A small subdivision is a lot of earthwork packed into one set of plans. Mass grading, lot pads, utility trenches, stormwater ponds and erosion control all have to line up with the engineer's design and the city's inspections. We take on that work for small developments and multi-lot projects, and we're happy to look at your plans and talk about scope.
Subdivision Earthworks in Boise and the Treasure Valley
New lots keep going in across the valley. Infill splits in Boise, a dozen lots on the edge of Meridian, a few acres of former pasture in Kuna, Star or Middleton. Every one of them starts with the same thing: the ground has to be graded, drained and stubbed for utilities before a single house can go up.
We're a small, Caldwell-based contractor, and smaller subdivisions and multi-lot projects are the kind of development work that fits us. If you're a developer or builder with a project on the table, send the plans and we'll talk through what part of the scope makes sense for us.
Mass Grading to the Civil Plans
The engineer's grading plan sets the finished elevation of every lot, street and pond. Our job is to get the dirt there. That starts with stripping topsoil and stockpiling it for later, then cutting and filling to the grades on the plan, working from the surveyor's stakes.
Fill under streets and pads goes in compacted lifts, and on most subdivisions a testing firm checks density as it goes. The geotechnical report matters here. Caliche, clay and high groundwater all change how the site gets graded. See compaction.
Lot Pads Ready for the Builder
A builder wants to show up and dig a foundation, not fix a pad. Each lot gets brought to its pad elevation, compacted, and graded so it drains the way the plan shows, usually to the street or to a swale along the back lot line. Clean, accurate pads make the site cut on each house go faster. Before builders take over, it helps to walk the lots with the developer and check pad heights against the plan. Catching a pad that's a little high now costs far less than finding it when the first foundation goes in.
Utility Trenching for Multi-Lot Projects
Sewer and water mains, service stubs to each lot, storm lines, and joint trenches for Idaho Power, Intermountain Gas and communications. We dig and backfill to the specs of the city and each utility, and coordinate with the crews setting pipe and conduit. Trenches 5 feet or deeper are sloped, benched or shored under OSHA rules, and sewer mains often run that deep. See underground utilities.
On a multi-lot project, the order of the trenches matters. Deep sewer usually goes in first, then water and storm, then the shallower power, gas and communications lines. Trench backfill under future streets gets compacted in lifts and tested by the testing firm before paving. We work out that sequence with the developer and the pipe crews so one trench doesn't undercut another.
Stormwater Ponds, Swales and Erosion Control
Many valley subdivisions handle storm runoff on site with retention ponds, swales and other features the engineer designs. Those have to be dug to the right depth and side slope, and the bottoms often shouldn't be compacted, since the water needs to soak in. See drainage excavation.
Projects that disturb an acre or more generally need construction stormwater permit coverage. That means erosion controls go in before the dirt starts moving, like silt fence, inlet protection and a gravel construction entrance, and they get kept up until the site is stabilized.
Working With the Developer, Engineer and City
Subdivision earthwork has a lot of people involved. The developer sets the schedule and budget. The engineer owns the design. The city, and often a highway district, inspects the streets and utilities. An irrigation district may own a ditch that has to be piped or relocated, and pressurized irrigation lines often go in alongside the other utilities.
When the plans don't match what's in the ground, we raise it with the engineer early instead of guessing. Our reviews say we "value communication and arrive on time," and on a multi-party job that's most of the work.
Phasing and Weather
Many smaller developments get built in phases, and the earthwork follows that plan. Grading one phase while the next sits idle means keeping erosion controls up on both, and stockpiled topsoil may sit for a while before it goes back. Wet spring weather and frozen ground in winter both limit when clay and fill can be compacted, so grading often leans on the drier months. We'll talk through realistic timing with you before anyone commits to dates.
Send Us Your Plans
The fastest way to find out if we're a fit is to send what you have. Even a partial set helps us give you a straight answer on scope and timing. The most useful pieces are:
- Civil set and grading plan
- Geotechnical report
- Phasing and schedule
- Any scope you've already split out to other contractors
We'll look it over and tell you plainly what we can take on, whether that's the whole earthwork package or a piece of it like lot pads or erosion control. For commercial pads and parking areas, see commercial excavation.
Why Hire Ultimate Excavation LLC
We're a registered Idaho contractor (RCE-65836) with a 5.0 rating on Google, and Tanner is the person you'll talk to from the plan review on. If part of the scope is more than a contractor our size should take on, we'll say so up front and talk about the pieces that do fit. Call (208) 697-2429 or request a free estimate.
