Fun with sump pumps

[Tom Raymond]

Yesterdays inspection was a 1930ish single family with most of it's original charm intact, and all new plumbing and electrical work. The electrics had a sticker indicating the company that did the work, good thing since I now know who not to call. No such luck on the plumbing. Most of it looked to be professionally done, but the hack work used all the same material and looked to be about the same age.

Someone decided that since there was a sump pump they didn't need a lift pump for the basement laundry, and since there using the sump pit they didn't need any traps. Then some dummy decides that it will be easier to drop the dishwasher drain through the floor and cob together a bunch of parts to drian it with the washing machine rather than get the correct tail piece and connect it properly. I wish I had a pic of this, but the RE distracted me with something else and I forgot to shoot it.

As if this wasn't bad enough, take a look at the sump plumbing and tell me if you can figure out what the hell they where thinking.

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The open tee is about 3/4" from the subfloor, which is damp there. This pipe extends into the sump pit and stops about 2" above the high water mark in the pit. The line it connects to at the top is the drain from the kithchen sink. I reported "I cannot figure out any purpose for this arrangement other than to vent these (sewer) gases into the basement."

The pipe on the right is the sump drain. It connects to the kitchen sink drain just out of the shot, with a similar configuration of elbows, but without the open tee. I reported it as being improperly supported, and incorrectly used as a lift pump, and that it is posible for sewage to back up into the sump pit.

I know the sump is supposed to be drained to daylight or connected to the storm sewer, but I cannot find the reference the prevents it from being plumbed into the sanitary sewer. Thanks for looking.

Tom

I hope you enjoy it as much as I did.

[Jim Katen]

I think you're looking at it backwards. If this pit receives discharge from the washing machine, then isn't it really a poorly designed sewage ejector?

- Jim Katen, Oregon

[Tom Raymond]

I originally used that wording, but revised it to lift pump because it is handling grey water from the laundry (and DW) and not solid waste. It's pretty common around here for a basement laundry to have an enclosed float actuated lift pump under the utility tub. What ever you call it, it should have backflow and shut off valves in it. Besides, it has to be a voilation of something more than common sense to dump contaminated water into groundwater before pumping said groundwater to the sanitary sewer.

Tom

Oh yeah, the sheet steel cover on that pit is hardly sealed. That is enough to flunk it as a sewage ejector.

[Jim Katen]

I originally used that wording, but revised it to lift pump because it is handling grey water from the laundry (and DW) and not solid waste. It's pretty common around here for a basement laundry to have an enclosed float actuated lift pump under the utility tub. What ever you call it, it should have backflow and shut off valves in it. Besides, it has to be a voilation of something more than common sense to dump contaminated water into groundwater before pumping said groundwater to the sanitary sewer.

Tom

Oh yeah, the sheet steel cover on that pit is hardly sealed. That is enough to flunk it as a sewage ejector.

All good points.

How about if they were to enlarge and deepen the pit, install a solid poly sump liner, connect backwater valves to the groundwater inlet lines and then configure the whole thing as a sewage ejector? You then have a basic sewage ejector that also handled some ground water. The ground water might add a slight burden to the public sewage treatment plant, but what's a little ground water between friends?

The alternative is to install a sewage ejector that just handled the washer discharge and upgrade the existing sump pump to discharge into the storm sewer.

- Jim Katen, Oregon

[Tom Raymond]

OK, so we've determined there are at lesat a half a dozen ways to correct the sump/lift/ejector pump. I was more concerned with the pipe on the left that is connected to the sanitary sewer and is open in the sump pit and at the top of the tee. I can't imagine what they were thinking there.

Tom

[Jim Katen]

OK, so we've determined there are at lesat a half a dozen ways to correct the sump/lift/ejector pump. I was more concerned with the pipe on the left that is connected to the sanitary sewer and is open in the sump pit and at the top of the tee. I can't imagine what they were thinking there.

Tom

Me neither. Though I suspect that it might have been their first attempt at a discharge line. It makes no sense as it is now.

As for your other question about the sump pump discharing into a sanitary sewer, I'm not sure there's a rule against it -- at least not in the IRC. The closest reference I can find is at 405.2.3

R405.2.3 Drainage system. In other than Group I soils, a sump shall be provided to drain the porous layer and footings. The sump shall be at least 24 inches (610 mm) in diameter or 20 inches square (0.0129 m2), shall extend at least 24 inches (610 mm) below the bottom of the basement floor and shall be capable of positive gravity or mechanical drainage to remove any accumulated water. The drainage system shall discharge into an approved sewer system or to daylight.

I suspect that the definition for an "approved sewer system" varies from one place to another.

- Jim Katen, Oregon

[SWagar]

My guess is that the person responsible for the "fix" watched episode 1 "Plumbing Your House" on HGTV. He knew he needed a vent ... but didn't know it needed to go outside. I bet he did not watch episode number 2. Besides it works don't it ?!?

In the first pic what is the left vertical pipe connected to, the horizontal pipe behind it? Does water flow uphill to get to the vertical drain?

Very interesting .....

[Tom Raymond]

The horizontal pipe is the drain for the kitchen sink that is off to the left of the picture, it continues to the right, where it turns 90 degrees toward the viewer, just off the picture again. About 10' from there it connects to the main stack. The left vertical pipe is only connected to the horizontal drain pipe. It is open at the tee, and in the sump pit. Even if it was supposed to be the sump drain it be spraying the ceiling.

I just noticed looking at the pictures again, the horizontal sanitary tee is even installed backwards. I guess I'll have to chalk it up to another case of "shouldn't do it yourself". I already told them to rip it out and cap the holes in the drain pipe.

Tom

[Brandon Chew]

As for your other question about the sump pump discharing into a sanitary sewer, I'm not sure there's a rule against it -- at least not in the IRC.

You'll usually find these prohibitions in the local sewer use law. The building code will usually just say something like "discharge to an approved location"; then the sewer use law will prohibit things like roof drains, a/c condensate, and sump pumps from being discharged into the sanitary sewer system.