As the Rio Grande dries out months early, water managers look to blessings, prayers and groundwater to save the acequias that have spread water, history and culture to farmers and families since the 16th century.By Tina DeinesALBUQUERQUE, N.M.—On a sunny spring morning at the end of March, a woman raised her little girl above an irrigation ditch that runs just west of the Rio Grande in Albuquerque’s South Valley. The toddler, with a braided head piece crowning her long, brown hair and artificial flowers around her neck, enthusiastically tossed an assortment of colored petals into the water below as a small crowd cheered.