Before McNary Dam was built on the Columbia River downstream of Kennewick, the river would periodically flood. The worst of these floods happened in 1948 and caused one death and $50 million ($533.6 million in 2019) worth of damage. The government responded by building the McNary Levee System to protect lower parts of town. Floods like this were the result of melting snow, and were most extreme when a heavy snowpack developed in the mountains over winter followed by a strong regional heatwave. The flood threat from the Columbia has significantly decreased since dams were built. Zintel Canyon Dam located near the Southridge Sports and Events Complex was built to protect parts of the city from a 100-year flood. While the creek that flows through Zintel Canyon typically runs dry, summer thunderstorms in the Horse Heaven Hills can generate destructive flash floods.