Algae blooms showing up in Lake Pontchartrain

North Shore Algae

NEW ORLEANS, La. (WVUE) - As the Bonnet Carre Spillway closes, one of the consequences of so much river water pouring into the lake started showing up this weekend. Boaters spotted patches blue-green algae blooms near the north shore of Lake Pontchartrain.

Fox 8 checks in with a water quality specialist to find out if we could see a repeat of last summer's widespread toxic algae.

The current opening of the spillway continues a string of unprecedented operation at the structure, pouring highly fertilized Mississippi River water into Lake Pontchartrain for the fourth time in three years.

Dr. Brady Skaggs is the water quality programming director for the Lake Pontchartrain Basin Foundation. He said, “It's a strange new normal to use the term. Certainly, this is a much smaller event.”

The foundation studies the health of Lake Pontchartrain.

“Right now the tools we have available to us don’t indicate that there is any strong or severe algal bloom like we saw in 2019, but we certainly are watching for it," Skaggs said.

The two long term openings last year fueled toxic blooms that closed beaches and recreational areas.

In August 2019, Mike Benjamin took Fox 8 on a tour of the green covered water in his boat.

“It’s pretty thick out here, man. I didn’t realize it was actually that thick in the water column. There’s a lot of solids that are suspended at the top and they go down maybe a foot-and-a-half, two feet. So, it’s definitely something to make you worry about. I wouldn’t swim in it," Benjamin said.

The low oxygen levels dying algae can cause also pushed sea life away from typical fishing grounds.

After so much disruption last summer boaters were concerned when they started seeing patches of the neon flora floating along the surface of the lake this weekend.

“Right now if there is a silver lining to much at all it’s a great conversation to have about data and the measurement of that data," Skaggs said.

He said the algae is always present, but there’s a lot we don’t know about what causes it to bloom or produce toxins. Scientist are using a new tool with satellite imagery to study water quality. “We’re still learning about the usefulness of that tool and the benefits and limitations as well,” Skaggs said.

The satellite information only outlines the amount of algae in a given amount of water. It can't show if it's producing toxins.

“There are a lot of questions that we still have to get a better understanding on as far as what turns those blooms on and how can we better model that information we get where there is a condition that may be hazardous to folks recreating in that water body," Skaggs said

He said samples from 2019 helped create a new comparison tool to determine when the lake is safe for swimming. Skaggs adds the more data and knowledge scientists can gather from each event helps us better cope with the next one.