If you've taken a walk along the Lake Pontchartrain lakefront this week, you may have noticed something unusual. Water levels are significantly lower than they were just days ago, exposing portions of the shoreline and seawall that are typically underwater.
While the dramatic change has prompted questions from residents, Pontchartrain Conservancy Executive Director Kristi Trail says the explanation is a natural one.
"While we do call it Lake Pontchartrain, it is an estuary," Trail said. "An estuary means that this body of water is tidally connected out to the Gulf."
Unlike inland lakes, Lake Pontchartrain's water levels are largely driven by wind. Just last week, Tropical Storm Bertha pushed water into the estuary, causing levels to rise several feet. After the storm passed, shifting northwest winds began pushing that water back toward the Gulf through the Rigolets and Chef Menteur Pass.
"About a week ago, with Tropical Storm Bertha, the lake levels were up almost to three feet," Trail said. "Then on Monday, we had a big shift in the winds, and the wind started coming out of the northwest. Now it's pushing that water back out of the lake, and today the lake is extremely low."
One of the easiest places to see the difference is at the Pontchartrain Conservancy's New Canal Lighthouse.
"One of the things we look at there at the lighthouse is the seawall and how many steps we can see," Trail said. "You can see just about every single step on that seawall as of now."
While rainfall can have some influence, particularly after heavy rains north of the lake feed area rivers, the day-to-day fluctuations most people notice are typically caused by changing wind patterns rather than precipitation.
The changing water levels also affect the lake's salinity, or salt content, but Trail says that's nothing new for the wildlife that calls the estuary home.
"The marine life that resides in Lake Pontchartrain is pretty used to it," she said. "If there is an instance where they're not too happy, they'll swim out to the Gulf and come on back later."
For those planning to fish, boat or spend time along the lakefront, Trail says the lower water levels shouldn't keep anyone away. Boaters should simply use extra caution in areas that may be shallower than usual.
She also encourages residents to check current lake conditions before heading out.
"We test the water quality of the lake every single week," Trail said. "Those results are posted on our website every week. We also have a water level gauge at our lighthouse, and those lake levels are posted in real time."
Looking ahead, Trail says the changing lake levels are also a reminder of southeast Louisiana's unique geography and the importance of preparing for hurricane season.
"We're here in a coastal city, and we're very affected by tides and storm surge," she said. "That's why it's so important that we protect the lake and the wetlands ahead of it to buffer that storm surge."
While the lake may look dramatically different today than it did just a few days ago, experts say that's simply the nature of one of Louisiana's most dynamic bodies of water.
