This valve chamber assembly was located in a high groundwater area. As an experiment, bentonite was placed around the chamber during construction to prevent water infiltration through the chamber joints and pipe entries.

 The bentonite consisted of bagged powder bentonite with loose bentonite placed in the gaps and joints. The chamber was completely surrounded with the bagged bentonite, as well as each pipe entry (middle picture)



Shortly after back-filling, the water level rose and infiltrated into the chamber through a pipe entry (top picture). Mountain Waterproofing was contracted, through the construction specifications to install the DryVault system around each pipe entry. The first pipe entry was sealed using the DryVault (bottom picture).


Subsequently, the second pipe entry started to leak as the water level rose around the chamber. The leak through the first pipe entry maintained an exterior water level, which increased once the pipe entry was sealed.

The DryVault system was installed on all three pipe entries and the water infiltration was completely stopped.