I researched Olla and Chinampa. I was amazed by the high-efficiency of ancient low-tech irrigation systems. Although they have different scale, they have the same purpose of increasing water content, reducing evaporation, and increasing soil fertility. Maqsam is also a low-tech water dividing device for water justice. I am interested in whether Maqsam can restore habitat and divert water to communities for irrigation and storm water recovery, in order to restore the ecology of city watershed.