Storm and yard drain cleaning in Los Angeles before the rain finds your foundation

Southern California's long dry season works against yard drains. Leaves, eucalyptus bark, palm fronds and windblown dust settle into catch basins and lines for months with no rain to flush them. By the time the first real storm arrives, the pipe may be half full of compacted silt.

Roots are the other common cause. Shallow corrugated drain pipe and old clay storm lines sit right in the root zone of lawn trees and hedges, and roots go after the moisture that lingers in the pipe long after the last rain. Corrugated pipe is especially vulnerable because its ridges trap silt and its seams split easily.

• Leaves and needles packed into grates
• Silt and mulch washed in from planters
• Roots through corrugated or clay joints
• Crushed pipe under driveways or walkways
• Gravel and construction debris from past projects

Rainwater and sewage should never share a pipe at a house. Yard drains carry storm runoff to the street gutter, a curb outlet, a drywell or an approved dispersal area. The sewer carries waste from toilets and sinks to the city main and the treatment plant.

Connecting downspouts or yard drains to the sewer is prohibited, and it causes real trouble: heavy rain overloads the lateral and can push sewage back into the lowest fixture in the house. If we find a storm line tied into the sewer during cleaning, we tell you and can reroute it. A blocked sewer is a different job, handled through main sewer line clearing from the cleanout.

Light debris in a short line comes out with a hose flush and a hand cable. Longer runs, and pipes packed with mud, need a water jetter, which scours the full diameter and pushes silt toward the outlet. We use high-pressure jetting with a nozzle sized for thin-walled plastic so we do not split corrugated pipe.

Roots call for a cutting head on a cable machine, followed by a jet flush to carry the cut material out. After cleaning, we run a camera through the line to check for crushed sections, separated joints and spots where the pipe slopes the wrong way. A drain that clogs every year at the same distance almost always has a sag or break at that point.

If the camera shows broken or crushed pipe, we replace that section with smooth-wall PVC, which carries silt through much better than corrugated pipe and resists roots at its glued joints.

The best time to clean yard drains is early fall, before the first storm. Lift each grate, scoop out the leaves and sediment by hand, and run a garden hose into each inlet for a few minutes. If water backs up or drains slowly, the line needs a professional cleaning.

Check that every downspout connects firmly to its underground fitting and that splash blocks have not been knocked aside. Keep mulch and soil a few inches below grates so they do not wash in during the first heavy rain. On hillside lots, clear the terrace drains and V-ditches too, since a blocked bench drain can push water toward the slope and the house.