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How to navigate retaining walls?


LawnSite Senior Member
Bismarck, ND
We are bidding on two installs. Both have retaining walls that we will have to get by. One is regular retaining wall blocks and one is 8' landscape timbers. Both are about 4' high. The POC is on one side and the area to be irrigated on the other.

Homeowners will not allow any surface pipe over the walls. What are our options to get from one side to the other? A first for us.

Thank you for the help.


Critical Care

LawnSite Bronze Member
Central Oregon
It certainly sounds like you probably have to either go around or under.

The retaining walls may have buried deadmen, but you should still be able to use a garden hose or pvc with a high pressure nozzle on the end to bore down under the walls. The landscape timbers shouldn't have any problem at all, but if the other one isn't mortared in you could have some blocks move.
I agree, putting a sleeve under a properly prepared interlocking paving wall is a royal pain.
Not only do you have to go underneath with the sleeve but the reinforcing area is a real @#$%$ to get through with out disturbing the drainage field/integrity of the wall.
Provided you have an alternate route I'd say route around the wall.
If not, make 'em pay for going under the wall.
It's the customer's fault they weren't thinking about ancillary utility services and should have had sleeves or conduits included with the original install.