Lake Abert's Suppressed Rebound: Evidence for Loss of Groundwater Buffering

Lake Abert is a small, shallow, endorheic lake with a simple and traceable surface‑inflow structure. Historically, its elevation tracked cumulative flow closely, with several periods (1930s, 1950s, 1970s) showing inversions where lake level rose despite low inflow—a signature consistent with groundwater buffering. After ~2000, this relationship breaks down: lake elevation no longer responds to wet years, indicating an additional hydrologic mechanism. Because the basin lacks groundwater and diversion data, the mechanism cannot be assigned with certainty, but the lake’s behavior is consistent with loss of groundwater buffering due to increased pumping or interception of subsurface flow. Abert’s simplicity makes it an ideal diagnostic system for identifying mechanisms that may be harder to detect in larger basins.