Dissolved Oxygen Monitoring

(Last Updated - 3/24/2023)

Department staff measures dissolved oxygen during annual water quality sampling in lakes across the state. Most sampling occurs in late January through February.

While staff don't sample every lake in the state, attention is focused on lakes where fisheries managers are concerned with the potential for low dissolved oxygen.

When last tested, the lakes listed below had oxygen concentrations below 2 ppm, which is a threshold that causes concern for biologists.

Winterkill is not guaranteed at those levels, but some of the lakes on this list may experience some level of winterkill.

If anglers observe large numbers of dead fish on any of these, or other lakes, they should report it to the Game and Fish Department (701-328-6349).