In Mexico, 142 sites covering almost nine million hectares are listed as Ramsar wetlands. Given the complaints of local inhabitants regarding water quality, and the interest of the federal government for setting up a plan for wetlands protection, we evaluated the ecological condition of a wetland in rural Oaxaca, Mexico. Existing water quality data were compiled and analyzed. Among the parameters of interest were temperature, pH, DO, N, P, and fecal contamination. Even though microbial contamination was a primary concern, a more important worry to local users was the presence of pesticides in water due to inadequate disposal of empty containers and runoff from upstream farmlands. Public meetings with water users, researchers, and local and federal personnel were held to get the opinion about strategies for protection of the wetlands. Outcomes of the decision meetings using a decision-support system highlighted that to preserve the wetlands, the implementation of riparian vegetation (buffer zone) and the management of surface water should be considered as conservation practices. Law enforcement would improve the watershed and wetlands' health for preventing further deterioration. Because of the success in getting public participation and input, the approach will likely be replicated in other parts of the country.