Salt Creek flow review not best news, not worst news. Waste water treatment plant to modify operations       

[DEC. 27, 2006]  LINCOLN -- Lincoln officials have been looking into a problem at the city wastewater treatment plant. When the plant's $10 million dollar upgrade was completed according to Illinois Environmental Protection Agency specifications a few years ago it was believed that there would be few changes needed for some years.

However, what couldn’t be anticipated was a change in the creek. According to new flow rate information compiled by the Illinois State Water Survey the creek rate had diminished and could no longer support the amount of clarified water (effluent) the Lincoln plant discharges.

The IEPA could not renew the city’s first five-year wastewater treatment plant permit.

At the recommendation of the wastewater treatment plant manager, Dave Kitzmiller from EMC, city aldermen agreed to hire a consultant to evaluate the Salt Creek flow rate figures.

Josiah Cox from Trumpet Land Services, St. Louis, MO worked with ISWS to update the figures. “Recent data more accurately reflect current condition in the Salt Creek stream systems,” the report reads.

Changes cited from the report that affected the flow rate:

• Clinton Lake was finished in 1978, creating lake releases during low flow periods.

• The cities of Kenney, Clinton and Maroa all have either begun or increased the amount of effluent flow they discharge into Salt Creek.

• Meteorological has trended towards greater precipitation in the region, raising the amount of flow occurring during low flow situations.

Bottom line, the figures had changed favorably for the city, but not enough to not do something different.

Initially, it looked like one or two more clarifiers at a cost of $1 million to $2 million would need to be added in order to bring the water quality in line with what the stream can now support. The other option was to cut back on the plant operation. The amount of the cut back would mean no more additions to the system.

However, working with the new figures it was determined that the plant could derate the volume of water treated each day to an amount that would meet IEPA standards with no other changes. There will still be plenty of room for growth, other than if someone came in that used a ton of water, such as a slaughter house, Kitzmiller said.

[Jan Youngquist]