Avoid Frozen Sump Pump Pipes

Updated: Feb. 14, 2024

What seemed like an easy, inexpensive project could have turned out to be a costly disaster.

Sump_pipes_4_17_13 avoid frozen sump pump pipes

Last fall I tackled a little project that could have caused me big problems. The previous spring, I had a drain tile system installed in my basement. The system discharges outside through a sump pump discharge pipe, and I quickly tired of looking at that ugly black extension hose sticking out the side of my house. I decided to bury a pipe to carry the water out near a rock garden about 20 ft. from the house. What seemed like an easy, inexpensive project could have turned out to be a costly disaster.

If your sump pump’s discharge pipes are buried, leave a gap between the pipes. That way the water will still be able to discharge from the upper pipe even if the one in the ground is frozen.

My idea was to extend the existing 1-1/2-in. pipe down into a 4-in. pipe buried 1 to 2 ft. underground. As luck would have it, my brother-in-law paid us a visit while I was digging my trench. He asked what was going to happen when the pipes froze in the winter. Unfortunately, I hadn’t thought of that, and every answer I could come up with involved water flooding my basement.

He explained that the wise old plumber who worked on the house he recently built had left a gap between the pipes, so when the water does freeze it still has a place to go. Not that I didn’t believe my brother-in-law (ahem), but I called the company that installed my drain system to see if this was a sound plan. They agreed and told me that if I had finished my original design, the pipes would have likely come apart at the check valve connection, or I would have burned up my pump. The company said they get dozens of calls a year from people who neglect to remove the extension hose in the winter, which causes similar problems. They kindly reminded me they told me as much both verbally and in a pamphlet, but I didn’t mention that I had completely forgotten about that little tidbit.

I also asked the pros about the water that discharges near the house instead of out in my yard. They said most pumps don’t run in the winter (which was true at my house), and that a little recycling of water for a couple of weeks in the spring was better than the alternatives: digging a 4-ft.-deep trench to get below the frost line, or having water in my basement. I couldn’t argue with that. So it turned out that my brother-in-law saved my skin. It almost makes up for all those years of him drinking my beer…well, almost.