Illinois EPA says it’s in contact with the city of La Salle about discolored water

The Illinois EPA is in contact with the city of La Salle as it upgrades its filters at the Water Treatment Plant, Illinois EPA Public Information Officer Kim Biggs said.

Last week the city released a statement saying some discoloration in water may be present in some neighborhoods over the next few weeks as the city continues maintenance of its water treatment plant.

A filter at the plant is under maintenance, which has led to a higher amount of water going through the plant’s other filter, which results in the discoloration from an increase in iron and manganese, the city said.

Briggs said the maximum contaminant level, which is the highest level a contaminant may be following applicable state regulations, for manganese is 0.15 micrograms per liter and 1.0 mg/l for iron.

Monthly operating reports for finished drinking water in La Salle indicate 0.05 mg/l for manganese and 0.02 mg/l average for iron, each of which is below the MCL, according to the EPA.

There were three days with finished water over 0.1, but within the MCL, Briggs said.

“The city is also collecting daily manganese samples from the distribution system,” she said. “With levels intermittently reaching 0.1 mg/l, it may cause some discoloration.”

Briggs said chlorine concentration tests are being performed at three sites daily to ensure compliance.

“The residual free chlorine must be over 0.5 mg/l for the protection of public health,” she said. “And is effective in the control of bacteria in the distribution system.”

The work at the water treatment plant is expected to last an additional four to five weeks. In the meantime, the city said it has taken measures, including backwashing more frequently, which is a method of preventative maintenance. Officials also are flushing hydrants more often to assist with the discoloration.

“Illinois EPA has not received any citizen complaints on the issue,” Briggs said. “But, we will continue to monitor the situation.”

The water was questioned by a couple residents during the City Council meeting on Monday.

For more information, call Superintendent of Water Treatment Brad Reese at 815-223-0068.

What do health departments say about manganese/iron in water?

At concentrations greater than 0.05 mg/L, manganese may cause a noticeable color, odor, or taste in water, according to the Connecticut Department of Public Health. However, potential health effects from manganese are not a concern until concentrations are about six times higher, the agency said.

One group that should take notice of manganese levels are pregnant women and mothers of infants. Infant formulas contain manganese, and if prepared with water that also contains manganese, the infant may get a higher amount than the rest of the family. In addition, infants appear to absorb more manganese than older people but excrete less. This adds up to a greater potential for exposure in the young. Since manganese’s effects on the developing nervous system have not been adequately studied, it is especially important for pregnant women and young children to have drinking water that is below the manganese level of 0.3 mg/L.

As for iron, when exposed to air in the pressure tank or atmosphere, the water turns cloudy and a reddish brown substance begins to form, according to the Illinois Department of Public Health. Sediment is the oxidized or ferric form of iron that will not dissolve in water. Dissolved ferrous iron gives water a disagreeable metallic taste. When the iron combines with tea, coffee and other beverages, it produces an inky, black appearance and a harsh, unacceptable taste. Vegetables cooked in water containing excessive iron turn dark and look unappealing. Concentrations of iron as low as 0.3 mg/L will leave reddish brown stains on fixtures, tableware and laundry that are very hard to remove. When these deposits break loose from water piping, rusty water will flow through the faucet.