Avoid a Frozen Discharge Line

Discharge Line Frozen Solid

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If you already have a basement waterproofing system, you are likely to have a sump pump connected. That also means you have a sump pump discharge line going through the basement wall to the outside. That transition from inside to outside can be the deciding factor in how your holiday season will turn out. It is possible to get a frozen discharge line, stopping water from pumping to the outside and burning out your sump pump motor in the process.

In Connecticut and New York, the winters can get brutally cold. Temperatures in these two states can go as low as -10 to -20 degrees year after year. Planning and preparing your home for winter is essential before freezing temperatures do damage. 

Discharge Line Installation

Sump Pump Discharge Line

Generally, waterproofing contractors install a sump pump discharge line by using a 1½-inch PVC pipe connected to your sump pump, extend it high enough to go through the basement wall, and still stay 1 to 2 feet from the ground outside. At this point, it is essential to have discharged water redirected away from the home’s backfill area

Backfill Soil

A backfill area surrounds the house and extends 8+ feet. It is soft-pan soil or bulldozed dirt that is softer and more absorbent than the hard-pan soil that is untouched during the construction of the house. The trick is to get the water from the house to the hard-pan soil area.

Dry Well or Drain Field Installation

Some homes already have a way to get water 8+ feet away into the hard-pan soil area. One such installation is called a dry well or a drain field. An underground pipe that is pitched away from the house connects to a bubbler pot surrounded by a three-quarter-inch stone. The water gets absorbed into the hard-pan soil and directed away through underground capillaries.

Bubbler Pot Installation

Why Does the Discharge Lines Freeze-up?

The water coming out of the sump pump discharge line will begin to freeze with layers of ice in the middle of the night when it is colder. It will freeze shut the 1½-inch opening with solid ice. The lower layers of snow, sleet, and freezing rain on the ground will continue to melt and get absorbed into the backfill area. Cold wind and no sun will assure the pipe will remain clogged with ice. The sump pump continues to run and attempts to discharge water, but cannot.

The water pressure increases causing the sump pump motor to strain as the accumulating groundwater builds up in the clogged discharge pipe. The stress will weaken the PVC joints and cause the discharge line to start leaking or burst. Eventually, the sump pump will burn out its motor. The result is water in the basement from a dead sump pump, and possibly a pipe leak or burst.

Town or City Sewer System

If we pump groundwater into a city sewer system, discharge line freeze-ups are not a problem. The discharge line can be tapped into your septic pipe in the basement, depending on building code restrictions in your area. If you live in suburbia or city code says not to tap into the sewer line, you have another option. A unique overflow fixture is attached between the outside discharge pipe and a 4-inch dry well pipe. This connection allows water to flow when pipes freeze underground or jam up with other blockages.

Sump Pump Discharge Line Freeze Prevention

At American Dry Basement Systems, we use a fixture called Freeze-Free. We attach it close to where the sump pump discharge line exits the house wall. The groundwater temperature in Connecticut and New York consistently ranges between 44 and 54 degrees in the summer and winter. The water will not freeze as it exits the Freeze-Free fixture. The water temperature will never go below freezing, and it will melt anything within the Freeze-Free, allowing complete freedom for water to flow out.

Prevent Frozen Discharge Line

The Freeze-Free fixture is connected directly to the PVC discharge pipe and stepped up to an expander connection to the dry well pipe for a clean look. It is the best way to guard against discharge line backup and basement flooding during the winter, or anytime. If you need help with any basement waterproofing problems, give American Dry Basement Systems a call at 888-748-2002, or book a free appointment online.

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