The Humboldt City Council would like some aesthetic enhancements for the new Sumner Avenue Bridge. Now, it’s just a question of what and how much.
The council heard a report from Stan Stallsmith, senior structural engineer with WHKS and Company, an engineering firm in Mason City, who provided a preliminary design report on bridge structures to the Humboldt City Council two years ago, but the project was stalled because of funding restraints.
Stallsmith gave his report at the council’s regular bi-monthly meeting, Tuesday, Feb. 19.
The three-span, concrete spandrel arch bridge that crosses the Des Moines River at the west entrance to downtown Humboldt was constructed in 1920, so it is now more than 90 years old. The length of the bridge is 244 feet with two spans of 78.5 feet and one of 87 feet.
Stallsmith said the Humboldt City Council can determine the aesthetic level for the bridge in the next few months, after which preliminary design plans will be finalized. Stallsmith told the council that the final design for the new bridge should be ready by the end of this calendar year, so bids can be taken and deconstruction of the old bridge and construction of the new bridge can begin in the spring/summer of 2014.
Stallsmith showed the council members examples of different bridges, from ones with no aesthetics, to ones with rusticated concrete, ornamental railings, pedestals, special lighting and surface finishes.
The engineer told the council that aesthetic enhancements typically fall into the categories of 1-5 percent of the total structure cost, 5-10 percent, or 10-15 percent. The cost of the bridge replacement is expected to be $2.3 million. The city will be receiving a $1 million grant from the Department of Transportation to help with the project.