Flood of 2002

• The Flood of 2002 was the first time that floodwaters flowed over the Emergency Spillway since the Reservoir was completed in 1964.
• The upper part of the Guadalupe River Watershed received more than 35 inches of rain in approximately one week. The runoff poured into the Guadalupe River and emptied into Canyon Reservoir, which was already above normal due to recent rains at the reservoir and because there was substantial flooding downstream. This downstream flooding made the Corps reluctant to release large amounts of water from the Reservoir, because it would likely increase flooding. (see Canyon Dam and Reservoir for more info)
• When the floodwater was at peak flow, it was moving at about 67,000 cfs*. Normal flow from the reservoir is 350 cfs.
• Just under 1 1/2 times the amount of water stored in the lake (at normal level) went over the spillway during the flood event.
• Water continued to flow over the Spillway for approximately 6 weeks.
• The Flood of 2002 is one of dozens of floods that the Guadalupe River has experienced. In 1998, only 4 years before the Flood of 2002, the Guadalupe River Basin DOWNSTREAM of the Dam and Reservoir experienced the most significant flooding in recorded history.
• The Guadalupe River Basin is a part of "Flash Flood Alley" and is one of the most Flash Flood prone river basins in the world.

* cfs = cubic feet per second