Municipal Wastewater from Tertiary Treatment to Restore a Wetland Ecosystem in a Semiarid Environment

Perfecto Barragan-Pena*, Gabri


It has been well-reported the importance of wetland ecosystems due to the multiple services they provide to all organisms: besides they comprise habitats to a number of species, they contribute to recharge aquifers, and to carbon sequestration eventually. Municipal wastewater from a tertiary treatment was used to restore a wetland ecosystem. The site is located 23.5 Km south to Nogales, Mexico at Alisos watershed. The water was characterized for total coliforms and aerobic mesophiles, as well as Biochemical Oxygen Demand, to state its microbiologic quality. Soil characterization and hydrologic pattern study were carried out in order to know infiltration rate, type of soil, and watershed capacity. The design of the system consisted of three winding channels with gradual depth in the range 0.3-1.5 m that extended for 68 m downstream, at the end of which the channels enter a 0.8 m pond of 22 m of diameter. The forestation included native flora such as Juglans major, Asclepias angustifolia, and Platanus wrightii, among others. Due to its high microorganism content the water was conducted to a filtration process in conic tanks of 110 gal of capacity in which natural zeolite and limestone were packed. After 10 months of initiated both stabilization of system and earthworks to better maintain the green infrastructure on site, the area presents significant flora growth and a variety of pollinators can tell of the potential the restoration work has at Alisos watershed.

Relevant Publications in Journal of Research in Environmental Science and Toxicology