Site preparation cost

STA 0+120What "site preparation" covers

Site preparation is the set of operations that happen before the main earthworks, foundation or paving package starts, and after it finishes:

• Topsoil and subsoil stripping. Removing the organic surface layer so it is not buried under fill or a road structure, and stockpiling it for reuse.
• Subgrade preparation. Shaping, compacting and proof-rolling the surface a granular base or foundation will sit on, so it is firm and to grade.
• Erosion and sediment control. Silt fence, check dams and soil coverings that go in before the ground is disturbed, not after the first rain.
• Topsoil placement and seeding. Putting stripped topsoil back on slopes, ditches and boulevards once the main work is done, and seeding it to stop erosion.

The full sequence and how it connects to bulk cut-and-fill is covered in the earthworks and excavation discipline page.

STA 0+2402026 prices

Alberta's 2026 provincial averages, across contracts tendered May 1, 2025 to June 24, 2026:

Stripping and placing topsoil price out close to each other, $8.74 per m³¹ and $8.85 per m³¹ per cubic metre, since both are essentially the same handling operation in opposite order. Subgrade preparation is priced per square metre rather than volume: the first layer averaged $2.03 per m²¹, with a second-layer pass, where specified, at a lower $0.80 per m²¹. Regionally, topsoil placement price varies more than most items on this list, since it depends heavily on how far stockpiled topsoil has to be hauled back to where it is spread:

STA 0+360Erosion control and seeding

Erosion and sediment control (ESC) measures and the seeding that follows are priced as their own items:

Erosion control blanket ($3.98 per m²¹) stabilizes a slope until seed establishes; the three soil-covering types (A, B and C) price different levels of erosion protection for different slope and rainfall conditions. Broadcast seeding is the lower-cost option per hectare against hydro-seeding, which applies seed, mulch and tackifier together as a slurry and is generally used on steeper or more erosion-prone slopes. ESC has to be installed before the ground is opened, not after, to actually do its job — the erosion and sediment control guide covers the sequencing and the regulatory reasons why.

STA 0+480Geotextiles and geogrid: stabilizing weak ground

Where the subgrade itself is soft, wet or otherwise unsuitable to build straight on, a geotextile fabric or geogrid is placed before the granular base rather than over-excavating and replacing all the weak material. Alberta prices four grades separately by function:

Non-woven geotextile is the lowest-cost of the four and is mainly used for drainage and filtration rather than load support. Geogrid, a stiffer grid structure rather than a woven fabric, costs more per square metre and is specified where the subgrade needs actual reinforcement to carry traffic or fill without rutting. Geotextile for materials separation keeps a granular base from mixing into a soft subgrade below it over time, and geotextile for stabilization is specified where the subgrade needs help bearing load during construction. Which one a project needs is a geotechnical engineering decision, not a cost decision — using the wrong grade to save money on the unit price is a common way a subgrade fails prematurely.

STA 0+600Compaction testing: what nobody publishes a price for

Compaction testing — a geotechnical lab or field technician confirming that subgrade or fill has been compacted to a specified density, usually against a Proctor test — is a routine cost on almost any serious earthworks or site-prep job, and no government body publishes a price for it. Geotechnical testing is billed by private labs on a per-test or day-rate basis that is not part of any public tender average in this dataset. If compaction testing is required by your municipality or engineer, get a quote directly from a geotechnical firm; budget for it as a separate line item rather than assuming it is bundled into an earthworks unit price.

STA 0+720What changes the number on a small job

Alberta's averages are highway-scale. A house lot or small commercial pad prices differently:

• Mobilization and minimums. The same equipment and crew cost close to the same to bring to a small lot as a much larger one, so the cost concentrates on less area.
• Topsoil disposal or import. A highway job usually balances its own topsoil on site; a small urban lot may have nowhere to stockpile it and has to haul it off site, or may need to import topsoil if the existing material is unsuitable.
• Season. Wet or frozen ground slows stripping and compaction and can require it to be re-sequenced around weather rather than run straight through.
• Access. A site prep contractor working through a gate or around existing structures works more slowly than one on an open right-of-way.
• Ground conditions found once work starts. A geotechnical report reduces the risk, but it is still a sample of the site, not a complete map of it; unsuitable material found under the topsoil after stripping starts is one of the most common reasons a site-prep budget grows mid-job.

None of this means a small job is being overcharged at several times the highway per-unit rate — it means the cost structure of mobilization, disposal and testing does not scale down the way a highway contract's does.

STA 0+840What to send for a price

For a comparable site preparation quote: the area involved, existing topsoil depth if known, the finished subgrade elevation or design levels, whether erosion control is required by a permit or engineer, and where stripped topsoil should end up (stockpiled on site, hauled off, or reused for final grading). The cut and fill calculator and excavation volume calculator turn an area and depth into the volumes these prices apply to.