LAS VEGAS (KLAS) — On July 8, 1999, the thunderstorms began in the Spring Mountains where they often do this time of year. But this day would be different. Three inches of rain fell in just two hours and the water started running to the east side of the Las Vegas valley.

Floodwaters ripped through the washes. It was so powerful it ate away the banks along the Miracle Mile Mobile Home Park on Boulder Highway.

“You had vast neighborhoods underwater, said Erin Neff of the Clark County Regional Flood Control District. “You had parts of the Strip shut down. I mean when the casinos stop gambling, it’s a big event.”

The storm caused $20 million in damage, killed two people and led to hundreds of rescues.

A woman trapped in floodwaters on top of her car is rescued during the 1999 flooding. (Clark County Flood Control District)

Neff says there were countless big floods before flood controls ever existed.

“Before Las Vegas was a city, the water came from that side of town all the way down to the lowest point, which now is what is Lake Mead,” Neff said. “We had tremendous casualties back then, injuries, accidents.”

Since 1960, flash flooding has killed 33 people in Clark County. As the valley grew, residents went to city and county leaders for a solution and in 1987 the regional flood control district was born.

“They had the foresight. They actually said, ‘raise my taxes,'” Neff said.

And it worked. Today, one quarter of a penny of county sales taxes adds up to about $100 million a year to spend on the master flood control plan. But there have been growing pains along the way.

A car caught in floodwaters during the 2003 storm. (Clark County Flood Control District)

August 2003 brought another devastating storm day for the history books. Three inches of rain in 30 minutes, this time in the northwest. The storm sent walls of water crashing through valley neighborhoods closing U.S. 95 and stranding thousands of drivers across the valley.

Flooding during a 2003 storm caused damage around the valley. (Clark County Flood Control District)

And not every corner of Clark County will have flood protection, for example, rural areas.

And on a rainy September day in 2014, summer thunderstorms opened up over the mountains near the rural town of Moapa, northeast of Las Vegas.

“What happened in Moapa was incredible. We had rain gauges showing four inches of rain in the afternoon. And so all that water just flowed right down on the I-15. It ate a hole in the interstate in just an hour,” Neff said.

Floodwaters in 2014 tore flooded I-15 near Moapa and tore away a section of the freeway. (KLAS-TV)

It took a week to repair I-15. Flood control is now in place.

And in August 2013, tremendous thunderstorms in the Spring Mountains after the Carpenter One fire sent torrents of water, mud and ash flowing into the newer northwest neighborhoods around Grand Teton and Buffalo drives before flood controls had been built.

“They were approving housing subdivisions left and right when the economy went sour. The developers said, ‘Well, we don’t have the money to do the flood control portion,’ and that’s actually what happened with Grand Teton,” Neff said.

To date, $100 million dollars has been spent in that area to help shield homes from flooding, and the work isn’t done. So far, 650 miles of channels and wash improvements have been completed with 100 detention basins.

So what happens when we get the next 100-year storm like the one 21 years ago?

“We design every one of our facilities to meet that level storm. So, everything that’s in place can handle that storm,” Neff said. “If the rain that happened July 8, 1999 happened this year, we would not have that kind of flooding.

Flood channels and basins around the Las Vegas valley help capture and direct the rainwater. (KLAS-TV)

The master plan is updated every five years with 25 years left to build 200 more miles of channels and another 36 detention basins. To date, more than a billion dollars has been spent on flood control, and Erin Neff says that more than 50 flood zones have been eliminated. That saves homeowners money on flood insurance and potential property damage.

Most importantly, it saves lives.