Navarro Mills Dam Waterstop Repairs

The Navarro Mills Dam is an earthen dam with a straight-axis concrete gravity control structure consisting of 13 monoliths. The original waterstops have failed in 4 joints of the non-overflow monoliths and leakage was flowing through the control structure into the earth-fill abutment sections creating erosion risk. A project to repair 4 leaking joints was needed to resolve the concern.

SCOPE OF WORK
At each of 4 leaking monolith joints, a remedial waterstop was to be installed to mitigate the leakage through the control structure. A 6” diameter borehole was drilled along each joint from the top deck to a depth of 5’ into the foundation. Each borehole was inspected for any voids or honeycombing in the concrete sidewalls of the borehole. A neat-cement grout was used to repair any defects within the borehole that could create a potential leakage path around the seal.

After a final video inspection of the borehole, Emagineered Solutions’ CYLutions™ remedial waterstop cyinders were installed in a column within the borehole up to 3’ from the intake deck. A mechanical packer was placed on top of the cylinder stack to resist uplift of the cylinders as they expand in the presence of water.

RESULTS
In the weeks following installation of Emagineered’s CYLutions™ remedial waterstop cylinders, the leakage at all joint locations was dramatically reduced or eliminated.  The new watestop seals remain effective today.