Prospects for a new ferry service starting next summer between Portland and Nova Scotia got a lot better this week.

Officials on both sides of the Gulf of Maine say three qualified companies submitted proposals to the Canadian province Thursday to operate a ferry service between Yarmouth, Nova Scotia, and New England.

Portland was not named in the request for proposals, and details of the proposals have not been made public. But Greg Mitchell, Portland’s economic development director, said he was assured Friday by Nova Scotia officials that Portland would be the port of call in the United States under all three proposals.

“We are staying in close contact with them and stand ready to work with them every step of the way to re-establish the service,” Mitchell said. “Our port facilities are in excellent condition, and we can be ready to start service in short order.”

A lot of tourism dollars are at stake. At its peak, in 2002, the Scotia Prince ferry carried 322,000 round-trip passengers between Portland and Yarmouth, and many of those passengers ate meals and stayed overnight in Greater Portland.

Ferry service is even more important for southwestern Nova Scotia, a relatively isolated area where tourism has declined significantly since ferry service stopped.

This is the fourth summer without ferry service between Yarmouth and Portland, since Bay Ferries Ltd. canceled its high-speed service on The Cat after the 2009 season, citing growing fuel costs, declining passenger counts and the loss of a subsidy from Nova Scotia.

Nova Scotia is now offering $21 million over seven years to subsidize startup costs for a new service. Rather than a high-speed ferry, the Canadians are looking for a slower, cruise-type ferry like the Scotia Prince, which ran between Yarmouth and Portland from 1982 to 2004.

The Nova Scotia government said Friday that it has received proposals from P&O Ferries, Balearia Caribbean Ltd. and STM/Quest.

The government is pleased that three “experienced” operators have shown interest in the route, said Graham Steele, Nova Scotia’s minister of economic and rural development and tourism.

P&O Ferries, based in Dover, England, owns 20 ferries that operate between England, Holland, France, Belgium and Ireland. It employs 4,000 people and has gross annual revenue of more than $1.5 billion.

Balearia Caribbean Ltd. operates a daily ferry service between Fort Lauderdale, Fla., and Freeport, Bahamas. The company is owned by Bale?a, a Spanish shipping company that operates ferries in the Mediterranean.

The proposal by STM/Quest is a joint venture by Quest Navigation Inc., based in Eliot; International Shipping Partners, a passenger ship management company based in Miami; and ST Marine, a shipbuilding company in Singapore.

The proposal calls for ferry service between Yarmouth and Portland on a vessel built in Singapore that has 162 cabins, two restaurants and capacity for 1,215 passengers.

At 531 feet, it is longer than the Scotia Prince. It was designed to cross the English Channel between Le Havre, France, and Portsmouth, England. The company that planned to buy it canceled the purchase before delivery, citing construction delays.

The ship would be named the Nova Star.

Steele said the next step is to evaluate the proposals to determine whether the companies offer viable and sustainable service.

The provincial government has not set a deadline for a decision. Its criteria will include each company’s financial stability, management structure, experience in the tourism industry and management history.

Keith Condon of Yarmouth, co-chair of the Nova Scotia International Ferry Partnership, said he is thrilled by the response to the government’s request for proposals, the second request in the past year. The first failed to lure experienced companies.

“This is better than good. It’s an excellent response,” Condon said Friday.

Condon will serve on the panel that will evaluate the proposals. He said the panel will dedicate the month of July to the effort. The province wants service by next summer.

In April, Condon and a Nova Scotia tourism official pitched the ferry service to operators at the world’s largest international ferry conference, held in Rotterdam, Netherlands.

While he never said in his presentation that Portland would be the port of call in the United States, Condon used statistics about the Scotia Prince service and Portland, such as the number of people who live within a day’s drive of the city.

While many more people live in Boston, he said, Portland is a better choice for a port of call because it’s closer to Nova Scotia.

The Scotia Prince took 11 hours to sail between Portland and Yarmouth, so it could make the round trip every day. Boston is too far away to support daily service to Nova Scotia, Condon said.

Portland has the infrastructure to support ferry service — the Ocean Gateway terminal, built by the city and the state in 2008 for $20.5 million.

The terminal was designed to be a waiting area and customs screening site for passengers getting on and off the Scotia Prince, but the ferry never used it because the service had been canceled by the time Ocean Gateway opened.

The Cat, the high-speed ferry that Bay Ferries Ltd. operated, used Ocean Gateway for two summers.

Neil LeBlanc, co-chair of the Nova Scotia International Ferry Partnership, said he hasn’t read the three proposals but the companies that expressed interest all discussed Portland.

Portland, he said, has “a lot of advantages that will be reflected in the proposals.”

Officials with Balearia Caribbean Ltd. did not return phone calls.

Quest Navigation and ST Marine said in a written statement that their partnership offers the “financial strength and operational expertise” needed to launch a new cruise ferry service between Portland and Yarmouth.

Brain Rees, spokesman for P&O Ferries, would not say which American port it would use for the service because the company does not want to disclose details about its proposal.

However, he said the company would operate a year-round service in which tourists would make up most of the business during the summer and trucks would support the business in the winter.

He said the vast majority of the company’s ferries in Europe offer year-round service and cater to both travelers and commercial shippers.

“We understand big, multi-purpose ferries that mix tourism and freight,” he said. “You’ve got to balance your business instead of putting all your eggs in one basket.”

Tom Bell can be contacted at 791-6369 or at:

tbell@pressherald.com

Twitter: TomBellPortland