Gravel Delivery in Hawaii

Honolulu is the one Hawaii city on our delivery list. The ground at its center point stands 730 feet above sea level. That is the height of one spot, not of every yard in the city. Lots near the shore sit far lower than that, and lots up a ridge may sit higher, so it pays to look at your own grade and where water runs on it before you choose a stone.^[1]

The Hawaii Department of Transportation spells out what it wants beneath its roads in Aggregate Base Course, Section 304, of its Standard Specifications for Road and Bridge Construction (2005). That document is written for highway crews. A homeowner needs only a few plain ideas about stone to choose well, and they start with how a load is made.^[2]

Crushed stone comes from solid rock that is blasted, broken and screened into sizes. The pieces have sharp faces and corners, so they lock against each other when packed. #4 Crushed Stone and 1-1/2" Crushed Gravel are the large sizes, used as a first layer on soft ground. #57 Crushed Stone and 3/4" Crushed Stone sit in the middle and do most of the work in drives and drains. #89 Crushed Stone and 3/8" Crushed Stone are small chips for walks and for setting pavers.^[1]

Rounded stone forms when water tumbles rock for a long time. River Rock and Pea Gravel have smooth faces and no sharp edges, which makes them pleasant to look at and to walk on barefoot. The same smooth faces let them roll past each other under weight, so they stay out of any base layer. With 151.0 inches of yearly precipitation at the station used for Honolulu, a round stone that drains freely belongs in a bed or a border.^[3]

Some materials in a load are mixes rather than pure stone. Road Base and Driveway Gravel blend crushed stone with fines, the small grains and dust that fill gaps and set up hard once compacted. Stone Dust Screenings are the fines on their own. Crushed Concrete and Asphalt Millings are recycled from old pavement, and each packs into a firm surface. Sand comes in grades: Concrete Sand is coarse, Mason Sand is fine and even, Fill Sand is for bulk filling, and Playground Sand is washed soft for children.^[2]

Water is the main thing to plan around. The station that reports for Honolulu averages 151.0 inches of precipitation a year, which is a large amount even by tropical standards. Ground that has just taken a heavy shower may be too soft for a loaded truck, and a sand or mulch pile left in the open will soak up water and wash at the edges. Have a tarp ready to cover the pile until you can spread it.^[3]

Cold plays no part. The same station logs 0 days a year at 32 F or colder and averages 0.0 inches of snow. Frost heave, the lifting that breaks up gravel drives on the mainland, does not happen here. That leaves water, runoff and soft ground as the forces a Honolulu driveway or path has to resist, and it lets you spread stone in any month of the year.^[3]

Pick the drop spot with care. A paved driveway or a carport slab is the best place for a load. Lawns soaked by frequent rain can rut deeply under a heavy truck. Keep the pile away from storm drains and from the low edge of the lot, where runoff gathers. If your lot slopes, tell us which way, since a driver needs a level place to raise the bed and tip the load safely.^[3]

Check the route in. Narrow lanes, tight turns, low tree limbs, overhead lines and carport roofs can all limit where a truck can go. A raised dump bed needs plenty of open space above it. Measure your gate and driveway width if they look tight. On a hillside lot, the driver may tip the load near the street, and you can move it the rest of the way with a wheelbarrow.^[1]

Drainage tends to be the first project in a place this wet. With 151.0 inches of yearly precipitation at the station used for Honolulu, roof runoff and yard puddles show up fast. A French drain lined with fabric and filled with Drain Rock or #57 Crushed Stone carries water away from a wall. A dry well of the same clean stone takes the flow from a downspout. Riprap protects a bank or a pipe outlet from scouring.^[3]

Gravel driveways and parking pads come next. A firm drive starts with the soil graded so water runs off, then fabric, then a thick layer of Road Base or Crushed Concrete compacted in lifts. A top layer of #57 Crushed Stone or Driveway Gravel gives a clean surface. Crown the middle so rain runs to the edges, and give it a path out at the low end. With 0 days at 32 F or colder at the Honolulu station, the base never has to fight frost, only water.^[3]

Garden beds and borders benefit from stone and mulch together. Brown Shredded Mulch, Black Shredded Mulch and Red Mulch keep the soil cool and slow down weeds, but a hard downpour can float loose mulch away. A border of River Rock or Pea Gravel along drip lines and walkways holds its place in heavy rain. Wood Chips work well under trees and around play sets, and they break down slowly into the soil.^[3]

Patios, paths and outdoor rooms use finer material. Pavers sit best on compacted Road Base with a thin bed of Concrete Sand or Stone Dust Screenings. A garden path can use Decomposed Granite or Walkway Gravel, which pack into a surface firm enough to walk on. #89 Crushed Stone and 3/8" Crushed Stone suit the gaps between stepping stones. Mason Sand is the choice for mortar work on low garden walls.^[2]

Larger site work uses the heavy grades. #4 Crushed Stone and Railroad Ballast make a stable first layer over soft ground before a lighter base goes on top. Asphalt Millings give a long lane a dark, firm surface that binds in the sun. Fill Sand levels a low spot before a slab or a shed. The 730 feet reading at Honolulu's center point tells you nothing about your own slope, so look at where water runs on your lot before you decide on a layout.^[1]