Francis C. Klaas, Kendall County’s longtime engineer, cuts a ribbon to mark the opening of the Eldamain Road bridge over the Fox River between Plano and Yorkville. The bridge is named in honor of Klaas, who guided the project since the early 1990s. (Chronicle Media photo by Jack McCarthy)

Kendall County’s first bridge over the Fox River was constructed in 1851 in Oswego for the then princely sum of $2,250. It lasted just six years before being washed away in a flood.

The county’s newest Fox River span — the $35 million Eldamain Road crossing — is expected to be much more durable.

An imposing, yet sleek two-lane steel and concrete bridge, located along municipal borders dividing Plano and Yorkville, was formally dedicated and opened to traffic on Wednesday, May 31.

It is named for Francis C. Klaas, county engineer since 1991 and guiding light since the project’s inception.

“He’s the longest-serving county engineer,” said Matt Kellogg, Kendall County board chairman during ceremonies on a sunny and steamy afternoon. “It’s important as we look at county engineers and what they do, they develop long-range plans for transportation. We’re not talking five-10 years from now, we’re looking 50 years out and how to do things like this.”

Klaas cut the ribbon to open the bridge, witnessed by more than 100 people at the dedication ceremony.

It offers a new north-south route for county drivers as well as a connection between Illinois Route 71 and U.S. Route 34, both important east-west county roadways.

The bridge is also expected to spur economic development as well as divert heavy truck traffic from Illinois Route 47, which runs through downtown Yorkville.

The span is Kendall County’s eighth Fox River crossing and first since an Orchard Road bridge opened in Oswego in 2001. It is the longest ever built in the county, checking in 1,557 feet. The bridge consists of seven piers, including one in the Fox River.

The completed project features a two-lane roadway for vehicles — with the option to add two more lanes. There’s also a protected pedestrian and bicycle path.

New traffic signals have been installed at intersections at Route 71 and River Road while Kendall County’s first roundabout debuts at Fox Road.

According to county figures, the overall Eldamain Road extension project from U.S. Route 34 to High Point Road covered 4.75 miles and cost more than $50 million, including design, construction and land acquisition.

And it all came in on time and on budget.

“We built the whole thing in less than 30 months,” Klaas said. “This is obviously a very big project for us and such a long time in the planning … Engineers have a little bit of a technical term for when a big project comes together in a good way and that technical term is ‘pretty cool.’”