What is in that water that you just drank? Is it just hydrogen and oxygen atoms? Is it safe for drinking? All water is of a certain "quality" (and you can't tell by just looking), but what does "water quality" really mean? Water full of dirt and grime might work fine for a tomato plant but would you want to drink it? Water quality can be thought of as a measure of the suita
All Water Quality Science Topics
View a list of all of our science topics about water quality.
Water Quality Data for the Nation
The USGS National Water Information System (NWIS) contains extensive water-quality data, both real-time and historical, for the nation.