Sand Filter Joint Sealing

Henrico, Virginia

The Job:

Two underground stormwater sand filters at an apartment community wouldn’t hold water. The structures, which were assembled from 10′ diameter metal pipes needed to pass a water loss test before the property could come off bond. Previous repairs attempted included installation of internal joint rings and seals, which did not stop enough flow to pass the water loss tests.

The Challenge:

The proposed repair had to accommodate multiple layers of previous repairs. The joints included four different materials–aluminized metal, galvanized metal, neoprene, and polyethylene. The structures were bedded in washed #57 stone, and were connected to the stormwater drainage system, so subject to live flow.

CJGeo’s Solution:

Sprayed high density polyurethane/polyurea hybrid to seal the joints internally. In addition, chemical grouting for joints which had been repaired previously using internal bands and polyethylene seals. The chemical grouting repair was designed to minimize loss of chemical grout into the surrounding stone beds. The previously-installed internal seals and bands were left in place and encapsulated in the joint sealant.

CJGeo large diameter pipe repair crew installed chemical grout to seal the leaking joints. Immediately after the sealing was performed, the structures were tested by the municipality. Neither structure leaked any water after CJGeo sealed the joints.