PRB Articles


Closing the Gap

The year was 1865 and Robert Tinker, employee for the Manny Reaper Company (a local farm implement manufacturer) had just returned from a company sponsored world tour. Inspired by his travels, Tinker decided to build himself a new home – one styled after the cottages he had fallen in love with in Switzerland.

As so often happens with projects inspired by passion, destiny (or cupid) got involved and Tinker found himself breaking ground for his new Swiss Cottage high on a limestone bluff overlooking Kent Creek and, on the far bank, the Manny Mansion, home to his employer, Mary Manny.

Five years later, Tinker and Manny were an item, engaged to be married, separated only by this pretty, bubbling creek. Being a man of the world (and possibly a little eccentric), Tinker constructed a swinging suspension bridge to connect his estate and hers. And the rest, as they say, is history.

Gully Washer

Well, almost. The bridge, originally constructed in 1870, was built on a slant, sloping down from the bluff to the north creek bank and putting it square in the path of the great flood of 1890 which swept through Rockford wiping out every bridge in town.

Undeterred, Tinker re-built the suspension bridge the very next year this time making sure to raise the support piers on the north side to level the bridge and put it out of reach of future floods.

Tinker’s bridge beat back the sands of time and weather for 86 years during which time his wife died. Her estate was sold to the railroad and her mansion, just across the bridge was razed to make room for additional rail yards.

Not satisfied with the view, Tinker, ever the visionary, convinced the railroad to allow him to build and maintain elaborate gardens on their side of the creek. This combination of elaborate gardens, suspension bridge and a unique Swiss Cottage sitting on a beautiful limestone bluff high overhead was the first thing visitors to Rockford saw as they exited the train depot upon arrival.

It was stunning – and the bridge was the central element. Beloved by the citizens of Rockford it became a local landmark and the Cottage entered the National Register of Historic Places.

In 1976, time finally caught up with the old, deteriorating structure and it was torn down.

Immediately, the Tinker Swiss Cottage Museum board of directors began talking about how they could work with the Rockford Park District (owners of the building and grounds) to rebuild the bridge.

The 29-Year Odyssey Begins

For 17 years, the museum board and park district talked, planned and organized. Then, in 1993, they caught a break. Having applied for and won a federal enhancement funds grant (80% federal money, 20% park district money) coordinated by the Illinois Department of Transportation (IDOT), the engineering and construction process began. Little did anyone know, it would be 13 more years before the bridge would be finished.

Jim Reid, Senior Manager of the Rockford Park District (a special district who’s oversight includes four cities, one of which is Rockford,) says the biggest challenge to the project was simply securing the appropriate approvals from all of the agencies involved.

“The state of Illinois had control of everything,” says Reid. “This was federal money, through the state of Illinois that was passed through the Illinois Department of Transportation for enhancement projects.”

Which meant, Reid and his army of consultants had to receive approvals from the Illinois Historical Preservation Department, the Illinois ADA Compliance Department, the Bridge Division of the Illinois Department of Transportation, the Army Corps of Engineers, the Illinois Department of Waterways and so on.

“At one point,” Reid says, “our consultant told us he counted over 20 approvals, from very small to very large, waiting for approval so we could go to bid.”

Retro Engineering

The process was further complicated by the Tinker Swiss Cottage Museum’s desire to stay as true to the original bridge’s design as possible. A tough task when you have to meet today’s safety and design standards.

“We worked with Willett, Hofmann & Associates (WHA) to make it look as much like the original as possible,” says Laura Bachelder, Executive Director of Tinker Swiss Cottage Museum. “And the real challenge was to try and give it some of the movement it originally had. It was not a bridge that stood stock still.”

The bridge’s original superstructure consisted of a timber deck and timber stringers suspended by timber transverse members and steel cables, without a railing. Not necessarily a safe structure and one that was often described by those who remember crossing it as a “swinging bridge.”

The folks at WHA began by determining the bridge’s original layout and dimensions. All that remained of the original structure was the south abutment, south suspension towers, and center pier and north and south dead man cables. Using photographs provided by the museum and their own survey information, WHA was able to determine the space and size of the original suspenders and transverse members as well as the deck width.

It was then the project hit its first real snag. The deck grade of the original structure was found to be 8 percent. Which is significantly above the 5 percent maximum grade allowed under current accessibility codes. After nearly a year of conversation and discussion, a compromise of 6.5 percent was reached.

While the accessibility issue was being discussed, clearing a second hurdle was underway. There was no handrail on the original bridge, but modern safety standards demanded one. After researching a variety of cable rails, WHA found they could run a small diameter tension cable through the suspenders in the south span and through the slender steel posts matching the diameter of the suspenders in the north span to act as an inconspicuous handrail. The spacing of those cables would meet current requirements for child safety, be strong enough to handle current horizontal load requirements and also be difficult to see when viewing the profile of the bridge – thus maintaining the original look. And on and on it went. Floodplain? Check. Pier support? Check.

Finally, in August of 2004 the approved design went out to bid with construction beginning in October. On June 9, 2005, Tinker’s Bridge held it’s dedication ceremony and two days later it was opened to the public – just 135 years after the first bridge was constructed and 29

years after it was taken down.

Somewhere, Robert Tinker and his wife Mary are smiling. Imagine how they’ll feel when the park district restores his famous railroad gardens and constructs a bike path along the north side of the river?

Managing In Micro

University Park

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