The final bid package for Oak Harbor’s sewage treatment plant came in with a price tag millions of dollars more than expected — again.

If council accepts the bid, it will raise the ever-escalating, estimated cost of the sewage treatment plant to $147 million.

Oak Harbor staff members unveiled the bid results during a special city council workshop Wednesday. Council members had a series of questions and comments.

“I’m mainly concern about this $7 million,” Councilman Jim Woessner said, referring to the cost of the bid over the estimate, “because reality is it’s now putting us $27 million over on the cost of the sewage treatment plant.”

The increasing cost of the sewage treatment plant has been an ongoing concern for city officials. Oak Harbor Mayor Bob Severns announced in February that the estimated cost of the sewage treatment plant jumped by $20 million — from $122 million to $142 million — in just 15 months. Severns said he was going to hire an outside firm to review the project and the costs.

The sewer plant is being built through a process called general contractor / construction manager, or GC/CM. Under the process, the city bids out a series of packages, or a “guaranteed maximum price” contracts, for different work throughout the project.

The final package, GMP 13, mostly contained work involving Windjammer Park, which has been torn up because of the ongoing construction.

The funding for the project is divided into two categories. Since the city is obligated to restore the park to its pre-construction state, that work is considered part of the larger project and will be funded through sewage treatment fees that users pay. The other is optional projects that would be funded through the general fund.

The bid for the sewer-fund work is $12.4 million and the general-fund work came in at $6 million. An earlier estimate, however, put the total cost of both at $10-$15 million, City Engineer Joe Stowell said.

“So we blew that bid by $7 million,” Woessner pointed out. “It’s over double the engineer’s estimate.”

The fact that the bid came in higher than expected means that the optional part of the project may have to be pared. Staff members proposed that the general-fund project be limited to a splash park, hardscape, landscaping and electrical work.

But even paying for that might mean dipping into the city’s stability fund, which is set aside for emergencies. It’s earmarked at 25 percent of the city’s general fund budget and is currently at $3.8 million. About $600,000 would be needed.

The features that wouldn’t be funded are a kitchen building on the west side, a pavilion structure and a maintenance building. City staff applied for grants from the Island County economic development fund for the kitchen, which would cost $1.2 million, and pavilion, which is nearly $700,000. Staff members said the maintenance building will likely have to be foregone.

The council members seemed to agree with the staff’s proposal. The bid package will be on the April 17 council meeting agenda for possible acceptance.

Still, council members questioned some of the bid results.

Councilwoman Erica Wasinger asked how a kitchen could cost more than a million dollars. Stowell said calling it a “kitchen” simplifies what it is, which he described as “an industrial structure” that has to withstand the elements on the waterfront.

Woessner asked why the estimates were so far off base. Stowell said part of the reason is that they didn’t include the demolition of the former Whidbey Island Bank building, which is about $500,000, as well as some smaller work.

Still, Woessner asked if it was normal to have bids come in twice the estimate. Stowell conceded it wasn’t.

The effect the latest cost increase will have on the sewer rates will be minimal, according to the latest estimate. The monthly rate had been projected to increase to $110 in 2021; the latest estimate pegs it at about $112 a month in 2021.