The Wisconsin Natural Resources Board unanimously approved public hearings on a proposed rule that would create a process for setting site-specific phosphorus standards on the state's bodies of water. Wisconsin already has statewide water quality standards for phosphorus, but these vary depending on the water system. Phosphorus in the water can support the growth of algae and other plants, but too much can overwhelm the system. The proposed rule would pinpoint situations where site-specific standards may be appropriate, according to Marcia Willhite, water evaluation section chief with the state Department of Natural Resources.