Scott G Winterton, Deseret News
FILE - Residents of Hildale, Utah, and Colorado City, Arizona, watch as work goes on Tuesday, Sept. 15, 2015, to clean debris after a flash flood. A memorial service is planned later this month for the one-year anniversary of fatal flash floods that ravaged a polygamous community on the Utah-Arizona border, killing at least a dozen people.

SALT LAKE CITY — A memorial service is planned later this month for the one-year anniversary of fatal flash floods that ravaged a polygamous community on the Utah-Arizona border, killing at least a dozen people.

The Spectrum newspaper in St. George reports (http://bit.ly/2c6MrN0 ) that Terrill Musser says the service Sept. 14 at 6 p.m. in Colorado City's Cottonwood Park. Musser is a member of a community group planning the event.

On that date in 2015, two cars with three women and 13 children inside were swept away by a wall of water and into a flooded-out embankment. Three boys survived. One boy, who is presumed dead, is still missing. The bodies of 12 others were found amid mud and debris miles away.

The same storm killed seven hikers who drowned in a narrow canyon in Zion National Park and a man from nearby Hurricane, Utah.

Information from: The Spectrum, http://www.thespectrum.com