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Return to "Non-Return and Backwater Valves"

In-Line Backwater Valves

A range of single-flap and double-flap valves for installation onto sewerage pipes

Capricorn NRV 110 webProtect buildings against backwater flooding due to rainwater travelling back up the sewerage system.

Automatically operated, providing free-flow wastewater drainage according to the slope of the rainwater drain. These backwater valves are available in a wide range of sizes and are easy to install in waste water networks and systems with pipes of Ø110 to Ø200.


  • Backwater valves are 100% tested for safety and comply with the guidelines set out in BS EN 13564
  • Robust design and maintenance-free operation


  • Stainless steel anti-flooding flaps
  • Special design of the body minimises the risk of solid waste accumulating and blocking inside the valve
  • Also suitable as a rodent deterrent

Backwater Valves, Single Flap


Suitable for stormwater applications

Product Code 
ø (mm)
Height (mm)
Width (mm)
Length (mm
Weight (Kg)
BWV110/1 110mm Backwater Valve 110 200 190 310 1.42
BWV160/1 160mm Backwater Valve 160 260 235 340 2.3
BWV200/1 200mm Backwater Valve 200 353 304 560 6.6

Capricorn Single Flap

Backwater Valves, Double Flap

Suitable for foul sewerage systems

Product Code
ø (mm)
Height (mm)
Width (mm)
Length (mm)
Weight (Kg)
BWV110/2 110mm Backwater Valve 110 195 205 395 1.86
BWV160/2 160mm Backwater Valve 160 273 304 577 5.05
BWV200/2 200mm Backwater Valve 200 353 304 560 7.5

 Capricorn Double Flap