Mammoth Lakes Excavation Services
In Mammoth Lakes, snow shapes the site plan before the house does. The Town wants room on your lot for the snow you clear. Footings have to get below the frost line. And a trench in a Town street after October 1 needs the Town Engineer’s written approval. Harris Excavation handles excavation, grading, trenching and drainage for Mammoth Lakes homeowners, general contractors and developers, and we lay out the dirt work around all of it from the first site walk.
We’re a licensed California general engineering contractor (CSLB #1117960) and a CA Licensed Timber Operator (#B014361), based in South San Francisco and working across the Eastern Sierra.
Excavation Services for Mammoth Lakes Projects
- Foundation excavation taken below frost and down to the engineer’s bearing elevation. Residential excavation
- Driveway and parking grading with the snow storage area laid out from the start
- Drainage and dry wells sized for snowmelt and roof runoff. Residential drainage
- Utility trenching for water, sewer, storm and electrical service lines. Residential trenching
- Tree removal and fuel reduction for site clearing and defensible space
- Erosion and sediment control set up before the first bucket of dirt moves. Erosion control
Lay Out the Lot for Snow and Snowmelt
The Town’s grading authorization form asks residential projects to set aside snow storage equal to 75% of the required parking and driveway area. The Town’s street standards also say snow removed from a driveway can’t be placed in the right-of-way. So the pile stays on your lot, competing for space with the house and parking.
If a project’s impervious surface will exceed 4,000 square feet, the Town requires a dry well. We grade the driveway, parking and snow storage area so meltwater moves away from the foundation and into the drainage on your plans. No earthwork can begin until interim erosion and sediment control has been inspected and approved, so we install it first.
Footings Below the Frost Line
The Town’s Minimum Design Standards treat the frost line as at least 24 inches below grade, and footings and foundations must extend below it. Those standards also set ground snow loads of 230 pounds per square foot at 8,500 feet or below and 300 above. Soil bearing pressure over 2,000 psf isn’t allowed without a soils report from a licensed engineer or geologist.
We dig to the depths on the plans, keep the subgrade undisturbed, and coordinate with your engineer and concrete crew. The grading form also flags lots sloped more than 30% for a possible engineered grading permit, and asks whether excavation outside the building footprint will exceed 200 cubic yards. We’ll tell you where your project likely falls.
Get Street Work Done Before October
Any work in a Town street or right-of-way, such as a new water or sewer connection, needs an encroachment permit. Trench work scheduled after October 1 requires written approval from the Town Engineer, and paving done after October 15 is treated as temporary unless Public Works approves it. From November 1 through April 30, permission to park or store materials on Town roads can be revoked at any time, and anything in the right-of-way may get buried in snow.
In practice, that means getting your service lines in and the street patched by the end of September.
Trees, Timber Rules and Defensible Space
Clearing a building site here often means removing trees. The Town’s grading form notes that a Timber Harvest Plan or exemption from CAL FIRE may be required when trees are removed. As a Licensed Timber Operator, we can handle tree removal alongside the excavation. Mono County’s 2009 Community Wildfire Protection Plan rated Mammoth Lakes an extreme-hazard community, so defensible space work makes sense while equipment is on site. Our defensible space guide covers the basics.
Where We Work in and Around Mammoth Lakes
We work throughout Mammoth Lakes, including Old Mammoth, Snowcreek, the Knolls, Mammoth Slopes, Sierra Valley Sites, Lodestar and the North Village area. Down US-395 in Bishop, we were brought on in mid-November to trench underslab sewer lines for a new hotel, and had the trenches bedded and ready for pipe before winter arrived (read the project write-up). We also serve June Lake, Crowley Lake, Bridgeport and the rest of Mono County.
Mammoth Lakes Excavation FAQ
How deep do footings need to go in Mammoth Lakes?
The Town treats the frost line as at least 24 inches below grade, and footings must extend below it. Your engineer may call for deeper footings based on the soils and the design.
Where am I supposed to put the snow?
On your lot. The Town asks for snow storage equal to 75% of the required parking and driveway area, and snow from your driveway can’t go into the street right-of-way.
Can you trench in the street in October?
Only with written approval from the Town Engineer. Trench work in the right-of-way scheduled after October 1 needs it, so plan street work for summer.
Do I need a dry well?
You will if your project’s impervious surface exceeds 4,000 square feet. We can excavate and install it with the rest of the site drainage.
Get a Mammoth Lakes Excavation Estimate
Send us your plans, soils report and site survey if you have them. We’ll walk the lot, map out snow storage and drainage, and send a clear written estimate. Request a free estimate