Flooding In New Construction Building - Worst Swimming Pool Imaginable

by losthorse   Last Updated September 23, 2018 19:21 PM

This weekend, water was observed flowing up, through the floor and through other joints, into the building - making the worst swimming pool imaginable.

Some Background

We currently have a project constructing a shop/garage in the Texas hill country. The site is above the flood plane and water table. The site is on the side of a hill; the ground is overwhelmingly limestone.

Construction has halted due to unusual and extensive rainfall in the area for the last several weeks.

Please see photos below for details of the water penetration problems.

The question:

What is the appropriate course of action considering:

  • the building has a poured concrete foundation with monolithic curb 12 inches tall
  • the below grade walls are 12 inch CMU and filled with concrete
  • we are in Texas, most people don't have a basement
  • most local contractors don't have experience working on below grade projects like this one (see above)
  • we followed the engineers instructions as closely as possible
  • we would prefer not to remove the back fill and start over

Is it possible to completely seal this building from the inside? If so, what products are most appropriate?

As an aside: There are several problems with this project including the floor (the top of the foundation) being out of level by several inches. During previous rain activity, prior to the roof installation, water was observed pooling in the north west corner. It was believed that this would not be a problem after the building was finished and watertight.


This is the topography of the area with the site in red.

topography of area

site plan

This is the site plan with the building in red.

site plan

longitudinal section

This is the longitudinal section with the below grade portion in red.

longitudinal section


This is the engineering for the walls, including the french drain and waterproofing.

wall engineering

floor plan

This is the floor plan with known water penetration areas in red.

floor plan with problem areas



Over view with known water penetration areas in red.

inside with labels

Saw cut

Flowing from saw cut; seems to be high flow with visible water movement and pooling ~2 inches deep.

water from saw cut

Wall/Floor Joint

Flowing from wall/floor joint; seems to be high flow (but less then the saw cut) with visible water movement and pooling ~1 inch deep.

water from wall/floor joint

Floor Joint

Flowing up between floor and concrete drive outside; seems to be high flow with visible water movement but minimal pooling.

water from floor joint

French Drain Working

This is the french drain flowing at max capacity. The same is visible on the other side of the building. french drain water flowing

Related Questions

Solving active sump issues

Updated March 01, 2016 01:09 AM

Capping a Downspout

Updated October 02, 2018 20:21 PM

Basement cinderblock wall tops - cover or fill

Updated July 14, 2018 15:21 PM