Flap Valves HDPE - Water Control

HDPE Flap Valves may be Round, Rectangular or Square design.

Low door opening head pressure.

Back flow prevention during high water events, floods high tides. Designs for headwall mounting, flange mounting, or end pipe connections.

Flap Valve Wall Mount "G" model



Flap Valves: WA-PTKG

Pressures standard: 1 Mwc
Flood conditions: 5 Mwc for 72 hours
Higher pressures available.

Flush mounted to a headwall.

Sizing: 100mm to 1500mm
Larger sizing on request.






Flap Valve Flange mount "F" model



Flap Valves: WA-PTKF / 10 degree door

Pressure standard: 1 Mwc
Flood conditions: 5 Mwc for 72 hours
Higher pressures available.

Flap valves bolt to a the pipe discharge flange.

Sizing: 100mm-1500mm
Larger sizing on request




Flap Valve Wall mount "A" model



Flap Valves: WA-PTKA / 10 degree door

Pressure standard: 1 Mwc
Flood conditions 5m for 72 hours
Higher pressures available.

10 degree flap valve doors mounted to a headwall

Sizing: 100mm - 1500mm
Larger sizing on request





Flap Valve - pump line with vent WA-PWK-F model


Flap Valves : WA-PWK-F (Pump Pressure lines with vented connection)

Pressure standard: 1 Mwc
Flood conditions: 5m for 72 hours
Higher pressures available.







HDPE Flap Valve for mouning on end of pipe


End pipe mounted Flap Valves WA-PTK-BS

Pressure standard: 1 Mwc
Flood conditions: 5m for 72 hours
Higher pressures available.

Flap valve spigit mounts in the end of a pipe outfall.

Sizing: 150mm to 2000 mm
Larger sizing on request



Install Video



Flap Valve and Penstock Combination flow control model WA-POTK-G


Down position: as a Flap Valve
Lifted position: Free flow

Waterhead Standard: 1 Mwc
Flood conditions: 5 Mwc waterhead 72 hours
Higher pressures available.

Contact Westatlantic for sizing
1-902 455-4455






In-line Penstocks Inside pipe mounting.

See Penstocks and Sluice gates

Flap Valves protect against backup during high water events. The doors open to allow flow to begin with very low water head and withstand against high head pressures.


Flap valves operate automatically to discharge water and close automatically to stop back flow. Rising waters from flooding or tidal conditions are prevented from entering a drainage system. HDPE Flap Valves weigh less than metal units and are virtually maintenance free.

Any metallic materials in HDPE flap valves use 316L stainless steel - for example 316L stainless for hinges, door hooks balancers and reinforcement bars. 316L stainless steel offers corrosion protection for long life operations.

Download cut sheet Introduction To HDPE Flap Valves


Flap valves, protection infrastructure from storm damage. They prevent back flow through discharge pipes, protect low level lands and building structures from flood waters.

Standard HDPE flap valves may be covered by one meter water column on a continuous bases and in the event of flood conditions five meters of water head for up to 72 hours. Higher pressures are available.

Doors open for one way flow with just a few millimeters of deferential pressure.

- Prevents back flow from high tidal waters.

- Prevents flooding from storm events.

- Discharges waters to tidal inlets, ditches, manholes, culverts, reservoirs, ponds, and basins.

- Flap Valves are flow control valves that allow outflow of water while preventing back flow.

- Flap Valves can be used on 4" diameter pipe (100 mm) and up.

- HDPE flap valves require very low opening pressure.

- When water on the face side of the flap door rises above water on the back side, the watertight door closes to prevent back flow.

- Flap Valves may be installed above the waterline or below the waterline.

- HDPE (High Density Polyethylene) Flap Valves, are lightweight, corrosion resistant non-return check valves for the prevention of flood damage.

General Installation Instructions Wall Mount HDPE Flap Valves



Available for all American and International pipe sizes
All pipe materials: PVC - Ductile Iron - Concrete - HDPE

Westatlantic Tech Corp, Contact or 902 455 4455






Introduction to HDPE Flap Valves

HDPE flap valves are commonly used in water flow, sewage and wastewater systems. They are designed to allow fluids to flow in one direction while preventing back flow in the opposite direction. HDPE (high-density polyethylene) is a type of plastic that is durable and resistant to chemical and environmental factors, making it an ideal material for the construction of flap valves.

Flap valves consists of a hinged flap door that swings open in the direction of fluid flow, allowing the fluid to pass through. When the fluid flow stops, the flap swings back to its original closed position, creating a seal that prevents back flow. HDPE flap valves are typically used in applications where there is a risk of flooding or backup, such as in storm-water management systems or in treatment plants.

HDPE flap valves main benefits is that they are lightweight and easy to install. They are also resistant to corrosion, erosion, and UV radiation. Making them a durable and long-lasting solution for sewage and wastewater systems. Additionally, HDPE flap valves can be customized to fit specific pipe diameters and flow rates, making them a versatile solution for a range of applications.


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Flap Valves, hdpe, floods, flood control, rising ocean levels, river overflows, river levels, storm events, Penstocks, Sluice Gates, stop logs, Weirs, Float Valves, Flood Gates, stainless steel, 316L: USA and Canada; USA: Louisiana, LA, Alabama, AL, Mississippi, MS, Texas, TX, Ohio, Illinois, PA, South Carolina, SC, North Carolina NC, Wisconsin, WI, Milwaukee. Canada: Alberta, AB; Edmonton, Calgary, British Colombia, BC; Vancouver, Saskatchewan, SK; Regina, Saskatoon, Manitoba MB; Winnipeg, Ontario, ON; Oakville, Toronto, Mississauga. Quebec: QC; Montreal, New Brunswick, NB, Nova Scotia, Newfoundland Labrador, NL.