(New throughout, adds flood risk to Kansas City suburb of Parkville; no threat to downtown Kansas City airport; disaster declaration for Iowa; Fort Leavenworth little affected)
By Karen Dillon
KANSAS CITY, Mo., March 23 (Reuters) - Record flooding along the Missouri River has impaired treatment of drinking supplies in Kansas City, raising health risks for infants, the elderly and others with compromised immune systems, the municipal water service warned on Saturday.
The public health advisory came as utility crews struggled to replace broken pumps at a wastewater treatment plant submerged by floodwater about 30 miles upstream in Leavenworth, Kansas, an historic town of 35,000 on the river's west bank.
The crest of the flood-swollen Missouri, America's longest river, rolled through Leavenworth on Saturday. Miles of farmland and wooded areas along both banks were inundated in murky brown water. It was expected to reach Kansas City, Missouri, the state's largest municipality, early on Sunday.
By Saturday, high water was creeping to the edge of the scenic commercial district in Parkville, Missouri, a riverfront suburb of 6,700 residents just upstream from Kansas City known for its antique shops, art galleries and restaurants.
Nevertheless, flooding in the immediate days ahead was not expected to reach the catastrophic scale seen in Nebraska and Iowa to the north, as excess flow continued to dissipate along the length of the river.
Charles B. Wheeler Downtown Airport, situated on a river bend behind a tall levee in the heart of Kansas City, Missouri, expected no flood-related disruptions, an airport official said.
Drinking water in the city became an issue even before the flood crest arrived. The KC Water utility, which serves 170,000 mostly residential customers with water drawn from the river, said it had failed to meet "enhanced treatment technique standards."
TAINTED DRINKING WATER?
Testing showed excessive levels of turbidity, fine particles in the water that can carry bacteria, viruses and parasites including Cryptosporidium, which can cause diarrhea.
KC Water spokeswoman Brooke Givens said Cryptosporidium itself has not been detected, but "the state requires us to notify customers" whenever testing shows the treatment system's filters are failing to control turbidity.
The high volume of rain and snow melt runoff flowing through the Missouri has carried excessive silt and other material, changing the taste of the water in recent weeks, Givens said.
"With all that runoff, we're seeing river conditions like we haven't seen in more than a decade," she told Reuters.
KC Water said the diminished water quality was not considered an emergency but advised customers with compromised immune systems, the elderly and those with infants to seek medical advice before drinking tap water.
Floods were unleashed when last week's "bomb cyclone" storm dumped torrential rains atop hundreds of square miles of the snow-covered Plains.
Record flows cascaded into the Missouri River watershed, and flooding killed at least four people, drowned livestock and closed dozens of roads across a wide swath of Nebraska and Iowa. Property losses were estimated at more than $3 billion in those two states.
U.S. President Donald Trump declared a major disaster on Saturday for 56 Iowa counties, making federal recovery assistance immediately available. He issued a similar declaration on Thursday for Nebraska.
The engorged river crested higher at a record level of over 32 feet (9.75 meters) on Friday at the waterfront city of St. Joseph, Missouri, forcing some 7,500 people to flee from low-lying areas.
Evacuation orders were lifted as floodwater receded on Saturday. But the river in Leavenworth on the Kansas side just downstream crested at 31.4 feet, the second-highest on record there after a 1993 flood in which the river topped 35 feet.
Leavenworth Police Chief Patrick Kitchens said workers and volunteers were sandbagging a riverfront community center converted from a 19th-century rail station to protect the building from floodwater.
A bigger concern, he said, was the town's flooded wastewater treatment plant.
Fort Leavenworth, a U.S. Army garrison in town that ranks as the oldest permanent settlement in Kansas and houses a military prison complex, escaped serious damage, though its air field was under water, base spokesman George Marc said.
He said the garrison has no regular flight operations and had already towed the few private planes kept on base to higher ground. (Reporting by Karen Dillon in Kansas City; Additional reporting and writing by Maria Caspani in New York and Steve Gorman in Los Angeles; Editing by Chizu Nomiyama and David Gregorio)
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