The 5th day of the 5th month of the 25th year of the 20th Century seemed like an ordinary day in the small town of Siaton , Negros Oriental. But, at exactly 5 o'clock p.m. of that day, dogs started howling, horses and caged birds became restless as if wanting to hastily escape. Their sixth sense was telling them that something unusual was about to happen.

Suddenly, right after an eerie silence, a strong earthquake registering 6.8 on the Richter Scale shook the town. It was followed by a frightening, thunderous sound which turned out to be a massive landslide felling centuries-old trees and house-sized boulders on both sides of the Balanan and Nasig-id ridges. That instant, the walls of the Roman Catholic Church of Siaton also collapsed. The landslide created a natural dam, now aptly called Sampong (meaning “to close”) across the Balanan River , causing the water to rise and create what is now called the Balanan Lake.