Jersey City grew fast on filled tidelands and basalt ridges. That history created a patchwork of subsurface conditions where water moves unpredictably. A field permeability test (Lefranc/Lugeon) gives the direct hydraulic conductivity value for design, not an indirect lab estimate. We run these tests across Downtown, Journal Square, and the West Side to support dewatering plans, cut-and-cover excavation design, and permanent drainage strategies. The data feeds directly into groundwater control specifications required by IBC and local building departments. For deep basements near the Palisades, combining the Lugeon test with seismic refraction helps map how water flows through fractured basalt before any shoring goes in.
A single Lugeon test in fractured basalt tells you more about real water inflow than a dozen lab perm tests on intact core.
Service characteristics in Jersey City
Critical ground factors in Jersey City
The most common mistake in Jersey City is running a single falling-head test in a shallow borehole and using that one number for the whole excavation design. The fill varies—old bulkhead lines, buried timber, uncompacted sand—so permeability can change two orders of magnitude in 30 feet. We have pulled Lugeon data from rock sockets where water take jumped from 2 L/min to 45 L/min across a single fracture zone. If the dewatering contractor doesn’t get that profile, the pumps are undersized. The basement floods during a nor’easter, and the general contractor owns the delay. For deep urban excavations in constrained sites, we often recommend real-time monitoring alongside the permeability program.
Our services
We deliver permeability testing as a standalone scope or integrated into a broader geotechnical investigation. Every project includes a signed field log and a stamped engineering report.
Lugeon Packer Test
In-situ rock mass permeability using single or double packer. 5-step constant-head injection per USBR procedure. Directly measures Lugeon units and equivalent k.
Lefranc Test
Variable or constant head test in granular soil. Slotted wellpoint installation by driving or rotary wash boring. Measures hydraulic conductivity for dewatering design.
Combined Permeability Profile
Sequential Lefranc and Lugeon tests in the same borehole, from overburden into bedrock. One log, one rig mobilization, complete vertical permeability profile.
Common questions
What is the difference between a Lefranc test and a Lugeon test?
Lefranc is for soils; Lugeon is for rock. Lefranc measures hydraulic conductivity by adding or removing water from a slotted wellpoint and tracking head change. Lugeon uses a packer to isolate a section of borehole in bedrock and injects water at constant pressure steps. We apply the method that matches the formation.
How deep can you test in Jersey City?
We routinely test to 80 feet in soil with Lefranc and up to 120 feet in rock with Lugeon. Depth depends on the rig access and the borehole diameter. In tight Jersey City lots, we use compact track-mounted rigs that can reach those targets.
What does a field permeability test cost?
A single test typically runs between US$560 and US$1,060, depending on depth, packer configuration, and number of pressure steps. A combined Lefranc-Lugeon profile in one borehole is priced by the total test intervals.
How long does it take to get results?
You get a verbal summary with raw data the same day. The final signed report with interpreted k values and Lugeon units is delivered within 48 hours. We can push faster for active dewatering tenders.
Do I need a Lugeon test if I already have core samples?
Yes. Lab permeability on intact core misses fractures, joints, and bedding planes where most water flows. Lugeon tests the rock mass at scale. In fractured Watchung Basalt, lab values routinely underestimate field permeability by 10 to 100 times.