In Grant and Hot Spring Counties the Ouachita, Saline, and Caddo Rivers yield large quantities of soft, good-quality water. Small streams in southeastern Hot Spring County and some of the small streams in the Ouachita
Mountains have relatively high base flow; in Grant County small streams yield little water during dry periods. At times, sewage and mine drainage pollute the Ouachiba River from the Garland County line to a point a few miles below Lake Catherine. At low flow, Hurricane Creek water is unfit for most uses. The Sparta Sand, the principal aquifer, yields as much as 8.50 gpm of soft water in Grant County. The Carrizo Sand and Cane River Formation are potentially important aquifers in Grant County and southeastern Hot Spring County. The Wilcox Group yields as much as 300 gpm of fresh water in southeastern Hot Spring County and southwestern Grant County; in the rest of
Grant County its water is brackish. The alluvium along .the principal streams and ,the consolidated rocks of the Ouachita Mountains yield small quantities of water that vary in quality from place to place. Some of .the water from the alluvium has high nitrate content and may be a hazard to health.