Clear Pipes To See What Happening

As a new homeowner, he was excited to put in a new sink, toilet and washing machine in the basement. That turned into a longer journey of figuring out a multi-part flooding solution.

Below is his story: sharing what he knows now, but wishes he knew before. You can see where he started and where he went. It includes a solution we have never seen before: two clear plastic “window” areas in the new sewer set up in order to see what is happening with the water…

We appreciate he shared his story with The City Sponge so we can all learn. 😅

Started with a gurgle

Excited to be able to do laundry at home, the new place had space for new plumbing fixtures. Lots of people do that.

One rainy day, the toilet started gurgling. Something was happening.

Then water started coming up and out.

Trying to determine the source of the water led to different theories:

• Was too much water coming from the roof?

• Or it was the neighbor’s downspouts which were spilling over into the yard?

• Or was it the building “trap” was cemented over by previous owner?

He couldn’t determine exactly why, so he bought a device to plug the toilet, a few flood bags and some leak sensors …and moved on.

More water

A month later, the washing machine and sink started gushing water. He also had 3-4 inches of water approaching his boiler.

After consulting with contractors, he installed “backflow preventer valves” under both the sink and the washing machine. There a few options.

Common types of backflow preventer valves

He chose to use simple “flap” valves.

In retrospect, he wishes now he had installed these at the time when he was installing the fixtures during the basement renovation (vs after). “This should have been done to begin with but I don't know if this was just not considered…or the contractor didn't know. In his defense, I didn't know either.” (Now you YOU know.)

But the toilet - which is where the first problem started - was left alone because it would be a bigger job to get under/behind it (more on that later).

Sump pump and pit

Given water came from different places, it seemed like a good strategy to set up a sump-pump in a pit to capture any water that might come in. Again, a lot of people do this for overflow emergency situations.

In creating a sump-pump pit, they ended up cutting into the house fresh air vent as a “temporary measure” to give them more time to do the work of digging up the toilet piping. Sure enough, a week later, more water much more water came IN, including via the sump pit.

Water needs places to go

What he saw outside his building concerned him as well. The water had few places to go and was not only coming down the road but also from under the ground.

With new motivation, he decided to cut up the wall and cement around the toilet, and dig into ground to install the a THIRD backflow preventer. And since things were ripped up, he decided to keep digging, literally…(if things are open, might as well check all of it).

What you find when you start digging

Once the tile was removed, he saw water signs on the wall emanating from the street and sewer water.

During the digging, he examined the building sewer trap, he discovered a hole in it and replaced the whole trap. It’s hard to see flooding problems when they are buried.

He then did a video sewer line inspection, and plumber said the sewer lines had some trash in there but otherwise it was in good condition.

They also inspected the fresh air vent and found it was completely clogged by the previous owner (this can affect air pressure and drainage).

Clear pipes and a camera

After clearing the air vent, he wanted a way to see that water and air could mix well and not back up. So instead of burying pipes as before, he decided to install a clear PVC pipe to be able to see how things were going.

But even after all that…he decided that to be safe, it would be best to also install a FOURTH backflow valve - a larger valve for the whole building.

Why? Because he wanted a first line of defense between his place and the city sewers, and take some pressure of the smaller check valves installed under the fixtures inside which can have higher rates of failure.

After a lot of research, he went with this one:

Here is a short clip from his basement showing the valve doing its job on a rainy day:

The yellow flap stays down during normal operation but it comes up and closes if backflow heads towards the house.

According to the valve company web site:

• A backwater valve can be installed in the basement at the exit point from the home or building, or in the sewer lateral outside of the building. A building may be susceptible to sewage backups if the lowest drain is less than 24" above the nearest upstream manhole. 

• This type of check valve should NOT be confused with and DOES NOT REPLACE the “sewer trap” that prevents sewer gas from entering a building where it is installed.

So the new system has two clear areas where he can see how water is moving, and even a camera to see it if he is not home.

Outside too

In addition to all the work in the basement, it felt like it would be best divert water from the roof away from the basement in the back area. So they ended up connecting 4 rain barrels together which can hold 200+ gallons of runoff (to see a runoff calculator, go here). He also removed some pavers from the yard and repurposed part of it to be a more absorbent rain garden.

This is a good example of recognizing that flood solutions work best when combining green and grey infrastructure, implemented both inside and outside.

Inside + Outside checklist

1. Inside: install backflow flap valves on all fixtures in the basement.

2. Inside: dig up and replace building trap.

3. Inside: replace fresh air vent to the building with PVC to ensure not clogged.

4. Inside: install building backflow valve with clear top to see what's going on.

5. Outside: replace & clean strainers on downspouts, connect to 4 rain barrels.

6. Outside: remove non-permeable pavers to use absorbent soil.

Big lessons to share

1. “Largest mistake was skipping a house inspection… interest rates were rising and I wanted to be a more attractive buyer. We didnt know about it. That said, a housing inspection may not have uncovered this.“

2. Installing backflow preventing check valves between the HOUSE and MAIN SEWER CONNECTION and on all fixtures in the basement.

3. Divert runoff and tighten up the outside, sealing holes along building edge and diverting roof runoff water to 4 rain barrels out back.

Did he contact DEP since related to sewer?

He hesitated initially because he wasnt sure if the DEP would come and inspect his place and potentially fine him for things that were there from the previous owner, or for his solution. But after doing a lot of work, he did ask the DEP to come check things out. They came when flooding was gone and said the issue was “not present at time of investigation.”

Closing thoughts

Homeowners should ideally see the DEP as partners vs “sewer police.” My guess is the DEP wants homeowners to have solid solutions in place MORE than they want small fines, and for people to fix things before they become bigger problems. If fear of fines may get in the way of knowledge sharing, maybe it could be removed at least for the initial consult. This way homeowners can feel comfortable asking for and getting initial advice, and that might help everyone, including the DEP. Water connects us.

Some useful links

• Right To Know Flooding History Law: Home buyers and renters have a right to know about flooding history now. New laws were passed recently to protect buyers and renters from situations like this.

• Sewer Line Connection Insurance from DEP: If sewer connection work scares you, there is an optional added insurance policy offered by the DEP to address that type of work (the connection between your house and the sewer). It costs like $150 a year. Note: my own experience contacting the company behind it: American Water Resources is their customer service is not great, but maybe you will have more luck.

• Easy Guide on Valve Options from Louisiana State Univ (they get water!)

• Mainline Backflow Valves With Clear Top and video on how it works

• Jay R Smith Knife Gate Valves 

Find this useful? Please share us with neighbors, your tenant or block association.

Copy and paste below (…go ahead 😅)

Hi: wanted to share this useful community newsletter I found about flooding info in NYC and tips on how to solve for it. Called The City Sponge. www.thecitysponge.com 
It may not be flooding today, but now is a good time to make the plan and do the work to prevent it. Hope you find useful.