Jimenez B, Chávez A
Treatment and Reuse Group, Institute of Engineering, UNAM Apdo Postal 70-472, Coyoacan 04510 Mexico, DF, Mexico.
Water Sci Technol. 2004;50(2):269-76.
Mexico City, with a population of 18 million, has been sending its wastewater for more than 100 years to the Tula Valley where it is used to irrigate 90,000 ha. Due to the large wastewater volume (60 m3/s) sent through unlined channels, combined with the use of very high irrigation rates, artificial recharge of the local aquifer has been occurring. This recharge is estimated in more than 25 m3/s. As a consequence, the water table has raised and several springs have appeared in the last decades with flows between 100 to 600 L/s. These springs and several wells are the water sources in the region. An evaluation of the Tula Valley aquifer quality was performed to analyze the use of such water as source of drinking water for Mexico City. The work is divided into 5 individual projects: (a) drinking water quality in the Tula Valley; (b) water availability in the Tula Valley; (c) wastewater treatment due to its use for irrigation, (d) use of membrane processes to treat groundwater; and (d) biota developed in the new surface water reservoirs. Results show that it is feasible to use this reclaimed water as drinking source.
拥有1800万人口的墨西哥城，100多年来一直将其废水排放到图拉山谷，用于灌溉9万公顷土地。由于通过无衬砌渠道排放的废水量很大（60立方米/秒），再加上灌溉率极高，当地含水层一直在进行人工回灌。据估计，这种回灌量超过25立方米/秒。因此，地下水位上升，在过去几十年里出现了几处泉水，流量在100至600升/秒之间。这些泉水和几口井是该地区的水源。对图拉山谷含水层水质进行了评估，以分析将这种水用作墨西哥城饮用水源的可行性。这项工作分为5个独立项目：（a）图拉山谷的饮用水水质；（b）图拉山谷的水资源可用性；（c）因用于灌溉而进行的废水处理；（d）使用膜工艺处理地下水；以及（d）新地表水水库中形成的生物群落。结果表明，将这种再生水用作饮用水源是可行的。
