Water-Supply Planning

Studies, Law Could Whet Appetite for Infrastructure, Green Upgrades

by Craig Barner

Infrastructure and sustainability in Illinois could get a boost from planning and a new ordinance aimed at ensuring adequate water supply and quality.

The Regional Water Supply Planning Group, a state-funded organization in Northeast Illinois, is exploring conservation measures, including improvements to water infrastructure.

Also, an ordinance that went into effect in Chicago in January to minimize the negative effect of stormwater could prove a boon for suppliers and installers of pervious materials and green roofs.

Water-Supply Pressure

Planning the water-supply is needed, says Kay Whitlock, vice president of Rosemont-based Christopher B. Burke Engineering Ltd. and president of the Illinois section of the American Society of Civil Engineers.

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“We have had the luxury of not having to consider water supply in our development plan, but we’re coming to that spot where we have to,” she says.

Without planning, the strain on the water system could intensify in part because of an expected increase in population, says Timothy Loftus, senior environmental planner for the Chicago Metropolitan Agency for Planning, a group formed in August 2005 through the merger of the Chicago Area Transportation Study and the Northeastern Illinois Planning Commission. Northeast Illinois’ population is projected to grow by 2 million people by 2030 and another 2 million by 2050.

Adding to the pressure is a consent decree issued by the U.S. Supreme Court limiting the amount of water that can be removed from Lake Michigan by Illinois.

The lake is critical to the region because it supplies about 77% of the drinking water, Loftus says. The rest is withdrawn from the Fox and Kankakee rivers (5%) and deep-bedrock aquifers (18%). And, evidence is mounting—higher levels of arsenic, radon and salt than in the past—that water is being extracted from the aquifers at a level that exceeds the recharge rate, Loftus says.

Adding to worries are prolonged droughts, mounting evidence of climate change and declining lake levels.

The stress on supplies is being mirrored in the systems to deliver and take away water. The infrastructure for drinking and wastewater each received D- letter grades in the ASCE’s Report Card for America’s Infrastructure in 2005, the most recent, and had declined from Ds each in the 2001 report card.

“We’re concerned about the conditions of infrastructure and its capacity to serve,” Whitlock adds.

As a result of concerns, Democratic Gov. Rod Blagojevich signed an executive order requiring the Illinois Department of Natural Resources to lead state and regional water-supply planning and provided $5 million in funding. CMAP is leading planning in Northeast Illinois and received $1.1 million to form the Regional Water Supply Planning Group. A similar effort is being overseen by the Mahomet Aquifer Consortium in Central Illinois.

Weighing Water Management

As part of its water-supply study, RWSPG is weighing 14 water-management practices from the Sacramento-based California Urban Water Conservation Council.

“We still have to work out the language, but the [RWSPG] has agreed to implement conservation measures at a level the region hasn’t done before,” Loftus says.

From the perspective of construction, the key recommendation is for water-system audits, leak detection and repair. The need to replace aging water pipes was underscored in January when an 80-year-old water main burst in Chicago’s Ravenswood neighborhood on the city’s North Side, opening a 25- by 50-ft sinkhole and spouting instant rapids on Montrose Avenue.

Tom LaPorte, spokesman with the city’s Department of Water Management, says that only 22 mi of the 4,300 mi of water pipe in the city were replaced in 2007. Much of the city’s system of water infrastructure is approaching a century of use.

“Some of those pipes are beyond their useful life,” Loftus adds.

Thirty-three delegates representing 10 stakeholder groups form the RWSPG. They hold monthly deliberations on water-supply planning for the 11 counties in the region, Loftus says. The first meeting was held in January 2007, and recommendations on planning should be finalized in June.

In addition to making recommendations on water conservation, other plans include doing a water-demand analysis and conducting education and outreach.

“Traditionally, the way the country has evolved was to build more reservoirs and build more dams, but that’s not the option it used to be,” Loftus says. “In the 21st Century the emphasis is on becoming more efficient.”

Boost to Sustainability?

Efficiency was also the goal of the Chicago City Council in the fall when it passed a stormwater ordinance designed to minimize the negative impact of new development and redevelopment on stormwater.

The measure requires new developments or redevelopments of certain sizes to capture the first .5 in. of runoff from impervious surfaces, such as roofs and parking lots, instead of allowing it into sewers, says John Spatz, commissioner of the Chicago Department of Water Management. The first .5 in. often carries the most pollutants.

Sustainability could get a big boost. The requirement can be met by installing green roofs, permeable pavement, cisterns or bioswales, Spatz says.

“More pervious materials will be installed for sure,” he adds.

The ordinance can also be met by reducing the amount of impervious area by 15%.

The law applies to any development or redevelopment exceeding 1,500 sq ft (about four city lots or more) or contiguous area at grade exceeding 7,500 sq ft, which is normally a parking lot with about 20 spaces.

The benefits of the ordinance include reducing or delaying stormwater volume, enhancing groundwater recharge and reducing urban heat.

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