Water water everywhere...Or not.

"Sunny days, in and of themselves, don't kill people, but when people run out of food and water, they die." –Richard Gill. 

Before we review this very fitting quote in more detail, it is important to note the water sources for the Maya, especially since this plus water management greatly influenced human settlement across the Maya region.

Centote with cool deep fresh water. The Maya believed that
this water purified and replenished their health 

Northern Yucatan: Because of the limestone surroundings, much of the surface water that accumulated during the rainy season was percolated down into the ground, forming magnificent caves and cenotes (sinkholes) (see photo on the right) that were sufficiently shallow to be available for use (Webster et al., 2007). These caves are amazing and if you ever visit Yucatan part of Mexico do not pass up the chance to swim in the cenotes to avoid missing a truly sublime experience!

Southern Lowlands: In contrast to the north, the water table would have been too deep for access, and so about 95% of the Maya centres depended solely on lakes and rivers for drinking and agriculture, with an average water supply for 18 months (National Geographic, 2003). Therefore much of the Maya social innovation was concentrated on excess water storage for times of greater need. For instance, they created artificial reservoirs designed to trap runoff from rainfall. There is plenty of evidence that the Maya recognised the importance of a wetland biosphere, and managed to turn their artificial reservoirs into constructed wetlands with a balance of pondweeds, smaller plants and algae that worked together to purify the water. Through this, they maintained a clean water supply throughout the year (Lucero et al., 2011).

Effect of a long-term drought

The Maya could obviously adapt well to extreme seasonal changes and short annual droughts, so what on earth went wrong? It seems that despite the elaborate schemes described above, they still had a huge dependency on rainfall that made them susceptible to longer-term droughts (Webster et al., 2003). It is plausible the three severe droughts may just have pushed them over the edge. 

Such a change in climate would have impacted all the regions and their populations, as the water supply that fuelled the growth of their civilisation could no longer be relied upon. Without sufficient rainfall, agriculture would have been affected and food supplies would have consequently been reduced (especially since maize is a relatively thirsty plant), opening up a whole Pandora’s box of effects (Lucero et al., 2011). Needless to say, an attempt to increase harvested food would have led to environmental degradation and perhaps further deforestation. Additionally, the associated decline in water quality and would have led to an increase in water-borne diseases and pests. The first few posts of this blog discusses such problems in more detail; drought would most certainly have exacerbated these.