Cleanouts in an old storm drain pipe

[KenRad]

I'm looking for either an old plumbing engineer, or someone who is familiar with underground piping practices from the early 1970's.

Our building has a first floor office that was built in 1971. Under the 4" slab, there is an underground 12" RCCP storm drain pipe running the length of the office that carries water from roof drains in that part of the building. During some recent heavy rains, we have had water coming up through the carpet. My first thought was that the water was leaking through cleanout covers.

I'm trying to determine if they would have installed cleanouts along this 100' straight length of 12" RCCP. None are shown on the construction drawings, and the entire area is carpeted. I don't want to pull up the carpet if there's a good chance that there are no cleanouts to be found.

---KenRad

 

[dicksewerrat]

Have a plumber look at the pipe with a TV camera. Looking for misaligned joints, no gasket in joint etc. Also look for sediment in the line. Clean the line. Check the calcs they used to size the line, Did they use a high enough rainfall, etc. If the line has problems, ask contractors for costs to CIPP the line. My guess would be a general lack of maintenance and ispection since 1971.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[dicksewerrat]

sorry 'inspection'

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[MechEngNCPE]

Definitely do a camera pass through, you would see cleanouts on the drawings, typically. I'm thinking dickswerrat is on the right track. You could do a flow calc and check to see if other roof drains /scuppers are clogged that might increase the required flow to this drain. Any plumber could probably tell you what is going on with a one hour visit.[highlight #FCE94F][/highlight]

 

[IRstuff]

How far from the downleg was the water seepage?

I've had a downleg that cracked just above the sill in my old house. The water seeped out and wrecked a couple panels of drywall and the carpeting.

TTFN
faq731-376

 

[dicksewerrat]

I would almost bet the water is coming from the joint between the RCP and the downpipe from the roof. But the TV project will get you all the answers.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com