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Discharge Line

Your sump pump alone won’t move water out of the basement. It needs a discharge pipe that goes to the outside.

When homeowners talk about flooding protection, they focus on the sump pump and forget the discharge line. This line completes the jigsaw enabling the sump pump to do its job. If you’re setting up a sump pump and wondering what’s all the fuss with the discharge line, read on. We’ll describe what a discharge line is, what it does, and show you how to protect yours in winter. 

What Is a Discharge Line? 

A discharge line is a pipe that’s attached to the sump pump. Contractors prefer PVC pipes as they are sturdy and rust resistant. 

It’s directed to the home’s exterior and can be buried in the ground like downspout extensions. Once the discharge pipe is directed outside, it should extend far from the foundation and run downhill to stop backflows to your sump pump. To prevent backflows, the discharge point has to be 10 feet from the exit. Many homeowners direct their discharge lines to nearby streams or street drains. 

Ideally, the discharge pipe should be at least two feet below the frost line in your area. This will prevent water in the pipe from freezing, which can lead to clogs. It will also be easier for you to dig and open up the pipe if there’s a problem. 

One benefit of installing a discharge line is that it enables the sump pump to function properly. This pipe will move water out before it damages your belongings or hurts your foundation. 

Discharge Pipe Installation 

Installing a discharge pipe is a pretty simple thing. Typical installations go like this: 

  • The contractor sets the sump in the basin ensuring it is level and resting properly. 
  • A 3 or 4-inch PVC pipe is connected to the discharge hole on your sump pump using PVC cement or a male adapter. 
  • To prevent airlocks, a ¼ inch hole is drilled on the PVC pipe just six inches above the sump pump outlet. 
  • A vertical check valve is installed on the discharge line above the weep hole. This device stops water from draining back to the pump. 
  • Next, a hole is drilled through the wooden rim joist on your basement wall. The drain pipe will exit your home through it. 
  • The contractor extends and directs the pipe with additional pieces of the PVC pipe and then secures the fittings with PVC cement. 
  • Once the line reaches the exit hole, the opening around the discharge line is sealed with silicone caulk. This will lock out water and moisture. 
  • A sloping trench is excavated if the drain pipe has to go underground. 

Benefits of a Sump Pump Discharge Line 

The discharge line has to be wide enough to hold all the water that the sump pump ejects from the basement. Some sump pump installations overwhelm discharge lines by trying to move out more water than the pipe can hold, which leads to sump pump backups and failures. 

Discharge points are vulnerable to dirt and debris. You have to protect them from freezing water and the best safeguard is installing a FreezeGuard™ attachment. What this does is add a drain to the base of your home to protect the pump from backing up in case ice or snow clogs the discharge point. 

A sump pump check valve is a vital addition. Without it, water would fall back to the sump pit each time the pump shuts off and the pump would have to eject it again. Over time, this will increase the sump pump’s wear and tear, which can lead to burnout or failure. 

Can You Discharge into the Public Sewage System? 

Homeowners used to direct their sump pump discharge lines into the sewers. In turn, sewers became inundated with water from sump pumps during downpours, and laws were passed to minimize the pollution of waterways. These laws made it illegal to direct sump pumps discharge into public sewers. 

If you need help installing a sump pump, its discharge line, and a failsafe to protect your system, contact the basement waterproofing experts at JES Foundation Repair

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