Sultan sits on the Sultan River, on the way up the highway toward the trails and the passes. Yards step with the terrain. Water comes off the higher ground, crosses a lawn, and heads for the river or the ditch. On a hillside the drain belongs above the lawn and above the wall, where the water is still concentrated. A drain at the bottom is a mop.
Snohomish County · ZIP 98294 · 2020 population 5,458
Intercept the water at the top of the slope
We cut a line across the slope, deep enough to catch the seep, and we outlet it to the side, not down the middle of the yard. The pipe has to be protected from the rock and the fill that move every winter. Cleanouts go in where a mountain silt load will eventually arrive.
A French drain is not a retaining wall. If the bank is moving, the wall comes first or with it. Pipe alone in a slumping cut just becomes a crushed pipe.
The ground in Sultan
The useful projects are the ones that make a sloped lot walkable: a gravel path that stays put, a rock wall where the bank is cutting, a drain at the top of the slope so the patio is not the creek. Forest edge is close. Alders and maples lean in, and after a wind the cleanup is limbs, not a few leaves on a patio.
Lawns exist on the benches. They need seed that can take shade at the tree line and a soil that is often thin. We do not promise a golf-course surface against the timber. Native mountain plants hold the cuts better than a bark bed that just slides downhill in January. Access for machines is usually fine along the highway side and tight once you are in the trees. We look at that before we promise a wall.
How we do the work
A French drain is a perforated pipe in washed rock, wrapped so the fines do not fill it, sloped to a place the water can actually leave. We do not end a drain in a dry well of hope, and we do not outlet it at the neighbor’s shed.
The trench is deep enough to catch the water you are chasing, which is often the downspout and the wet line along the foundation, not a decorative strip in the middle of the lawn. Surface grading still matters. A drain cannot fix a patio that pitches at the house.
What we look at first
- Where the water shows up, and where it can daylight
- Downspouts that are dumping at the footing
- Utilities before we trench
- Whether the wet spot is a seep that will need more than one line
Cost follows the outlet
A short line with an easy daylight is a different job from a line that has to cross a drive, miss a gas service, and reach a ditch fifty feet away. We price it after we see the outlet. We do not quote a per-foot number from the curb.
What the trench looks like
Fabric, washed rock, pipe with the holes oriented the way the detail calls for, then rock, then fabric closed, then soil. The lawn or the bark goes back on top. A trench of pit-run gravel with a pipe tossed in will silt up, and we do not build those.
Downspouts
Solid pipe until it is away from the house, then into the drain if the drain can take the roof. We do not dump a whole roof into a two-inch pop-up in the middle of the lawn and call it drainage.
More from this crew
- French drain installation across Snohomish County
- Retaining walls in Sultan
- Gravel installation in Sultan
- Landscaping in Sultan
- Patio installation in Sultan
- French drain installation in Monroe
- French drain installation in Gold Bar
- French drain installation in Index
Sources for the climate and the water
- USDA plant hardiness map for choosing plants that can take a Snohomish County winter.
- EPA WaterSense on watering less once a lawn or a new planting is established.
- EPA Soak Up the Rain on keeping roof and yard water from becoming someone else’s problem.



