NEW BUFFALO — Drivers aren't the only ones being hit hard by the holiday weekend "jump at the pump." Boats across the area are tied up in docks, as the cost to fill them up continues to rise.

Some boats get as little as half a mile to each gallon of gas, and that's left many boat owners with a tough choice this holiday weekend: pay up, or tie up.

AAA predicts 40 million Americans will travel away from home over the Independence Day weekend. That's down 1.3% from last year, and many experts say local gas prices hovering between $4.05 and $4.19 are to blame.

But at Oselka Marina in New Buffalo, marine diesel fuel was selling Friday at $4.90 a gallon. And at that price, even an average sized tank adds up quickly.

"It costs about $500 to fill up my boat," said Hank Nehrling, a boater from Indianapolis whose boat is docked in New Buffalo.

"Mine is $800 or $900," said Bob Wilder in the boat slip next door.

"It's about $1,200 to fill up my tank," said Hank Kubiak, a boat owner from South Bend. "That's about double from last year."

It also burns up quickly.

"We get one mile to the gallon," said Nehrling.

"When I purchased the boat it cost me $200 to fill it up," said Kirk Amptmeyer of Schererville. "Now, it costs me $800, and I can burn through one tank in a day just running it hard. It's ridiculous. It's beyond frustrating."

It's already been enough to change almost every boaters habits we spoke with at Oselka Marina.

"Most people are still boating, they just aren't taking any long trips," said Marina owner Jim Oselka.

"The days of driving [the boat] up to Saugatuck and South Haven are gone," said Wilder.

"That might cost me $1,000 round trip," added Kevin Murray, a boater who now lives in New Buffalo. "Last year it was $600. That's still expensive, but now, it's an easy pass on that."

Even the simple 9 mile trip to Michigan City, Indiana now costs upwards of $100 in fuel for the average boater.

It's one reason why Murray and others at the dock Thursday were coming up with different Independence Day plans this year.

"We're hanging out on dry land, enjoying the non-use of gas," he said.

"We don't call them cruisers anymore. We call them houseboats!" added Nehrling. "We're staying put."

But it's not just the docks seeing the impact of the jump at the pump.

Staple industries like convenience stores and restaurants have seen a slight drop in sales.

"But no big drop-off at all," said Stephen Sanaghan, Manager at Casey's Bar and Grille in New Buffalo. "People still have to eat, and the town is still full of people right now."

But at "tourist dependent" stores like New Buffalo's Clipper Ship Gallery, sales invoices prove that crowd isn't spending.

"We have seen a lot of people in the store, but they are spending 20-30 percent less per invoice than they were before," said owner Bev Sullivan. "And this weekend is critical to our bottom line."

But both Sullivan and Sanaghan are much more worried that a weakening economy and rising gas prices could eventually mean smaller crowds. If that happens, both say they could be in murkier financial waters.

But for now, both shops are keeping their fingers crossed along with boaters that prices at the pump go down. If they don't, some say they'll only have one option left.

"Use one tank of gas per year. And "that's what I'm going to do. I'm not going to go anywhere," said Amptmeyer.