It must have been a time of total abundance and arrogance when they came up with the idea of concrete River beds to basically flush the water into the ocean cutting the fresh Rainwater and not even create some way to allow the water to flow down into the aquifer underneath the ground ...it's like they didn't know anything about nature back then there were simply so arrogant to think that they could defy God's plan & create a Tower of Babel so to speak
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Among the ideas being tried are slowly feeding rainwater underground, a process known as aquifer recharge, and creating more permeable surfaces where the water flows, such as removing some of the concrete around the Los Angeles River bed..."