Will gravel pits do the job?
Pump testing is needed. And Springfield needs a plan.
Allen Wehrmann, the head of the Center for Groundwater Science at the Illinois State Water Survey in Champaign, recently told Illinois Times that he’s not convinced that gravel pits, including the $875,000 Clear Lake Township gravel pit that the city council voted to purchase last week, could provide Springfield with its backup water supply.
“There’s a lot of lingering questions,” Wehrmann says. “It’s not simply, ‘I’ve got a bathtub full of water and we can just
The city should start monitoring water levels in the 148-acre gravel pit — a deep trench that holds water between spaces of sand and gravel — and groundwater levels in the flood plain to see how they respond to changing weather conditions. Pump tests are needed to determine if low stream and river levels also equal low groundwater and gravel pit levels and to identify what effect withdrawing water has on nearby Riverton wells.
“It’s a matter of trying to understand the resource better and how it’s going to act in a drought,” Wehrmann says.
He points to other factors that need to be considered, such as: Can 100 percent of the water in gravel pits be removed? If gravel pits are pumped down, how usable is the water at deeper levels? Would there be stability issues?
“It has some merit, but it’s not just a golden apple. It’s going to have its own associated set of concerns,” Wehrmann says.
Answering some of these questions won’t be easy. Wehrmann says the ISWS doesn’t have any extra funding to offer. The city — paying for the gravel pit with funds raised by 2008 bonds issued for water
infrastructure projects — hasn’t identified a funding source to pay for testing.
But Mayor Tim Davlin encouraged aldermen to approve the measure anyway. In addition to potential backup water, the mayor contended that the remainder of the 385.84-acre property, which lies along the Sangamon River at the former site of Clear Lake Sand and Gravel near Riverton, would provide a site to set up emergency dams during a drought.
“If we don’t own this, we’ll never have this chance again,” Davlin said at the Jan. 6 council meeting. “We don’t know who’s going to come and buy it next.”
Four aldermen — Frank Lesko, Mark Mahoney, Debbie Cimarossa and Frank Kunz — voted against the purchase. Kunz objected to sinking money into the gravel pit
without a clear heading. He warned that aldermen were “entering into just what city councils did…when they started Lake II and had no plan, no forward action to finish the job.”
Other aldermen who voted against the measure questioned why pump testing wasn’t done before the purchase and asked City Water, Light and Power how one gravel pit — estimated by the ISWS to yield 1.54 million gallons of water per day — would get the city to its drought demand.
“If you’re talking one pit, that’s something that we’ve never explored,” water division manager Tom Skelly said. “Is that your long-term water supply plan? It’s certainly not enough to fulfill the 9.1 mgd that we say we need. What’s the rest of the plan?”
In February 2008, Crawford, Murphy & Tilly, consulting engineers in Springfield, released a preliminary study of six Sangamon River Valley gravel pits and 14 nearby wells and their potential to provide a backup water supply. According to CMT, the six gravel pits, which include the Clear Lake pit, would yield 7.4 mgd and the 14 wells would yield 4.6 mgd. This would meet the city’s drought demand with a combined total of 12 mgd.
CMT states that the total capital cost of the design and construction of a water withdrawal system yielding 12 mgd from the six gravel pits alone would equal $47,536,518. This would entail transferring water from a permanent pumping station located at the edge of each gravel pit to a storage tank located nearby, then on to Lake Springfield.
John Homeier, founder of Bi-Petro, a Springfield oil company, owns the 19-acre Sang-Chris gravel pit and 90 acres of the 288-acre Buckhart gravel pit. He says the Clear Lake gravel pit purchase was a good start, and combined with his gravel pits, the city could meet its water need.
Homeier disputes the CMT data, which estimates the Sang-Chris gravel pit to
yield 0.14 mgd and the Buckhart gravel pit to yield 2.13 mgd. Instead, he
claims that the gravel pits contain an endless supply of water. He says they’re constantly replenished by three sources: a 45-billion gallon aquifer that
runs south of Riverton to Illiopolis; the north fork of the Sangamon River,
connected to the aquifer; and underground water movement from east to west.
“You can never pump these lakes down,” Homeier says. “I tried to pump one down one time. I pumped on it for a month-and-a-half, and I couldn’t even lower it one inch.
“And when the river drops or raises, it drops or raises.”
Homeier also suggests that he could transfer water from the gravel pits to the
city’s water treatment plant for much cheaper than CMT estimates — $20 million at the most — by installing pumps on electric-powered pontoons.
“When a drought comes, slide them on the rail, put them in the lake, connect your
pipeline, turn an electric switch — and you’ve got water,” Homeier says. “When it floods, roll them back out, and put a cloth over it.”
Ninety-five percent of the required 8.5-mile pipeline could be installed along county road right-of-ways, he adds. It could be operational within 12 months.
Wehrmann says the ISWS proposed to pump test Homeier’s gravel pits, but it never came to fruition. As with the Clear Lake Township gravel pit, he continues, the ISWS needs more information before it can support Homeier’s claims.
Contact Amanda Robert at firstname.lastname@example.org.