Perhaps the best known unconfined aquifer is the Ogallala. In many places this aquifer is near the surface and recharge depends on water that collects at the surface in wetlands. ... A playa lake is a naturally occurring wetland (averaging about 17 acres) formed when rain fills small depressions in the prairie. (https://texasaquaticscience.org/aquifers-springs-aquatic-science-texas/)
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