From new ferries to a terminal overhaul in Woods Hole, the Steamship Authority will be embarking on some major capital planning and spending projects in the coming years.

At the monthly boat line meeting in Hyannis this week, the SSA governors took a look at planning for two major projects: the replacement of aging vessels and reconstruction of the terminal at Woods Hole.

Steamship Authority general manager Wayne Lamson told the Gazette Wednesday that the boat line is looking at a replacement study of the nine vessels in the fleet. Vessels have a useful life of 40 to 50 years, he said, and the SSA is sketching a plan to replace a vessel every five years or so.

First up would be the freight ferry Governor, he said, which was built in the mid-1950s. The Nantucket, built in 1974, would be up next, followed by the freight boats Katama and Gay Head, which were built in the 1980s.

More than a year ago, the SSA first discussed replacing the Governor, a freight ferry that is the longest and widest in the fleet.

To replace the vessels — beginning with the Governor — over the next 10 to 20 years, the SSA is looking at four options. The first would be purchasing and modifying an offshore supply vessel. While the low cost would be a bonus, Mr. Lamson said, the vessel would still be older.

Other options include paying more money for new vessels. A new freight vessel, perhaps larger than the Gay Head or the Katama, could be constructed, he said. The new vehicle could have the capacity to carry more freight at the expense of passenger space, or have more passengers but lose space for large trucks.

Other options could replace the Governor and other ferries with new passenger vessels of varying sizes. A new vessel like the Martha’s Vineyard could carry 800 passengers, and an Island Home-class vessel could carry 1,200 passengers.

Regardless of the vessel, Mr. Lamson said, the Governor’s replacement will improve service. The Governor runs only in the summer and during fair weather, and cannot be used on the Nantucket route. “Replacing the Governor with a large freight boat that could operate any time of the year and to either port would give us more flexibility,” he said.

The benefit of a larger vessel is that it adds extra capacity without adding a whole new vessel, he said, which spares the expense of another boat, crew and fuel.

But future decisions also come into play when looking at how to address the Governor. Borrowing costs are low right now, Mr. Lamson said, and if the boat line is going to build two vessels over the next 10 years, now is a good time to borrow money for the more expensive, larger vessel. The Governor could be replaced with a larger vessel, he said, and the Nantucket later replaced with a freight boat.

Once a decision is made about what type of vessel will replace the Governor, he said, decisions about things like design, power and length will be made. Financial information will be completed, and a deployment schedule created.

The authority has a debt limit of $75 million, Mr. Lamson said, with $50 million outstanding. They are paying off the principal at “a pretty good clip of $5 million year,” he said, so there is money available.

Studies will look at whether there will be any additional revenue from the changes — for example, if boats can take cars and trucks more quickly in the morning, space will be freed up for cars. While the SSA will never reach the point where they can take everybody when they want to go, he said, they have to match the level of service with demand so money isn’t wasted providing more service that actually needed.

The boat line is also looking at another big project: Woods Hole terminal reconstruction, which will be phased in over several years while the terminal continues to operate.

A feasibility study is under way by Bertaux + Iwerks Architects and is expected to take nine to 12 months. The study will determine the space needs of the authority, Mr. Lamson said, and three design alternatives will be narrowed to one.

Mr. Lamson said the SSA is looking at how to design the reconstructed terminal. Administrative offices may be relocated, he said, and a new terminal building constructed.

The SSA wants to continue to provide access for shuttles, buses, taxis and standby lines, he said. An added complication is that the terminal is in a flood plain. Mr. Lamson said the area will still be subject to flooding but the building will be elevated by one or two feet, and mechanical equipment would be located on the second floor so it would not be affected by floods.

Ferry slips will eventually be rebuilt and replaced because they are due for those improvements, he said, and there will be longer transfer bridges. The slips may be realigned as well, he said. There are now three slips in Woods Hole, though one is for standby and emergencies, he said, and the location of the north side slip makes it hard to unload. If the building is taken out and relocated, the third slip might be relocated to where the current building is. “That’s all up for discussion,” Mr. Lamson said.

In other business Tuesday, Mr. Lamson reported that the Steamship Authority’s new website, slated to roll out this spring, has been delayed and will not launch until next fall at the earliest. Oak Bluffs dock repairs are complete, according to a meeting summary, except for the installation of some sections of railing and a light pole that has been specially ordered from Germany.