Dissolved solids can negatively impact livestock drinking water. To characterize dissolved solid concentrations in the northern Great Plains, we studied 45 water sources over 11 yr. Ca, F, Mg, Na, and total solids sometimes exceeded recommended levels but rarely reached levels empirically shown to negatively impact livestock. Fe often attained concentrations that reduce water consumption, which can reduce feed intake and weight gain. Excessive Fe was likeliest in creeks and reservoirs. SO₄ sometimes reached concentrations that reduce weight gain but rarely reached concentrations causing health problems. Excessive SO₄ was least likely in reservoirs. A safeguard against water quality problems is ensuring livestock can access multiple water source types (e.g., wells and reservoirs) so that they can use taste and smell to choose acceptable water. Where this is impossible, water quality monitoring is of greater importance. Inexpensive electrical conductivity meters roughly estimate water quality and can identify watering locations requiring more detailed monitoring.