×
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

Ocean outfall installation techniques

Ocean outfall installation techniques

Ocean outfall installation techniques

(OP)
I need to install a outfall pipeline at a dissipatave beach (1:80, fine-medium sand, low energy enviro).  The pipeline will be approx. 250>350mm HDPE or similar.  The pumped material will be clean seawater, discharge from beachface dewatering (beach drainage) system.  Max. water depth probably only 1m at low tide (tidal range 1.4>1.8m). total length say 250m from front of dune system.  Distance to low water 100m average.

I would be interested to hear about any inovative low cost installation techniques - particularly seaward of the low tide mark.

Regards, Trevor
beachdrainage.com

RE: Ocean outfall installation techniques

If the pipe is to be installed in a trench and then backfilled, I suggest a small backhoe dredger for digging the offshore trench (seaward of low water mark), and land based excavators for the inter-tidal zone.  The pipe string can be fabricated above the high water line (if there is enough room) and dragged down the beach and installed in the trench at low water using the same plant mentioned above.  Concrete weight collars on the pipe or stone mattresses over the pipe can be installed to provide temporary stability for the pipe until the trench is backfilled.  Very general description, but I think it's the cheapest method.  Looking for a company to install the pipe?  We have installed many outfall pipelines in UK and overseas.

RE: Ocean outfall installation techniques

I agree with the answer from desm except that I would use land based plant for the excavation in 1.0m of water. It depends on the wave action, but a pedestal mounted excavator will easily work in 1.0m of water and it would avoid the cost of mobilising a backhoe dredger. We have also installed many outfalls in the UK and around the world, and would be interested.

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