The state is moving ahead with a plan to replace the Frank J. Wood Bridge that connects Brunswick to Topsham following a federal determination that it would cost more to fix it than to replace it.

Built in 1931, the bridge is rated in poor condition and must be inspected every six months, according to the Maine Department of Transportation. In a Tuesday press release, the department said it plans to advertise for construction bids for the replacement of the bridge later this summer or early fall and that construction would begin later this year.

In 2017, the department estimated the bridge project would cost $13 million, an estimate that has now ballooned to $33.5 million.

The department said it will post a Federal Highway Administration draft finding on Wednesday that confirms its cost estimate. Comments on the finding will be accepted until Aug. 26.

“The Federal Highway Administration has again confirmed what we have long known to be true: that the safety, reliability, and cost-effectiveness of our new bridge plan is the best solution,” Bruce Van Note, Maine transportation commissioner, said in a statement. “State and federal agencies with the responsibility for this bridge crossing, as well as local officials, have determined that our new bridge plan is solid.”

The new bridge will have sidewalks on both sides, parks on both ends and views of the Pejepscot Falls site. It will also be bike and pedestrian friendly, according to the department.

When asked why the federal document cannot be released sooner, a Maine DOT spokesman said via email that “we’re posting it tomorrow.”

A spokeswoman for the Federal Highway Administration said she would have to check with Maine officials about the document. The Friends of the Frank J. Wood Bridge, which has opposed the state’s effort to replace the span, did not respond to a request for comment.