That soggy corner by the patio, the gutter spilling over your front door, the puddle still sitting there two days after a storm: none of it shows up in a dry October, and all of it shows up in December. A yard drainage checklist is a short walk-around that tests how water leaves your property before winter rain does the testing for you. Do it now, and small problems get fixed while the ground is dry. The six checks below take an afternoon, and they tell you whether you need a quick repair or drainage installation and repair.
J&P Landscape, a licensed design-build landscape contractor serving San Jose, Silicon Valley, and the wider Bay Area since 1984, recommends a six-point yard drainage checklist before the rainy season starts. About 82% of San Jose’s yearly rain falls between November and March, according to the National Weather Service, so finish by October. Clear the gutters and downspouts, confirm the ground drops at least 6 inches over the first 10 feet from your foundation, test patio and walkway drains, clear swales and yard drains, check retaining wall weep holes, and switch off your sprinklers. Much of Santa Clara County sits on expansive clay soil that drains slowly, so even a small low spot can hold water for days. If a check fails and a quick fix doesn’t solve it, that’s when to call a drainage contractor.
Start With the Roof: Gutters and Downspouts
Every drop that lands on your roof leaves through the gutters, so the checklist starts there.
1. Clear the gutters and check every downspout
Scoop out leaves and sludge, then run a hose along each channel. Water should reach the downspouts freely, with no pools in sagging sections.
Next, look at where each downspout ends. Water should land at least 4 to 6 feet from the foundation, and farther if your soil is heavy clay. Point it away from neighbors, walkways, and driveways, too. If a downspout feeds a buried pipe, run the hose through it and watch the outlet. Weak flow usually means roots or a crushed section, and it’s a common reason a clean gutter still overflows.
Check the Ground Around Your Home: Slope and Hard Surfaces
Once roof water is under control, look at where it goes when it hits the ground.
2. Measure the slope at your foundation
Soil should fall at least 6 inches over the first 10 feet away from your house. Push a stake in at the foundation, run a string level out 10 feet, and measure the drop. Soil settles against foundations over the years and leaves a shallow trench that fills fast in a storm. Pull mulch and bark back from siding and stucco, too, since they hold moisture against the wall. Clay swells when wet and sheds water instead of soaking it up, so a flat or backward grade matters more here than it would in sandy soil.
3. Test your patio and walkway drains
Hard surfaces should shed water away from the house at about a 2% grade, roughly a quarter inch of fall per foot. Hose water across your patio and watch where it travels. Then lift the grates on any channel drains or area drains, clear out leaves and grit, and check the pipe below. A puddle that’s still there a day after real rain points to settled pavers, a flat slab, or a blocked drain.
Follow the Water Away: Swales, Drains, Walls, and Sprinklers
Water that leaves your house still needs somewhere safe to go.
4. Clear the swales and yard drains
A swale is a shallow, wide channel that guides runoff across your yard to a safe exit. Pull out weeds, thick thatch, loose rock, and stacked firewood that block it. Next, lift the grate on every catch basin and yard drain, scoop out the silt, and pour in a bucket of water to confirm it drains.
5. Check the retaining wall drains
Water trapped behind a retaining wall adds heavy pressure, so the weep holes near the base and any drain outlets must stay open. Staining, damp patches, or bulging mean water is already stuck behind the wall. Bulging is a call-a-contractor sign, not a weekend fix.
6. Switch off the sprinklers
Turn the timer off or to rain delay before the first storm. Watering saturated clay only adds to runoff. Before you shut it down, run each zone once and look for geysers or soggy patches, because a leaking valve keeps feeding a low spot all winter.
When the Checklist Finds a Problem
Some fixes take a hose and an hour, and others need a drain in the ground. Use this table to sort what you found.
| What you see | Likely cause | Try first | Call a contractor when |
|---|---|---|---|
| Water pools within 10 feet of the foundation | Settled or flat grade | Add soil and restore the 6-inch drop | Fixing it needs a new drain or wall, or water reaches the slab |
| Clean gutters still overflow | Blocked buried downspout line | Hose test and clear the outlet | Flow stays weak after clearing |
| Patio puddles last a day or more | Settled pavers, flat slab, or blocked drain | Clear grates and joints | Pavers have sunk or the slab holds water |
| Retaining wall is damp or bulging | Blocked weep holes or drain | Clear holes and outlets | Any bulge, lean, or crack appears |
| Lawn stays soggy 2+ days after rain | Compacted clay with no exit path | Aerate and clear the swale | The spot returns every storm |
A checklist has limits. It can’t fix a lot that slopes toward the house from edge to edge, or runoff coming from a neighbor’s higher yard. Those need regrading or a drain, and October is a much better time to learn that than January. Some low spots suit a rain garden or dry well instead, though not in heavy clay. Sustainable Rainwater Solutions for Bay Area Yards covers when each one fits.
Let's Get Your Yard Ready Before the First Storm
If your checklist turns up a problem a hose and an afternoon can’t fix, J&P Landscape can help. We’re a licensed design-build contractor serving San Jose, Silicon Valley, and the Bay Area since 1984, with 40+ years of yards behind us and 12 Best of Houzz awards. Book a free consultation and we’ll walk your yard, find where the water goes, and tell you plainly what it needs. Call (408) 636-6442.
Related Reading: What Counts as an Irrigation Emergency · Before & After Projects
Frequently Asked Questions
At least 4 to 6 feet, and farther in heavy clay. Even better, connect the downspout to a buried pipe that carries water to a safe outlet in the yard.
At least 6 inches of drop over the first 10 feet from the foundation, about a 5% grade. A stake and a string level will check it.
Aim to finish by October. The wet season runs roughly November through March, and December and January are usually the wettest months.
Yes. Clay absorbs water slowly and swells when wet, so runoff stays on the surface. That makes grading, drains, and clear swales matter more than fixes that rely on soaking it in.
Regrading fixes water flowing toward your house from a flat or settled grade. A French drain, a gravel-filled trench with a perforated pipe, suits a low spot that stays wet. A free consultation with J&P Landscape can tell you which one you have.
Yes. We handle yard drainage across the Bay Area, including Cupertino, Los Gatos, Los Altos, Redwood City, Saratoga, Santa Clara, and Sunnyvale. Start with a free consultation.