ST. LOUIS (AP) – Mayors from Mississippi River communities are joining with members of Congress to draw attention to the waterway and the needs of communities dotting its banks.  About a dozen mayors from communities big and small were in Washington on Thursday to announce formation of the Mississippi River Platform. The goal is to raise awareness of issues such as water quality, community development and drought and flood preparation.  The mayors, members of the Mississippi River Cities & Towns Initiative, will work with the newly-formed Mississippi River Caucus. That’s a bi-partisan group of members of Congress.        The river attracted a lot of attention over the winter when drought caused it to dip near record low levels between St. Louis and Cairo, Ill. Barges were forced to reduce loads and traffic was nearly halted.