Big Spring's water turns cloudy because of drought

VAN BUREN, Mo. -- Big Spring in the Ozark National Scenic Riverways is known for the clarity of water that flows from one of America's three largest springs, but recent visitors may have noticed something different.

Water flowing from the spring near Van Buren has taken on a cloudy, milky color for about the last week.

"The cloudy appearance of Big Spring is due to a natural geologic event in the recharge area of the spring," said Faye Walmsley, chief of interpretation and public information officer. "We don't know the exact source, but it is associated with the low flow of the spring. Due to drought conditions, Big Spring's flow is currently below average."

Underground conduits bring water to Big Spring from an area of about 426 square miles.

Recorded rainfall for some towns in the area is as much as 10 inches below normal and spring flow has been consistently dropping.

It had dropped to 344 cubic feet per second as of Thursday, more than 80 cubic feet per second below the typical average for this time, according to U.S. Geological Survey gauges.

Samples will be taken of the water, which appears to be less cloudy now than when the issue was first noticed, according to Victoria Grant, natural resources manager.

More information is needed to know for certain what has caused the change in the appearance of the water at Big Spring, or how long it will remain this way, she said.

It's possible the pressure of the flow of water helps maintain the underground structure of conduits which feed Big Spring, Grant continued.

"If there is low flow, perhaps it has caused the collapse of parts of the conduit and carried sediment through," she said.

Studies have shown the water normally carries a load of dissolved limestone equivalent to 70 tons a day, according to the ONSR.

Previous changes in flow have ranged from a low of 236 cubic feet per second in 1956 to as much as 2,000 cubic feet per second in the mid-1980s.

More information about Big Spring is available by contacting Walmsley at 573-323-4844.

Pertinent address:

Van Buren, MO