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Our Work ยท Backwater valves

Backwater Valve Installation in Newmarket

When the street sewer surcharges in a storm, water takes the easiest way out. Without a backwater valve, that way is often your basement floor drain.

  • Pit, float, check valve and discharge checked as one system
  • Battery backup and alarm options explained plainly
  • Two full pump cycles proven before we pack up
  • Spring melt and storm calls answered first

Cues for backwater valve installation

  • Sewage has come up the basement floor drain during a downpour, even once.
  • Neighbours on your street have had backups.
  • You are finishing the basement and want to protect the flooring and drywall.
  • Your insurer asks whether a backwater valve is installed.

Basement water job sheet

Tools on the truck
Wet vac, pit cleaning scoop, PVC saw and cement, check valves, float switches
What we look at
Pit depth and liner, float travel, check valve flap, discharge route outside
What fails most
Stuck floats, seized impellers, frozen or crushed discharge lines, dead backup batteries
How we prove it
Fill the pit with a hose and watch two full on-off cycles

What fails inside the pipe, and why

Sanitary sewers are meant for household waste, but during intense summer storms extra water gets into the system through cracks and illegal downspout connections. When the main in the street fills, the pressure pushes back up every lateral. The lowest fixture in the house, usually the basement floor drain, overflows first. Homes in lower-lying pockets and older areas with combined drainage history are most exposed.

On the job: tools, parts and steps

  1. Camera the main. We confirm the lateral's path, depth and condition before we cut the floor.
  2. Open the slab. A section of basement concrete is saw-cut and dug out over the main drain, downstream of all fixtures where possible.
  3. Install the valve. A normally-open mainline valve is set level with an access cover at finished floor height giving you a way to see and rinse the flap.
  4. Re-pour and test. The trench is backfilled, the floor restored, and every fixture is run to make sure flow passes freely.

What decides how big the job gets

  • Depth of the drain and thickness of the slab.
  • Finished flooring or walls that must come up.
  • Fixtures upstream that need rerouting.
  • Permit requirements from the Town.

Shut it off and call, or book it?

If sewage is in the basement now, call for cleanup and drain clearing first, through our basement flooding service. Valve installation follows once things dry. Once it is in, look after it with the steps in our backwater valve maintenance guide. Condo-adjacent townhouses near Yonge and Davis should check with their corporation before cutting any floor.

Asked on site

Does a backwater valve end basement flooding for good?

It blocks sewage reversing up the floor drain. Seepage through foundation walls is another problem, handled by a pump, weeping tile and grading.

Can I still use my plumbing during a storm?

With the flap shut, your own wastewater has nowhere to go. Keep use light during a heavy storm so you do not flood yourself.

Do I need a permit?

A permit is generally required for this work. We help with the paperwork and inspection booking.

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