Tropical Storm Allison dumped up to of rain on parts of the city over a five-day period in 2001, and was the most destructive and costly natural disaster in Houston history prior to Hurricane Harvey. Area flooding was catastrophic and widespread. The storm completely overwhelmed the flood control system and caused 22 deaths in Houston and $6.05 billion (2006 USD) in damage. It was the only tropical storm in history to have its name retired until Tropical Storm Erika in Dominica in 2015.