Gutters, Downspouts and Yard Drainage: A Pre-Rainy-Season Checklist
Drainage is the least glamorous part of a house and the one that decides whether storm water goes past your home or into it.
Clear gutters, then test every downspout and area drain with a hose rather than judging by the grate — they silt up invisibly under bark mulch. Confirm downspouts discharge well away from the foundation, and check that grading still falls away from the house. Decades of planting beds building up is the most common reason a yard that used to drain no longer does.
When storm water gets into a Southern California house, the cause is almost never the building. It is almost always drainage that could not cope, usually because something was blocked.
This is the pre-season routine, and the permanent fixes worth making if the same thing keeps happening.
Gutters: clear, aligned, fixed
- Clear the full length including the corners, where debris compacts hardest.
- Flush with a hose and watch that water actually reaches the downspout rather than pooling.
- Check the fall. A gutter that has sagged holds standing water, which adds weight and eventually pulls the brackets out.
- Check the fixings. Loose brackets fail under the weight of a full gutter in heavy rain.
- Look for tile fragments and granules in the gutter — a good early warning that the roof has taken wind damage.
Downspouts: where the water actually ends up
A clear gutter that discharges against the foundation has simply concentrated the roof’s entire catchment at one point on your wall. In Mission Viejo, where soil against the slab edge is frequently already raised by decades of planter build-up, that is a direct route into the wall base.
Check where each downspout discharges. Extend anything that dumps within a few feet of the wall, either with a surface extension or into a buried drain that discharges to the street or a proper outlet. Then verify that any buried line is actually clear by running a hose into it and watching the outlet.
Yard and area drains
- Lift every grate. Mature planting hides them and bark mulch fills them.
- Clear the basin below the grate, not just the surface debris.
- Run a hose into each one and confirm flow at the outlet. A drain that takes water at the grate can still be blocked six feet downstream.
- Check patio drains specifically — a blocked one backs up over a threshold with startling speed.
- Map where each drain actually discharges. A surprising number of homeowners have no idea.
Grade: the fix nobody thinks about
Walk the perimeter and look at where the ground meets the wall. It should fall away from the house — a few inches of drop over the first several feet.
On homes of Mission Viejo’s vintage, this is frequently no longer true. Forty years of mulch top-ups, raised planter beds, new hardscape and landscape changes gradually build soil up against the wall, sometimes above the slab edge. At that point water sitting against the house has a direct path into the wall base.
Correcting it means removing built-up soil and re-establishing fall. It is unglamorous, it is cheap, and it permanently fixes a class of problem that no amount of drainage clearing will.
Hillside and slope-below properties
If you are below graded slope or open terrain, add the drainage that sits above you: terrace drains, brow ditches and swales. These are the first line of defence and they are the ones nobody inspects because they are up a bank.
Note whether terrain above you has burned in recent years. Burned slopes shed water instead of absorbing it and carry ash and sediment with it, for several seasons afterward. That changes what an ordinary storm can do and it is worth taking seriously.
Where common-area drainage above your lot is the association’s responsibility, raise concerns in writing before the season rather than after an incident.
Permanent fixes when the same thing keeps happening
- A French drain or trench drain across the path water repeatedly takes.
- A diversion swale to route runoff around the building rather than to it.
- Re-grading a side yard or patio that falls toward the house.
- Raising a threshold, or fitting a removable threshold dam at the slider that takes water.
- A channel drain across a driveway that slopes toward the garage.
- Additional area drains where the existing ones are simply undersized for what arrives.
Watch it happen
The single most useful diagnostic is free. During the next heavy rain, put a coat on and walk the perimeter of your property.
Where does water pool? Which drain is not taking it? Where is it running? Where does it get within a foot of a door or a wall?
Ten minutes of that tells you more about your specific risk than any checklist, and it tells you exactly which of the permanent fixes above would actually help.
Frequently asked
How often should I clear the drains?
Everything before the season in October, and gutters again mid-season if there has been significant leaf fall. Any drain under a tree deserves a second check.
Are gutter guards worth it?
They reduce how often you clear gutters; they do not eliminate maintenance, and some types trap fine debris that then compacts. Useful under heavy tree cover, not a substitute for looking.
Storm water got in despite clear drains. What now?
Then the drainage is undersized or the grade is wrong for what arrives, and it needs a design fix rather than more maintenance. Watch where the water goes in the next storm, then address that specific path — a swale, a trench drain, or re-grading.
Expert insight
The drain nobody tests
On the great majority of storm-intrusion calls we attend in Mission Viejo, the cause is a silted area drain in a side yard that looked perfectly fine from above. The grate is clear; the pipe below is not. Twenty minutes with a hose in October tells you which of your drains actually work, and it is the single highest-value maintenance task on this list.
The bottom line
Clear everything, check where it discharges, fix the grade against the house, and watch your property in the next storm.
It is the cheapest insurance available against the losses we clean up every January.