Water Quality

Water Quality Monitoring

When you see a picture of the earth, one of the first things you’ll notice is all the water! Approximately 70% of the surface of the earth is covered by water.

Every living thing on earth needs water to survive. As humans, we require fresh water, and for many of us that water comes from rivers and lakes. It may surprise you that although 70% of the earth’s surface is water, 97% of that water is salt water, and the majority of the fresh water is either frozen or deep underground! In total, less than 1/100th of 1% of the water on earth is fresh water that is readily available for our use. This water may be underground in shallow aquifers or on the surface as lakes, streams, and reservoirs. Because water is such a precious resource, it is important that we keep it clean. We can do this by monitoring our water, and measuring many different physical, biological and chemical characteristics. 

The Tennessee Aquarium monitors the health of the Tennessee River with the help of a sonde – a device that records characteristics of the water at regular intervals. The sonde is installed on the Aquarium’s tour boat (the River Gorge Explorer), and measures the Temperature, pH, Nitrate concentration and Dissolved Oxygen content of the river once every 6 hours. This measurement normally occurs in Chattanooga, Tennessee at River Mile 464. The River Gorge Explorer operates on Nickajack Reservoir of the Tennessee River, and readings may be recorded as far downstream as River Mile 451 during a cruise. The sonde is installed inside an engine room, and samples river water as it is pumped through a chamber called a Flow Cell. This protects the monitoring equipment while providing a constant supply of fresh river water. 

More: Why measure Temperature / pH / Oxygen / Nitrates? / Additional notes


River Gorge Explorer Water Quality Results: