Stump It Out

Driveway contractors build the surface between the road and the house, from a gravel farm lane to a poured concrete approach, and the base under the surface decides how long any of them last. A typical driveway is excavated to remove topsoil, graded with a crown or cross slope so water runs off, and built up with four to eight inches of compacted crushed stone before the top layer goes on. Where the driveway crosses a roadside ditch it needs a culvert sized by the county, and the connection to a public road is regulated by the road authority. Gravel is the least expensive and needs regrading every year or two; asphalt costs more and needs sealing; concrete costs the most up front and lasts longest if the base and joints are done right.

Excavation contractors dig and move earth for foundations, basements, utilities, pools and site cuts. Most residential jobs run on a mini or mid-size excavator paired with a skid steer and a dump truck; larger cuts bring in a dozer or scraper. The price depends less on the size of the hole than on what is in the ground: clay, ledge rock, high groundwater and buried utilities all slow the machine down and change the hauling math. Before the bucket touches dirt the site needs an 811 utility locate, and any trench deeper than five feet needs a protective system under OSHA rules.

Foundation contractors build the part of the structure that carries everything above it into the ground: spread footings below frost depth, stem walls or basement walls, monolithic and slab-on-grade foundations, and pier or grade beam systems where soils are poor. The work follows the stamped plans and the geotechnical report, and it is inspected at fixed points, usually the open footing trench with rebar in place before the pour, then again before the slab and before backfill. Frost depth sets the footing bottom, from about twelve inches in the Gulf states to four feet or more across the northern tier. Waterproofing or dampproofing, a footing drain and free-draining backfill are what keep a basement dry, and they are cheapest to do right while the wall is still exposed.

Pond and water management contractors excavate and shape ponds, build or repair the embankment dams that hold them, and cut the ditches, swales and channels that move water across a property. A pond that holds water starts with the soil: it needs a clay core or a compacted clay liner, or a synthetic liner where the ground is sandy or rocky, and the dam is built in compacted lifts with a keyway cut into the original ground. Every pond also needs a way to pass the big storm, usually a principal spillway pipe plus an emergency spillway cut in natural ground, sized for the watershed above it. USDA NRCS publishes free design standards for farm ponds that most contractors follow. Cleanouts, which remove years of silt and reshape banks, are common on older ponds and are priced by the cubic yard removed and where that muck can be spread.

Trenching and underground utility contractors open the ground for pipe and conduit, bed and backfill it, and put the surface back. What looks like a straight line on a plan is governed by a few hard numbers: 811 locates before any digging, a minimum cover depth that varies by utility (commonly 18 to 24 inches for electric and gas service, and below the frost line for water), and OSHA's requirement that any trench five feet or deeper have a protective system such as a trench box, shoring or a sloped wall, with a competent person on site. Bedding material under the pipe, compaction of the backfill in lifts and tracer wire on non-metallic pipe are the details that separate a line that lasts fifty years from one that settles and cracks the driveway above it.