NWDTW 2024

Temperature is a principal driver for a variety of in-stream processes including but not limited to biotic activities, chemical reactions, and changes in fluid properties. Additionally, changes in precipitation patterns, snow cover, stream shading, groundwater inputs, and air temperature are driving factors for stream temperatures. The Illinois River Basin supports a variety of uses such as wildlife habitat, power generation, and recreation. Higher in-stream temperatures can lead to harmful algal blooms and other biological and chemical extremes that can cause diminished or toxic habitat for wildlife and limit the human use of streams and rivers within the Illinois River Basin.

As part of the Next Generation Water Observing System (NGWOS) project in the Illinois River Basin paired air and water temperature probes were deployed at 34 sites in 4 major tributaries to the Illinois River and includes monitoring upstream and downstream of 3 reservoirs. This broad spatial distribution using relatively low-cost temperature probes will provide a dataset that could be used to inform numerous research questions across disciplines and agencies.

The objective of this effort is two-fold: (1) to assess the effects of different environmental factors on temperature dynamics in surface water and, (2) to quantify the effect of reservoirs on stream temperature in reaches downstream of a dam. Specifically, what are the major drivers for stream temperatures within the Illinois River Basin and how do these drivers change seasonally or geographically within the basin.