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DRAINAGE · WINTER-READY · HILLSIDE
Give the water somewhere to go.
Every atmospheric-river winter, the same SF garages flood, the same crawl spaces go swampy, and the same retaining walls start leaning — because the water was never given a path. French drains, area drains, and sub-surface systems are that path, and building them is concrete-adjacent work we do year-round.
- FREE ON-SITE ESTIMATES
- LICENSED & INSURED
- PERMITS & INSPECTIONS HANDLED
SCOPE OF WORK
Drainage systems we build
The design question is always the same: where does the water come from, and where is it legally allowed to end up?
French drains
Trenched, fabric-lined gravel drains with perforated pipe, placed where the water actually travels — along uphill property lines, behind walls, at the base of slopes — and routed to an approved discharge.
Area & channel drains
Catch basins in ponding low spots and channel drains across driveway and garage thresholds — the difference between a wet street and a wet garage.
Wall & foundation drainage
Drainage as part of retaining wall and foundation scopes: back-of-wall systems, footing drains, and sub-slab drainage for dig-downs. Built in, not bolted on.
SITE CONDITIONS · WHERE SF WATER GOES
SF drainage has one weird rule
San Francisco runs on a combined sewer — storm runoff and sewage share the same system. Where your drain is allowed to discharge is a design constraint, not an afterthought.
≈ Storms come in trains now
Recent SF winters have stacked atmospheric rivers back to back — soil saturates in the first storm, and every storm after that runs off like the ground is pavement. Systems sized for an average rain fail in week two of a wet January.
We size for the stacked-storm winter, with cleanouts so the system can be maintained instead of replaced.
§ Discharge is regulated
You can’t aim collected water at your downhill neighbor, and connections to the city system have rules. Legal discharge — to an approved point, with the right air gaps or backwater protection — is part of the design we quote.
On flat west-side lots without gravity fall, that can mean a sump and pump; we’ll tell you upfront rather than trench first and discover it.
△ Drainage saves the expensive stuff
Most of the failed retaining walls and settled foundations we’re called to repair are drainage failures wearing a concrete costume. A drainage system costs a fraction of the wall or foundation it protects.
That’s why every wall and dig-down we build includes drainage — and why we build stand-alone systems before yours becomes a repair customer.
COMMON QUESTIONS
Drainage questions, answered straight
French drain or area drain — which do I need?
When should drainage work be done?
Will a French drain stop my garage from flooding?
Do drains need maintenance?
NO-COST · NO-PRESSURE
Get your free estimate
Tell us what’s cracking, settling, or waiting to be built. We’ll walk the site, measure it, and hand you a written price — free, and good whether you hire us or not.
Call now — (415) 687-3728