Granite Falls takes the mountain rain and sits on ground that falls away toward the river and the falls. Steep sides of lots are normal. Water concentrates, finds the weak spot in a bank, and leaves a rill where the lawn used to be. Foothill banks want mass. A light stack will walk down the hill the first winter the seep gets behind it.
Snohomish County · ZIP 98252 · 2020 population 3,572
This is the ground rock walls are for
We use large base stones, a batter back into the hill, and drain rock in the voids so the wall is not holding a lake. The face stone is local and irregular. A cut bank above a drive is structural, and if the height needs an engineer we stop and get one instead of adding another course.
Machine access is the limit. If the driveway cannot take the truck, the wall gets smaller or it gets built from stone we can actually place. We will not design a quarry face we cannot deliver.
The ground in Granite Falls
Properties on the edge of town back into fir and alder. The lawn, if there is one, is a cleared bench. The rest is slope, stump, and shade. We get called when a bank has started to slump after a wet winter, or when a path down to the lower yard has turned into a creek.
Rock walls and a drain at the top of the slope do more than plants will. Beauty bark in the deep shade keeps the weeds down and the mud off the house, but it will not hold a bank by itself. Tree work is practical: limbs over the roof, and sightlines where the forest is closing the drive. Aerator and seed belong on the flat piece only. Treating the whole hillside like a turf job is how you waste a season.
How we do the work
A rock wall is dry-stacked or lightly set, with the weight in the stone and the drainage in the voids. It is not a veneer glued to a failing timber wall. We use rock big enough for the height, with a face that leans back into the hill, and smaller rock locked behind so the soil does not pipe through.
Good rock work looks heavier at the bottom. If every stone is the same patio-sized block, it is not a wall, it is a stack. We source local stone and we will tell you when the access cannot take the boulder the job wants.
What we look at first
- Height and whether it is structural or a garden edge
- Machine access for real boulders
- The soil behind: clay that needs a drain, or rock that already sheds
- An existing wall we are tying into
The base course
The biggest stones, buried, on compacted rock or competent ground. If the first course is the one you can see sitting on the grass, the wall is already failing. You should see the second course at grade, not the bottom of the first.
Dry stack versus mortared
Most of our rock walls are dry, so water can leave and the wall can move a little without cracking a joint. Mortar is for a low, formal edge that is not holding a wet hill. We do not mortar a drainage problem shut.
What it will not do
A rock wall will not hold an engineered height it was not built for, and it will not stop a landslide. Past a certain height we involve an engineer or we change the grade so the wall can be shorter. That conversation happens before the stone is ordered.
More from this crew
- Rock walls across Snohomish County
- Retaining walls in Granite Falls
- Gravel installation in Granite Falls
- Landscaping in Granite Falls
- Hardscaping in Granite Falls
- Rock walls in Arlington
- Rock walls in Lake Stevens
- Rock walls in Marysville
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.
