(CNN) -- Civic-minded residents of Bismarck and Mandan, North Dakota, found there's nothing like a major flood to make new friends while filling thousands of sandbags. As cities along the Missouri River brace for the onslaught, the "Sunday Sandbag Thrown-Down" in Bismarck resulted in 1,600 people producing about 300,000 sandbags in six hours, Burleigh County Commissioner Mark Armstrong said. "The crisis is just beginning," Armstrong said Wednesday. "There has been a great community spirit." Over the past few weeks, Armstrong, who has filed several CNN IReport photos and videos of the river and flooding, has been sounding the alarm over the threat to the community.
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Residents fill about 300,000 sandbags in Bismarck area
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U.S. Army Corps of Engineers says it is committed to flood fight
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Melting snow pack adds to flooding woes on Missouri River
The Missouri River was 1.39 feet above flood stage Wednesday afternoon at @placeholder, with an increase expected later in the week.