Note to readers: This post was updated on July 16, 2026 to update seasonal drain maintenance guidance for current rain patterns and add links to our related drain and sewer guides. We refreshed the details below so the advice reflects how we approach this work today.
When the rainy season hits the San Gabriel Valley, it tends to arrive all at once, and the drains that have sat quiet all summer suddenly have to handle a lot of water fast. A little prep work before the first storm can save you from a flooded yard, a backed-up sewer line, or worse.
Area drains and catch basins
Every area drain around your property, patio, and pool deck should be flowing freely before the rains start. Sump pumps and catch basins that eject water need to be cleaned out roughly every six months depending on how much debris collects. A pump jammed with leaves and dirt will fail right when you need it most, and that’s how a hard rain turns into a flooded yard or garage.
How often should drains be cleaned?
Every drain ages differently. Lines with nearby trees are more prone to root intrusion, while others collect more sand and leaf debris. As a rule, every drain line should be cleaned at least once a year. It’s a lot cheaper to schedule that during normal business hours than to pay emergency rates at midnight during a storm. A simple test: run a garden hose into the drain. If water backs up or drains slowly, it’s time to call a plumber before the rain does the testing for you.
What causes the clogs
- Area drains: leaves, sand, dirt, and root intrusion, especially after a dry stretch of years when roots seek out any available moisture
- Sewer lines: cooking grease, wipes, and root intrusion in older cast iron lines
Grease and food waste acidity can actually eat away at cast iron pipe over time, so keeping grease and oils out of the kitchen sink protects more than just the drain, it protects the pipe itself.
Preventive steps before the storm
- Flush area drains and catch basins with a garden hose to confirm they’re flowing
- Make sure landscapers aren’t blowing leaves and dirt into drains or basins
- Skip the grease, oils, and orange peels down the kitchen sink
- Don’t treat the garbage disposal like a trash can
- Get a sewer video camera inspection if you’ve never had one, especially on an older home
When to call a pro
If a hose test shows slow drainage, or it’s simply been more than a year since your lines were serviced, get ahead of it before the rain does. We use proper sewer cable and equipment to clean both area drains and main sewer lines, and we always confirm the caps are back on and the area is cleaned up when we’re done. For more on catching problems early, see how to tell if your drain is clogged or your sewer is damaged and roots in pipes: signs, removal, and prevention. Call us at 626-448-6455 to schedule before the next storm rolls in.
