One interesting thing my family and I noticed while in Peru was the irrigation system used for the maintenance of the parks throughout Lima (though in many ways Lima is the dirtiest city I can remember being to, in the more affluent areas there are some very beautiful green spaces). By far the most common system of irrigation used is a flooding method in which a large trench (or, for a large park, multiple trenches) is dug, often with slightly shallower offshoots radiating away from it. Water is then poured into the trench until it fills to the brim, at which point the water seeps into the ground on either side and provides moisture for the soil. There are several problems with this method.
To start, the trenches look rather unpleasant and the ground next to the trenches is a sopping mud soup following a flooding. They also make any traversal of a park at night or in the late evening rather treacherous. However, beyond the aesthetic and somewhat overly safety conscious attitude I have developed from spending most of my life in North America (especially those four years in Pennsylvania where we couldn't have a swimming pool on our property without an unhealthy dose of insurance on the off chance someone trespassed and drowned), my main issue with the irrigation method is it seems ridiculously inefficient, especially when conducted in the heat of the day. One would think that in a desert city, the issue of water efficiency would matter. No one there seemed concerned, however, so I suppose they know something I don't.