Waukesha’s return flow will help improve the fishery and support fish stocking programs in the Great Lakes Basin.
The base flow of the Root River has been reported since 1966 to be too low to support water quality, recreation, and fisheries goals in the watershed. The Department of Natural Resources and the Southeastern Wisconsin Regional Planning Commission have explored adding to the volume of water in the river for decades, but have been unable to augment the river’s flow because the costs were too high.
During the summer and fall, some sections of the river have very low flow, adversely affecting the fish migration from Lake Michigan. Increased flows would improve river habitat and aid the fishery, particularly during fall spawning runs of salmon and trout. At the Root River Steelhead Facility, for instance, the clean water of Waukesha’s return flow will increase river levels by 6.6 inches during low flow periods, improving fish passage.
According to the data, increasing the stream flow will be beneficial to our fisheries program goals or the Root River and Lake Michigan. Not only would increased flows have a positive impact on the number of fish entering the river and to our facility, it is also likely that the angling experiences would be expanded because, with more water, there could be more places to fish below the Horlick Dam. Then, with higher flows, fish may enter the river earlier and stay in the river for longer periods, thereby extending the angling season for these anadromous fish.
Waukesha will borrow (and return) up to 8.2 million gallons a day from Lake Michigan. This may seem like a large amount, but during high-flow events, the return flow is inconsequential compared to the total volume of water in the river. For example, during the June 2008 storm, the Root River flow measured a little over 5.2 billion gallons. Waukesha’s added outflow would have meant an increase of just 0.15%.