All savings on deck

JUST WHEN state transit officials and boat operators should be talking about expanding water transportation for the summer, the cash-strapped MBTA is proposing to eliminate its Boston Harbor ferry service. The T is struggling with a $161 million deficit. But there are better ways to address it than scuttling commuter ferries.

Start with fuel. Two private boat operators under contract with the T provide ferry service between downtown and the South Shore, in addition to an inner harbor run between the Charlestown Navy Yard and Long Wharf. Combined, they burn about 1.3 million gallons of diesel fuel annually at a current cost of about $3.30 per gallon. But the T pays just $3.16 per gallon for the same fuel. By providing ferry operators with fuel at the bulk purchase rate, the T could shave almost $200,000 off the $3.6 million subsidy that it now provides to the ferry operators.

These and other cost-cutting ideas, such as electronic ticketing systems, have surfaced for a few years now, according to Bruce Berman of the nonprofit Save the Harbor/Save the Bay. But something always seems to get in the way. This time, T officials worry that “volume differences’’ will prevent them from negotiating the same prices that they currently pay for fuel for the commuter rail.

But why not try?

Ferry commuters in Hingham, Hull, and other South Shore communities appear willing to absorb both fare increases and cuts in service as long as they still have an alternative to the congested roadways. And they note that they already pay a greater portion of the cost of their trip (58.5 percent) than riders on other parts of the T.

The fate of the commuter ferries is also linked to future recreational and tourism opportunities on the harbor. Harbor activists like Berman are urging ferry operators to find ancillary uses for their vessels during non-commuting hours, such as water loops between cultural institutions or increased trips to the Boston Harbor Island national park. But those ideas could dry up without the commuter ferry service as a base of operations.