I'll provide a historical view of the fish barrier... Around 2002, during my previous tenure as lake manager, I researched the possibility of a fish barrier for Lake Carroll due to our escapement issues (not only muskie, but walleye, smallmouth bass and many other sport species). Some of you are aware of other systems that have been put in place like Kinkaid Lake and Shabbona Lake.
We were interested in placing a net in front of our spillway (in the lake), like Shabbana had. We felt that we could maintain a barrier system on our dam because we've got such a strong volunteer force to monitor and help maintain it... However, the regulations in place by the regulatory commission of IDNR-DWR make it virtually impossible to install a physical barrier. The problem is that the barrier can (potentially) clog with debris, therefore causing a backup of water, therefore changing the hydraulic pressures / residencies on the dam and possible pre-mature over-topping of the emergency spillway (NOTE: The number ONE cause of dam failures is overtopping). With these concerns / problems we started to look into electric deterrent systems. (It's basically an electric field that 'shocks' the fish and tries to deter them from coming closer to the spillway, and potentially over. It's not a physical barrier, so it won't stop them all, but could deter them from getting too close and washing over.)
At that time, the costs of the barrier were pretty high (I don't remember exacts, but I think it was in the $50,000 range just for the equipment). I would think some of this technology has come down. (I've seen some 'kits' from over-seas that we may be able to do ourselves too). There was also 'safety concerns' raised due to the electrical current and public access, running power, what operating costs would be etc.
Once the fish are over the spillway and into the basin / creek below, they become labor intensive to collect and restock into the lake. (Not impossible, as we've cleaned the spillway of game fish for years with volunteer help). Also, once they are over the spillway, we can only retrieve a percentage of those fish... There is also concern for fish migrating up the river that were not Lake Carroll fish being stocked into the lake. (this is an increasing concern due to VHS infections, parasites etc and was brought up at fish replenishment committee meetings last year by one of the members. I agree with his concerns and we should be cognizant of the risks).
Once I left about 7 years ago, I don't know what happened with the barrier / research.
After I returned last year, the fish replenishment committee and I began discussing the barrier issue again. The desire, at that time, was to determine if we can have a barrier down stream. In short, I contacted the IDNR-DWR and they said it would be 'possible' to put a barrier below the spillway, but it would need to be engineered and specific parameters would need to be adhered to (such as the top of the barrier can be no higher than the spillway basin wall). The direction this needs to go now is to determine the costs to engineer the barrier to acceptable regulations by the regulatory group (IDNR-DWR), determine if this system, once designed, would actually keep all the fish in it, what will it take to keep it cleaned out of game fish, and how do we do it (shocking boat, nets, volunteers, staff), the fish replenishment committee needs to request the project for funding by the Lake Committee, and it needs to be put into the budget process. All of which are possible. After that, it's up to the budget vote and whether or not we get support to do the work. I asked ranger375 for copies of pics / videos so the replenishment committee can use them to show people the problem / concerns for support of funding for the net or barrier. I plan to bring this up for discussion at the Lake Committee meeting on Monday night since we are discussing budgets for upcoming years. Thanks Joe