A newsreel from the 1940s shows the drinking water of Lima, Callao, and its coastal resorts. It reports that the water is considered to be of the highest quality in the Americas, thanks to its rigorous treatment. The footage shows the coarse sedimentation tanks and the laboratory where the water undergoes further clarification. In 2 hours and 40 minutes, the water has passed through these tanks, achieving complete clarification. The bacteriologist then examines the purified water, and once its excellent quality is confirmed, it is distributed to large reservoirs for human consumption.