Lake Pontchartrain Water Quality Monitoring March – May 2008 Bonnet Carre Spillway Opening Andrea Bourgeois-Calvin Program Coordinator Bonnet Carre Workshop June 13, 2008

LPBF Basin-wide Water Quality Monitoring Program Began January 2001 Three Objectives  Distribute water quality information to the public  Identify pollution sources  Provide data to research community and government agencies at all levels

Monitoring Sites and Parameters  Monitor recreation sites around Lake Pontchartrain Basin for * Water Temperature * Dissolved Oxygen * Specific Conductance * Salinity * pH * Turbidity * Fecal Coliform * Enterococci Data released to media

Spillway Time-Line Spillway opened on April 11, 2008 Spillway closed April 30 – May 8, 2008 Algae blooms first sited- mid-May in Lake Maurepas, Pass Manchac, and off Tchefuncte River. Tchefuncte River, May 26, 2008Lewisberg, May 19, 2008

Data: Southshore Sites, March – May 2008

Plume corresponds to data

Data: Northshore Sites, March – May 2008

Algae bloom corresponds to data

Conclusions Salinity Immediate and sustained drop in salinity on southshore Later drop in salinity on northshore Fecal Coliform Fecal coliform levels remained consistent on both shores Turbidity Turbidity spiked on southshore with opening of spillway Turbidity spiked on northshore with winds blowing from south and beginning of algae blooms in mid-May Dissolved Oxygen Dissolved oxygen levels consistently high on southshore Dissolved oxygen levels decreasing on northshore with growth of algae blooms (since mid-May and continuing to current)