Civil Engineers - Could sewage backup into a home in power outage?

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A GI friend of ours is concerned that IF power were go out for an extended period of time, that our city's non-gravity-flow sewage system could backup and out of toilets, sinks, etc.

The theory is that there are pumping or "lift" stations which help the effluent on it's merry way to the treatment plant. Without help from these lift stations, would sewage simply backup and out of the lowest points in the system?

This is a BIG concern for GIs - because a sewage filled home is a home in which you could no longer stay.

Any feedback appreciated.

-- Greg (balzer@lanset.com), August 14, 1999

Answers

Its certainly possible, as its happened to people before.

But the specifics depend so much on your locaion/situation. I would know, however, where my sewer line is, how to access it and have 'a plan' on how to disconnect/plug the outgoing line if you need to --- its not that hard. You need to check out your situation with the city sewer department or engineer --- most are NOT your enemy and will help you (at least with info) if they can.

-- Jon Johnson (narnia4@usa.net), August 14, 1999.


We are planning to get the plumber in to install this thing--I forget what it's called. Also, someone on a previous thread told in detail how you could install this other thing. I think getting the plumber in will cost us about $140. We don't need no stinking sewage.

-- Mara Wayne (MaraWAyne@aol.com), August 14, 1999.

Jon -

Good suggestion about talking with the City. I can't remember the specifics, but our friend was alerted to this possibility by a City Utility provider. (I can't recall if it was a water/sewer/whatever person).

Mara-

I believe the device is a valve which either allows the connection to be "shut-off" or a "flapper-type" valve which only allows flow AWAY from one's dwelling.

This area is suburban, and in many homes to install this device would require tearing up one's driveway. This raises the price substantially.

Thinking beyond the personal application of this problem - I wonder how many homes in a City might quickly become un-inhabitable due to this problem? AND imagine the associated problems with health and sanitation.

-- Greg (balzer@lanset.com), August 14, 1999.


I had one installed last year--I thought it is called a back-up valve and it works on a flapper principle---My plummer said that if I was worrying about sewage, to worry about the basement or lower level because the stuff seeks the lowest level and that it would flow in the streets befor it would reach up to the 1st floor--people storing their food in their basements need to think this through. It was a simiple hr long job at my place and cost just over $100. I can't imagine my world awash in sewage.

-- mary (souldance@pop.uswest.net), August 14, 1999.

I contacted the waste water engineer in our small town about backup. He was extremely helpful and explained it to me this way. Waste water systems are gravity systems which allow water to flow to the lowest point and then pump it to a higher pipe to continue on it's way. I asked where the nearest pump was to my location. Luckily it was almost a 1/2 mile away. I then asked if it would back up into the nearest house. He said probably not, it would first bubble up through the ground at the pump location. I have made a mental note to avoid these pump locations if power goes down for long. Our utility company has leased huge generators for the entire water system (one of the head guys is a GI). This is great for our water system but actually bad for the waste system. They aren't able to put generators at all the waste pump locations. Most people don't even know these pumps exist let alone where they're located. How many ways can you spell disease?

FIND OUT WHERE THOSE PUMPS ARE!!!

-- Steve (bibleout@tds.net), August 14, 1999.



Steve -

If your location is requiring pressurized pumping stations for sewers, then expect your utility to suspend water service until contingencies are in place. Without water, there is very little chance of sewage spills. So if the lift pump stations are without power, the prudent thing will be to turn off the water until a plan is in effect.

-- Michael (mikeymac@uswest.net), August 15, 1999.


Mike,

What you say makes sense. But as you know it takes considerable time for people to realize what may be the consequences of their actions ie. providing emergency power for water supply but not for waste water systems. I'm going to try to ask the water engineer about this. I also wonder if just the water in the elevated tanks would be enough to cause a spill? Because of this thread I'm going to find out.

-- Steve (bibleout@tds.net), August 16, 1999.


Greg, you do not have to tear up your driveway! A plumber can install a back flow prevention device by cutting into your sewage pipe in the basement. I also came across one of these devices recently at the hardware store for about $6, so if you are handy you can do it yourself...

-- Deb (deb@needhelp.com), August 16, 1999.

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