Insights · 2026-03-15
Groundwater modeling and admissibility: documentation that holds up
What courts and tribunals scrutinize in numerical models—and how transparent calibration and sensitivity analysis support reliability arguments.
Numerical groundwater models are not magical predictors—they are structured arguments encoded in grids, parameters, and boundary conditions. When models enter litigation, decision-makers ask whether those choices are documented, tested against independent data, and consistent with the conceptual site model.
Calibration is not a single number—it is a process. Defensible work shows which observations mattered, what was weighted, and what could not be matched without breaking plausibility. Sensitivity analysis then clarifies which assumptions actually move the outcome, which is essential when opposing experts argue that a model is arbitrary.
For counsel, the practical takeaway is simple: invest early in transparency. A model that is easy to audit is easier to defend—and easier to explain without losing the room.