Sonoma County · Winter Storm Readiness · CA LIC #1060838
Is Your Sonoma County Property Ready for This Winter's Storms?
Sonoma County's clay soil holds water instead of draining it, which is exactly what turns a heavy rain event into flooding, hillside erosion, or a washed-out driveway. With a strong storm season on the way, DW Excavation is helping Sonoma County property owners get ahead of it — before the ground gets saturated.
Before the ground saturates
Schedule a Storm Readiness Assessment
We'll look at your drainage, slopes, and access points and tell you what needs attention before the rain starts.
707-601-9091 Or send us a message →CA LIC #1060838 · Licensed & Insured · Based in Windsor
Clay Soil Holds Water — It Doesn't Drain It
In November 2024, an atmospheric river dropped over 12 inches of rain on Santa Rosa in just three days. Properties across Santa Rosa, Windsor, Healdsburg, Petaluma, Rohnert Park, and the surrounding unincorporated areas dealt with flooded yards, eroded slopes, and washed-out driveways — a reminder of how quickly Sonoma County's clay soil turns a heavy storm into real damage.
We've been doing site work in Sonoma County since 2013, and if there's one thing our team has learned firsthand, it's that clay soil and heavy rain don't mix well. Water sits instead of soaking in, hillsides lose their grip, and low spots turn into standing water fast. With a strong storm pattern expected again this winter, we're encouraging property owners to take a look at their drainage, slopes, and access points now, before the rain starts.
Santa Rosa · November 2024
Get Your Property Ready — By Service
Drainage Solutions & Stormwater Management
Sonoma County's clay soil is the root of most of the flooding problems we see. Because it drains so slowly, water that would soak into sandier soil elsewhere tends to pool, run toward foundations, or overwhelm yards that don't have a clear path for it to go. A few things worth checking before the rain starts:
- Standing water in the yard more than a day after rain
- Downspouts that dump water right next to the foundation
- Low spots or drainage paths that have never been properly graded
We design and install drainage systems — French drains, grading, catch basins, and stormwater management — built for how Sonoma's soil actually behaves, not a generic drainage plan.
Water Management →Erosion Control & Hillside/Slope Stabilization
Saturated clay loses its structure fast, which is why hillside and slope properties across Sonoma County are especially exposed during a strong storm season. A slope that's held steady for years can start moving after a few days of heavy rain if it hasn't been evaluated.
Our team looks at slope stability, drainage patterns, and vegetation to identify where erosion is likely to start, and puts erosion control measures in place — retaining structures, regrading, or drainage rerouting — before it becomes a bigger problem.
Erosion Control →Flood Cleanup & Site Recovery
When flooding does happen, getting a property properly cleared and regraded matters just as much as the initial drainage fix — standing water and displaced soil left behind can set up the same problem for the next storm.
We handle flood cleanup and site recovery, including removing displaced soil and debris, regrading affected areas, and rebuilding drainage that failed the first time around.
Excavation Services →Driveway & Access Road Washout Repair
A washed-out driveway or access road is one of the most common calls we get after a heavy storm — and one of the most disruptive, since it can cut off vehicle access to a property entirely.
We repair and regrade washed-out driveways and access roads, and where it makes sense, rebuild them with better drainage so the same washout doesn't happen again next season.
Grading Services →
Why DW Excavation
DW Excavation, LLC is a licensed California general engineering contractor (CA LIC #1060838) based in Windsor, founded by Dallas Wohlfeil in 2013. We've spent over a decade working directly in Sonoma County's clay soils, so storm and drainage work here isn't guesswork — it's the majority of what we do. When you call, you're talking with the team that will actually be on site, not a dispatcher.
- CA LIC #1060838
- Established 2013
- Based in Windsor
- Owner-Operated
Where We Work
We serve Santa Rosa, Windsor, Healdsburg, Petaluma, Rohnert Park, and the surrounding unincorporated areas of Sonoma County. Storm and flood work is part of the broader site work we do across the county — see our Sonoma County service area page for the full scope.
Storm & Flood FAQ
Questions we hear most often from Sonoma County property owners heading into a wet winter.
📞 Still have questions?Call us directly
Why does my yard flood every time it rains hard? +
In most cases it comes down to Sonoma County's clay soil, which drains far slower than sandier soil types. Without proper grading or a drainage system in place, water has nowhere to go and pools in low spots or near the foundation.
Do I need a permit for grading or drainage work in Sonoma County? +
Sonoma County requires a grading permit for any cut or fill over 50 cubic yards. We handle permit questions as part of our process so projects don't get held up.
How do I know if my slope or hillside is at risk? +
Warning signs include cracks in the soil, leaning trees or fence posts, and water pooling at the base of the slope after rain. If you're seeing any of these, it's worth having it looked at before the next storm.
What does flood cleanup and site recovery involve? +
It typically includes removing displaced soil and debris, regrading affected areas, and repairing or rebuilding drainage that didn't hold up during the storm.
What areas do you serve? +
We serve Santa Rosa, Windsor, Healdsburg, Petaluma, Rohnert Park, and the surrounding unincorporated areas of Sonoma County.
What should I do if my driveway or access road washed out? +
Contact us directly at 707-601-9091 — we can assess the damage and repair or regrade the area, often improving the drainage so it holds up better next time.
Get Ahead of
This Winter.
Sonoma County's storm seasons don't wait for anyone to be ready. If you'd like a second set of eyes on your drainage, slopes, or access points before this winter, contact DW Excavation at 707-601-9091 or through our contact page.