The public park, located on the citys west side, includes the citys skate park, a baseball diamond, a childrens playground, a large grass picnic area and the nonprofit Pioneer Museum off Riverside Avenue.
The work contract includes plumbing and electrical repairs as well as disabled access improvements and a new roof.
Four employees from C3 Construction will do the project plus three subcontractors for electrical, roofing and painting, C3 Construction principal Andre Lekai said.
Volunteers originally built the parks restrooms in the late 1970s, according to the city. In March 2011, the City Council approved a volunteer project by local service club Noontime Kiwanis to remodel the restrooms.
The clubs volunteers were ultimately unable to do the work, so the restrooms were closed in June 2012 and the city sought a professional repair contract, Public Works Director Doug Monn said.
At $49,521, C3 Construction submitted the lowest of 11 bids submitted to the city on Oct. 25 and was awarded the job in November.
With a 10 percent contingency fund, the project will cost $54,473 from the citys general fund, according to the city.
Construction is slated to be complete by the spring if weather permits.