Leaky laterals causing basement flooding?

[ray hampton]

they can put a liner inside of the bigger pipes if I not mistaker

[Tom Stenzel]

they can put a liner inside of the bigger pipes if I not mistaker

It's pretty common to line existing pipes when possible, the cost savings is too great to ignore. Lining the pipe reduces the cross section, but the lining companies claim that the improved Manning number (wall roughness) mitigates some of this.

Phil, there are other factors to consider. With the states and EPA cracking down on Combined Sewage Overflows, it's possible that some of the steps taken in the Milwaukee area outside of your suburb are affecting you. CSO retention basins may require higher levels or a surcharged interceptor to get the water into the facility. That would affect YOUR drainage. Leaky or not, laterals have to have someplace for the water to go.

In the Detroit area we've had concrete bulkheads that separate the sanitary and storm systems collapse and reconnect the two systems.

Your suburb may be mature but others that share the same interceptor(s) may have grown and increased the system loading.

I knew one of the instrumentation/controls techs at the Jones Island facility but lost touch with him about 15 years ago. He's probably retired by now. But he would have been a good person to ask if there were any problems with the collection system. Sorry.

-Tom Stenzel

[Glenn Vaughn]

Logicallt if the sewer and laterals are not interconnected and unless the sewer is brerached, np ampunt of leakafe from the laterals will affect flows in the sewer. If thet are interconnected, leaking laterals would actually relive some of the total flow in the system - much of the eater would be retained the ground and not rntering the sewer.


Undergroinf rivers do esist, we have one about 50 feet under our property. Most do not affect the surface (that is why they are called "underground").

One possibility is the the line from the jouse to the sewer is breached and heavy rains are saturating the soil enough to fill the line amd back-up into the house.

[Peter Stahl]

My sister-in-law had a back up in here sewer line and it came back out of her basement sink, no floor drains. Plumber put in a back flow preventer (check-valve) and she hasn't had a problem yet. I have a 10 year old house and it doesn't have a back flow preventer, I also don't have any drains in my basement either. Houses in my area don't have weeping system drains to the street either. All our storm water goes out to the river, none of it is connected to waste/sewer lines.

[Dave Wagner]

They do the smoke test here every couple years and make sure no one is hooked to the sewer system with their downspouts. All of our downspouts drain just away from the house, none are connected to any storm sewers or drains, just drain into the yard. Never had a problem with water in the basement.

We did have a small backup (my sewer line is about 4 feet up from the basement floor) when the clothes washer was running, couldn't figure it out, then it did it again a week or so later, so I had the sewer drain snaked,made it all way to the street and stopped, he couldn't get thru....did the camera and actually found a broken tile and falled about 1/2 way and would block the line for a while if something got caught.....we think it was when they put the new as line in and when they shoved the line underground it pushed a rock or something into the drain line.

Yes, I talked to the plumber and has seen new gas lines shoved right thru sewer lines and block them!

There are also check valves that can be installed in the sewer drain lines to prevent this.
http://www.backwater-valves.com/

[Phil Thien]

Phil, there are other factors to consider. With the states and EPA cracking down on Combined Sewage Overflows, it's possible that some of the steps taken in the Milwaukee area outside of your suburb are affecting you. CSO retention basins may require higher levels or a surcharged interceptor to get the water into the facility. That would affect YOUR drainage. Leaky or not, laterals have to have someplace for the water to go.

These issues have been touched on in the local newspaper a bit. Unfortunately, without knowing the precise locations of basins and pumps, it is difficult to know what impact they have for our village.

In July 2010, we had over seven inches of rain in just two hours. It was really quite unbelievable. I remember walking home with my dog from work (just three blocks) and seeing my wife leaving in the van to come get me. Luckily, I was able to scream and get her attention to return, because had she proceeded, she would have driven right into about 20" of water.

Given the amount of rain, it was surprising there wasn't more damage. Not saying people didn't get flooded, but 3-1/2" of rain per hour for two hours is worst-case scenario.

I remember reading in the newspaper (a couple days before that storm) that the MMSD (Milwaukee Metropolitan Sewage District) was preparing for particularly heavy rains by bringing in more pumps, and making sure all their ducks were in a row. I really have to give whomever there took their weather report so seriously a huge high-five for getting it right. So many times, we (specifically I) criticise bureaucracies for dropping the ball. July 2010, a bureaucracy got it right, took as many steps as possible to prepare, and mitigated much of the damage.

A lot of people in my village had water enter their basements because of incorrectly pitched patios or driveways, problematic window wells, etc.

Still others experienced water entering their basements via their lateral. What normally caries sewage to the main was now carrying water into their basements.

After the dust cleared, people accepted crazy things can happen in 7" rain storms. They made their insurance claims, cleaned-up, threw-out contaminated stuff, replaced carpeting, drywall, and panelling, etc.

A month or so later, another rain storm dropped something like an inch of 1-1/2" of rain, and those same people that experienced problems w/ their laterals flooding their basements went through it again. Many of them had just replaced/repainted, etc., and they were pretty upset. Understandably so.

Many of these people lived on these streets for decades, and never experienced a problem like this before. And they want answers.

Unfortunately, the village's consultant isn't coming up reasonable answers (IMHO). Come-on, leaky laterals? All of a sudden? All the sewer lines that have been replaced in the last few years are perfect, this is leaky laterals?

I'm only a little surprised that the village board and the employees are going along with it.

As someone that fixes computers for a living, I can tell you that the capacity for critical thinking is simply evaporating.

People will believe whatever they are told. Nobody is skeptical any more.

I will mention that they recently replaced the sewers up the block and had to cross the intersection which we can see from our window. The method they use is different from when I was a kid.

When I was a kid, they did the street in front of our house. They dug it all up for a mile. The dug down to the sewers. They replaced stuff, they backfilled, and then paved. We had an alley to get to the garage with the cars.

There are no alleys here. They dig down a bit at a time, replace some of the sewers, and then backfill. They move in little bits, a few houses every day. When they had to cross the intersection, they excavated the same spot at least six times. They repaved (with concrete) at least three times, two times it had to be cut-out and excavated again. Not sure if something was wrong, or if that was part of the plan.

But it doesn't give me a lot of confidence in their work.

[Brian Elfert]

It was fairly common to have combined sanitary and storm sewers. The problem with combined systems is the sewage treatment plants would usually be overwhelmed during a rain event and untreated sewage would flow out of the plants. The state and the EPA have been requiring cities to separate storm and sanitary sewers for years to reduce the issues with overwhelmed treatment plants. I believe separation started where I live as early as the 1970s. My grandparents had issues with sewage backing up into their basement every time it rained heavily. The city rebuilt all the roads in the 1980s and also replaced all of the sewer lines too. The sewage backups stopped once the storm and sanitary were separated.

The city I live in went around a few years back and inspected every home for illegal connections of downspouts and sump pumps to the sanitary sewer. Homeowners were reimbursed 50% of the cost (up to $250) to remedy any illegal connections to the sanitary sewer. The city was paying huge fines for sending excess water to the treatment plant when it rained.

Most of my neighbors have old clay sewer lines and we have no issues with sewer backups. My house replaced a condemned house. The original house had clay lines that required root removal regularly. My new house has a new PVC sewer line all the way to the main and no more tree root issues.

[Phil Thien]

It was fairly common to have combined sanitary and storm sewers. The problem with combined systems is the sewage treatment plants would usually be overwhelmed during a rain event and untreated sewage would flow out of the plants. The state and the EPA have been requiring cities to separate storm and sanitary sewers for years to reduce the issues with overwhelmed treatment plants.

Here in greater Milwaukee, they determined the cost of separating the sewers in combined areas and determined that the cost was too great. Instead, they went with the "deep tunnel." Just as it sounds, it is a very large, very deep tunnel.

The intention was to be able to college all the combined waste and rain water in this deep tunnel until they have a chance to treat it all like it is sewage.

Capacity is still obviously finite, and during heavy rains they still flush the thing (untreated waste and all) into the lake.

The subject has made the paper over and over and over as they seem to release more untreated waste water than necessary. Of course, they don't know how much rain (exactly) will fall and they have to make room for any rain which may arrive. Apparently, the consequences of the tunnel filling entirely are rather dire.

For something that isn't a 100% fix, it sure was expensive.

I believe the writing is on the wall. I think the EPA will eventually order that the sewers be separated at some ungodly cost. Talk about shovel ready, this would have been the perfect project to pitch to the federal government a couple of years ago.

It is a shame we spent so much money on the deep tunnel and still pump untreated waste into the lake.

It is a crime the way we treat lake Michigan.

[Brian Elfert]

Many cities have old water and sewer pipes that are starting to fail. Forced sewer separation might finally force replacements and upgrades of this infrastructure. Yes, it will be costly, but it has to be done at some point. I believe that today's technology will last far longer than some of the technology used 80 or 100 years ago.

There are ways to reline sewers to avoid complete replacement, but that doesn't help to separate storm and sanitary.

[Peter Stahl]

Here in greater Milwaukee, they determined the cost of separating the sewers in combined areas and determined that the cost was too great. Instead, they went with the "deep tunnel." Just as it sounds, it is a very large, very deep tunnel.

The intention was to be able to college all the combined waste and rain water in this deep tunnel until they have a chance to treat it all like it is sewage.

Capacity is still obviously finite, and during heavy rains they still flush the thing (untreated waste and all) into the lake.

The subject has made the paper over and over and over as they seem to release more untreated waste water than necessary. Of course, they don't know how much rain (exactly) will fall and they have to make room for any rain which may arrive. Apparently, the consequences of the tunnel filling entirely are rather dire.

For something that isn't a 100% fix, it sure was expensive.

I believe the writing is on the wall. I think the EPA will eventually order that the sewers be separated at some ungodly cost. Talk about shovel ready, this would have been the perfect project to pitch to the federal government a couple of years ago.

It is a shame we spent so much money on the deep tunnel and still pump untreated waste into the lake.

It is a crime the way we treat lake Michigan.

I could see the Indian with a tear in his eye (Keep America Beautiful) from a old commercial years ago while I was reading this.

[ray hampton]

How do Boston Big Dig compare to this ? was the Boston Dig for a subway or for the drain water ?

[Brian Elfert]

The Big Dig in Boston was actually for roads. It did include some public transportation too including a tunnel for buses. A number of subway/rail projects promised as part of the Big Dig have yet to be built.

[Steve Campbell]

Phil believe it or not the ground water level goes through long term ups and downs. If this were the case it my be that the leaky sewer services could be part of your problem. Also in a heavy rain you will get lots of infiltration around all manhole castings. I know of an area that had an old building torn down. They just cut off the sewer pipe and buried it. Then when ever it rained hard the rainwater would find it's way to the old cut off pipe. One other problem we have around here is also a problem with more water coming in to our lift pump stations. When it rains hard the pumps just can't keep up, and backs up into basements. As budgets get cut every year you can expect it will get worse before it gets better. I have been in the sewer and water industry for over 40 years and I can tell you there are many places for water to get in.

Good luck Steve

[Phil Thien]

Digging up an old thread for an update.

It seems the "leaking lateral" issue is sort of taking hold nationwide. Many communities are now talking about leaky laterals as a contributing factor to sewer backups, and discharges of untreated waste water to rivers and other bodies of water.

Whenever I see something sort of take a life of its own like this, I start to suspect someone with a profit motive pushing an agenda.

In our area (greater Milwaukee), there seems to be a wider focus on leaky laterals as a major contributor to an overwhelming of "the system," resulting in basement flooding, and untreated sewage releases into local rivers, and lake Michigan.

There was an article in the paper this morning saying that the local authority seeks no more releases of untreated sewage by 2035, and that they are relying heavily on green efforts (permeable surfaces for parking lots, driveways, and patios, as well as water-absorbing gardens, rain barrels, oh and fixing leaking laterals). The writer of the article said these efforts could reduce the load on the system more than the deep tunnel that we were sold on decades ago (said deep tunnel is easily overwhelmed by heavy rain).

ANYWAY, I wrote to the author and said I didn't understand how basement flooding could start within minutes to a couple of hours of heavy rain if the cause was leaky laterals, if the water had to percolate through 6-10 feet of ground to get to the leaks.

The author (who has written extensively on local sewer issues) wrote-back saying that he had been present during testing which uncovered leaky laterals, that leaky laterals are a real problem. And as further proof, he cited a story about one of the local treatment facilities that only treats waste from an area where the waste/storm sewers are completely separated, which found that fully a week after some recent heavy rains, they were treating 2x more volume than they'd expect for a dry day.

So I wrote him back, and sent him a table (here: http://www.agriinfo.in/?page=topic&superid=1&topicid=5) that shows just how slowly water percolates through soil. We have a lot of clay in the soil here in WI. So it would seem that water may percolate at a rate of approx. .5" per hour. 12" in a day.

It seems to me that treating 2x the expected volume a week after heavy rainfalls indicates that it DOES take quite a while for the rain water to hit the laterals. His point was an argument in my favor, I don't think he "got" that.

The next question (and I will get this data), is what kind of volumes was the treatment facility processing DURING the storm, and in the hours/days after? What does the graph look like?

I'm not saying the leaky laterals don't contribute to higher treatment costs. But I'm absolutely calling BS to the notion that they are a contributing factor to emergency releases of untreated wastewater to rivers and lakes, and to sewer backups in basements.

Far more likely: Combined sewers in some areas (parts of Milwaukee, especially areas with all pavement like parts of downtown, are on single waste/storm sewers). Repairing leaky laterals when you've got rainwater entering the storm sewer system in large parts of Milwaukee is akin to slapping lipstick on a pig! You HAVE to separate the systems in those areas. They say it is cost prohibitive. Had they started decades ago, instead of building a deep tunnel, we'd probably be nearly done.

Also, some of the newer sewer work done has undoubtedly been part of the problem. In our own community, engineers found at least one (and I think it was two) spots where the sanitary sewer was directly connected to the storm sewer by contractors working for the village. Those problems were immediately corrected, and it is my understanding that far fewer basements have flooded since those repairs, even during very heavy rainfalls.

So tomorrow I intend to contact the MMSD (Milwaukee Metropolitan Sewage District) and ask them for a report showing how much they are treating daily at the South Shore facility.

It is disappointing that the newspaper journalist seemed to act like a mouthpiece for the agency on which he reports. He only said "laterals leak." He didn't seem to have an answer on how quickly leaky laterals could contribute to overwhelming the system, and he sure didn't seem interested in finding out.

[George Bokros]

Another issue maybe that the growth of the area has resulted in more hard surface (roads, driveways, parking lots) that results in more run off into the storm sewers.
True example -

Within an half mile of me by sight the city allowed a small company to expand and with that expansion they built more parking lot for employees. This created more hard surface so more run off. The run off after going to a sediment pond runs down the creek that runs across my property. Almost immediately when the parking lot was paved this creek began to overflow into peoples lots from the additional water run off.

In this case what was good for the city, more jobs and more taxes collected, was bad for the residents. This is called progress.

George