(6:30 a.m. EDT) -- At least 20 river cruises have been affected in Germany on the Danube and Elbe rivers after lower than normal water levels have forced some cruise lines to undertake complex logistical maneuvers to keep tours running.
Below is a summary of itinerary alterations. Cruise Critic will continue to monitor water levels in the regions and update you with further reports.
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Viking Cruises has seen more than a dozen of its itineraries affected, and maintains an updated list on its website. In addition to "ship swaps" -- where the line undertakes a passenger exchange (usually via bus) between two ships positioned on either side of an impassable stretch of river -- at least one cruise has been more severely affected.
Departure for the June 24 Budapest to Amsterdam northbound sailing on the Viking Atla longship was delayed by two days, according to the website.
"This itinerary will begin with a two-night hotel stay at the Boscolo Budapest Hotel, as Viking Atla's sailing schedule has been altered by the river conditions and the ship will not be able to reach Budapest in time for embarkation," the statement read.
For the June 24 sailing on Atla, Viking deployed representatives to meet passengers at the airport on arrival and stationed an agent at the original embarkation point near the Chain Bridge in Budapest. A Viking spokesman also told Cruise Critic that customer relations teams are communicating directly with all affected passengers about "the options that best suit the individuals, including continuing with the modified itinerary."
Thus far, the line has undertaken ship swaps on 10 other cruises with departure dates through July 1.
The line advises other passengers scheduled to sail the Danube River between Regensburg and Passau in the coming week to assume that their cruise is still scheduled for regular departure.
"Should conditions change and additional alterations become necessary, we will continue to inform impacted guests as soon as we are aware of any itinerary fluctuations. If you have any questions, please call Customer Relations at (00) 1-877-668-4546, extension 4525, Monday through Friday, 7:30 a.m. to 5:00 p.m., PDT."
Scenic Tours has also undertaken "ship swaps" on some of its Danube itineraries.
The line posted an updated cruise schedule on its Facebook page (June 26) covering seven departures between June 30 and July 30.
Scenic's statement said: "Due to the recent low water levels experienced on parts of the Danube River, there has been minor impact to our sailing schedule.
Gems of the Danube River Cruise departing Budapest on 30 June (PNB300614.2) will now be embarking onto the Scenic Ruby.
Jewels of Europe River Cruise departing Amsterdam on 2 July (STC020714.1) will now be embarking onto the Scenic Diamond.
Gems of the Danube River Cruise departing Nuremberg on 7 July (PNB040714.1) will now be embarking onto the Scenic Ruby.
Jewels of Europe River Cruise departing Budapest on 14 July (STC140714.2) will now be embarking onto the Scenic Ruby.
Jewels of Europe River Cruise departing Budapest on 16 July (STC160714.2) will now be embarking onto the Scenic Diamond.
Romantic Rhine and Moselle River Cruise departing Amsterdam on 28 July (AMBA280714.1) will now be embarking onto the Scenic Ruby.
Jewels of Europe River Cruise departing Amsterdam on 30 July (STC300714.1) will now be embarking onto the Scenic Diamond.
All other details with regards to embarkation and the cruise itinerary remain unchanged."
APT, too, has done a number of "ship swaps. The line posted updated schedules on its website (June 30).
APT's statement said no shore excursions have been affected. Passengers with questions are advised to contact APT. In Australia, the number is 1800 792 775 or from overseas +613 8526 2411 (lines are open 9 a.m. - 5 p.m. AEST), or passengers can email TravelUpdates@aptouring.com.au.
Affected river cruises are:
Magnificent Europe (EUMC15) aboard the MS AmaVerde. Departed Amsterdam, Saturday 21 June 2014. Guests on the MS AmaVerde swapped onto the MS AmaBella on Sunday 22 June 2014. There has been no impact to touring inclusions or itinerary.
Magnificent Europe (EUMCR15) aboard the MS AmaBella. Departed Budapest, Saturday 21 June 2014. Guests on the MS AmaBella swapped onto the MS AmaVerde on Sunday 22 June 2014. There has been no impact to touring inclusions.
Magnificent Europe (EUMCR15) aboard the MS AmaVerde. Departs Budapest, Saturday 5 July 2014. Guests on this tour will board the MS AmaBella in Budapest. Halfway through the cruise they will swap onto the MS AmaVerde. There will be no impact to touring inclusions or itinerary.
Magnificent Europe (EUMC15) aboard the MS AmaBella. Departs Amsterdam, Saturday 5 July 2014. Guests on this tour will board the MS AmaVerde in Amsterdam. Halfway through the cruise they will swap onto the MS Amabella. There will be no impact to touring inclusions or itinerary.
For all other guests sailing with us, we can confirm that our river cruises are operating as scheduled. This includes the following departures:
Magnificent Europe (EUMCR15) aboard the MS AmaDante. Departed Budapest, Sunday 22 June 2014. The MS AmaDante is unaffected by the low water disruptions. We shall continue to monitor this situation.
Magnificent Europe (EUMC15) aboard the MS AmaReina. Departed Amsterdam, Sunday 22 June 2014. The MS AmaReina is unaffected by the low water disruptions. We shall continue to monitor this situation.
European Gems (EUTC15) aboard the Travelmarvel Jewel. Departed Amsterdam, Monday 23 June 2014. The Travelmarvel Jewel is unaffected by the low water disruptions. We shall continue to monitor this situation.
European Gems (EUTC15) aboard the Travelmarvel Diamond. Departed Amsterdam, Monday 30 June 2014. The Travelmarvel Diamond is unaffected by the low water disruptions. We shall continue to monitor this situation.
Cruises on two of Avalon Waterways ships have been impacted by the low water.
A statement on Avalon's Facebook page said: As we have previously reported, due to the lack of rain in Europe, water levels between Regensburg and Passau are low. To date, these water levels have affected three sailing days for both the Impression and Illumination this week. Both ships were sailing upstream and, unfortunately, it's more difficult to traverse low waters going upstream than downstream."
"While both ships have remained docked in Passau, we have provided passengers sightseeing choices. For instance, on Tuesday, one group opted for leisure time in Passau, while another group chose sightseeing in Prague. The hope and goal for all passengers is to help them make the most of their journey and enjoy all that Europe has to offer."
Uniworld Boutique River Cruise Collection
An update about the low water situation on Uniworld's Facebook page says that its River Ambassador and River Duchess ships have incurred "minor delays," but are back on schedule and have not missed any scheduled excursions.
For two of its other affected ships, the statement says it will undertake a "ship swap," moving passengers from River Empress to River Princess (June 27).
And finally, the line says there will be another "ship swap" on the upcoming July 2 River Empress and July 5 River Princess sailings, which will ultimately get passengers on those sailings on the ship they were originally meant to sail on.
The line said: "We expect the cruises to be able to complete their respective programs in their entirety. We are now beginning the process of contacting everyone on those sailings to advise them of the change of ship."
A spokesman for Riviera Travel told Cruise Critic the line would be forced to cancel its June 27 Elbe River cruise onboard Swiss Ruby. The line is calling its customers to let them know about the decision.
Riviera also canceled an identical sailing last week and offered all affected customers a full refund or the opportunity to transfer onto another cruise in 2015.
--By Jamey Bergman, UK Production and River Section Editor