Serving the Cowichan Valley
Excavation and site work around Shawnigan Lake
Shallow bedrock, a drinking-water lake, and a community with good reason to ask where fill came from.
Free, no-obligation quote
Excavation quote request
The more detail about the property and the work, the closer the first number will be. We send a written quote after we visit your site.
Duncan Excavating works around Shawnigan Lake in the Cowichan Valley Regional District, where bedrock outcrops sit east and west of the lake with cover under 5 metres or absent. Because local households draw drinking water from the lake, we include sediment control and check where fill came from before bringing soil onto your lot.
Two questions come up on almost every Shawnigan Lake job: what's actually under the topsoil, given how close bedrock sits here, and where the material is coming from — or going to.
Rock is the main variable. Bedrock crops out on both sides of Shawnigan Lake under soil cover that is typically under 5 metres thick or absent. If we hit solid rock on your dig, we use a hydraulic breaker rather than a standard bucket.
Rock, and how close to the surface it is
Provincial mapping shows solid bedrock exposed or sitting right under a thin layer of soil along the eastern and western sides of Shawnigan Lake. Soil cover reaches up to 30 metres in isolated spots on the east side, but across most lots it measures less than 5 metres thick or disappears entirely. Water-bearing fractures in the bedrock sit at a median of around 80 metres. Whether a footing or a trench hits rock is decided on your lot, so we establish your site conditions before we book a machine.
Why fill origin matters around the lake
Local households around Shawnigan Lake draw their drinking water directly from the lake. So we can tell you where any imported fill came from and where your excavated material is going, and we expect to be asked. Because a contaminated-soil landfill operated at a Stebbings Road quarry from 2013 until its closure in 2020, we verify that all clean fill brought to your lot comes from approved clean sources.
When the bucket hits rock
When a standard bucket strikes solid bedrock, pulling or scraping will not move the ledge. Continuing to force a digging bucket against hard rock damages equipment without making progress on your excavation.
We stop digging and assess the rock surface exposed in the trench or footing hole. If the rock needs to come out, we switch tools to a hydraulic breaker mounted on a machine. The breaker uses rapid heavy impacts to fracture the stone into manageable pieces. Once the rock is broken into chunks, we swap back to a bucket to scoop out the rubble. Breaking rock takes extra time and specific attachment equipment, so we adjust the work sequence to keep your project moving efficiently.
Getting your lot ready for us
A little preparation before the machine arrives helps your site work go smoothly. Clear cars, trailers, and stored materials away from your driveway and access routes so transport trucks can back in safely.
Mark any hidden property features you want protected. Low branches along the access path should be trimmed back to clear high machinery cabs. Move garden hoses, decorative stones, or portable structures away from the work area. Keep pets indoors and make sure children stay well clear of the machine operating zone. If you have underground lines that utility locates do not cover, such as private irrigation or septic runs, mark those paths clearly with stakes or spray paint before we begin.
We'll answer the rock question for your Shawnigan Lake project as soon as you request a quote and we get a look at the site.
Excavation services
- Footings and FoundationsWe handle foundation digging and footings in Duncan, cutting strictly to surveyor's levels and planning around the winter water table on every new build.
- Perimeter Drains and DitchingWe install perimeter drains, foundation drainage, and water and sewer service trenching in the Cowichan Valley, where groundwater medians sit at 2.4 metres.
Nearby service areas
Ready for a quote on excavation in Duncan?
We quote excavation across the Cowichan Valley after a site visit.