Fill Dirt in Marin County, CA

Fill-dirt is subsoil material (generally low in organic matter) used to raise elevations, backfill trenches, and fill low spots. In Marin County it is commonly used to level yards, build up pads before paving, and as non-structural backfill behind walls; avoid using raw fill-dirt as a finished surface because it may be dusty and compact poorly for driving surfaces.

Costs vary by supplier and exact delivery location, but expect local delivery to range from roughly $10 to $50 per ton once material and hauling are combined, with higher rates for difficult access or long hauls. Hello Gravel has a 3-ton minimum order; some yards add small minimum delivery or drop fees, so get a quote for an accurate all-in price for your zip code and required tonnage.

Fill-dirt density varies, but a common rule is about 1.2–1.5 tons per cubic yard (many projects use ~1.3 tons/yd3). Practical rules of thumb: 100 sq ft covered 1 inch deep = ~0.31 cu yd (~0.4 tons); a 12'x30' area at 6" depth = ~6.7 cu yd (~8.7 tons); raising 1,000 sq ft by 2" = ~6.2 cu yd (~8.0 tons). Use our material calculator or share project dimensions for a precise quote.

For general raising and landscaping, screened, well-graded fill-dirt with minimal organic content is best because it compacts uniformly and settles less. In Marin’s coastal and bay-area soils, avoid organic-rich topsoil for structural fills and consider engineered or compactable fill for slopes or under structures; for drainage-sensitive sites, choose coarser, free-draining fill and pair it with drainage measures.

Small deliveries for routine landscaping often do not require a permit, but larger fills or any work that changes drainage, impacts slopes, wetlands, or creeks usually triggers grading or coastal permits from Marin County. Always check with Marin County Planning and Building or your project engineer before placing large volumes of fill, especially in coastal zones or near waterways.

Loose fill-dirt is prone to erosion and slumping on slopes, especially during Marin’s rainy season, unless it is properly compacted, benched, and protected. For slope work use engineered fill practices, erosion controls (silt fences, blankets, hydroseed), diversion drains, and consider geotextile or retaining structures for steeper sites to reduce washouts and sediment transport to creeks.

Best practice is to place fill in lifts (typically 4–8 inches) and mechanically compact each lift with a plate compactor or roller, with moisture conditioning as needed; this reduces future settlement. Most noticeable settlement occurs in the first weeks to months; for load-bearing or structural areas plan for compaction testing and follow geotechnical recommendations to meet required densities.

Hello Gravel’s minimum order is 3 tons; common delivery trucks in the area are tri-axle dump trucks carrying about 10–15 tons. Some yards may require larger minimums for long-distance hauls or steep access and may charge additional fees for tight access, permits, or offloading assistance, so confirm truck type and any extra charges when you order.

Fill-dirt is intended for raising grade and backfill, not as a finished driveway surface. Road base (compacted crushed rock) is the right choice under a driveway because it provides structural support and drainage; decomposed granite is a good surface material for paths and lighter-drive areas but should be placed over a compacted base. For driveways in Marin’s wet climate use a properly compacted road base with suitable surfacing on top.

Yes. Placing fill-dirt near creeks, wetlands, or coastal areas can increase sediment runoff and harm habitat, and often triggers regulatory review. Use sediment controls, keep stockpiles out of drainways, stabilize disturbed areas promptly, and contact county environmental or permitting authorities before starting work to confirm setback and permit requirements.