The 2006 monsoon in the Santa Catalina Mountains of Arizona brought intense rainfall in the second half of July. On July 31 storms and heavy rainfall produced massive flooding and debris flows in the mountains. These debris flows occur once in a 1000 years or more. Debris flows in the Sabino Canyon destroyed parts of the road and left others covered with rocks, boulders, and sand. Rattlesnake Canyon bridge was destroyed, but all nine fair-weather bridges in the Sabino Canyon survived.