Massive flooding in US in 1936

Titles: "Extra, Flood Warning" superimposed on high water / sign: "Flood Warning, a flood is coming. Suggest you move to high ground, Prepare now" / VS Sacramento River flows under bridge and streams past trees / VS river full of choppy ice; bridge surrounded by ice; man plunges detonator handle with resulting explosion under bridge / VS ice in river / Animation: map showing major affected rivers and streams in US superimposed on rushing river / VS 'rapids' / couple on roof of car in torrent (they will later die in the flood) / waters speed past vertical riverbank / VS men sandbagging (striped pants of inmate assisting) / VS waterfall and rapids / trestle of bridge passes on water / Note: exact day not known