Kenmore · King County
Grading & Drainage in Kenmore, WA
Grading, French drains, retaining walls and RV and equipment pads across Kenmore, from Kenmore and the north end of Lake Washington. Built so water moves away from the house instead of toward it.
Why drainage matters on Kenmore properties
Glacial till and outwash on the slopes, with soft, wet lake and river deposits along the shoreline. That is the root of most wet-yard, wet-crawlspace and failing-patio problems we see. Water that cannot soak in runs along the surface or perches on the hard layer until it finds the lowest point.
A narrow flat strip along the lake and river, with steep wooded slopes rising north and east into neighborhoods like Inglewood and Moorlands. Slopes push water downhill onto the next lot, and flat ground leaves it nowhere to go. Getting the grade right is cheaper than fixing what water does to a foundation.
Lake Washington shoreline, the Sammamish River, Swamp Creek and Little Swamp Creek carry shoreline and stream buffers. Many slopes are mapped critical areas. Where drainage can legally discharge depends on these features, so we plan the outlet first and the trench second.
Common grading projects in Kenmore
Wet yards and crawlspaces
Regrading and French or curtain drains for Kenmore yards that stay soggy all winter because water perches on the hard till below.
Retaining walls on slopes
Block and rock retaining walls that hold back sloped Kenmore yards and driveways, built with drainage behind them so they last.
Grading away from the foundation
Reshaping the ground around Kenmore homes in Downtown Kenmore and Inglewood so it falls away from the house, the cheapest fix for water at the foundation.
Ditches and culverts
Cleaning and regrading drainage ditches, and setting culverts under driveways, on the low, wet ground around Kenmore.
Downspout tightlines
Connecting downspouts to solid pipe that carries roof water to an approved outlet instead of dumping it next to a Kenmore foundation.
What our grading work in Kenmore covers
- Retaining Walls
- French Drains & Footing Drains
- Rough & Finish Grading
- RV & Equipment Pads
- Yard Drainage Correction
- Erosion Control
Permits & Rules
Grading and retaining wall permits in Kenmore
Inside city limits, the City of Kenmore handles grading permits; outside them, the King County Department of Local Services. Small regrading and yard drains usually do not need one, but larger volumes of cut or fill, work in a critical area, or changes to how water leaves the property often do.
Retaining walls taller than about four feet, or walls holding back a driveway or slope, typically need engineering and a permit. We build to the approved plan and can tell you on the site walk when a wall is likely to need one.
Cost & Timing
What affects the cost of grading in Kenmore
We do not publish flat prices because no two Kenmore sites are the same. These are the things that move the number most here.
Slope and access
Steep Kenmore lots take smaller machines, more careful staging and sometimes engineering, which adds time compared with flat, open ground.
Soft ground
Where Kenmore soils are soft or wet, over-excavation, fabric and imported rock are often part of the job, and we price that in up front.
Buffers and permits
Work near Kenmore's rivers, creeks, lakes or shoreline can need permits and limits on where machines go. That affects scope and schedule more than price.
Haul-off and disposal
How much material leaves the site, and what it is, drives cost. Our own trucks keep that predictable on Kenmore jobs.
When to schedule grading in Kenmore
Grading in Kenmore goes best in the drier months, when soil compacts properly and trenches stay open. Wet-season work is doable with erosion control and the right material, and we plan for it in the quote.
Kenmore's till soils hold water through the winter, which is when drainage problems show up. That is a good time to see where water goes, and the dry season is the time to fix it.
Where We Work
Grading and drainage across Kenmore
Kenmore sits at the north end of Lake Washington where the Sammamish River enters it. Much of the city is steep, wooded hillside above the lake and the Burke-Gilman Trail.
We regrade yards, install French drains and curtain drains, build block and rock retaining walls, and set gravel RV and equipment pads across Downtown Kenmore, Inglewood, Moorlands, Arrowhead, Uplands and Northshore Summit.
Mostly 1950s to 80s homes on sloped, wooded lots, with newer infill and redevelopment near downtown. Older lots often have no real drainage at all, while newer ones sometimes have drains that were never connected. We find out which before we dig.
We also do grading nearby in Lake Forest Park, Bothell, Brier and Mountlake Terrace. See everything we do in Kenmore, read our full guide to grading, or browse all service areas.
Why DirtRaptor
Why Kenmore owners call us for grading
Owner on the machine
On Kenmore jobs you talk to the person who walks the site, writes the quote and runs the equipment.
Trees and dirt, one crew
If trees are in the way of your Kenmore project, we take them down ourselves instead of waiting on a separate tree service.
Our own trucks
Haul-off and deliveries run on our schedule along SR 522 (Bothell Way) and Juanita Dr NE, not a subcontractor's.
Built for slopes
We plan machine placement, drainage and erosion control for Kenmore's sloped ground before we start.
How a grading job runs
- 01
Site Assessment & Water Tracing
- 02
Design & Elevations
- 03
Excavation & Base Preparation
- 04
Build, Drainage & Backfill
Real Jobs
Recent DirtRaptor work near Kenmore
Demolition · Edmonds, WA
Driveway Removal & Concrete Prep
Tearing out an old blacktop driveway and prepping the ground for a new concrete pour — broken material hauled off, base left clean and ready.
Demolition · Everett, WA
Condemned 100-Year-Old Shed Teardown
A 100-year-old shed, condemned and unsafe, brought down and hauled off — the site left graded flat and clean.
Questions
Grading & Drainage in Kenmore: FAQs
Why does water collect around homes in Kenmore?
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Glacial till and outwash on the slopes, with soft, wet lake and river deposits along the shoreline. When water cannot soak in, it follows the surface toward the house. Regrading so the ground falls away from the foundation, plus a drain where needed, usually solves it.
Do retaining walls need a permit in Kenmore?
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Walls over about four feet, or walls supporting a driveway, building or slope, usually need engineering and a permit from the City of Kenmore (or the King County Department of Local Services outside city limits). Shorter landscape walls often do not. We confirm before building.
Where can drainage water go on my Kenmore property?
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It has to go somewhere approved: an existing storm system, a dispersion area or an infiltration trench where the soil allows. Lake Washington shoreline, the Sammamish River, Swamp Creek and Little Swamp Creek carry shoreline and stream buffers. Many slopes are mapped critical areas. We plan the outlet before we trench.
How much does grading cost in Kenmore?
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It depends on the site, so we quote after a free site walk rather than guessing on the phone. The biggest drivers in Kenmore are usually slope and access, soft ground, buffers and permits. You get a written number with inclusions and exclusions spelled out.
When is the best time to schedule grading in Kenmore?
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Grading in Kenmore goes best in the drier months, when soil compacts properly and trenches stay open. Wet-season work is doable with erosion control and the right material, and we plan for it in the quote.
Can you remove a tree above my Kenmore house on a steep slope?
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Yes. On slopes we usually take trees down in sections and leave stumps and roots in the ground to hold the soil. If the slope is a mapped critical area, we flag what review is needed.
Do you work along the Kenmore shoreline?
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Yes, within the shoreline rules. Work near the lake or river can need approval, so we check before starting.
How much does a retaining wall cost per foot?
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Face square foot is the usual unit, but cost per foot rises steeply with height because the work behind the wall grows faster than the wall itself. A two-foot garden wall and a five-foot structural wall are different trades. Site access and drainage requirements move it further.
Ready for a real number in Kenmore?
Send the address and a few photos. We walk the site for free and come back with a written quote.
