DEQ monitors water quality in wake of recent flooding

Staff reports

The Louisiana Department of Environmental Quality, in collaboration with the U.S. Army Corps of Engineers and other state, federal and non-governmental partners, continues to assess and monitor water quality in the wake of the recent Mississippi River flood event that impacted Louisiana. In response to the opening of the Bonnet Carre’ Spillway and the Morganza Floodway, DEQ continues to take water quality samples along the Mississippi River, Atchafalaya River and Lake Pontchartrain Basin.

As a result of the cresting of the Mississippi River last spring, the Bonnet Carre’ Spillway was opened in May to relieve pressure on the New Orleans area levees. During that period, Mississippi River water flowed through the spillway, entered Lake Pontchartrain and made its way into Breton Sound, Chandeleur Sound and Mississippi Sound. The Morganza Floodway was also opened in May to relieve pressure on the Baton Rouge area levees. During that period, Mississippi River water flowed through the Morganza floodway and eventually into the Gulf of Mexico. Prior to the events, DEQ developed sampling plans that established water monitoring strategies for Lake Pontchartrain and Morganza floodway waters. The plans were implemented in order to identify and address any possible issues that may have an impact on water quality.

“Before, during and after the flooding event, DEQ scientists took water samples and handled them in accordance with established standard operating procedures associated with DEQ’s Ambient Water Quality Monitoring Network,” said DEQ Staff Scientist Jeff Dauzat. “When algal blooms are observed, additional sampling is conducted to determine if harmful algal species are present. Thus far, we have found that while indicators of algal populations show increases above non-diversion years, they are currently below other years when diversions occurred.  The DEQ will continue to monitor for the development of potentially harmful algal blooms.”