Thoughts on backyard drainage (long, but best to read it all)

In My Humble Opinion
1

We’re in a large subdivision, on a street of detached houses. Our backyard is always a bit soggy - drainage isn’t great, heavy rains leave parts of it fairly swampy, and we finally found out, last year, just where our sump pump outflow goes: it goes into an underground pipe, that simply stops underground about 10 feet away from the house.

We also have an outside stairway, with a drain in the bottom that drains into the sump. It can get clogged with leaves, which allows the stairway to fill (once, judging by leaf litter, it was a foot or more deep). Needless to say, this causes problems. We thought it was taken care of by having a better leaf barrier, but this Saturday even that was overwhelmed by the torrential rains - the back yard was just too soaked and apparently water was coming in over the top of the stairwell. Fortunately, we were on the lookout and kept the worst of it out by clearing the drain (outside) and heavy use of the shop vac inside. The carpet got slightly damp but just within a couple inches of the linoleum we have just inside the door.

We had an expert come out last year who suggested that the permanent solution to the drain issue is to jackhammer a much larger drain, put a separate sump pump just inside that door, that would go up through the wall and out the side of the house, then run a drain underground toward the front, to soak into the front lawn and eventually make its way to the storm drain. The existing sump would remain (it’s on the other side of the door), but they would run a different drain line around the other side of the house, and run THAT toward the front as well. One issue with the second sump: if power goes out. We put a water-backup sump on the main house sump pump, but if power goes out, this new one wouldn’t have that, and there’s no good way to put one in there without being hideous (it would be in the finished living area).

Our next door neigbors - on both sides - have their sump output running underground and through the curb (there are pipe outlets in the curb), but supposedly that’s no longer up to code. I have a call in to the county to verify that.

We will have the gutters checked and cleaned out - that might have contributed to the spillage. Another suggestion we’ve had is to put an awning or roof extension over the stairwell - that might be prohibitively expensive and/or prohibited by the HOA (awnings are permitted but most be retractable and it’s more targeted at covering porches, for example).

Having the sump output routed to the front seems needed regardless - I’m wondering if there are some landscaping tricks we can implement to take advantage of the drainage. I’m concerned that having the water outlet to the front will just move the problem; if we had plantings there, perhaps, maybe that would suck up some of the excess water. One issue though is that it’s in a fairly narrow strip of land (less than 20 feet, maybe less than 15) between our driveway and the neighbor’s.

Thoughts? suggestions?

2

In my community discharging a sump pump into the storm sewer is illegal; it has to be discharged into the landscaping.

Our sump pump was installed to discharged through a 3" pipe buried about six inches underground. There was a 90-degree elbow which brought the pipe up to a slotted cap level in the lawn. It worked fine as long in the summer, but in the (Minnesota) winter of course it froze at the elbow, which caused the pipe to backup to point where it pipe was attached to the house. Disaster!

The fix was to extend the pipe another 20 feet and have it end at the end of a slight slope, so it was draining to “sunlight”. That let gravity drain the pipe so it would never freeze. If your landscaping allows, between the houses, might be the simplest solution.

Also consider if your gutters are correctly sized and positioned.

3

Dealing with water run-off is tough, and there is no one perfect solution. You have to consider all of the variables, and attack a number of them. Even then, you may run into issues.

One huge issue is to check your overall grading to ensure that as much water as possible flows away from the house. Make sure your downspouts go far from the house, either with above surface extenders or to a buried french drain. Of course, you cannot direct the water off of your property to cause problems for your neighbors. You might want to check to make sure no neighbors are adding their water to your problem.

Sumps are always problematic - as you mention, what to do if the power goes out. You can install a battery back-up, but those have limited battery life. The best solution I’ve heard of is a gas generator - which is pricey.

But your sump really shouldn’t have to be working so hard, so long as your property is graded properly. If not, you’re likely pumping the water out only to have it make its way back to your foundation tile.

You can redirect a ton of water with berms and swales. And yeah, keep those drains and gutters clear.

No single, cheap solution. We had water issues in our last 2 houses. This time around, we were determined to buy a house that was on a relatively high lot, and situated on the lot so as to drain. IME, that is the only real solution.

4

What’s the soil type?

If you can’t discharge into a sewer/storm drain, can you drill a hole and get to a more absorbent strata?

If you have nothing but clay, anything below might help. If it is sand all the way down, you are probably already pumping as much as it can take.

5

It’s pretty clay-ey here. I doubt we could drill deep enough to find a better outflow for the water - small lots, lots of buried utilities, and an HOA would all make that tough :slight_smile:

If we were to run the pipe to the front yard, that would definitely be better as that slopes gently downward toward the street. Of course, at least some of that water would then wind up in the storm drain at some point, as it trickles down the lawn.

We’re still waiting to hear back from the county about what we can do with the runoff. I hope they don’t make the neighbors stop their draining into the curb - that would just worsen everyone’s problem. I do know we’re not supposed to put the sump outflow into the sewer.

The neighboors are probably not contributing much - there’s a slight “vee” between the properties, so any water running from one property should generally go into that versus into the other’s yard. Plus of course their sumps all go into pipes that go into the street.

I’m sure that’s a big part of what’s happening. With a gully-washer like we had the other day, I would bet even a better graded lawn sump outflow would have been overwhelmed, but in the normal course of things it shouldn’t be as much of a problem.

For what it’s worth, the water-powered backup should handle most sump issues - we’ve never lost power AND water at the same time.

6

I overlooked the bit about having a HOA - are they aware of your problem(s)? Do a large number of other lots have the same issues?

Are there well-drillers in the area? They could tell you if they had run into something better than clay when poking around the area.

7

Depending on how far down you hit something besides clay, you might consider a dry well. How fast does your yard fill up? Would water be replaced from the neighbors’ yards? Do you want to pay electricity to run an added sump pump?

8

I don’t see why a HOA would object to a dry well. I’d go big, make it say 8’ long, 4’ wide and 4’ deep. Dig the hole, build walls inside of masonry blocks, run the pipe in gaps between the blocks, put concrete slabs over the hole, backfill with peastone, then bury it. Plus I’d get a separate pump for your doorway area.

9

One more thing, interview several different contractors asking what they would do. Gutter people, plumbers, permaseal, landscapers… Unfortunately, too often a contractor will say what you need is what they are selling. You might need a combination of several approaches rather than a single solution.

And ask your neighbors. Unless yours is the only house sitting in the bottom of the bowl, it is likely others had similar experiences.

Plants can help soak up water, but it doesn’t sound like you have enough room to plant a willow. Anything less will (IMO) only help with a fraction of the problem. But, yeah, it would be better to have thirsty shrubs than bare lawn. A lot of native plants and grasses have huge root systems.

Good luck!

10

Two of our three neighbors’ yards drain into ours. We used to get pools of water for months into summer.

We had the back regraded, and drains running out into the front and a dry well. Dry as a bone ever since, and we have had a rainy spring.

Good luck.

Regards,
Shodan

11

The last house my parents bought while I was still under their roof turned out to have a backyard drainage problem. They had a cubic assload of dirt trucked in and regraded the yard themselves.

12

Bumping this very, very old thread as the topic has been on our minds lately (with Florence coming to visit this week).

We wound up getting a different contractor in for an estimate.

The first guy (mentioned upthread) told me that the concept of discharging water to the curb (as the neighbors were doing) was against county code due to concerns over generating ice dams on the street.

The second guy said “???” when told this. As did a county office I contacted. A nearby county has an illustration of the exact scenario on their web page, with a notation saying “that’s not ideal, but it’s an option if nothing else works”. Our street is privately maintained so the county doesn’t care anyway. And our HOA had no issues with the concept.

So we wound up:

  1. Having a much bigger (1 square foot, I think) box drain put into the stairway bottom
  2. which still connects to the sump pump
  3. which now has an outlet on the side of the house, vs the middle of the back of the house
  4. which drains into a pipe set into the ground
  5. which runs to the front of the house, through a new hole in the curb, and thence along the curb and into the nearby storm drain.

The former sump output - which was literally just into a pipe that terminated underground catty-corner from the house, hence the constant post-rain swampitude - was just left in place.

The day they installed the box drain was reasonably unpleasant, as it involved some jackhammering. I had an MRI that evening, which was a piece of cake noise-wise, as I was already partially deafened :D.

Most of the neighbors have had issues with the basement stairs flooding; several have installed larger drains as we did. Only the ones on this side of the street have had to go with the “drain through the curb” approach; the people on the other side have sufficient natural slope to let their outflow drain out into the woods behind their houses.

13

The takeaway from this, for anyone who might buy a house in the future, is ALWAYS consider the drainage before you buy.

If your lot has crappy drainage, it’s generally a difficult fix if it can be fixed at all. So ask where the water goes when it rains. Where’s the downhill, or failing that a storm drain, that will take the water away from your house, so that it doesn’t wind up in your basement for lack of a better place to go?

And of course your purchase should be contingent on a home inspection, and the drainage should be one of the things your home inspector looks at.

14

I totally agree!!

We bought during an insane sellers’ market (hence getting enough out of the old place to afford the new) - and I do wish that had been part of the inspection but even if it had and we’d disliked it, our options in this ZIP code were quite limited. There was literally one other house on the market (on the plus side, THAT place sat on a hill and would have had much better drainage, LOL).

15

Lemme guess, early to mid 2000s? Lord, things were crazy then - tough time to buy if you needed to be in the market right then. (Which you probably did, or you would have waited.) We were lucky to buy back in 1998 when the market was warming up, but hadn’t gotten crazy yet.

16

Yep - 2002. We’d bought our previous place, a townhouse, in 1989 - near the end of a bit of a run-up. It wasn’t until 1999 or so where we’d have been able to sell it for the same as we’d bought it for. We still figured we’d never sell for enough to get a bigger place, and spent $$ remodelling the kitchen… then the market went NUTS.

We closed on the new place a year after the kitchen remodel. Any sooner and we wouldn’t have had the down payment for the new, any later and we couldn’t have afforded the new.

17

Mama Zappa, you didn’t actually say whether the changes improved the situation. If you don’t mind my asking, is your backyard less swampy?

As a related question, are you in a climate where mosquitos are not an issue? I’m in the Washington DC area, and if I had standing water in my yard, it would be unlivable in the summer.

18

It is much less swampy - the reason it was so soggy in places was because the sump’s output just ended underground - at most 15 feed away from the house. That was probably permissible when the place was built but I doubt it would be up to code now. It can still get soggy after a heavy rain, but it’s just from the rain that fell on it - not all the rain that fell anywhere around the house.

The basement hasn’t flooded since we had the bigger drain put in. The old drain was something like 6 inches in diameter and would frequently clog with leaves. Cleaning the gutters certainly helped the situation, as they’d overflow right into the stairwell.

And since the sump’s output now goes into a pipe that is open all the way to the street, there’s no longer an issue with soggy ground. I suspect the original sump output probably backed up sometimes since the tube just ended in dirt, not any kind of gravel field that let the water percolate away. And even if it didn’t back up, it would soak down into the ground and wind up right back in the sump. It was stunningly bad design, when we found out what had really been going on.

The yard would get very soggy, but never any visible standing water. While it probably wasn’t great from a mosquito standpoint, it could have been far worse. We’re DC metro as well, so yeah, skeeters would have been a problem.