By Eric Freyfogle and Clark Bullard
For most residents of the Champaign-Urbana area water comes from the faucet and there's little reason to think of it so long as the water flows. This too-common attitude needs to change, and soon. In fact, our region is overdrawing its principal water supply, in the process lowering water tables and degrading rivers.
At the same time, we are showing keen interest in diverting sizeable water flows to new industrial users, worsening long-term prospects and reducing future options. The time has come for government leaders to step in and deal with our deteriorating water situation, putting an end to the piecemeal decision-making that has led us to where we are.
For starters we need to say no to a proposed sale of treated wastewater by the Urbana-Champaign Sanitary District, water that we could better use to meet local water needs and to remedy the ill effects of already-excessive withdrawals.
Most of the county gets water from a water-filled sand formation some 250 feet beneath the land surface, known as the Mahomet Aquifer. From this large reservoir of water we draw 33 million gallons per day, and rising.
Decades ago we knew little about this aquifer. Today we know far more, thanks to invaluable work by the Illinois State Water Survey. And what we've learned is troubling.
We now know that the natural flow of water into the Mahomet Aquifer is only 5 million gallons per day, far less than what we extract. That inflow is matched by water moving westward out of the region, pulled by gravity.
Thus, before our pumping began, 5 million gallons of water entered and departed the reservoir daily. Today, due to our withdrawals, far more water is drawn into the aquifer to offset our extractions. Some 27 million additional gallons of rainwater per day enter the aquifer from above, and an additional 3 million gallons percolate upward from deeper limestone formations. This inflow of 30 million gallons leaves a daily shortfall of 3 million gallons — the rate at which we are lowering the aquifer's level.
Our problem is not simply this 3-million-gallon daily overdraft. It is also the 27 million gallons of rainwater drawn into the aquifer by our pumping, water that would otherwise flow into rivers. Less rainwater runs directly off the land surface. And less water percolates into shallow sand aquifers and from there into rivers.
In one way or another, pumping reduces river flows by 27 million gallons per day. Much of that water would have reached the Sangamon River, serving downstream needs and sustaining aquatic life.
Declining groundwater levels and reduced river flows are gravely troubling. Just ask Decatur residents, who face significantly increased water rates to find water from elsewhere. (The Sangamon River in Allerton Park was dry for 40 days during the summer of 2012.) Lower water flows harm aquatic life, impair human uses of rivers, and concentrate pollutants, making it more difficult to meet water-quality standards. Farmers suffer during dry periods as water tables fall beneath plant roots.
Meanwhile, pressures for greater withdrawals are on the rise. Recent droughts have led farmers to install massive irrigation equipment.
Water-intensive industries in Vermilion and Douglas counties are seeking long-term contracts to divert our treated wastewater. The Champaign-Urbana area is, in fact, a place of water scarcity. But we don't yet know it and haven't taken steps to protect and manage our waters sensibly.
In our view, our water-use patterns should be guided by several key principles.
1. The Champaign-Urbana area should act responsibly toward other communities and future generations, sustainably using only our fair share of water.
2. Similarly, we should use water only in ways consistent with the maintenance of the ecological health of our rivers, for the benefit of people and all life.
3. We need to realize that surface waters and ground waters are connected and to think of water flows in systemic terms. At the same time, we need to show respect for surface watershed boundaries, minimizing diversions of water from one watershed to another (for instance, from the Sangamon to the Vermilion or Kaskaskia river basins).
4. Necessarily, this means system-wide study, planning, and management, considering all aspects of water flows from initial withdrawals through the disposition of return flows.
Excessive pumping can be addressed in two obvious ways: by pumping less and by re-using more.
Our treated wastewater could itself be a local water source (as it is in many water-limited areas), particularly for agricultural and industrial users. It could also be used to recharge the Mahomet Aquifer.
This could be done by discharging it into floodplains of the upper Sangamon River, where much of it would percolate into the aquifer.
The Champaign County economy supports 2,500 jobs with every million gallons of water we pump daily. The sanitary district's proposed sale to a water-intensive Tuscola chemical plant would support only 25 jobs for the same million gallons. We should keep our water here where it can produce more economic benefits.
What is needed? We propose that mayors and county leaders assemble to address this issue, assessing the situation, setting principles and goals, and developing plans for action. We look to government leaders for action because we have little hope that an assembly of "stakeholder interests" would lead to anything more than bickering over water shares. Water planning must be guided by a vision of the long-term common good. Seats at the table should be limited to leaders committed to that vision and accountable to voters.
Under longstanding Illinois law all water in the state is owned by the people collectively with government obligated, as trustee, to manage it for the welfare of all. The time has come for our leaders to act on that duty.
Eric Freyfogle and Clark Bullard are, respectively, professors of law and engineering at the University of Illinois at Urbana-Champaign.