When the Spaniards started to settle the Bajio region in earnest after silver was discovered in Zacatecas and Guanajuato in the mid-1500’s, they found the land suitable for raising cattle and sheep and growing corn but not for much else because the rainfall was either insufficient or fell during too short a span of time.
The Spaniards missed their white bread from Spain. (No joke!) Wheat needed more rain than fell in the Bajio, so the Spaniards, with indigenous laborers, built extensive waterworks that included numerous dams and aqueducts or canals. The remains of these early irrigation systems can be seen across the rural landscape.
We had seen this handsome old dam many times and this week we forded the Rio San Marcos, a tributary of the Rio Laja, to paint Presa Santa Rosa and were rewarded with brilliant sunlight casting sharp shadows across this imposing structure. We both found this irregular structure with differently sized buttresses a challenge to draw.
What may have been a road or walkway across the top of the dam segments is long gone so we settled for this view from the riverbank and found a level spot from which to paint. Well, the level spot was, as it turned out, heavily trafficked by cattle that just moseyed right on through. I had to move quickly and couldn’t get a picture. Darn!!
I tried plein air pastels but had to redo from a photo so I added the errant cow this time.
But back to the irrigation systems…the Bajio region, a fertile basin covering most of Guanajuato, and parts of Querétaro and Michoacán, quickly became the breadbasket of the Mexican colonial economy. (The Spaniards wanted their white bread.) The increasing demand for wheat by Mexico City led to the expansion in the 17th and 18th centuries of irrigation based on run-of-the-river irrigation schemes in the Bajio region. Run-of-the-river refers to an irrigation system where a barrier is constructed across the river to raise its water level to such an extent that the flow is diverted into a canal system.
One such run-of-the-river irrigation system, highly developed in the Bajio, was the use of the seasonal floodwaters to flood embanked fields. These flooded fields were called cajas de agua (boxes of water) and varied in size from 5 to 200 hectares (12 to 500 acres). The fields were interconnected and could be drained from one to the other and, after being drained or after the water had soaked into the soil, sown with wheat. The floodwaters provided substantial nutrients to the soil and captured for agricultural use the limited, erratic and seasonal rainfall of the Bajio. (And, the Spaniards got to eat their white bread.)
The practice of filling these cajas de agua disappeared in the mid-twentieth century with the land distribution reforms that broke up the large holdings of the haciendas. One can pick out remains of the embankments that were part of these cajas de agua if you know what you are looking for.
© 2017 Lorie Topinka
Check out the following blog that has photos that show the subtle modifications to the landscape made by these cajas de agua: