Archive | January, 2011

Dynamics of Wisconsin’s Turtle Flambeau Flowage

2010 turned out to be a pretty incredible year for water fluctuations on the Turtle Flambeau Flowage (TFF). The quantity and quality of both summer and winter recreation on this 14,000+ acre body of water in Iron County, Wisconsin is entirely dependant on the ever changing water level of this impoundment.

Water levels for the Turtle Flambeau Flowage as tracked by the Wisconsin Department of Natural ResourcesThis part of the State of Wisconsin was classified as a severe drought area from 2005-2009. The TFF depends on rain and the inflows of the Manitowish, the Turtle, and the Flambeau Rivers as well as a number of creeks in order to maintain full pool. Outflows at the Turtle Dam into the downstream Flambeau River vary from 300 cfm in the summer to 600 cfm in the winter. When output exceeds input, as was the case in 2005-2009, water levels are low and the quality of recreation on the Flowage is poor.

This past year changed everything for the TFF. Full-pool was not achieved for the game fishing Opener in early May. The water level was down three feet from full pool. Initially, it looked like 2010 would be another drought year. Then the rains came in late June, and they never stopped. By mid-July, the water level was within inches of full pool, due to frequent, heavy rains and rushing rivers pumping more water into the Flowage. Recreational potential improved dramatically.

Why does this matter? The massive size of the TFF plus the thousands of islands which dot it, are a popular fishing, camping, and vacationing destination. The Department of Natural Resources (DNR) maintains hundreds of free camping sites on the islands. The TFF is a virtual walleye factory with a rapidly growing smallmouth bass fishery. Ninety percent of the TFF shoreline is state-owned wilderness. There simply isn’t another body of water like the TFF. So there’s a lot at stake when making decisions on how to manage it.

The TFF is regarded by the DNR as being the most hazardous body of water in the state for navigation. Low water levels make that situation worse. The TFF is notorious for floating timber, thousands of stumps that sit just below the surface where they are out of sight of boaters, and rock bars or single rocks as big as a car lurking just below the surface. It takes years for boaters or fisherman to learn where the “safe lanes” for navigation are located. The learning process can be accelerated by fishing with a guide. When water levels are low, even safe boating lanes can be treacherous.

In a normal season, the water level of the TFF would decline beginning in early July by as much as four feet below full pool by mid-August. Much to everyone’s delight, this did not happen in 2010. Near full pool water levels were maintained all the way through November despite efforts to bring the water level down by increasing the discharge at the dam to as much as 1500 cfm.

The maintenance of full pool throughout the summer months is ideal (but rare) for both tourists and vacationers. The 2010 water level situation was a bonus for everyone. Even though the Flowage was constantly losing water that was being discharged at the dam, the rains continued and filled the impoundment back up. That’s how man-made impoundments are supposed to work. During the drought years, this seemed to be an impossible task.

The Flowage is normally drawn down by as much as eight feet beginning in September. The purpose of the draw down is to accommodate the melting snow and ice in the spring, which normally fills the FlowageOutflow at the Turtle Dam for the Turtle Flambeau Flowage as tracked by the Department of Natural Resources back to full pool; even though this did not happen in 2005-2009. In fall 2010, the DNR and Xcel Energy, who manage the Turtle dam cooperatively, decided to draw the TFF down by only 2.5 feet for the winter. The logic of this decision was not publicized. But those who live on and use the Flowage suspect that the drought years of 2005-2009 had taught everyone a lesson. It’s extremely difficult to fill the Flowage back to full pool in early May when the water level has been eight feet below full pool all winter. Snow and ice runoff, rain, and river inflow could not get the job done. And that hurt property owners, fisherman, boaters, and the local tourist industry in general. Property owners had no idea where to put their docks. Fisherman found their favorite fishing spots exposed. Boaters would often not even attempt to navigate water levels that were four feet lower than normal. And tourists would be absent.

The decision for the less drastic draw down was applauded by everyone. This would make it far easier to bring the water level up 2.5 feet before the early May game fishing Opener. And if there is too much water, the Turtle Dam can be opened further to adjust water levels, as long as there is no risk of flooding property below the dam.

The first real test of this new approach to managing the TFF will be the first Saturday in May 2011. That day is Opening Day for the 2011 open water game fishing season. No one knows what the snows in winter or the rains in spring will bring to the equation. But after experiencing the drought years of 2005-2009, the conclusion is that more water is better than low water. And that benefits everyone. Stay tuned. This approach is an experiment and the weather must assist in making it a successful experiment. We all know that the weather can often be a fickle partner.

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