Study: Developers responsible for LV’s dusty skies

Monday, Sept. 9, 1996 | 11:59 a.m.

When David James decided to find out why there's so much dust in the Las Vegas Valley, he captured it in a portable wind tunnel.

There's more dust in Southern Nevada these days because more people are disturbing the desert soils, said the assistant professor in civil engineering at UNLV.

Clark County planners estimate 14,000 acres are under construction in Southern Nevada today. That's almost three times the acreage that was under development 10 years ago.

As James and his students are discovering after analyzing what they collected last year, about half the dust blowing across the valley comes from construction sites.

Built in portable parts by graduate engineering student Joe Haun and stored in red wooden boxes at UNLV's Howard Hughes School of Engineering, the portable wind tunnel sent James and his students into summer's heat to capture dust clouds.

Of nine types of soil found here, two kinds protect themselves and do not raise dust unless disturbed.

One type forms the hard surface of desert pavement, formed after winds blow loose particles away. But if bulldozers or off-road tires crack through the surface, the desert's pavement goes airborne with winds above 15 mph.

Another type, found in the northern and northeastern parts of the valley, forms a hardened surface after brief rains or water fall on the soils made of clay.

When the layer dries out, it cracks and forms a pattern like the bottom of a dry lake bed, James explained. Except the Las Vegas Valley is not a dry lake bed, he noted.

It's not the particles raising a cloud of dust that could threaten human health, he said.

Instead, he said, it's the invisible particles that work their way down into people's lungs that can cause health problems.

Although James is still preparing his $64,000 report for the Clark County Health District, some of the suggestions include reducing traffic and planting grass on empty lots until they are developed. The grass idea came from Ron Wilson of the Soil Conservation Service.

James said developers sometimes strip 100 acres although they have an immediate use for only 10 acres. If developers planted grass on the other 90 acres and watered it once, the grass -- once it died -- would stop loose dust, he said.

Other ideas include paving or oiling dirt roads.