Bottom Line, Basement Flooding Sucks
If you’ve read this site over the years you’ll notice there are many articles about basement flooding. Never did I think I’d be writing an article about my own flooded basement. It’s a bit embarrassing actually made more so by the fact that it’s been a real bear to figure it out. What I hope to convey to my readers is that basement flooding can be difficult to figure out no matter how seasoned you are.
The Beginning: First Flood
We moved into our house about 10 months ago. It was completely gutted and rehabbed and the basement was finished before we moved in. A basement bathroom was built and the floor was tiled. The rest of the basement was carpeted. There were two low spots that I believed to be floor drains however, they were carpeted over. Since we moved into the house in late winter we would soon find out how the house handled a good rain. Unfortunately we found out pretty quick. During a nasty downpour in early spring I got the dreaded “wet carpet in basement, It’s flooding Sean” text from my wife. So I rushed home to find the carpet soaked in both low spots. I cut the carpeting back to confirm what I suspected, two floor drains both backing up. I had easy access to the cleanout on the waste stack so I got my hands on a Rigid K-1500 and opened up the sewer. The water went down and all seemed well that is until the next heavy rain. Once again I was out and about, and my wife texted me “water in basement again, come home”. So run home I did with the rodder in tow. Once again I punched through the blockage and the water drained. Of course I broke out the wet/dry vacuum, dehumidifier, fans and portable heater to dry out the carpeting.
Because of the age of the house and the proximity of several large trees I suspected I had a tree root issue. There were several lingering issues that had to be addressed before the flooding could be resolved. I had an accessible cleanout that dropped straight down into the house sewer however, the fitting used was not a long sweep fitting so the only head I could use to unblock the line was a spade head. Had a long sweep fitting been used we could have gradually opened up the sewer with a tree root cutting head. Would it have fixed the problem for good? No, however it would have bought us some time.
Next Step Sewer Video Inspection
Because there was no plumbing cleanout in the yard we had two choices; run a sewer camera up the line from the street or attempt to put the camera in the cleanout from the house. Luckily the sewer camera head was able to make the turn and we were able to assess the problem. From what we found we had two serious issues:
One was that fact that we had a ton of tree roots and there was really no way to get to them unless we came in from the street
Two was that the storm sewer was criminally undersized. Even during a moderate rain the storm sewer would run almost full. Translation: Even if we cleared the tree roots out we would still back up anytime we had a downpour.
Solutions Options For Basement Flooding Stemming From City Sewer
The easiest and cheapest solution would be to install a sewer cleanout in the front yard giving you access to the drain line to rod or hydrojet for drain cleaning. After you install the cleanout you jet both ways and then video inspect the sewer to ensure there are no tree roots. You then maintain the line with Root X to keep any future tree roots under control. The only problem is you aren’t addressing the undersized city storm sewer, so I guess along with this option you say daily prayers that it only rains a little.
The next option and one that I would certainly recommend is to install a sewer cleanout in the yard as stated above
but I would also install a backwater valve right inside the foundation wall with easy access in the basement. With this solution you are addressing the tree roots and maintenance difficulties and you are installing the heavy duty check valve to make sure no storm water floods your basement in the case of a down pour. The backwater valve is made to slam shut if water is backing up from the city sewer.
The third and potentially most extensive and expensive option would be to install a forced main flood control system. The first option gives you access to the sewer for tree root maintenance and for a possible blockage but does nothing to stop the water in the case of a surcharged city sewer. The second option gives you ease of access for maintenance purposes and a heavy-duty backwater valve to stop any water from backing up into your house. However, what happens when the check valve engages for an extended period of time during a long downpour? You can’t use the plumbing in your house. If you flush a toilet the wastewater is hitting a closed check valve, if you try washing clothes, using a dishwasher, etc. you will back up at the lowest fixture in the house. If you have a basement shower with a gravity sewer it’s coming up at that fixture. A forced main sewer is the answer. Some call this a sewer lift station but it’s really not. Let me explain the system:
- An excavation is made at a predetermined location where your sewer exits the house. You try to take landscaping and tree location into consideration when digging.
- After exposing the sewer line and expanding the excavation to accommodate a concrete manhole the aforementioned manhole is notched or cored for the sewer piping and the manhole is lowered into place. Here’s where the magic happens. The sewer is repiped with a sanitary tee turned to 10 or 2 o’clock. (stay with me I’ll explain in a second) A backwater valve is installed on the outlet side of the tee, a fitting reduced to 2” is installed on the outlet side of the back water valve and that is connected in-line with a short piece of pipe where it leaves the manhole.
- We are just going to concentrate on the plumbing in the manhole for now. An ejector pump is installed at the bottom of the pit and it is piped with a check valve over to the reduced fitting on the outlet side of the backwater valve.
- Lets move outside the manhole. You install a cleanout outside the manhole and connect it to the small piece of pipe exiting the manhole.
- Now you backfill with new trench backfill that conforms with all local and state codes.
So how does it all work? You have the cleanout so you can maintain the sewer in case of a backup from outlet side of the cleanout to the street. You have an opening inside the manhole so you can rod, hydro jet or camera from the manhole into the house and you have a backwater check valve in case of a surcharged city sewer. But what happens if the city sewer backs up and you are also using shower, toilet, dishwasher, clothes washer or any other plumbing fixture with a waste outlet? You’ve got a wastewater Mexican standoff. Wastewater is trying to leave the property but the check valve is shut because of the surcharged sewer. Remember that open tee fitting I wrote about above? In this particular case that open fitting would allow the wastewater to pour out into the pit so there is no potential backup in the house. Once the water level is high enough he ejector pump would cycle forcing the water on the city side of the check valve hence the name “forced main.” Once the flood control system was installed we had no more issues with sewer backups of any kind.
You could install an overhead sewer however in my case our foundation sits 2ft above the ground not allowing for much depth to bury the sewer line. An overhead sewer also doesn’t address fixture usage in the house in case of a city sewer backup. I’ve gone over installation of overhead sewers in the past so I’m not going to write about it again here.
Time Passes Basement Floods Again: The Mystery Continues
Everything was fantastic for some time. No heart palpitations when it rained, no water. Then slowly water started to accumulate back at the now concrete covered floor drain. I started to see a pattern and it was after we used the shower. But every time I ran the shower to watch if water reached the low spot none would show up. This isn’t completely unusual because there are instances where showers leak only when a person is using them due to the base flexing because of the weight. But again it was ambiguous and difficult to trouble shoot.
And then we had series of torrential rain over the course of 48 hours. I was in my office and I heard my son call for me rather sheepishly “Dad” “Yeah buddy what do you need?” “Um its flooding” “Ok how bad?” “Pretty bad, I think you need to see it” I walked out the door to see a quickly spreading pool of water maybe 8ft by 10ft 2” deep in the center. Because the basement is daily living space and my office is also located there I immediately sprint up the stairs to get towels and fans and a shop vac to attempt to control the flood.
There were a couple good things to come out of this flood. One, I was determined to figure this out and two I could see water coming up through the tiles in the bathroom and running from the back of the bathroom to the low spot. This gave me a clue as to the source of the flooding. It had to be coming from the foundation. Because there were several cracks that were repaired in the basement I never thought there would be another but I went outside to look at the foundation and estimated were the water was coming from and after digging down about 6” I found a crack and a patch.
At least I had a place to start however, this still didn’t take away the nagging feeling I had about the leaking shower. Finally I pulled back the carpet and ran the shower for about 15 minutes, sure enough water began running inside the wall right back to our now infamous low spot.
Now we knew we had not one but two leaks that were independent of one another but the water from each ended up in the same place. When doing work at another person’s home it’s usually pretty fun to tear things apart however, when it’s your own house not so much but demolition had to be done.
First we tore out the drywall covering the foundation wall to reveal as expected a pretty sizable crack that was patched however the epoxy covering the crack began to peel. I brought in a foundation-sealing expert and after he removed all of the epoxy patching he determined that the sealant probably didn’t go all the way through the crack. We set up a time to do it right.
On to that pain in the butt shower. After taking off the base board trim I could see that floor was open underneath the shower and the base was built on 2x4s to raise it off the ground a bit. I could see the shower drain piped into the ground but I couldn’t see beyond that. I turned the shower on and within seconds water began backing up from around the shower drain piping and it began running under the shower base and along the wall. Although I wasn’t sure why it was backing up yet at least I knew for sure there was a leak.
The next step was to uncover the connection and luckily for me that wasn’t too difficult. After breaking up some of the concrete right outside the shower and digging a bit I found an old floor drain. The plumber that piped the shower drain, piped it into the old floor drain with epoxy. (Code approved? NOT!) Although that is pretty shoddy plumbing what’s worse is that the waste piping serving the floor drain wasn’t taking any water.
Excavation to Uncover the Waste Piping
I had to do quite a bit of excavation to finally uncover the waste line servicing the floor drain. Once excavated I cut out a section of piping to find that it was 100% blocked with 20 years of black sediment. This floor drain hadn’t been functional in decades. I ended up cutting out all of the 2” piping until it became 4”. I ran our garden hose into the line to make sure it was clear and I visually inspected it as well. I subsequently re-piped the shower correctly with PVC, tested it, back filled it with pea gravel and some spoils and cemented over. We brought in a contractor to do the drywall, tile, painting and carpentry.
Would I call this endeavor a success? I suppose, one that took me 9 months to truly figure out. The reason I wanted to share this story with you especially in such detail is because I wanted you to know how difficult it is at times to track down basement flooding issues. I think of myself as an expert in this area of plumbing and it was still very difficult to pin down. I literally had three separate water issues manifesting in the same spot for three separate reasons. I’m lucky I still have hair because I pulled out some of it while trying to figure it out. If you bring a plumbing or basement leak professional out to your home give them the time to go over all the possibilities because as you’ve read above there are quite a few of them.