Associated PressDENVER — A dry March has taken a toll on Colorado's snowpack, raising concerns about low streams during the summer and a potential strain on the water supply. The Denver Post reports (http://goo.gl/9BafLM ) the dry spell melted the statewide snowpack from 87 percent of average at the end of February to 69 percent as of Thursday. The Natural Resources Conservation Service says snowpack in southwestern Colorado basins has dropped to 55 and 58 percent of average.