MILIEU was given the mandate by Parks Canada to design, construct, and install an eel ladder at the Saint-Ours Dam located on the Richelieu River. MILIEU monitored the passage of eels at the the eel ladder for three years. Furthermore, MILIEU worked at the new multi-species facility to optimize its operation.

MILIEU is presentely managing the project for the design, construction, and installation of a flow-through screen barrier on the Morpions Stream. Presently, the unimpeded Morpions Stream provides a large spawning and rearing habitat for Sea Lampreys, who have a sizable impact on the Lake Champlain ecosystem.

The survival of smolts going through the Mitis-1 Power Dam was assessed by MILIEU. The smolts were tagged, released into the turbine and collected downstream.

The Lake Sturgeon is a closely watched species because of its precarious status and its historical importance to the commercial fishing industry. MILIEU conducted a study to determine if the west of Lake St. Louis was used by sturgeon as a spawning ground.