I’ve recently returned from a short stint in Merida, the Yucatan peninsula of Mexico. During my stay I visited both the site of Chichen Itza & Uxmal, both extraordinary in their own right.
The Mayan history lesson was interesting but what held my attention the most was the application of sustainable practices. Uxmal was constructed upon elevated foundations, those foundations contained water cisterns.

Surrounding structures incorporated gutters & swales were evident in the landscape. Those structures were made from stone found in the area. Interesting enough, the cisterns were also tiered, an overflow as such. Once the overflow reached the third tier that was a sign there was sufficient water for the crops & construction activities could begin.