A new style of vessel proposed for the Alaska Marine Highway System has received much scrutiny for the use of an open car deck.

Alaska Department of Transportation and Public Facilities Deputy Commissioner Reuben Yost addressed this feature and others of the state’s proposed Day Boat Alaska Class Ferry Wednesday at the Southeast Conference Mid-Session Summit.

Alaska Department of Transportation and Public Facilities released a draft design for the new ferry design Monday. If the project stays on schedule this design or a similar one could begin construction in early 2014.

“What we are looking at is a … deck that in the stern is partially open,” Yost said. “The point is to get ventilation to the car deck.” He said the open deck would have “minimal or no impact to vehicles.”

As currently designed, of the 53 vehicles the day boat carries, 30 would be under cover inside the ship.

An open deck design saves costs on the ship’s HVAC, heating and ventilation systems, Yost said. He said designers are trying to avoid an airtight structure. However, DOT plans to consider both covered and uncovered designs before selecting a final plan. Yost gave an example of potentially using a lightweight aluminum cover.

Opponents of the open-deck design say vehicles could be damaged by freezing sea spray thrown up by intense weather that often hits Lynn Canal in the winter. The new design replaces a much larger 350-foot Alaska Class Ferry design introduced in 2006. The state should return to this original design, some opponents have said.

Schematics of the proposed vessel show a mid-ship superstructure housing the wheelhouse and crew area and upper passenger cabin.

The passenger area would not extend most of the length of the ship as in AMHS’s other ferries. Instead the aft half of the ship is made up of bulwarks that extend 24 feet up from the water line with the roll-on-roll-off car deck inside.

Yost said the tall bulwarks should help prevent some sea spray from reaching vehicles. Another precaution against Southeast weather is designed into the bow, he said.

The new ferry would have a North Sea type of flared bow, “A bow that is designed to minimize freezing spray that could cause safety problems,” Yost said.

The vessel gets its “day boat” description from its daily 12-hour service window. This requirement saves costs in construction and operation as the vessel does not need crew quarters and the crew can return home after each shift. It also is what set the requirement for a quick-loading car deck.

Current AMHS ferries require ferry staff to rearrange vehicles as the ferry moves from port to port. The bow to stern roll-on-roll-off deck would offer a straight shot through the vessel to a set of clamshell doors in the bow. These doors would also speed offloading as they can be opened while the ferry approaches the dock.

Speed is particularly important for the service between Juneau, Haines and Skagway, where the 12-hour schedule allows only one hour in port, Yost said.

“We have to be able to tie up the vessel quickly and unload quickly,” Yost said.

These changes could cut the round-trip time from Juneau to Haines by five hours, “Compressing the operation into 12 hours instead of 17 hours,” Yost said.

Vehicles would load in Juneau at 7:30 a.m. and the vessel would return at 6:30 p.m. — in comparison to the current return time of 11 p.m.

Yost said DOT was tasked with the design and construction of the next generation of Alaska’s ferries. He said the idea is to build the ship the state will need for the next several decades.

“Any time you build a new vessel you have an opportunity to make a change in the system,” Yost said. “Once built it is difficult to change the operation of a vessel. We need to take a really close look at cost. Can we reduce cost without reducing service?”

The Roadmap design vessel is expected to replace the M/V Malaspina in Lynn Canal. As such, its design calls for seakeeping abilities similar to the ferry M/V Taku.

“We want to be able to go in all weather except the most extreme weather,” Yost said.

Yost said DOT also plans to take another look at Lynn Canal weather.

“We’ve heard from folks that past weather modeling of Lynn Canal is insufficient,” Yost said. “We will be doing more detailed study.”

Conceptual designs for the vessel show an overall length of approximately 280 feet. Two 3,000 horsepower marine diesels push the ship at about 16 knots using 85 percent power. The ship should hold a minimum of 53 Alaska Standard Vehicles – 21 feet long – and 300 passengers.

The upper-most deck could house the wheelhouse and crew lounge. Below that passengers can access a library area for computer use, a family and children’s area and a movie lounge on upper passenger deck. An eating area and forward lounge are located on the main deck. However, the design does not include hot food service.

“We can reduce operating costs by not having the full amenities you would have on a mainline,” Yost said.

DOT has a $117 million budget to build two ferries. The first would cost around $50 million to construct. Repeating the design for the second vessel could save up to 10 percent, Yost said. The total expected costs leave DOT with about a $10 million buffer.

Yost said DOT plans to issue a design concept report around April 1. Public comment received before March 8 can be included in this report. By the first of November the department wants to have a detailed design in hand, and wants to begin to lay the keel on Jan. 1, 2014.

Send comments or questions to Commissioner Reuben Yost at reuben.yost@alaska.gov.

The Alaska Marine Highway System also announced at the summit that it will run its fast ferries Chenega and Fairweather for the 2013 season. 

The high-performance vessels have experienced unexpected erosion and corrosion to the multiple engines. Recently AMHS inspected all 16 cylinders on each of the ships’ engines.

The state is still in a lawsuit with the engine manufacturers.

The M/V Chenega is running its route now and the M/V Fairweather is expected to return to service for its March 14 run to Sitka.

• Contact reporter Russell Stigall at 523-2276 or at russell.stigall@juneauempire.com.