×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

maximum drop depth allowed in the sewage manhole

maximum drop depth allowed in the sewage manhole

maximum drop depth allowed in the sewage manhole

(OP)
Hi all,
can any one have the idea about the maximum drop depth allowed in the sewage manhole with 1000 mm pipe, please provide references for the same.

Regards,

RE: maximum drop depth allowed in the sewage manhole

One would have to contact the local sewer agency that you are working with. Different agencies may have slightly different interpretations as there is no universal standard.

RE: maximum drop depth allowed in the sewage manhole

bimr hit it on the nose check with local waste water agency.

RE: maximum drop depth allowed in the sewage manhole

(OP)
Thanks

RE: maximum drop depth allowed in the sewage manhole

As others have noted it is always wise (or imperative) to check with local authorites, and particularly any AHJ's. I am aware however, ASCE MOP No. 60/old WPCF FD-5 gravity Santary Sewer Design and Construction does cite multiple problems that may occur as a result of drops and deep drops, and it says of drop manholes, "Drop manholes should be used sparingly and, generally, only when it is not economically feasible to steepen the incoming sewer. Some engineers eliminate drops by using vertical curves. It would appear that this should be a general rule for elevation differnces of less than about 1 m (3 ft) and often for larger drops as well."

RE: maximum drop depth allowed in the sewage manhole

(OP)
Thank you rconner, it is very helpful.

RE: maximum drop depth allowed in the sewage manhole

Attached is a typical detail for a drop manhole. Drop manholes are typically required if you are taking more than 2 ft of drop inside the manhole. If you have a drop manhole, then the drop outside the manhole may be much larger.

RE: maximum drop depth allowed in the sewage manhole

(OP)
thank you bimr

RE: maximum drop depth allowed in the sewage manhole

(OP)
Dear rconner can you share the code ASCE MOP No. 60/old WPCF FD-5 gravity Santary Sewer Design and Construction

RE: maximum drop depth allowed in the sewage manhole

fyi http://ascelibrary.org/page/books/s-mop (and copywrighted ASCE manuals of practice are not really "codes", but are as explained at that web page or the front matter of the various MOP's)

RE: maximum drop depth allowed in the sewage manhole

Are you laying a new pipe? If so, put it in at the flow line of existing manhole. Dropping helps get the H2S to come out of the sewage. This will corrode your manhole. Another thing is that us guys that do or did go into live manholes don't like the "Drop Manhole" idea. Have to take a shower in clean water afterwards.

Richard A. Cornelius, P.E.
WWW.amlinereast.com

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources