Despite below average rainfall registered in Jalisco over the wet months of 2016, Lake Chapala has recovered enough water to supply Guadalajara for the next six years.
The lake gained 1.25 billion cubic meters (Mm3) of water to rise 1.18 meters in elevation between the first week of June and the official end of the rainy season in November, according to data released last week by the National Water Commission (Conagua). The increased volume is equivalent to six times the amount extracted each year for public use in the state capital.
Conagua calculates that Chapala loses 900 to to 1,400 Mm3 per year to evaporation, five to nine times more than the quantity of water drawn to feed the Guadalajara metropolitan area over 12 months. The evaporation process is considered essential to maintaining the region’s ecosystem and idyllic climate.
Overall, rainy season precipitation in Jalisco this year dropped about 10 percent below the historic norm. Rainfall measurements in the Chapala basin totaled 752 millimeters (mm), slightly below the 787 mm yearly average. The sum at weather stations in the metro area was 952 mm, versus the 970 mm average. Those figures are expected to rise from stormy weather during the final months of the year.