Hi, we are working on solving some water issues in our old foundation basement, so that we can semi-finish it. We've had 2 companies come to look, and they gave opposite plans for the sump crock

Plan A: Put in a *deeper* crock, because it's better to have the water table lower under the slab

Plan B: Put in a *shallower* crock, because too deep a well means your pump works too hard, plus you have too much flow under your slab and that moving water erodes things.

Our current crock is about 25" deep. With our current pump setting we have maybe 6" of water in there now. There are some damp spots in the slab, especially after a hard rain. It's an old basement, from the 1930s, with some unused old clay sewer pipes embedded in it. The soil is clay and poorly draining, and we get a fair amount of rain/snowmelt.

Changing the sump crock is just part of the proposals but I was confused by the opposing advice! Does anyone know how you calculate the "right" depth? Thanks a lot!