4,000 cubic feet surge hits Prescott

Water flowed at more than 4,000 cubic feet per second into Watson Lake Dam before the surge began to recede. This peak inflow followed days of heavy, continuous rainfall that saturated the ground in the mountains. The saturation produced two to three times the usual runoff volume.

Prescott Mayor Cathey Rusing declared a state of emergency on Sunday. Water spilled over the top of Watson Lake Dam, also known as Granite Dam. The city opened its Emergency Operations Center at 8 a.m. to coordinate the response. Municipal departments are working alongside Yavapai County and the state of Arizona.

City officials stated the dam is rated to handle water flowing up to 10 feet over its crest. They are continuously monitoring the structure for problems. Current flows have dropped to roughly 1,680 cubic feet per second. Prior to the storms, Public Works opened a 36-inch release valve and the crosscut channel to Willow Lake. These actions lowered the reservoir to create space for incoming stormwater.

Upper Goldwater Reservoir has also topped. The city is closely monitoring Lower Goldwater Reservoir. Willow Lake Dam sits 7.5 feet below its spillway, and officials report no structural concerns there.

The National Weather Service issued a Flood Watch for Yavapai County on Thursday, October 29. The watch covered Saturday evening through late Sunday night. It warned of flash flooding caused by heavy rain falling on already saturated ground.

All low water crossings in the city are closed. Specific road closures include Sixth Street and Sonora Drive at Campbell Street. South Granite Street is closed between West Aubrey and West Leroux streets. Walden Road is closed off White Spar Road, and Brannen Avenue is closed at Miller Valley Road. Granite Creek Park is closed. Several traffic signals lost power, and drivers must treat dark signals as four-way stops.

Sand and sandbags are available at three fire stations. Locations include White Spar Fire Station at 333 White Spar Road, Airport Fire Station at 1980 Club House Drive, and CAFMA Fire Station 51 at 1700 Iron Springs Road. Residents must bring their own shovels and fill their own bags. Yavapai County and the American Red Cross opened a shelter at the Yavapai College Prescott Campus Gymnasium at 1100 E. Sheldon. The non-emergency flood phone bank is 928-442-5103.