Objective: Determine how many hectares the Presa de Trigomil increased following the incident in 1991 when it reached its max capacity flooding the nearby ranch towns.

Background information:

In January 1991, the dam ‘Presa de Trigomil’ in Jalisco, Mexico reached its max capacity well before the expected time period. The dam capacity is 250.1 cubic hectares. The dam was supposed to reach its capacity in 3 years but reached it in 1 month due to a heavy rain season. This caused residents to leave their ranch homes much earlier than they anticipated. In minutes families had to flee their homes to reach higher land. Human lives were lost and many livestock drowned. They moved to a nearby town where the government had already started to build homes for them. Like many dams the Presa of Trigomil was built for economic growth, it is filled with fish that can only be captured by designated fisherman unions. There are benefits to Dams but they also pose a hazard to nearby communities. I conducted an supervised classification to calculate the water surface before and after the dam broke.

Tool/Skills used: 

• Identified best band combination

• Classification Wizard 

• Polygon Creation