City of Springfield Pursuing IEPA Permit for Hunter Lake

In the latest round of the decades-long debate about Hunter Lake, many questions that opponents have asked for years are getting another look. An environmental study, which the city needs to complete to obtain a permit from the Army Corps of Engineers, will examine the need for a supplemental water source and determine the most cost effective and least environmentally damaging option to meet the need.

City of Springfield officials have emphasized that the second lake may not be that option. Still, in case it is, a water resource specialist hired by the city is developing a plan for how Hunter Lake could meet water quality standards and get another required permit from the Illinois Environmental Protection Agency.

“If Hunter Lake is the preferred option, we would design and build it so it would meet requirements and be sustainable,” said Jeff Boeckler, the principal water resource specialist with Northwater Consulting.

Springfield contracted with Northwater in January for around $209,000 to complete an anti-degradation plan, which is required to apply for the IEPA permit.

The agency preliminarily approved City Water Light and Power’s plan in 2000. But Brian Mohser, water quality standards section manager at the IEPA, said the agency has asked for a more expansive plan this time, particularly to address concerns about the nutrients nitrogen and phosphorus.

“If building the lake is (Springfield’s) only real alternative, then how do you keep that lake from violating water quality standards from excess nutrients?” Mohser said. “That was the one burning questions that we didn’t do a good enough job on last time.”

Environmentalists raised concerns about the second lake’s ability to meet these standards during a public comment period in 2008, when the city updated its permit application for Hunter Lake.

Extra fertilizer and soil erosion from surrounding farmland and runoff from storm water can cause higher levels of the nutrients phosphorus and nitrogen in lakes and streams. The excess nutrients feed algae, which, if there’s too much, create algae blooms that kill fish and can be harmful to humans, according to the U.S. Environmental Protection Agency. So, the agency has standards for how much of these nutrients can be in sources of drinking water.

The anti-degradation plan looks at ways to manage the watershed, the area surrounding the lake, to limit the amount of nutrients in the water. Most lakes in Illinois, including Lake Springfield, have excess nutrients because of decades of sediment buildup. Creating a plan to meet the standards before a lake is built is unique, Boeckler said.

“With Hunter Lake, we have an opportunity to deal with nutrient buildup before it happens,” Boeckler said. “To me, this is an extremely rare opportunity, to manage a lake and its reservoir before you put it in and being thoughtful before it’s built.”

The plan could include working with farmers on the land near the proposed lake to use fertilizer differently and limit how much gets into waterways or creating a wetland habitat that would naturally filter phosphorus and nitrogen out before it reaches the lake.

“(The plan) is going to be a combination of things,” Boeckler said. “We’re going to have to get creative with it.”

A new lake hasn’t been built in the state for decades. So, the cost of implementing a plan to keep sediment levels low is unknown, Mohser said.

“The city has a pretty good idea of how much it costs to build the lake, buy the land, build the dam,” Mohser said. “We’re just talking about the costs of alternatives to keep nutrients out of the lake to the best degree possible and maintain that through the life of the lake. Right now, that’s just an unknown amount.”

Clark Bullard, a retired engineer and board member of the National Wildlife Federation, says the cost of maintaining the new lake would make it a much less attractive option.

“If they built a lake that could meet standards, it would be very expensive,” Bullard said. “That’s something that will make the alternatives look even better.”

The latest price tag for Hunter Lake is $108 million. Even though the cost of managing the new watershed isn’t clear, there is enough of a cushion included that the overall price of the project should be close, said Ted Meckes, water division manager at CWLP.

“(The anti-degradation plan) is partly included in the estimate. Is it right? Probably not, but I’m confident it’s close,” he said.

CWLP has experience managing Lake Springfield’s watershed to limit nitrogen and phosphorus, using strategies that could be employed for Hunter Lake. The utility spends about $500,000 on watershed management every year, Meckes said.

CWLP and the Sangamon County Soil and Water Conservation District and other local organizations also get federal money to work with farmers to put in cover crops and build grass filter strips, among other strategies to reduce nutrients that flow into the Lake Springfield. Reducing sediment and nutrient buildup before it reaches the lake is important to do before dredging.

“Dredging is a very expensive process and one that unless you minimize what’s coming in, it isn’t effective,” Meckes said.

Dredging Lake Springfield is one of at least four alternatives included in the environmental study to meet Springfield’s future water demands. But, Meckes says, CWLP still has work to do on the watershed.

“We don’t have any plans to dredge in the next couple of years. We need to minimize what’s coming in. We probably have another three to four years of work in the watershed to do before that,” he said.

Decatur dredging

Springfield last dredged the lake in the late 1980s, spending $7.8 million to remove silt and sediment and regain about 650 million gallons of capacity.

A more recent example is Springfield’s neighbor Decatur. The city of Decatur started a six-year, $91 million dredging project on its lake in 2014.

“We investigated other water sources, kind of like Springfield is doing now,” said Jerry Stevens, Decatur’s engineering services coordinator. “The best option for us was to dredge out the lake we have now.”

Lake Decatur has a capacity of around 8 billion gallons, compared to Lake Springfield’s 17 billion. Removing silt and sediment from Lake Decatur will increase its capacity by around a billion gallons of water, Stevens said. Similar to Springfield, the city also is working on managing the watershed to limit how much sediment flows into Lake Decatur and reduce the need to dredge in the future.

For Springfield, the utility has examined dredging as an alternative to building Hunter Lake, Meckes said.

“(The estimate) was almost $400 million to $500 million to get the volume we needed for supplemental supply,” he said. “That would be not just removing sediment but removing original lake bottom to get deeper.”

Still, the Army Corps’ environmental study process will re-examine the needs and cost over the next year.

Source: SJR