A handful of little changes to Washington’s newest ferry are costing big bucks for a design flaw.

Anyone who has been on the 144-car Tokitae between Clinton and Mukilteo lately may have noticed a slight change to its upper deck ramps. The Washington State Department of Transportation, Ferries Division started work on temporary modifications to the ramps last week, adding pieces to keep cars from bottoming out. At the top, the metal trapezoids reduce the angle for cars transferring from the ramp to the deck.

Cars with low clearances were reportedly scraping as they were sent to the second-level car deck. Once the problem was identified, Washington State Ferries workers were tasked with sending vehicles with higher clearances to the top and keeping cars, mostly sedans, on the bottom.

Potential problems with the ramp design were raised by state legislators after hearing from ferry workers in February, months before the Tokitae went into service. State Rep. Norma Smith, R-Clinton, after learning that cars indeed were bottoming out on the Tokitae, called for an immediate fix and massive changes in ferries leadership.

“The ramps are simply systematic of what we’ve been dealing with since as long as I’ve been in the Legislature,” Smith said Friday in a phone interview.

“It shouldn’t have been that difficult when your crew members … are giving you feedback on operating performance,” she added. “The management needs to listen and weigh it carefully.”

One Tokitae crew member said the plates are working, confirming a ferries division news release. Shane Thrasher said during a Friday morning sailing from Mukilteo that the Tokitae’s crew is able to load the boat the same as others, without sorting cars as diligently based on their undercarriage.

Cost estimates for the design, fabrication and installation of the eight prototype inserts for the Tokitae total $66,000. Another $100,000 is figured for the permanent installation, which will be done in December when the Tokitae is pulled out of service for a scheduled maintenance period. All of the money spent on fixing the ramps will be covered in the contingency of the original contract with Vigor Industrial.

The temporary plates were installed to simulate the transition without cutting into the ferry’s structure.

The new ferry will dock at a new location in a few years. In late August, Washington State Ferries received the Federal Transit Administration’s Record of Decision about the proposed new Mukilteo terminal.

An open house about the project and its environmental impact mitigation and construction is scheduled for 5:30-7:30 p.m. Wednesday, Oct. 8 at the Rosehill Community Center, 304 Lincoln Ave., Mukilteo.