• moitoi@feddit.de
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    9 months ago

    Spanish drained the lake in multiple steps to build the modern city. The water they are using is ground water, pumped in an aquifer. Mexico city has a network of canals to drain the storm water.

    The other issue is the aquifer doesn’t recharge enough due to the urbanization and consumption. One solution is to use the rain water by cleaning it and storing.

    • merc@sh.itjust.works
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      9 months ago

      They drained the lake, but if I understand how lakes work, the aquifer is connected to the lake bed. So, initially there was so much water in the aquifer that some of that water was above ground in the form of a lake.

      One solution is to use the rain water by cleaning it and storing.

      Are you saying that right now the rain water doesn’t reach the aquifer? Like, it’s drained outside the city? Or that instead of having it trickle down into the aquifer, they could collect it above ground and make it available more quickly by cleaning and storing it in man-made structures?

      If it’s the second, it sounds like not allowing the rain water to reach the aquifer will mean that it drains more quickly.

      • moitoi@feddit.de
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        9 months ago

        You don’t have all the time an aquifer under a lake. You can find lake on impermeable soil, for example. If connected to an aquifer, you still have some sort of soil between the lake and the aquifer. They drained the water of the lake and the soil when solid at the air. This is why if the aquifer is too low, you have a risk of collapsing.

        With urbanization, they build houses, buildings, later parking, paved streets, etc. Each of them is sealing the ground. The water flow in the storm water canals out of the city instead of going in the aquifer. You have a similar issue all over the world.

        One project is to use the water in the storm water canals, treat this water and store it in multiple man-made structure like reservoir. We mostly all use man-made structure for water distribution in the developed world. The issue with putting the treated water in the aquifer is that if the treatment went wrong, it contaminates the entire aquifer. The entire aquifer would be unusable.