Thursday, January 10, 1991

Pumping Stations Fulfill Role in Surging River Rise

Commercial Appeal
By Tom Charlier

The swollen Mississippi River, now carrying almost a trillion gallons of water a day past Memphis, has reached its crest after an ominous rise that forced city officials to crank up an aging pumping system to keep neighborhoods dry.

Still 2 feet above flood stage, the Mississippi fell about an inch and a quarter to a reading of 36 feet at the Memphis gauge Wednesday. The river is expected to hold at around that level until Monday, when it begins a gradual decline to as low as 24 feet by the end of the month. The crest had been expected today.

"We're looking at a very slow fall for at least two weeks," said National Weather Service meteorologist Jack Jackson, who adds that "you're going to look at water between here and the levee at West Memphis for a long time."

Even after it reaches the flood stage of 34 feet, which means the Mississippi has risen to "bank-full," or its normal carrying capacity, the river usually does not cause any damaging flooding at Memphis. But the high stages have aggravated flooding problems elsewhere in the Mid-South, where tributaries have spilled back into homes and businesses.

In Memphis, three main pumping stations, the earliest of which was completed in 1915, were forced into their heaviest duty since 1984 over the weekend. They performed without any major problems, preventing flooding along local creeks and storm sewers, city officials said.

"We always expect them to perform, but we're still a little nervous," said public works director Benny Lendermon.

Integral parts of the local flood-control network, the pumping stations provide an outlet to the Mississippi for rain-swollen creeks and storm sewers. The stations are idle most of the time, but when the Mississippi gets too high they are needed to lift millions of gallons of water over levees so creeks and sewers don't back up.

The heaviest pumping began Friday, as the river rose to a half-foot above flood stage, and lasted until early Monday, said Paul Chrestman, the city's manager of flood control.

The Cypress Creek and Nonconnah stations, built during the early 1940s, each pumped 1,000 cubic feet (almost 7,500 gallons) of water per second through the weekend.

The Cypress station, at 1522 N. Bellevue, lifted water about 20 vertical feet from a reservoir on the creek into the swollen Wolf River. The Nonconnah facility, on U.S. 61 South, pumped water from storm sewers serving South Memphis into Nonconnah Creek.

The 76-year-old Bayou Gayoso Pumping Station at 35 W. Saffarans began operation on Dec. 27, and has been pumping an average of more than 2,200 gallons per second since then. The water is lifted from sewers serving parts of downtown and Midtown into the Memphis Harbor.

Without the stations, "we'd be deep in water," Chrestman said. He added that large residential and commercial areas along Cypress Creek would be vulnerable without the station there.

The Corps of Engineers, builders of the Cypress and Nonconnah stations, has given the city many awards for maintenance of facilities and is due to present another in the coming weeks.

Additionally, the city for the first time has turned on a $2 million pumping system adjacent to the T. E. Maxson South (Wastewater) Treatment Plant in southwest Memphis.

Completed in 1985, the system pumps treated effluent from the plant into the Mississippi, supplanting the gravity-flow system that can't operate when the river hits flood stage. During previous periods of high water, the city had to dump untreated sewage into nearby drainage canals flowing into Horn Lake Creek and the Mississippi.

"In the past it really didn't create an environmental problem because it was of short-term duration, but if the (Frank C. Pidgeon) industrial park were ever developed, it would have been an unacceptable alternative," Lendermon said.

Caption:
By Lisa Waddell

On the Arkansas side of the overflowing Mississippi River, a determined man makes his way Wednesday from the Dacus Lake Boat Dock office to a nearby trailer. The river reached its crest and then fell about 1 1/4 inches Wednesday. It is expected to hold at that level until Monday, when a gradual fall will begin. Engineer Lyn Waldon and his crew at the Cypress Creek pumping station at 1522 N. Bellevue pumped almost 7,500 gallons of water per second this weekend to help prevent flooding.
photo (2)

Copyright 1991, 1994 The Commercial Appeal, Memphis, TN

Labels:

[Read the complete article...]