European River Cruises Hit a New Obstacle: Not Enough Water

“We still saw a lot and Avalon was good to us, but it just wasn’t the trip I spent nearly a year imagining,” Ms. Milosch said.

It’s not just passengers who have had to adjust to the drought and planning challenges.

Cruise companies including Riviera, which Ms. Needham’s family sailed with, and Avalon, which Ms. Milosch’s family used, have had to think of ways to keep trips intact, despite the low waters.

“We’ve had to find creative solutions,” said Rudi Schreiner, president and co-owner of AmaWaterways. “We don’t know a week ahead if the water will hit critical levels, but people book their trips sometimes a year ahead and we want to provide them with the best possible vacation.”

If the water is too low in certain areas, Mr. Schreiner’s company tries to make it up. For each day that the cruise deviates from the planned itinerary, passengers receive a 15 percent discount off a future trip. And if the trip cannot go forward on the river, bus tours are provided. Similar deals are provided by other companies.

“We still want you to have a good time, but maybe that’s in a slightly different area than planned,” Mr. Schreiner said.

Typically, if a cruise is canceled or moved to land, a full refund — including airfare, if booked as part of the package — is offered. Travelers who book their own airfare separately will not be guaranteed a refund for that part of their trip unless they bought travel insurance or a refundable ticket.