Despite a state report to the contrary, Sebastopol officials said the Laguna de Santa Rosa wetlands is plagued by excessive amounts of two nutrients and pointed to an infestation of the water weed Ludwigia as proof.
Mayor Larry Robinson, in a letter today to the State Water Resources Control Board, said nitrogen and phosphorus from residential and agricultural runoff are contributing to a serious public health problem that threatens the laguna's future.
Robinson criticized an agency report that said the nutrients are no longer at dangerous levels and recommends they be removed from a federal list of substances polluting the laguna.
Such a "delisting," officials said, could jeopardize hundreds of thousands of dollars for laguna protection and restoration.
"Why they are trying to take this action is beyond me," Robinson said. "There's a serious load of nitrogen and phosphorus in there."
Craig J. Wilson, the agency's chief of water quality assessment, declined to comment.
He referred calls to water board spokesman Chris Davis, who said numerous tests showed nitrogen and phosphorus levels did not exceed public health protection levels.
The federal Environmental Protection Agency put the nutrients on the list of laguna pollutants in 2002, but "our analysis couldn't support their findings," Davis said.
The real culprit is dissolved oxygen, a pollutant that is linked to the presence of nitrogen and phosphorus, Davis said.
He said removing dissolved oxygen will reduce levels of nitrogen and phosphorus.