(S (S (BASENP (NN Report) (NNS authors)) (VP (VBP claim) (SBAR (IN that) (S (NP (BASENP (DT the) (NN price)) (PP (IN of) (BASENP (NN water)))) (VP (MD could) (VP (VP (VB double) (CC or) (VB triple)) (PP (IN over) (BASENP (DT the) (JJ next) (NN two) (NNS decades))))))))) (PERIOD .))