Main Sewer Line Cleaning in Elk Grove, CA

Elk Grove went from a small rural community to one of the larger cities in the Sacramento region across the 1990s and 2000s, which means almost all of its sewer laterals are modern plastic in sound condition. Material failure is rarely why we are called. Ground movement and grade are.

The ground here is Sacramento Valley floor, and it has a characteristic that matters: much of it carries dense clay and claypan or hardpan layers, cemented horizons that sit at a consistent depth and are far less permeable than the soil above. Hardpan has two consequences. It perches water above it rather than letting it drain away, so the soil around a lateral can stay saturated well after a storm, and it makes excavation harder because the layer frequently has to be broken rather than dug and it often sits at around the depth a lateral runs.

Clay with a real shrink and swell capacity plus a Central Valley climate of completely dry summers and wet winters gives a large annual volume change. On plastic pipe that movement does not open bell joints, because plastic flexes and has very few joints, but it does concentrate stress at the fixed points, where the lateral passes through the building and where it ties into the main. Those are the first places we look on a newer line here.

The dominant finding, though, is loss of grade from pad settlement. Rapid tract development across this flat valley ground involved filling and levelling, and fill keeps consolidating for decades. On very flat ground the designed fall in a lateral is shallow to begin with, so there is almost no margin: a dip of an inch or two leaves standing water and starts collecting solids.