Ryan, 7-years-old and her brother James McConnon, of Old Town Alexandria, enjoy the standing water at the corner of King and Union Streets on Tuesday, October 30th, 2012. The morning high tide was not as deep as expected but still drew quite a crowd. (Tracy A. Woodward/The Washington Post)

The Potomac River, swollen by runoff from Hurricane Sandy, climbed out of its banks in Old Town Alexandria at high tide Tuesday night and flowed up King Street, past the doors of stores and restaurants.

The water appeared to reach points about 200 yards from the river at times, and forecasts indicated that the flooding could be repeated or exceeded at high tide on Wednesday morning.

That section of Alexandria, where streets slope down to river level, is one of the area’s best known attractions for tourists, and is one of its most flood-prone spots. It is particularly vulnerable to high river flows, caused by runoff from storms or melting snow in the upper reaches of the river basin.

Flood stage at Alexandria is 2.7 feet, according to the National Weather Service. Before the runoff began to subside late Tuesday night, the river surpassed the four-foot threshold for moderate flooding.

Georgetown also experienced some flooding in low-lying areas. The highest water level Tuesday night on the Potomac in Georgetown was about 7.6 feet. The river is expected to rise another foot onWednesday, taking it above the seven-foot, moderate flooding threshold, but keeping it below the 10-foot standard for major flooding there.

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