Based on a research developed in the USA [I] for the subsurface irrigation ofredwood forests(Sequoiadendrum Gigantea), this paper analyzes treated sanitary wastewater reuse as analternative for carbon sequestration and oxygen generation through root assimilation ofnutrients inside them, at rates that consider the transpiration, evapotranspiration andsubsurface infiltration processes in arboreal areas of urban lots. Through buried ecochambers,the tree roots make contact with treated sanitary wastewater (stored in tanks in case its flowexceeds the evapotranspiration capacity of the arboreal area), and pumped according to itsseasonal transpiration rate. This arboreal area will act as a nutrient pump to evapotranspiratepurified water and oxygen while sequestrating carbon dioxide from its roots, withoutcollecting, pumping, treatment and disposal of sanitary wastewater by the public systems,acting as a "Smart Drainage System" which comprises a local sanitary wastewater treatment,as well as the selective rainwater reservation at the urban lot, for multi-useful profits, such as:garden irrigation, sanitary installations, floor and pavement washing, among others.