URBANA – Ameren Illinois officials have begun winnowing the number of options for a new high-voltage transmission line, built with 75- to 100-foot-tall structures, that would connect a substation near Bondville with another on the southwest side of the University of Illinois campus.

Utility company employees met Tuesday afternoon with local officials to discuss the route for the transmission line and will hold an open house from 4 to 7 p.m. Monday at the Urbana Holiday Inn, 1003 Killarney St., U. At the open house, Ameren officials will meet one-on-one with customers to discuss the project and the potential routes the 138,000-volt transmission line could take.

Ameren officials said Tuesday that the straight-line distance between the two substations is about 5 to 6 miles. But the various routes being discussed are anywhere from 8 to 17 miles long.

The shortest route, which would run south on Rising Road to Curtis Road, then east on Curtis to Neil Street and north to the southwest campus substation, would be about 8 miles long.

"But that does not mean we're going to build that," said Ameren spokesman Leigh Morris. "That does not even mean that's going to be a proposal. We're not even in any position to think about that yet. We've got to get through today's stakeholder meeting and Monday's open house before we can begin ... that distillation process."

The utility will suggest two or three potential routes to the Illinois Commerce Commission next January. The ICC has the ultimate decision and could even order a route not suggested by Ameren, Morris said. The transmission line is expected to be in operation by early 2014.

Current electrical industry figures show it costs an average of about $1.8 million per mile to build a high-voltage transmission line, according to Ameren.

"You want as few zigs and zags as you can," Morris said, "because the more that go in there, that creates engineering issues. The folks in finance don't want it because that adds to the cost of the thing. And then the people who maintain them, they don't want them. So you want to have as few bends and turns as possible."

He said the $1.8 million per mile cost "could easily become $2.5 million if there are a lot of turns," or more poles.

He also said building an underground transmission line was out of the question because it would cost at least 10 times more.

"They'd have to be very deep underground," Morris said. "There's a reliability issue. It costs more to maintain underground. It costs more to construct underground."

Ameren has no underground transmission lines anywhere in its system in Illinois or Missouri, Morris said.

"You do not do underground for reliability," he said. "That is not a reason. It's only done for aesthetics.

"It does not enhance reliability whatsoever."

The new transmission line is being built to meet electricity load forecasts that show annual growth rates for the next five years of more than 3 percent in southwest Champaign, according to Brian Anselmo, an engineer with Ameren.

"There's a number of reasons for the growth. It's new businesses and residents coming to the community. It is the continued growth of electrical devices." Morris said. "Turn on your big-screen TV set, which uses more electricity than your old one did, and you can see all the stuff that gets advertised. And who knows, you may be plugging a car into your outlet at home one day."

The utility said the line also would allow for more reliable service to Champaign-Urbana and would improve the company's ability to perform system maintenance.

Morris said the high-transmission line in most cases would not be noisy, create radio or television interference or kill birds.

"Yes, you can pass under power lines with an AM radio, and sometimes there can be interference," he said. "But it's only right underneath the line, and we don't build lines over houses. We don't build lines over hotels. We don't build them over any place where people could be living."

More information about the transmission line project is available at the Ameren Web site, http://citransmission.com/go/site/2108/.