Sometimes there's a limit even to what you can take for free. Portland has found it with the proposed free police boat offered through a grant from the U.S. Department of Homeland Security.

Police officials announced plans to buy a boat with federal help on Tuesday, but by Thursday said they were just studying the issue. By Monday, they should conclude the study and find that this would be the wrong purchase at the wrong time.

Yes, Portland is a port city, and yes, port security is a national priority, and yes, Portland police officers are sometimes called to places that are not accessible by dry land.

But, no. Portland should not take on the responsibility for another expensive piece of equipment that will require fuel, maintenance and special training for the officers who operate it. Not when the city is facing another difficult budget year with the likelihood of layoffs and cuts to services – including public safety services.

The cost associated with federal generosity should be obvious to anyone who paid attention to recent stories about the new $3.2 million fireboat. Its cost was shared between the city and the federal government, including $1 million from the Department of Homeland Security. But the boat is too small for the crew to sleep aboard, so the city recently considered spending $1.8 million to build quarters for them, without any federal help. That plan has wisely been shelved, but none of the available alternatives under consideration are free either.

Port security is the job of the Coast Guard, and the agency is much better equipped and trained to do it. While a local police presence could enhance that mission, a much better investment would be in buying another boat for the Coast Guard – if another boat is needed for Portland – and encouraging joint operations with the city's police department.

For purely local police matters, officers can continue to catch rides to the islands and boats in the harbor with the fire department. It may not be ideal, but many city departments will be operating in less than ideal circumstances this year.

So, they can study the issue all they want, but when it comes time to accept a "free" boat, Chief James Craig should just say, no thanks, we can't afford it.