BETTER WATER QUALITY A RESULT OF LOW MISSISSIPPI

Water quality and navigation haven't been adversely affected by the relatively low stage of the Mississippi River in this drought year. In fact, the quality of water Cape Girardeau is taking from the river is better than usual.

The river is running clearer than normal because the absence of rain has reduced runoff, silt and turbidity, says Kevin Priester, manager of the water system. The lack of rain also has reduced pesticide runoff. "The quality of the river water is pretty good," Priester said.

Navigation between St. Louis and Cairo, Ill., has not been affected by the low water, according to Harold Bodd of METCO Barge Lines. But that could change."If it fell another 3 or 4 feet we would start getting into reduced tow sizes," he said. How much the tows would be reduced depends on the size of the boats.

METCO currently is running 30 barges southbound with its 8,000 hp boat and 25 southbound on its 6,000 hp boat.

The forecast river stage of 10.8 feet today on the Cape Girardeau gauge is far from the lowest recorded levels the Mississippi has reached.

On Dec. 20, 1988, the river dropped to 2.9 feet on the Cape Girardeau gauge. Earlier that same summer the river was so low people were walking out to Tower Rock near Wittenberg in Perry County, a landmark normally viewed from afar.

But the record for low water at Cape Girardeau belongs to Jan . 15, 1909, when the river was at only 0.6 feet on the gauge. That represents an actual channel depth from the river bed of 13.1 feet.

The Army Corps of Engineers' mission is to maintain a 9-foot navigation channel.

Priester said the river only seems low because in recent years it has been the opposite. "It's just been so high the past three or four years we've gotten used to an above-normal river stage."Last year in early November the river stage was nearer 20 feet.

If the river stage continues low as cold weather comes on, one concern could be ice jams because the river would be much more susceptible to freezing. "If we get enough chunks of ice, the current washes them together, and they can choke off our ability to bring water in," Priester said.

Cape Girardeau has two water treatment plants: the north one near Cape Rock taking in Mississippi River water and the south one on South Sprigg treating well water. The two sources of water are mixed in the distribution system. Higher water quality means less chlorine, aluminum sulfate and lime must be used to treat the water. Chlorine is a disinfectant, aluminum sulfate works as a coagulant that clarifies the water, and lime is used to adjust the pH of the water so pipes won't leach lead and copper.

Priester said the system is saving money on chemicals but spending more money pumping water at low levels.

The treatment system currently is using about 200 pounds of chlorine and about 300 pounds of both aluminum sulfate and lime per day.

He said the water may seem to taste best in the middle of the winter when the water is near freezing. "It really doesn't taste any better," he said. "But it's like drinking warm soda versus cold soda."