sentences:  The springs are fed by water from the Edwards Aquifer; this water reaches the surface through faults along the Balcones Escarpment.There are 13 primary springs, but they seldom flow due to pumping demands on the Edwards Aquifer.In addition to the association of groundwater availability with this locale along the Balcones Fault, the area is also considered an ecological dividing line for occurrence of some species; for example, the California Fan Palm, "Washingtonia filifera" occurs only at or west of San Pedro Springs, i.e.