Backwater valve installation in Mississauga and All GTA by Mister Plumber

Call our fully-licensed, insured and experienced Mississauga plumbers at 416 939 1530 The only Reliable and Trustworthy option.

Fullport Mainline backwater valve

Installing a backwater valve will prevent sewer drains from backing up and overflowing with sewer water – eliminating sewer backflow as a source of basement flooding.

Backwater Valve installation in Mississauga

A backwater valve is a one way flow control valve installed in a drainage system, that under normal conditions allows the waste water to drain out of the system but if a reversal of flow should occur, the valve will be forced closed and protect the interior of the building from sewage backup. Every year thousands of homes are flooded with raw sewage and storm water causing millions in damages that could have been avoided with properly installed backwater valves.

When are backwater valves required

backwater valve installation toronto mississauga gta plumberBackwater valves are required to protect fixtures and drainage openings that are installed below grade; such as in a basement, where the possibility exists for the municipal sewage or storm water systems to become overloaded and force waste water back through your drains. Backwater valves are also required on any subsoil drainage pipe that connects into the sanitary drain, to protect it from sewage backups.

The most common backwater points of entry into your home may be through basement floor drains, water closets, sinks, laundry standpipes and sump pits.

Fullport Backwater Valve

The Mainline #4963 Full-Port Backwater Valve is the ‘flagship’ of the company. Established in 1997, this valve has revolutionized sewer protection across North America with its patented ‘normally open’ gate design. This valve is typically installed in homes or buildings that have basements, cellars, crawl spaces or area that are accessible for servicing. The normally open gate allows the sewer system to ‘vent’ any gases that may be causes by positive or negative pressures in the sewer line. The 4963 has a ‘Clear View’ top that m

Toronto-Backwater valve with access box

akes inspection of the valve quick and simple for the building owner or plumber! As well, the 4963 comes with an integral clean-out for rodding the sewer lateral. Should rodding from the stack be necessary, the snake can easily pass over the open gate and be retracted with out doing any harm to the components.

How to Reduce the Risk of Basement Flooding

Flooded basements can result in expensive repair bills and heartaches for homeowners. Learn how a backwater valve, installed below the floor in your basement, and other preventive measures can help reduce your risk of flooding and protect your valuables.

Features and benefits:

  • “Normally-open design” offers zero flow restriction
  • “Normally-open design” allows free circulation of air through the Plumbing System
  • “Clear Lid” easy visual inspection of unit
  • “Built-in main-sewer cleanout”   allows auguring of sewer


What keeps the valve Clean?

Plumber Backwater valve installation in Toronto GTA

Gate has 2% built in grade in the design

Bottom of gate on body has 4% built in grade in the design

Side Channels have 8.25% built in grade in the design

With the valve installed at 2% minimum grade as per installation instructions!

Results: Gate – 4% grade

Body – 6% grade

Channels – 10.25%

Toronto-Backwater valve installation outsideFlow Channels:

Flow channels prevent sewage from penetrating gate and valve bottom and float area upon normal flow conditions

Built in flow channels on gate direct sewage out onto body

Built in flow channels on body direct sewage out of body

How Hinge area is protected from contamination

At the bottom of the valve you will notice dams, the gate in the open position rests on these dams preventing any flow from circling back from the outlet side of the gate and penetrating back into the hinge area,

At the front of the dams is drain port, this port drains away any water which may seep under the gate through the inlet side of the valve

Gate Function

plumber-install-Backwater-ValveGate is fitted with closed cell polyethylene floats, this flotation material is impervious to sewage and will not become water logged (gate design locks floats in place)

Upon a slow reversal flow, water rises in the body and the gate starts to float (lift). Once the gate starts to lift the water flow in turn pushes the gate into the gate position.

Upon a quick reversal: The gate is fitted with 45 degree angles on the front which act as wings, upon quick reversal action water is diverted into the wing area through the flow channels. Water then pushes up on the 45 degree angles causing the gate to quickly close.

O-ring is used on the body for positive seal.

Built-in Sewer Cleanout

The built-in sewer clean out is downstream of the gate, a sewer tape will not catch on the gate when feeding or retrieving the cable

Bolted Gasketed Cover

Nuts and Bolts are Stainless Steel

Polycarbonate transparent lid provides a visual inspection of the unit at all times

Demo of Sewer Backflow Prevention Device at ACE

Toronto-Backwater valve with two clean-outsThe City of Mississauga currently actually requires all homes to have a backwater valve. And the city goes further. It offers grants and rebates to homeowners. Mississauga’s flooding protection program will pay an 75% rebate on the invoiced cost of backwater valve installation in Mississauga, up to a maximum of $1,250. The city of Vaughan has a program that rebates 50% of the invoiced cost, up to a maximum of $750. Eligible expenses include labour, materials, permit fees, and taxes.

Can you help me to claim my backwater valve rebate?

Yes. As fully licensed, and insured Mississauga plumbers we are qualified to help you claim your City of Toronto flood prevention rebate. We have installed many backwater valves in Mississauga and fully document the process to help you expedite your flood prevention rebate claim.

Upon customer’s request Mister Plumber can install new and improved backwater valve ML-FR4!

Give us a call today we offer a top notch service for a great price!


Mister Plumber with 15 years plumbing experience are Mississauga Licensed Plumbers and Drain services company. Our plumbing company specializes on plumbing and drain systems services in Toronto, Mississauga, Scarborough, North York, Etobicoke, Oakville and GTA.

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