Hydro-Excavate, Hydro-Excavation, Soft dig, potholing, daylighting, vacuum boring, vacuum excavation, S.U.E., utility location, remote digging, hydro vac, frozen dig, cold weather excavation
In most cases, yard for yard comparison between a Hydro-Excavator and a bucket machine favors the bucket machine. However, the actual removing of the dirt is only a small part of the overall job. Let us look at the following job:

Acme Utility Co. has contracted you to uncover a 2' x 2' area they believe to be 6 feet underground. Backfill with clean material and restore to original condition.
Option 1: Conventional Method:

Open hole with sloped sides to allow for legal hand digging for exposure of utility.

Operation
Time
Cubic Yards
Crew
Amount
Unchain, unload & stage equipment
0.5 hr.
.
.
.
Uncover utility
3.0 hr.
13.3
4
.
Backhoe, Dump truck
.
.
.
.
Backfill (compacted)
2.0 hr.
12.1
.
.
Restoration (196 sft)
1.5 hr.
1.2
.
.
Reload Equipment
0.5 hr.
.
.
.
.
7.5 hrs.
26.6
.
 .

Option 2: Hydro-Excavation Process:

Open hole for exposure of utility. There is no need to slope because this process keeps workers on the surface, not in the excavation.

Operation
Time
Cubic Yards
Crew
Amount
Park truck, turn on vacuum & water
3 min.
.
.
.
Uncover utility
0.5 hr.
0.89
2
.
Hydro Excavator
.
.
.
.
Backfill (compacted)
25 min.
0.89
.
.
Restoration--not necessary; sod was cut & peeled back at start of excavating.
1.5 hr.
1.2
.
.
.
2.5 hrs.
3.0
.
.

These tables illustrate the time, labor and cost savings between the different methods. Also note that Crew "C" will be occupied on their site almost all day; meanwhile Crew "H" has plenty of time to mobilize to multiple sites.