The difference between a straightforward excavation in south-end Barrie and one near Kempenfelt Bay often comes down to one thing: water. The sandy soils along the waterfront can drain in hours, while the dense silty tills up toward the Georgian College area hold water for weeks. That contrast makes a single textbook permeability value useless here. In our experience, you need a in-situ permeability measurement tied directly to the strata you are dealing with. Whether it is a falling-head Lefranc test in a borehole through varved clay or a multi-stage Lugeon test in the fractured limestone of the Simcoe Group, we generate the field data that dewatering designers and foundation engineers actually need.
A single Lugeon test in fractured limestone reveals more about excavation risk than a hundred lab permeameter samples.
Process and scope
Site-specific factors
Barrie sits at roughly 250 meters above sea level on the western shore of Lake Simcoe, with more than 150,000 residents and a construction season compressed between spring thaw and early winter. The city's average annual precipitation exceeds 900 mm, and snowmelt in March and April saturates the upper two meters of soil. A permeability test run in August will give you a false sense of security if your excavation is scheduled for April. In our experience, the biggest risk lies in thin sand lenses interbedded within the Newmarket Till. These lenses are barely visible in split-spoon samples, but they can transmit water laterally from a nearby creek or stormwater pond. A properly executed field permeability test—with the water level stabilized for at least 24 hours prior—will reveal these hidden conduits before they become a problem.
Regulatory framework
ASTM D6391-11: Standard Test Method for Field Measurement of Hydraulic Conductivity Using Borehole Infiltration, NBCC 2020: Division B, Part 4 – Structural Design, Section 4.2.4 – Groundwater and Hydrostatic Pressure, USBR 7310-89: Procedure for Performing Lugeon Tests in Rock Boreholes, ISO 22282-2:2012: Geotechnical Investigation and Testing – Geohydraulic Testing – Part 2: Water Permeability Tests in a Borehole
Related services
Lefranc Falling-Head Test in Soil
A screened section is isolated below the water table in a cased borehole. We induce a sudden head drop and log recovery over time. This method works well in the silty tills and varved clays found throughout Barrie's older neighborhoods.
Lugeon Packer Test in Bedrock
We use a double packer assembly to isolate a specific fracture zone in the Simcoe Group limestone. Water is injected at five increasing pressure steps, held, then stepped down. The Lugeon value defines rock mass permeability and identifies hydraulic fracturing potential.
Constant-Head Test in High-Conductivity Soils
For the clean sands near the Barrie waterfront or along the Highway 400 corridor, a falling-head test drains too fast. We maintain a constant water level while measuring the inflow rate, yielding a stable conductivity value for dewatering system design.
Multi-Level Piezometer Installation
After permeability testing, we often install nested vibrating-wire piezometers in the same borehole. This provides long-term pore pressure data at multiple depths, directly correlated to the permeability profile. Essential for phased excavation projects near Lake Simcoe.
Typical parameters
Frequently asked questions
How much does a Lefranc or Lugeon test cost in Barrie?
A single Lefranc test in a soil borehole typically runs between CA$950 and CA$1,240, inclusive of mobilization within the Barrie area, packer setup, data acquisition, and a signed report. A multi-stage Lugeon test in rock falls at the upper end of that range or slightly higher if a double packer is required. The final cost depends on the number of test intervals, depth, and access conditions.
How long does a field permeability test take on site?
Plan on half a day per borehole. The actual injection or falling-head phase may last only 20 to 40 minutes, but we need time for water level stabilization before the test and for packer inflation checks. If we are testing multiple zones in one deep borehole—common in the fractured limestone north of Barrie—the entire sequence can extend to a full day.
When is a Lugeon test required instead of a Lefranc test?
A Lugeon test is the correct choice when you are advancing into bedrock, particularly the fractured limestone and dolostone of the Simcoe Group that underlies much of Barrie. The packer system allows you to isolate a specific fracture or joint set under pressure, which a simple Lefranc screen in an open borehole cannot do. If your project involves rock sockets for caissons or a deep sewer tunnel, the geotechnical report will almost certainly specify Lugeon testing.