Yavapai County officials are in the midst of a multi-year project to update floodplain maps, and any changes could have huge impacts on some property owners.
People who want to build structures in floodplains have to follow special rules to make sure their homes or businesses are safe.
They also are required to have federal flood insurance in high-risk areas.
People can sometimes save substantial amounts of money by obtaining flood insurance before their property is officially added to floodplain areas. There's usually a 30-day waiting period before flood insurance goes into effect.
That's why the Yavapai County Flood Control District is going out of its way to notify people in Black Canyon City that the county will adopt new floodplain maps for the Black Canyon City area on Thursday, Oct. 16.
The county sent out postcards to nearly 700 property owners Monday who have property in the 100-year flood hazard areas in Black Canyon City, Flood Control District Director Dan Cherry said.
Coincidentally, parts of Black Canyon City flooded the following day when more than five inches of rain fell.
The Yavapai County Flood Control District also happens to operate numerous rainfall gages. Cherry said its two working gages in Black Canyon City registered 4.9 inches and 5.7 inches of rain Tuesday.
While most of the 700 property owners who received postcards already had property in the flood hazard zone, those who are new to the zone can save money by getting flood insurance before Oct. 16, Cherry explained.
Numerous other parts of the county will have updated floodplain maps within a few years.
"We're kind of slowly going through our larger floodplains," Cherry said.
They include parts of the watersheds of the Verde River, Big Bug Creek and Big Chino Wash; and the communities of Yarnell, Peeples Valley, and Williamson Valley.
The county finished remapping the Lake Montezuma area in December, and next year officials will start remapping the Oak Creek Watershed.
The Verde Watershed remapping is finished but the county is waiting on the Federal Emergency Management Agency (FEMA) to add some tributaries, Cherry said.
While the Verde mapping isn't officially finalized, the county is strongly recommending people to follow the rules in the new maps, Cherry said.
"It's in the best interest of everybody involved to use the latest information," he said.
The older maps usually date back to the 1980s when little of today's technology was available, he noted.
The district now has Board of Supervisors approval to view aerial maps for better accuracy, and next month it will be seeking approval to pay for downloading and using those maps, Cherry said.
People can find a wealth of information and links about flood insurance on the Flood Control District's website at ycflood.com. The site also allows users to view maps showing whether their properties are in floodplains.
The federal government has flood insurance information online at floodsmart.gov.
The federal government is the only place to get flood insurance, although some insurance companies help property owners. FEMA is trying to align its costs with risk, so people who build in high-risk floodplains could face huge premiums, Cherry said.
People who have loans through federally regulated or insured lenders for buildings in high-risk areas are required by the federal government to have flood insurance.
People outside these areas only need to look at this week's Arizona news to realize that lower hazard areas also can flood.
Nearly 30 percent of all flood claims in Arizona occur in moderate-risk and low-risk areas, information on the Flood Control District website states.
The average flood claim in Yavapai County since 1978 has been higher than $96,000, an amount few people have in the bank.
Follow Joanna Dodder on Twitter @joannadodder.