prohibitively expensive
• Pressure class: AWWA Class 150B (175 psi WP at 100°F) standard; Class 250B available for higher pressure service
• Standards: AWWA C517 (Resilient-Seated Cast-Iron Eccentric Plug Valves); ANSI/AWWA C504 for rubber-seated butterfly valves used in similar service
• Actuation: Gear operator (manual) or pneumatic/electric actuator; SCADA integration for DEP's remote monitoring and control system

NYC DEP Ball Valve Specifications

Ball valves in NYC DEP service are used for smaller-bore (1/2" to 4") isolation service in water treatment chemical dosing, instrument isolation, sample connections, and compressed air systems. Larger bore ball valves (4" to 24") are used in pumping stations and storage tank isolation. NYC DEP ball valve specifications:

• NSF/ANSI 61 compliance: Mandatory for all ball valves in potable water contact — body, ball, seat, and packing must all comply with NSF 61 leaching requirements
• Body material: Bronze (ASTM B584) for sizes 1/2" to 2" in potable water; ductile iron (ASTM A536) for sizes 2" to 12"; SS 316 (ASTM A351 CF8M) for chemical dosing and corrosive service
• Ball material: SS 316 — chrome-plated CS balls are not acceptable for NYC water service (chromium leaching concerns)
• Seat: PTFE (polytetrafluoroethylene) or RPTFE (reinforced PTFE) — NSF 61 listed; EPDM for low-pressure water service
• End connection: Threaded NPT for 1/2" to 2"; flanged ANSI Class 125 / Class 150 for 2" and larger
• Standards: AWWA C507 (Ball Valves, 6" through 48") for large-bore service; MSS SP-110 or API 608 for smaller bore instrument and utility ball valves
• Lead-free compliance: All potable water ball valves must comply with NSF 372 (Drinking Water System Components — Lead Content) — wetted surfaces ≤ 0.25% weighted average lead content

AWWA Standards Referenced by NYC DEP

Vajra Industrial Solutions can supply knife gate valves, eccentric plug valves, and ball valves meeting AWWA C517, C520, and C507 specifications for municipal water and wastewater projects in New York and across North America. All valves are supplied with NSF/ANSI 61 compliance documentation, hydrostatic test certificates, and full material traceability. Contact sales@vajravyuh.com for specifications, availability, and pricing.