"CHICAGO -- Despite decades of efforts to restore and protect the Great Lakes, dozens of old power plants still are allowed to kill hundreds of millions of fish each year by sucking in massive amounts of water to cool their equipment.
Records obtained by the Chicago Tribune show that staggering numbers of fish die when pulled into the screens of water intake systems so powerful that most could fill an Olympic swimming pool in less than a minute. Billions more eggs, larvae and juvenile fish that are small enough to pass through the screens are cooked to death by intense heat and high pressure inside the coal, gas and nuclear plants.
Then the water is pumped back into Lake Michigan and the other Great Lakes up to 30 degrees hotter, encouraging the growth of oxygen-depleting algae that kill fish and foul beaches.
Known as 'once-through' cooling, the process is banned at new power plants. But for nearly four decades, federal and state environmental regulators largely have ignored the issue at old plants, even as fish populations decline sharply throughout the lakes and states spend millions of taxpayer dollars to stock the waters with game fish."