Residents and tourists waded through knee-deep water today as they navigated the city’s narrow streets and alleys, and its historic St. Mark’s Square was inundated. Boxes of tourist merchandise floated inside the flooded shops around the square and even the city’s famed pigeons sought refuge on rooftops and windowsills.

One of the highest tides in its history brought Venice to a virtual halt, rekindling a debate over a plan to build moveable flood barriers in an effort to save the lagoon city from high tides.

City officials said the tide peaked at 61 inches, well past the 40-inch flood mark, as strong winds pushed the sea into the city.

Alarms went off at 6:37 a.m. to alert citizens, but many residents were taken by surprise because authorities had initially not forecast such a high water level.