What factors besides increased rainfall can cause a playa lake to expand?

Beyond increased rainfall, a playa lake can expand due to several other environmental and hydrological factors. Specifically, expansion may be driven by increased groundwater inflow or a decrease in the rates of evaporation and transpiration.1

These factors are critical to the geomorphic evolution of playas, which are highly sensitive to changes in their hydrologic regimen. While many historical expansions of these lakes are attributed to pluvial periods—times characterized by higher precipitation—the interplay between groundwater supply and atmospheric water loss remains a primary mechanism for changes in lake levels.12