Water Main Relining 1

[cr1973]

I am considering lining some old cast iron pipes, in lieu of dig and replace. The process appears to involve cutting open the existing main, pull a liner through, then inflating this liner with water or steam. Once the liner cures, a robot runs inside the pipe and cuts holes at the service taps.

Anyone here tried this before? I am curious how long this process takes, and how to run a secondary water system to keep residents in service as the main is being relined.

 

[bimr]

There is not much of this work. The reason being is that the cost is on the high side.

At the present time, it is more cost effective to install new pipe with directional drilling than attempt to line water mains.

It is more feasible to line sewers than water mains.

 

[greggy]

We have had much success with old-fashioned cement mortar lining of mains in streets too difficult to dig up the entire length, like brick or utility-laden. I think we can go about 300 to 500 feet per lining run, with locations usually where the valves are, which we most of the time repalce.

The scraper and lining machine can go through 22.5 degree bends, but anything more than that you have to dig up.

The process involves scraping the main, pigging it to remove all debris, mortar lining followed with a trowel (funnel), cure, inspect, replace valves, refill, sterilize, and back to service in about 8 days. Bypass lines feed the customers during the interim, so in cold areas we have to do this in non-freezing weather.

 

[dicksewerrat]

Water main lining by cured in lace pipe. isstarting to become more readily available. there are contractors that do this. Go to

http://www.trenchlessonline.com

for more info. Too bad you didn't post in early Jan. there have been 2 national trade shows since then. UCT and NASTT's No-Dig. Both shows have a web site.

http://www.nodig.com

http://www.uctonline.com.

You can get exhibitor names from both to call.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[bimr]

Insituform is one of the companies that do water main lining.

http://www.insituform.com/content/344/about-thermopipe.aspx

 

[dicksewerrat]

Time frames for CIPP is fairly short. Each section of line would be 1 day. The time for setup, cleaning, chlorinating, testing and reconnect will size and condition dependant. You will hav to excavate each cross, hydrant gate and line gates.

You should also calculate the carbon footprint for 'cut and cover' and the CIPP process to help sell the process to the owners.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[bimr]

The price for directional drill pipe installation has decreased so much that it is attractive economically when compared to open cut excavation. It is also a more attractive alternative than lining as there are only a few firms capable of lining. This is one of the reasons that the cost of lining water mains is generally higher.

It is also easier to transfer the services to new pipe than it is for lining projects. Unlike with lining projects, services can be transferred to new pipe with relatively minor distruption.

 

[dicksewerrat]

BIMR,
When using CIPP to line a water main, there is no excavation at the service lines. It is all done with robots inside the pipe. When HDD replacement you have to dig each service to reconnect.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[bimr]

The point is, if you line water mains, the services will be off line for several days while you install the lining and wait for the disinfection test results.

If you install a new pipe, each dividual service will be shut off for less than a day while you transfer the service from the existing water main to the new water main.

Maintaining service will be required for lining projects.

 

[cr1973]

Thanks all for the posts.