Gravel Delivery in California

The Central Valley is built of river deposits. The state geologic map lists coarse alluvium and fine alluvium at the center points of both Sacramento and Fresno. Alluvium is sand, gravel, silt and clay laid down by rivers. The coarse kind is mostly sand and gravel, and the fine kind is mostly silt and clay. River deposits like these are where much of California's sand and rounded gravel is dug, which is why washed River Rock, Pea Gravel and Concrete Sand are common stock in valley towns such as Stockton, Modesto, Visalia and Bakersfield.^[1]

The surface soils vary along the coast and the bay. The USDA survey reads sandy loam at the center point of Los Angeles and classes it somewhat poorly drained. San Jose's center point reads clay loam, well drained. Oakland's reads loam, moderately well drained, and Fresno's also reads loam, moderately well drained. Clay loam packs hard and swells a little when soaked. Sandy loam is loose and easy to dig, but a somewhat poorly drained class means water can sit in it for a while after a long rain.^[2]

Most of the big cities sit close to sea level. The ground at San Diego's center point is at 0 feet. Sacramento's and Long Beach's center points are each at 20 feet, Oakland's at 40 feet, San Francisco's at 50 feet and San Jose's at 80 feet. Los Angeles stands at 150 feet at its center point and Fresno at 350 feet. Flat ground near the coast and the Delta can be slow to shed water after a winter storm, so drainage plans matter even in a dry state.^[3]

Caltrans spells out its requirements for the layer under state highways in Class 2 Aggregate Base, Section 26-1.02B, Standard Specifications (2026). Contractors across the state often use the phrase Class 2 when they mean a dense, crushed base mix. For a home job, ask for Road Base or Crushed Concrete when you need a layer that packs hard under a drive, a patio or a shed.^[4]

Rain comes mostly in winter, and the totals vary a lot. The weather station used for San Francisco averages 22.9 inches of precipitation a year and Oakland's 22.6 inches. Sacramento's station averages 19.2 inches and San Jose's 16.1 inches. Los Angeles averages 14.2 inches at its station, Long Beach 12.0 inches, Fresno 11.0 inches and San Diego 9.8 inches. In the dry months a yard is firm almost anywhere. After a string of winter storms, lawns over clay or sandy loam can stay soft for days.^[5]

Freezing nights are rare in the large cities. The stations for Los Angeles, San Diego, San Francisco, Oakland and Long Beach each log 0 days a year at 32 F or colder. San Jose's station logs 2 days and Sacramento's 4 days. Fresno's station logs 11 days, the most in this group. Snow averages 0.0 inches at the stations for San Jose, Sacramento, Oakland and Fresno. Frost heave is not a factor for a gravel drive in these cities. Inland towns such as Palmdale, Lancaster and Chico can see colder nights.^[5]

Access shapes most city drops. Many lots in San Francisco, Oakland and Berkeley are narrow and steep, with no driveway that a dump truck can use. In those places a load usually goes at the curb where that is allowed, so plan for help to move it soon after it lands. Suburban drives in places like Elk Grove, Roseville or Temecula are easier, but overhead lines, trees and tight cul-de-sacs still limit where a bed can rise.^[3]

Keep loose material out of the storm drain. Rain and hoses carry sand, soil and mulch from a curb pile into the gutter. Put the pile on a tarp, sweep up after moving it, and cover soil and mulch if a storm is in the forecast. On the somewhat poorly drained sandy loam mapped at Los Angeles's center point, a lawn can be soft after winter rain, so a hard surface is the safer spot for a heavy truck.^[2]

Water-wise yards are the most common California project. Many owners replace lawn with stone and drought tolerant plants. Decomposed Granite makes firm paths and seating areas. River Rock and Pea Gravel fill beds and dry creek beds. #57 Crushed Stone and 3/8" Crushed Stone give a tidy, modern look around succulents. Lay weed fabric under decorative stone, and add Compost to the planting holes, since new plants still need good soil to root.^[2]

Driveways and parking pads follow. On clay loam like the survey maps at San Jose's center point, pack Road Base or Crushed Concrete in thin lifts, wetting each lift so the fines bind. Top it with Driveway Gravel, Decomposed Granite or 3/4" Crushed Stone. For a long rural drive in the valley, Asphalt Millings give a firm, dark surface that tightens up in summer heat. A slight crown sheds the winter rain.^[2]

Drainage matters most in the wetter north and on low ground. With 22.9 inches of yearly precipitation at San Francisco's station, roof water and paved areas can flood a side yard in a storm. A French drain lined with fabric and filled with Drain Rock or #57 Crushed Stone carries water away. A bed of River Rock under a roof edge with no gutter keeps soil from splashing onto walls.^[5]

Patios, paths and pool areas fill out much of the rest. Pavers sit on packed Road Base with a thin, level bed of Concrete Sand or Stone Dust Screenings. Mason Sand fills the joints between bricks and flagstone. Pea Gravel around a pool or a fire pit drains quickly and stays comfortable underfoot. Walkway Gravel between steel edging is a simple path that drains on its own.^[2]

Garden beds and orchards in the valley do well with added organic matter. The loam mapped at the center points of Fresno and Oakland is a good start, and a layer of Compost or Garden Soil worked into the top helps it hold water through a dry summer. Brown Shredded Mulch, Red Mulch or Wood Chips over the root zone cut evaporation and keep weeds down. Topsoil builds up raised beds and fills low spots in a lawn.^[2]

Hillside yards in places like Thousand Oaks, Oakland and San Mateo need slope care. Riprap and larger River Rock armor a swale or a bank where runoff gathers. A low wall of blocks backed by #57 Crushed Stone holds a terrace, and Wood Chips or shredded mulch on bare slopes slow erosion while new plants take hold.^[2]