Isn’t a fiberglass pump station going to float out of the ground with a high water table?
A/ No, not with a MOPS pump station. We calculate our flotation figures very conservatively. The weight of the wet well, any residual water within the wet well, pumps and other equipment is neglected. Soil friction and the cone effect of soil being pushed to the sides when an object is ejected from the ground are neglected. Plus, a safety factor of 10% is added above and beyond. If the calculations demonstrate ballast is required, then the proper amount of cement is added to an oversized base flange. Quite often with smaller stations, no ballast is required with the oversized anti-flotation flange, saving money for the client and scheduling issues with the contractor.
