Efforts to raise nearly $2.3 million for the restoration of the Jackson Street bridge over the Raccoon River are in the homestretch.

Des Moines Park and Recreation Director Ben Page said a $500,000 contribution that was pledged in recent weeks from a group consisting of three people has brought fundraising efforts to within $550,000 of the target. So far, the donors have asked to remain anonymous, he said.

The bridge was closed to pedestrian traffic in 2013 over concerns about its load-bearing capacity. An early estimate of nearly $4 million to shore up the bridge led the Des Moines City Council to earmark $750,000 for its demolition.

Meredith Corp. funded another study that placed repairs and environmental remediation to trap lead-based paint at about $2.3 million. The bridge width would be reduced to 12 feet from 22 feet by installation of a wall, Page said.

The City Council agreed to provide the $750,000 for restoration, and the state of Iowa approved $500,000. The annual Mayor’s Bike and Run raised an additional $10,000 this year.

The closing has blocked a key connector from Principal Park to Gray’s Lake on the Meredith Trail. A committee of prominent business and city officials has led efforts to raise funds for the restoration. The Community Foundation of Greater Des Moines holds the account for donations.

Page has set a “soft target” of July 1 to raise the funds with hopes of beginning work during the 2016 construction season.

Since opening in 1898, the bridge has carried a load of wagons, vehicles, pedestrians and bicycle riders under various names, including the Southwest Fifth Street Bridge and the Green Bridge. It has been listed on the National Register of Historic Places since 1998.