Leaky laterals causing basement flooding?

[Phil Thien]

I thought I'd ask here. This doesn't make sense to me, maybe I'm wrong in my assumptions.

I live in a suburb of Milwaukee.

The last few big rains (more than an inch or two in a short amount of time), basements of homes in some areas have flooded. Not mine, thank God.

The water comes in through the floor drain, I've read. The last couple of years, there have been some real downpours with several inches of rain in an hour or so. "Hundred-year rains," but we've had a cluster of them in a year or two. Yet, we have had very heavy rains previously. But basements didn't flood then.

ANYHOW... some basements are flooding and people are plenty upset. Some of these people have lived here for decades and never experienced water backing up into their basements.

The municipality hired consultants, and they seem fixated on "leaky laterals," or the main drain line from the home to the street. The consultants insist that leaky laterals allow rain water to infiltrate the storm sewer system, which causes sewer backups into homes.

What I don't understand is how the problem can occur so quickly after the heavy rain starts. These leaky laterals are ten feet or more under ground.

It seems to me that it would take rain water some time to work 10' down into the soil, find the pipe, and make it into the system. Also, a lateral isn't going to collect water from THAT wide an area, THAT quickly, is it? Basements start flooding within just a few minutes of the very heavy rains starting, I believe.

I also don't understand why, when we have had very heavy rains previously, we didn't have this level of flooding. When we first moved-in 16+ years ago, there were some very heavy rains, and spotty basement flooding. But, to the best of my knowledge, the water came in from outside the home, not from the floor drains.

The consultants and the village make it seems like we have rivers running underground near the laterals. But, if that were the case, I'd expect to see sink holes resulting from erosion. And I'd expect the department of public works to be complaining of lots of soil in the sewers.

The suspicious side of me thinks there is a chance that some of the extensive sewer work in the last ten years may have been done improperly. Perhaps some pipes were undersized. Perhaps some pipes were improperly combined. Perhaps some joints were poorly fitted.

The village wants to inspect all the laterals and force anyone with any cracks to replace or line the lateral. At great expense. That suspicious side of me thinks the consultant wants to line the pockets of contractor friends.

I'm concerned that all this work will be done and basements will still flood.

I do know that simply installing a backflow preventer would stop the backing-up problem. Many houses have valves already. It seems making nearly everyone with the old clay tiles cough-up $6k is a great way to line the pockets of contractors when adding a backflor preventor is less expensive and a guaranteed fix (compared to fixing laterals).

Any thoughts?

Anyone go through anything like this in your own neck of the woods?

[JohnT Fitzgerald]

Phil, I am by no means trained or experienced on this topic - but I did read an article a while ago about how sinkholes are formed. If there are "leaky laterals" then water would not be the only thing making it's way into and down the pipes - also surrounding sediment and soil. This could gradually open up easier channels for surface water to make it down to the pipes. You might think it's 10' of solid ground, but it just might not be.

[Dan Hintz]

Ignore the man behind the curtain!




Someone is floating smoke to hide the fact that they don't yet know the cause... leaky laterals, as you said, could not only never flood that fast without a direct route to the water, and think of how much water would have to literally stuff them before the main couldn't handle it and it backed up into the smaller drains. It no make sense, Dr. Jones!

[Lee Schierer]

Most likely the cause is outdated or clogged storm sewers that were not designed for the amount of water they are now handling. It is a common occurrence now that northern climates area getting more severe rain showers. Older homes were typically connected directly to storm sewers without benefit of back flow prevention valves. They are pretty cheap insurance if installed when the home was constructed, but are more costly now that all the landscaping is done since you have to dig and possibly break up the floor in the house.

[Phil Thien]

Ignore the man behind the curtain!

Someone is floating smoke to hide the fact that they don't yet know the cause... leaky laterals, as you said, could not only never flood that fast without a direct route to the water, and think of how much water would have to literally stuff them before the main couldn't handle it and it backed up into the smaller drains. It no make sense, Dr. Jones!

The "consultant" recently said every single lateral needs to be inspected (at a cost), and any any sort of problems identified need to be fixed (fixing can run about $6000 per).

So the village hired the consultant to inspect every lateral (at a cost, of course).

That seems best-case for the consultant. That is a lot of work, resulting in a lot of income.

I cannot discount the possibility that the consultant is best friends with all the areas contractors that perform lateral repairs, either. You like to think the best of people, but so often you discover the worst.

I also cannot discount the chance that village hall is pressing the consultant in this direction because they want to conceal the true problem (for instance, sewer work that was performed incorrectly and was possible known of by people at village hall).

The fact is, the village right to our south has COMBINED sanitary and rain lines. So it seems possible, to me, that if there is very heavy rain, they could saturate their lines in little time. I am not familiar with how sewer lines are handled where one community ends and another begins. I suppose the systems could be entirely separate. Somehow, though, I suspect that isn't always the case.

So I thought I'd ask here before I become more involved by attending meetings and communicating (with village hall and my neighbors) my concerns about the direction of the work.

[Phil Thien]

Most likely the cause is outdated or clogged storm sewers that were not designed for the amount of water they are now handling. It is a common occurrence now that northern climates area getting more severe rain showers. Older homes were typically connected directly to storm sewers without benefit of back flow prevention valves. They are pretty cheap insurance if installed when the home was constructed, but are more costly now that all the landscaping is done since you have to dig and possibly break up the floor in the house.

To my way of thinking, no amount of rain should cause a sanitary backup in your basement unless there is water infiltration from somewhere.

The first thought this consultant had was that people had weeping and gutter systems illegally connected to sanitary systems.

And they found some. Some houses apparently have gutters feeding the sanitary sewers. And that still has not been fully corrected. Perhaps I have been too lax in not attending the meetings. But it seems to me that once you have identified several people pouring that much water into the sanitary system, you don't go any further until that is corrected.

Apparently some people are arguing that they cannot disconnect the rain water from their sanitary easily. And, that their houses are 75 years old, their downspouts always emptied into sanitary lines, and there was never before a problem.

The "never before a problem" doesn't fall on deaf ears for me. I'm very open to that argument. These homeowners are saying "look elsewhere, my configuration hasn't changed in 75 years." Now, I suppose it is possible that sanitary sewer lines were replaced with smaller ones that can no longer handle that load. And I suppose the people that called for smaller lines may not have been aware of some older homes pouring that much water into the sanitary lines. And if that is the case, those houses should be forced to disconnect, or be responsible for any damage. OTOH, if sewers have been replaced and the sizes have not changed, then the problem is elsewhere (if there was no problem with a 2" rainfall ten years ago, and there is one today, the problem MUST be elsewhere).

It just seems to me that you go after the largest contributors of rain water first.

It wouldn't seem to be leaky laterals to me.

I still believe something is configured incorrectly, or newer pipes are smaller than older pipes and we have to make adjustments.

I'm on the edge of the village, and I'm on the largest street. The sewer deep under our street is called the Hampton Express. I don't know the size, but it is apparently BIG (when they name a sewer line, it is probably pretty big) and feeds directly into the "deep tunnel" (another boondoggle). I'm pretty sure I could empty an Olympic pool into a 6" line during the heaviest rain storm w/o causing any problems.

But I am concerned that some joker is going to say I need to fix this, or fix that, just to line the pockets of his contractor friends. So I'm trying to get in front of this.

[Ken Fitzgerald]

Phil,
If the storm water and the sewer system are interconnected and the problem only happens when it storms, I would suggest that Lee is correct.

The number of homes being serviced by the existing system has outgrown the carrying capacity of the system or it's damaged and not handling the increased amount of water during the storms.

It would be very reasonable to think that as a suburb grew, more homes were added to the existing sewer systems and more street drains to handle the water in these same areas. All it would take would be one miscalculation or failure to take this into consideration and all future calculations would be in error too as the community continues to grow.

Adding the back flow preventer would protect ones home but it makes the problem worse for the guy who doesn't have one as the relief for the water has one less outlet.

[Lee Schierer]

Many older cities used storm sewers and sanitary as the same system and it is common for heavy rainfall to cause problems. That used to be the case in a couple of city/towns near me. People connected their basement drains to the sewer system and then connected their downspouts into their weeping system. Eventually they overwhelm the street drains and people end up with water in their basements coming up the floor drains during extra heavy rain periods. The only way to protect homes is to install back flow preventers in the connection to the sewers and not have downspouts connected to sanitary systems. Our local municipalities put smoke generators on the sanitary systems and then observed where smoke was coming out of downspouts. Illegal connections were then identified and given a fixed time limit to fix the problem before fines were levied. The fact that a home is 75+ years old had no bearing on the problem, some homes were over 100 years old.

[ray hampton]

To my way of thinking, no amount of rain should cause a sanitary backup in your basement unless there is water infiltration from somewhere.

The first thought this consultant had was that people had weeping and gutter systems illegally connected to sanitary systems.

And they found some. Some houses apparently have gutters feeding the sanitary sewers. And that still has not been fully corrected. Perhaps I have been too lax in not attending the meetings. But it seems to me that once you have identified several people pouring that much water into the sanitary system, you don't go any further until that is corrected.

Apparently some people are arguing that they cannot disconnect the rain water from their sanitary easily. And, that their houses are 75 years old, their downspouts always emptied into sanitary lines, and there was never before a problem.

The "never before a problem" doesn't fall on deaf ears for me. I'm very open to that argument. These homeowners are saying "look elsewhere, my configuration hasn't changed in 75 years." Now, I suppose it is possible that sanitary sewer lines were replaced with smaller ones that can no longer handle that load. And I suppose the people that called for smaller lines may not have been aware of some older homes pouring that much water into the sanitary lines. And if that is the case, those houses should be forced to disconnect, or be responsible for any damage. OTOH, if sewers have been replaced and the sizes have not changed, then the problem is elsewhere (if there was no problem with a 2" rainfall ten years ago, and there is one today, the problem MUST be elsewhere).

It just seems to me that you go after the largest contributors of rain water first.

It wouldn't seem to be leaky laterals to me.

I still believe something is configured incorrectly, or newer pipes are smaller than older pipes and we have to make adjustments.

I'm on the edge of the village, and I'm on the largest street. The sewer deep under our street is called the Hampton Express. I don't know the size, but it is apparently BIG (when they name a sewer line, it is probably pretty big) and feeds directly into the "deep tunnel" (another boondoggle). I'm pretty sure I could empty an Olympic pool into a 6" line during the heaviest rain storm w/o causing any problems.

But I am concerned that some joker is going to say I need to fix this, or fix that, just to line the pockets of his contractor friends. So I'm trying to get in front of this.

I vote for a stop up pipe or partly blockage
what is the deal with the "Hampton Express ?
I saw water backup shoot 20 feet high out of a flood drain and all punch presses and other machines got shut-down and everybody got to work at pushing the water back into the drain

[Phil Thien]

Many older cities used storm sewers and sanitary as the same system and it is common for heavy rainfall to cause problems. That used to be the case in a couple of city/towns near me. People connected their basement drains to the sewer system and then connected their downspouts into their weeping system. Eventually they overwhelm the street drains and people end up with water in their basements coming up the floor drains during extra heavy rain periods. The only way to protect homes is to install back flow preventers in the connection to the sewers and not have downspouts connected to sanitary systems. Our local municipalities put smoke generators on the sanitary systems and then observed where smoke was coming out of downspouts. Illegal connections were then identified and given a fixed time limit to fix the problem before fines were levied. The fact that a home is 75+ years old had no bearing on the problem, some homes were over 100 years old.

I agree that the age of the home has no bearing.

And I agree with the steps you've outlined.

The village has done the smoke tests. They've identified houses w/ illegal connections. Most people have apparently corrected those issues, a few are fighting it I believe (on the basis that it has always been like that and never was a problem, and their particular reconfigurations are going to be very costly).

The village has gone from having few (if any) backups just ten years ago to having backups (in some cases) with less than an inch of rain (if it comes fast enough). It is always the same homes.

And the problems continue after the smoke tests and subsequent repairs.

So now the new consultant says "leaky laterals" and I'm calling you know what on that.

It seems, in the world of "likely scenarios," that this consultant has focused or what I think is a particularly unlikely one.

The odds of this being caused by a bunch of laterals that have all become very leaky in the last five or so years don't seem that great to me. Especially compared to the chances of one or more serious engineering or construction mistakes being made during all the sewer work they've done over the same time period.

The more I think about it, the more I'm thinking we need to find a new consultant that is perhaps better skilled at critical thinking and problem solving.

If you just changed the oil in your car and notice the next day it is a quart low, you don't start thinking your engine is burning oil fast. You check for a tight filter and drain plug, right?

[Phil Thien]

Phil,
If the storm water and the sewer system are interconnected and the problem only happens when it storms, I would suggest that Lee is correct.

The number of homes being serviced by the existing system has outgrown the carrying capacity of the system or it's damaged and not handling the increased amount of water during the storms.

It would be very reasonable to think that as a suburb grew, more homes were added to the existing sewer systems and more street drains to handle the water in these same areas. All it would take would be one miscalculation or failure to take this into consideration and all future calculations would be in error too as the community continues to grow.

Adding the back flow preventer would protect ones home but it makes the problem worse for the guy who doesn't have one as the relief for the water has one less outlet.

Agree w/ everything you said.

The systems aren't supposed to be interconnected in OUR village. But of course, if they are interconnected in an adjoining village, how isolated are they for us, right? Perhaps they are completely separate, perhaps not. I do know one area experiencing problems is right on the line w/ the village w/ shared systems.

I can tell you that we are land-locked. No new construction for probably about forty years. This is an OLD suburb.

I agree, too, that adding backflow preventers may cause some homes without them to have gushers in their basements. LOL, that would suck.

I think about 75% of the problem is that the guys doing this work are all too young. Not enough experience.

[Phil Thien]

I vote for a stop up pipe or partly blockage
what is the deal with the "Hampton Express ?
I saw water backup shoot 20 feet high out of a flood drain and all punch presses and other machines got shut-down and everybody got to work at pushing the water back into the drain

The Hampton Express is BIG. I will try to find the size. I imagine it is a 24" or 36" sanitary sewer. It isn't clogging.

But one of the smaller mains could.

The village does a pretty good job inspecting them, though.

If I had to guess the problem, I'd guess that, during one or two of the construction projects, a confused team cross-connected one or more smaller storm lines to sanitary lines. Or removed large backflow preventers they didn't think were necessary, or for which they didn't have replacements that were compatible with the PVC they were using.

They have tested with dye. But they are assuming they know all the inlets for storm water. I imagine there are some they don't know about.

If it were me, I'd go back project by project, in chronological order, to before the problem surfaced. Examine each completed project with scrutiny. Find old engineering documents and compare what was there, to what is there now.

And if possible, I'd find some old timers that worked for the department of public works 15+ years ago and ask them if they'd like $20k to come back for fifteen days (all expenses paid) and just take a look at the problem. Maybe we'd have to fly them in from Arizona, Florida, or California. It would be worth it. When they were here, we didn't have these problems. Maybe they'd know why we're having them now.

[ray hampton]

Phil, I agree about hiring the old hands for a week or 2
are your town pipes made out of wood by any change ?
I do not recall the correct details but a town in Ohio had problems with their pipes, the gas pipes run thru. the plumbing pipes [ I hope that the gas pipe run thru. the sewage drain ]not the water main, running a gas pipe thru. a water pipe will heat the water

[Phil Thien]

Phil, I agree about hiring the old hands for a week or 2
are your town pipes made out of wood by any change ?
I do not recall the correct details but a town in Ohio had problems with their pipes, the gas pipes run thru. the plumbing pipes [ I hope that the gas pipe run thru. the sewage drain ]not the water main, running a gas pipe thru. a water pipe will heat the water

The new stuff is PVC, the old stuff they have been replacing is (I believe) concrete.

When they replace the mains in the streets, I do not notice them actually removing the old stuff. I'm not sure if they break it up and leave it in the ground, or if they run the new pipes inside the old, or what. I'm afraid I have not paid close enough attention.

[Dan Hintz]

Filling of the laterals is easy enough to check, and it doesn't require a $6000/per issue with the board, either. Hang a cup a few inches from the ceiling of any laterals in question and wait for a rain. If the cup is filled, the lateral is getting overwhelmed. I figure it'll cost you about $3 in dixie cups and $5 in wire hangers from the local drycleaners. It's not high-falutin', but it'll sure do the job as well as any inspection. No point spending thousands of man hours looking for cracks/blockages if the tubes just aren't getting filled.

[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

[Jeremy Hamaker]

Phil, if it were me, I'd be thinking the same thing you are. This doesn't add up. Based on that I would think you have two options: Get involved and start raising these questions publicly or just wait and hope it all works out.
Of course, even if you do start raising the questions, I think a lot of people have a lot of money at stake here in contracting and repair work they could get, so it would be a fight even if you're right.
It's easy to say this since it's not my money, but if I did have the money, I'd consider hiring an attorney right now and getting prepped for a big lawsuit against the city. I'm the kind of cynic that thinks you and your neighbors are being lined up right now to get shafted. I hope I'm wrong about that... Good Luck either way, Sir!

[Brian Elfert]

Many of the older lines from houses to the sewer will leak especially the clay lines. If there are trees the roots will get into the joints in the clay pipe. I bought an old house and found old invoices for having roots cleared from the sewer line. I tore that house down and built a new one. The old sewer line was replaced with PVC pipe all the way to the sewer main. The guys doing the work said the PVC pipe wouldn't have root problems like the clay pipe and no problems yet after 11 years.

Edit: The lines for my old house were transite, not clay. Same issue with the joints and tree roots.

[Phil Thien]

I contacted the MMSD (Milwaukee Metropolitan Sewage District) and asked to speak to someone that could provide me with the daily volume of that South Shore plant. They put me into the voicemail of a publicist. We will see if I get a call back.

My prediction is I won't get the data I want, but I will get a complimentary lateral inspection. :)

[Matt Meiser]

"Complimentary Lateral Inspection" Is that a euphemism?

[Jim Koepke]

My prediction is I won't get the data I want, but I will get a complimentary lateral inspection.

The squeaky wheels will get greased for free. Those who do not speak up will find a bill in the mail for the work that may not be done.

jtk

[Dan Hintz]

"Complimentary Lateral Inspection" Is that a euphemism?

LOL, I thought the same thing...

[Matt Meiser]

If you have trouble getting the information you want, you might try the state. Exactly what you want typically had to go to the state each month here in Michigan. In Michigan its the Department of Environmental Quality but you'll have to research who to contact. Its also possible that some operational data might not be published for security reasons. I can't imagine why sewage treatment flow rates might be a security concern, but I'm not a security expert. There was a big security push at public utilities after 9/11.

[Phil Thien]

Thanks Matt, that is a great idea.

[Phil Thien]

Victory!!!

I thought I'd post a quick update. Full story here:

http://whitefishbay.patch.com/groups/politics-and-elections/p/private-lateral-project-killed-by-village-board

Basically, the entire project got canned.

And we (me and all of you, I don't think there was a single dissenter above) were correct when we said NO WAY was this a large contributor to flooding. I especially like this passage from the story:


Siegel said she was particularly swayed by Cumberland Boulevard resident Jon Isaacson, who said the board should be pursuing larger sources of inflow, such as disconnecting downspouts and foundation drains from the sanitary sewer system. A geological engineer by trade, Isaacson argued that leaky laterals have a relatively small impact on basement backups, because of the amount of time it takes for rain water to reach the underground laterals.

"By the time the inflow starts, the storm's over," he said. "...You (the board) are going with an extraordinary amount of money after a very small amount of water that's going to come after the storm."

I would like to state that I had not gone to any meetings or anything. But Whitefish Bay residents are upper-income, and tend to be highly educated (I live in what are called the cheap seats, the most expensive home in the village is worth about 7x mine, and the average is 2x mine).

I DID write the local newspaper and express my concerns (those above) to the reporter that covers these issues. He was 100% dismissive. I then forwarded an additional response to the editor and reporter, and never heard back from ANYONE. So you can guess where I'm forwarding this now!

ANYHOW...

The story really isn't over, IMHO. The question is, how did this happen to begin with? How were village trustees and managers convinced this was an intelligent path? I mean, if we (me and all of you) could so easily identify this as a worthless endeavor, then how did the trustees and village employees become convinced to take this path?

THAT is the question.

[Brian Elfert]

Our city went through and replaced water meters around 2008. They also did inspections of sump pumps to make sure they didn't pump into the sewer system. The city was going to be fined if they didn't reduce flow into the sewer system after a rain event.

I have huge amounts of water flowing into my sump pit so I actually had the city engineer out a few times to figure out what to do with the volume of water. The city engineer gave me unofficial approval to dump water into a drainage ditch behind my house. I asked for written approval which he said he can't give because legally no water can drain off your property. I ended up having to hire an engineering firm to make sure I could pump water that far as it is 200 feet from the sump pit. I had to bury a 2" line in the backyard and upgrade my sump pump to a larger one.

[John Pratt]

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.

+1 on the back flow preventer. In my younger days in Iowa (where we had basements) this was an issue. After we installed a back flow preventer (not very expensive), we were the only house on the block that no longer experienced the problems, until everyone started to catch on and got one for themselves.

[Steven Green]

I'm an old midwest farm boy and I can say for sure that a field lateral drains 10' on each side. The water will percolate down and the bulk will be gone in three or four days depending on the saturation of the earth and the amount of standing water in that area. Leaky laterals sound like a line of ... if you know what I mean. Unless you have a really high water table locally and the percolation rate is faster than a speeding bullet I think the city needs to get off the dime and figure out the bottlenecks and possibly add capacity if there has been some growth or a lot of second and third baths installed.
There are a number of municipalities that have campaigns every year to get downspouts removed from the sanitary system that are prexisting on homes that have grandfather status. I know the plants don't need a flood of runoff coming in each time it rains, but, I also don't believe sanitary lines and storm water lines should be connected.

[Phil Thien]

I'm an old midwest farm boy and I can say for sure that a field lateral drains 10' on each side. The water will percolate down and the bulk will be gone in three or four days depending on the saturation of the earth and the amount of standing water in that area. Leaky laterals sound like a line of ... if you know what I mean. Unless you have a really high water table locally and the percolation rate is faster than a speeding bullet I think the city needs to get off the dime and figure out the bottlenecks and possibly add capacity if there has been some growth or a lot of second and third baths installed.
There are a number of municipalities that have campaigns every year to get downspouts removed from the sanitary system that are prexisting on homes that have grandfather status. I know the plants don't need a flood of runoff coming in each time it rains, but, I also don't believe sanitary lines and storm water lines should be connected.

As it turns out...

We have this giant deep tunnel here in Milwaukee. Huge project, designed to capture combined sewage/rain water from locations where the systems are not separated, during major storms.

The tunnel was pitched as a less-expensive alternative to splitting the systems in the oldest parts of the city (and one suburb, I believe). It (tunnel) was supposed to reduce the need for dumping untreated sewage into Lake Michigan from a every-time-it-rains-hard occurrence to something that would happen only every few years, in the very heaviest of rains.

It turns out that they (architects of the deep tunnel) probably way underestimated the amount of combined rain/sewage they'd collect, and probably didn't do that hot a job designing the pumping, because the # of untreated wastewater releases continued to be consistently high. One contributing factor was that the authority that ran the "system" started releasing untreated sewage rather early during even moderate rainfalls because they said they couldn't pump it out fast enough if the rain started coming faster.

It is akin to trying to empty a glass of soda with a straw when someone else is filling it from a soda fountain.

Politically, the release of untreated wastewater is highly unpopular. Billions (I believe) of dollars were spent on this tunnel, assurances were made, people were not happy with the thought that the tunnel would not fulfill the promises made.

So apparently a few years ago the authority that operates the deep tunnel and the treatment facilities reduced the rate at which they would ACCEPT waste INTO the system. Apparently some bottlenecks were created to reduce demand on the system, in hopes they'd be able to reduce the # of untreated releases. It didn't work.

What happened is that demand was not decreased enough to reduce releases, but it did create the problem of backups in some areas. Basically, MMSD (the authority) turned basements into untreated wastewater holding tanks, LOL.

In the meantime, there have been many street projects in our area, where the sewage and water lines are replaced, and the streets repaved. From my untrained eye, it appears they are replacing much older, much larger sewage pipes (concrete, I believe) with much smaller PVC pipes. So I think this has decrease capacity, and also increased velocity.

AND when all this work was done, there were mistakes made. There is at least one documented instance of a rainwater pipe being connected to a sewage pipe (woops). This was about a mile from me, is documented, and was corrected. There may have been others that were corrected without any announcement, and there may be still others that are unknown. Of course, dumping rainwater into a system designed to handle only sewage is a fast way to overwhelm any system.

So as I understand it, the problem is three-fold:

(1) The deep tunnel isn't large enough. Ultimately, the systems will have to be separated. That is the elephant in the room.

(2) Measures to make the deep tunnel look like it works have literally backfired.

(3) Human error. Probably sizing pipes a little on the small side, connecting things wrong, etc.

So now the MMSD and the local governments are trying to redirect the problems by pointing fingers at homeowners. And that is what this entire thread was about. Thankfully, they didn't get away with it, but I'm sure they will try again. At this last meeting, BTW, some members of the board apparently upset at the outrage from residents said everyone should be forced to add sump pumps and disconnect their drain tiles from the city. The village manager, who apparently wasn't bright enough to understand the percolation aspect of the lateral project, has apparently studied-up and said something like "the city's rainwater collection at the street cannot currently handle everyone switching to sump pumps."

So here we are.

Looking at that elephant in the room.

Sorry for the long post, but I thought I'd document this because I know this battle is going on in other parts of Milwaukee, and other parts of the country, too. People should know the lengths governance will go to in order to deflect a problem.

[David Weaver]

Phil, your whole scenario just seems to confirm my tin foil hat notion that most people can't examine a situation, deal with likelihood and solve a problem. I don't know if it's fatigue on the part of everyone else, but the "leaky laterals" issue sounds like bunk to me, too, especially on a quick back up. It doesn't sound like anyone is really interested in solving the problem, and the newspaper journalist is maybe doing nothing other than repeating words they've heard, so you may get nowhere with them making logical arguments. If they can't understand why a flash flood through the floor drain isn't related to high volume a week later, you've got little chance other than going elsewhere to find out what the real issue is.

(EDIT: I missed the 7/2 post that you attributed to a geological engineer. It must've made too much sense to the newspaper writer. One wonders whether it's ego, laziness or stupidity that's to blame)

The focus has been on banned sources of water here, and while not perfect, I do believe the effect has been measurable. It's not every house all at once here, it is a dye test required upon sale of a house, and the townships don't allow a sale to go through until any external water sources found as part of a dye test are redirected away from sewers.

[Brian Elfert]

So, they spent billions on a tunnel to fix the symptom rather than fix the problem? Why not spend those same billions to fix the real problem? Many of our sewage and water pipes in the USA are nearing the end of their service life and need to be replaced anyhow. Set up a 20 to 30 year plan to rebuild all of the streets and separate the sewer at the same time. The small town (10,000 people) my grandparents lived in rebuilt all of the streets in the 80s and separated sewer and storm at the same time. It can be done.

If the new lines are for sewage only then they should be able to install smaller lines to replace the larger lines that had to also handle storm water too. Yes, larger pipes can hold more water, but the sewage system should never be designed for the pipes to act as a holding tank.

[Dan Hintz]

Phil,

Not my field, but I always enjoy learning new engineering fields, especially when there's a failure to be learned from. Keep talkin'...

[ray hampton]

Everybody complain about the weather BUT NO ONE do anything about it, most people head uphill to get away, 1/2 inch rain fall will flood a city if the storm drains are stop up

[Phil Thien]

So, they spent billions on a tunnel to fix the symptom rather than fix the problem? Why not spend those same billions to fix the real problem? Many of our sewage and water pipes in the USA are nearing the end of their service life and need to be replaced anyhow. Set up a 20 to 30 year plan to rebuild all of the streets and separate the sewer at the same time. The small town (10,000 people) my grandparents lived in rebuilt all of the streets in the 80s and separated sewer and storm at the same time. It can be done.

If the new lines are for sewage only then they should be able to install smaller lines to replace the larger lines that had to also handle storm water too. Yes, larger pipes can hold more water, but the sewage system should never be designed for the pipes to act as a holding tank.

I'm right there with you Brian, I think even those that pitched the deep tunnel would take a do-over if it was offered. Of course, that isn't an option and any time you point to the failure of their "solution," they deflect.

A couple of years ago they started singing a new tune, that the deep tunnel was never supposed to be a 100% solution, that some waste releases would still be inevitable during/after heavy rains.

The problem is, my recollection (it has been years) was that the deep tunnel was supposed to reduce the frequency of untreated releases to approx. two per year. We've had instances of two in 24-hours. We've had 3-4 in a week. We've had gobs in a summer. That certainly wasn't part of the pitch, they are revising history (in terms of what was promised).

Had they just committed to doing the project right, we'd have already had a completely separated system for years now (the deep tunnel was started in 1977 and construction continued until 1993!). Here is some reading for anyone interested: http://www.mmsd.com/deeptunnelhistory.aspx

What is one of the most oft-quoted sayings here in regards to buying a quality tool? "Pay once, cry once."

We're going to pay twice, in the end. It is only a matter of time before other states and the feds force us to separate the sewers. At least partially, separating enough until the problem is solved or the frequency of discharges is reduced to an "acceptable level."

[Brian Elfert]

I had no idea this tunnel project you mentioned started way back in the 1970s. $3 billion in 1970s money was a lot of bucks for a band-aid solution. What would cost if built today, $10 billion maybe. Construction costs have gone out of sight since the 1970s.