Where does your sump pump water go? Check the discharge line this fall.

Your sump pump's discharge line carries water from the pit, out through the wall, and away from the foundation. If the outlet is buried in leaves, dumps water right next to the house, or runs into the sanitary sewer, the pump works harder and some of that water comes straight back. A ten minute walk around the outside of the house this fall fixes most of it before the ground freezes.

The storms on September 2 and 3 put sump pumps across Oakland County to work. They knocked out power to more than 19,000 customers in Oakland County alone, with Novi, South Lyon, and Northville among the areas hit, and overnight flooding closed stretches of I-96. Most people check the pump after a night like that. Fewer check where the water went, and that's the other half of the system. Walking the discharge line is one step in our twice a year sump pump checklist, and this is the longer version of it.

Follow the pipe

Start at the pit. The discharge pipe runs up from the pump, through a check valve, and out through the basement wall or rim joist. Go outside and find where it comes out, then follow it to where it ends. That might be a short elbow onto a splash block, a flexible extension across the lawn, a buried line to a pop up emitter out in the yard, or a connection to a storm drain.

What you're looking for is simple: water should be able to get out freely, and it should end up far enough away and downhill that it doesn't soak right back into the soil around your foundation. Water dumped next to the house finds its way back to the drain tile and into the same pit, and the pump ends up moving the same water over and over.

Leaves, lawn mowers, and pop up emitters

Fall is when outlets get buried. Leaves pile up over a splash block or pack into the opening of a pipe. A buried line that ends in a pop up emitter, the round cap in the lawn that opens when water pushes up, can get covered by leaves, grass clippings, or settled soil until it can't open. Flexible extension hoses get kinked by mowers or crushed by a car on the edge of the driveway.

Clear the outlet, make sure an emitter lifts freely, and straighten or replace any hose that's kinked. It takes a few minutes and it's the most common discharge problem we see.

How far from the house

Far enough, and downhill. Many communities and builders use about 10 feet from the foundation as a rule of thumb, but local rules vary, so it's worth checking with your city or township. Don't aim the discharge at a neighbor's yard, a sidewalk, or the driveway. Water pooled on pavement in November is ice in December.

Never into the sanitary sewer or the septic

Some older homes have the sump discharge tied into a laundry standpipe or the sanitary sewer line, usually because it was convenient at the time. It isn't allowed. The Michigan Plumbing Code says storm water can't be drained into sewers meant for sanitary drainage, because during heavy rain all that groundwater overloads the system, which is how sewage ends up backing into basements. In a home on a septic system, which is common around Milford and Highland, piping sump water into the septic floods the drain field. If your line runs into either one, it's worth rerouting.

Get ahead of the freeze

The discharge line's worst month isn't October, it's January. A line that freezes solid leaves the pump pushing against a blockage, which can burn out the motor or back water up into the basement. Before the first hard freeze:

• Make sure the line drains. Any sag that holds water will freeze first. The pipe should slope away from the house so it empties after every cycle.
• Add a freeze protection fitting. It's a fitting near the house with an opening that lets water escape if the line further out freezes, so the pump can keep working. It's an inexpensive part and worth having on any line that runs underground or across the yard.
• Pull summer extension hoses that sit in low spots, and replace them with something that drains.

We cover the rest of winter prep in our guide to keeping pipes from freezing in a Michigan winter.

While you're in the basement

Take a look at the check valve on the discharge pipe too. If it lets water fall back into the pit after the pump shuts off, the pump has to move that water again every cycle, which is one of the causes in our guide to a sump pump that runs constantly. Our sump pump page covers everything we install and repair in Milford, Novi, and Farmington Hills.

Quick answers

Where should a sump pump discharge?

Outside, far enough from the foundation and downhill so the water doesn't soak back toward the house. About 10 feet is a common rule of thumb, but local rules vary. Keep it off sidewalks, driveways, and a neighbor's yard.

Can a sump pump drain into the sewer?

Not into the sanitary sewer. The Michigan Plumbing Code prohibits draining storm water into sewers meant for sanitary drainage, because it overloads the system during heavy rain. It shouldn't go into a septic system either.

How do I keep my sump pump discharge line from freezing?

Make sure the line slopes away from the house so it drains after every cycle, remove extension hoses sitting in low spots, and add a freeze protection fitting near the house so water can escape if the line further out freezes.

Countryside Plumbing is a licensed master plumber serving Milford, Novi, Farmington Hills, and southeast Michigan since 1979. Sump pump installation, repair, and battery backups are a big part of what we do. Free quotes at 248-705-7543.