I am to design the structure of a lake surrounded by mountains all round. How do I drain the water under floor

Question

The rainwater will flow through the slopes to get under the floor and produce upthrust. It may rupture the floor.

Answer 1

You'll need to talk to a contractor about this, but I'll bet he will recommend that you pour the slab and footings on top of a bed of compacted 3/4" gravel. The gravel base must be sloped to freely drain all water flowing thru it into the lake.

You should also install a drain tile system around the circumference of the foundation and make provision for the installation of several sump pumps to get rid of the water collected by the drain tile system.

I believe that this is a pretty standard solution for a problem like this.

Answer 2

The only lakes i know about are filled with water. The water in the lake will equalize with the water in the underflow so there is no "upthrust". After storms, the excess of water will cause the level contained in the lake to rise so pressures are always equalized. It sounds as if you are designing a boat or swimming pool instead of a lake. For a swimming pool, the weight of the water in it is always more than the pressure outside, if this were not so, then water would be squirting up from around the perimeter of the pool, a most unusual circumstance indeed. but if that can happen in your instance, line the outside of the pool with gravel drain and use a buried pipe to a sump pump, no different than the method used to protect a building basement.

Answer 3

Make the floor of the lake thick enough (heavy enough) so that it does not float/ or rupture the floor.