In the territory of North Grande-Terre, two works require priority action: the treatment plant of Château Gaillard au Moule and that of Guery in Anse-Bertrand. The Château-Gaillard project presented here will aim to respond to a health emergency. To do this, the choice has been made to reproduce a model that has already fulfilled all its promises and proves itself: the Plant Plant Filter Purification Station installed at the Duval Petit-Canal site. It is important to note that this is the first ecological and innovative natural station that was carried out as part of the ATTENVIVE project (Sewage Sanitation adapted to the Tropical context by Extensive Treatment using plants) in Guadeloupe. This operation falls within the framework of the upgrading of infrastructure related to sanitation in order to ensure the preservation of the environment and natural environments, including water bodies. It is an operation that responds to the call for projects of the Office de l’Eau de Guadeloupe aimed at the compliance of all wastewater treatment plants malfunctioning in the territory. It will make it possible to bring about a rapid improvement in the quality of service rendered to the user. The aim is to preserve the living environment and promote a sustainable solution.