2011, the Fédération Internationale de Natation decided cancel its annual swim marathon in the canyon as they claimed that pollution levels in the river posed a risk to swimmers’ health. The Comisión Nacional del Agua and the government of Chiapas disputed this, presenting their own test results stating that levels were below such levels. There are year-round and seasonal efforts to clean the river within the canyon and the area just upstream from it. Much of the daily effort is undertaken by workers with the Comisión Nacional de Áreas Naturales Protegidas (CONANP) and the Secretariat of Tourism in Chiapas, which extract twelve tons of garbage from the Grijalva river each day. Most of the season cleanup coincides with the rainy season, especially in September and October, when rains are heaviest. This seasonal effort has included local police, civil protections agencies, social organization, the army and individual volunteers. Efforts can involve up to 600 people at a time using 32 boats from four of the tourist cooperatives. During the annual campaign to clean the canyon in 2005 more than 60,000 tons of trash was removed. Generally, about forty tons of garbage is collected each day during these campaigns. While the cleanup efforts have improved the situation in the canyon, the garbage reaccumulates especially during the rainy season. Part of the price that tourists pay for boat rides into the canyon pays for cleanup efforts, but the boat operators state that the canyon remains filled with trash. Conanp also states that cleanup efforts are insufficient. Mexico's federal environmental agency, the Secretaría de Medio Ambiente y Recursos Naturales (Semarnat) states that it cannot get involved in the situation as it is the municipalities that have the responsibility for disposing of trash appropriately. However, many of these local governments do not have landfills or the separation of recyclables. Tourism The scenery of the canyon has become a major tourist attraction for the state, with developments for eco tourism and extreme sports. The navigable part of the Grijalva River is mostly used to ferry visitors into the canyon area. The park has six lookout points accessible by land called La Ceiba, La Coyota, El Roblar, Tepehuaje, Los Chiapas and Manos. In the rainy season, tourism is enhanced by the activity of waterfalls such as the Árbol de Navidad, Cueva del Hombre, Cueva del Silencio, Cueva de Colón, Cueva de Colores and Cueva del Suspiro. A