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View Full Version : retaining wall construction on a lake bed?


seacoastlandscape
02-05-2010, 11:42 AM
In the middle of quoting a job for a client that lives on a lake. They are looking to have a techo mini-creta retaining wall built right at the edge of the lake. The lake is drained down for the winter but after speaking with the town, within the next few years dep will no longer allow them do this. This means in the future and if the lake reaches a high point during the spring etc part of the wall could be under water. I have never had to deal with this situation before and am unsure of the proper construction to ensure the integrity of the wall for the future. i would assume there are some differences needed for drainage etc. The supplier and engineers at Techo were no help and told me to hire an engineer. Anyone have any experience with this?
Thanks

SoDak
02-05-2010, 12:21 PM
http://www.rockwoodwalls.com/literature/Classic-Install-Manual-noPCS-ENG.pdf

This is Rockwoods installation guide. Page 17 has instructions on installation for water applications. I did one 5 years ago on a lake that can get up to two feet of ice on it and it has held up well. I would still probably involve an engineer.

dubb
02-05-2010, 12:32 PM
whats the dimensions on the wall? i would possibly consider using a bigger block, if they are not going to let the water down you will always have most of the wall under water and if it rises over the top of the wall then you could be in a mess. We have currently been working on a seawall since the beginning of january but only have about a week and a half of work in on the job so far because it has been raining like crazy here and everytime it rains the water goes up. We are building this wall with redi rock and it is about 210'x7'6". engineer called for 1ft. of gravel for the footer, 1ft. of gravel behind the wall, geotextile fabric that wraps from behind backfill, under footer, and then out in front of the wall with a complete block buried. We will then add riprapt along entire shoreline. You need to check with your city hall and see what requirements/restrictions they have.

DVS Hardscaper
02-05-2010, 02:35 PM
yeah, you'll need to build it good.

GreenMonster
02-07-2010, 09:23 AM
Techo has given you the best advice. Hire an engineer.

I would also go would something bigger than mini creta. I use a lot of Techo, but I wouldn't go with anything they manufacture that is smaller than the Suprema.

The wall will likely be engineered with more grid than normal, more backfill stone than normal and a lot of buried block than normal. It will be important to completely wrap the base in Geotex to avoid washout.

DEP - are you in Maine?