SABULA, Iowa — Against the backdrop of the Mississippi River, panic ensues every time Pam Brown gets on the Savanna-Sabula Bridge.

“My heart rate goes up just going across it,” said the Savanna, Ill. Chamber of Commerce executive director. “I pray I’m not going to meet a semi on my way.”

At just 20 feet wide, the half-mile long steel grate bridge deck that arcs 65 feet above the channel hardly has enough room for two lanes of motor vehicle traffic. Forget walking or riding a bicycle across it.

“I value my life,” Brown said, “so I wouldn’t do it.”

The Illinois Department of Transportation will debut an $80 million replacement in 2018. The new bridge is being constructed 100 feet downriver from the old one and connects Savanna with the island community of Sabula, Iowa. As of this week, crews had several of the piers up.

The 84-year-old, sky blue landmark served a useful purpose for a time in history after it was assembled by government workers and a local contractor during the Great Depression. But, IDOT officials say, it has become functionally obsolete.

Listed on the National Register of Historic Places, the slender, steel-truss original was designed by G.A. Maney of Minneapolis and completed by the Savanna-Sabula Bridge Co. in 1932 for $750,000. Initially constructed as a toll bridge, the toll was removed in 1987 after the construction debt was paid off.

Driving from west to east is an experience in contrasts. The Quad-City Times ( ) reports that the bridge carries U.S. 52/Illinois 64 over the river through a series of girder spans that gracefully rise from the Iowa side. But then driving through the three-span cantilever through trusses approaching Illinois gives the impression of heading into a caged dead end that smacks into limestone cliffs. The bridge actually ends in a tight T-intersection with Illinois 84 that, in periods of heavy traffic, leaves Illinois-bound vehicles wishing to turn right waiting high above the river.

The skinny bridge routinely accommodates big truck traffic, and Savanna Mayor Tony McCombie said she has to proceed with caution whenever staring down a semi-trailer.

“It’s narrower than a typical bridge,” McCombie said. “You have to go really slow when a semi is coming. It’s a steel grate compared to a solid surface floor, and it makes motorcycle riders a little leery. And the mayflies — we call them shadflies — can get pretty slippery on there.”

The bridge has attracted an average of 2,400 motorists a day as well as swarms of hatching shadflies every summer and at least one actor-celebrity in the 1980s — a scene from the made-for-TV movie “Hard Knox” shows Robert Conrad driving across it.

Patricia Perez, who grew up in Sabula and bartends at popular biker hangout Iron Horse Social Club in Savanna, remembered riding on the back of her father’s motorcycle crossing the bridge as a child.

“I’m usually not afraid of heights,” she said. “But when I went over the bridge and looked down, it scared me.”

The bridge intimidates local bikers.

“I hear it messes with their ability to ride,” Perez said. “Everyone’s first reaction is to drive down the middle, but you can’t keep the handlebars straight. Locals figure out riding close to the rail and let it glide you up. The arch will take you to the middle of the road.”

Since its construction, the bridge has faced numerous maintenance repairs and a major rehabilitation in 1985 prior to the state of Illinois taking over jurisdiction. A bridge inspection completed in August 2010 documented more than 100 deficiencies in the structure, according to an IDOT report.

“The entire 947-foot-long Iowa approach viaduct and 700 feet of the open-steel grate deck on the main river crossing truss spans are severely deteriorated and are beyond further rehabilitation possibilities,” the report states.

The IDOT report also stated that the design of the existing truss spans is “inherently fracture-critical,” meaning failure of “one or more of its members in tension would probably cause a portion of, or the entire bridge, to collapse.”

A report from the Illinois Structure Information System provides structure ratings on a scale of 0 to 9, with 9 meaning relatively new and 0 meaning closed to traffic. Based on a 2013 inspection, the Savanna-Sabula bridge rated a 4, which means “poor condition — advanced deterioration,” thus categorizing the bridge as “structurally deficient.”

The bridge is functionally obsolete in that the deck width is only 20 feet when 32 feet is required to meet current traffic standards and 40 feet is required to accommodate additional bicycle traffic, a 2014 IDOT report states.

The two-year-old report also states that the design of the bridge increases the likelihood of head-on crashes and sideswipes. IDOT obtained crash information from 2006-2012 and found that six crashes, including one fatality, occurred on the bridge and another 17 crashes happened on Illinois 84 near the bridge. The fatality was a sideswipe same direction crash that occurred while one vehicle was attempting to pass another.

The 2014 report concludes that replacement of the bridge “is the only viable long-term solution.”

Whenever the bridge closes, commuters are subjected to 50-mile detours. It is the only motor vehicle bridge between Clinton (a half hour drive south) and Dubuque (an hour to the north).

Tom Holman, owner of Bombfire Pizza in Sabula, said the replacement is a long time coming.

“Like seven years ago or so they came in, had meetings and threw some money at this bridge,” he said. “And they told us they would never, ever build us a new bridge because the traffic count was not high enough. … A couple of years ago, they said we’re getting a new bridge.”

Holman said the business community is “very excited” for the bridge, calling it the “biggest construction project” to hit the area in a long time.

The Sabula-Savanna area, Holman said, is a popular spot to cross the Mississippi for both motorists and bikers, especially in September and October when the leaves change color. A new bridge, he said, will be able to better accommodate them in addition to cyclists.

For some, the project is bittersweet.

Brown, who has lived in Savanna since 1961, attached two adjectives that, she thinks, best describe the old bridge: “beautiful” and “treacherous.”

But, she said, the beauty is purely aesthetic, and she looks forward to the new one.

“I’ll be sad to see the bridge go,” she said. “It’s a beautiful drive up here between Savanna and Sabula. But as a driver, it will be nice to have a better connection.”

Information from: Quad-City Times,

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