Low hydrant water pressure hampers firefighters’ work

Tuesday, Nov. 4, 2003 | 9:52 a.m.

Las Vegas firefighters' efforts battling a three-alarm fire that destroyed a vending company building early Monday were complicated by low water pressure in area hydrants -- and other local fire officials have reported similar problems.

Las Vegas Fire Department Deputy Chief Jeffrey Morgan said that low water pressure from hydrants, high winds and tight access in the industrial area combined to hamper firefighting efforts in the blaze at Sky Top Vending, 1509 Western Ave.

The fire, which caused $1 million in damage, might have been started by homeless people trying to keep warm with a fire, investigators said.

About 20 fire vehicles, including four large ladder trucks, along with 80 firefighters from city and Clark County fire departments, responded to the call shortly before midnight Sunday. The blaze, confined to one building, was brought under control at 5:15 a.m. Monday.

Las Vegas Valley Water District spokesman J.C. Davis said that computer data shows that pressure was maintained in the lines to the hydrants during the fire.

But low pressure in fire hydrants could occur in underground lines or loose-fitting caps, fire officials said.

As they build new neighborhoods and business areas, developers install hydrants, and the fire department is responsible for checking them. The water district is supposed to maintain water pressure in the lines to specifications set by the fire departments and local governments, Davis said.

"In general, we try to maintain a range of 35 pounds per square inch to 80 pounds per square inch pressure to each line," Davis said.

Although Southern Nevada is entering its fifth year of drought, shrinking water supplies in the West do not affect the water pressure in those hydrants, Davis said. Reservoirs and pumps throughout the valley supply hydrants with water, he said.

Hydrants are tested each year by fire departments. In North Las Vegas hydrants that underperform during a fire a checked immediately after firefighters get the fire knocked down, Assistant Chief Terri Tarbett said Monday.

Hills and valleys could across the city, demand on the water supply and problems with lines underground all contribute to how forceful the water streams from firefighters' hoses, Tarbett said.

"Gravity plays a part," Tarbett said, noting most people do not realize how much the ground rises and falls across the valley, which slows water flow naturally.

If firefighters find a hydrant with low pressure, a pumper can boost the flow or a crew can tap another supply line, she said.

"If you just keep stealing and stealing the water, you deplete the water line," Tarbett said.

Clark County Fire Department spokesman Bob Leinbach said low pressure occurs in unincorporated areas of the county at times.

"We test hydrants as often as we can," at least once a year, he said. "We check them when we find a problem with one."

Construction companies can tap fire hydrants for water if they meter the water they use and pay for it. Sometimes those workers leave a loose cap on a hydrant, which can create a drop in pressure, Leinbach said.

"I haven't done a scientific study of it, but out of all these tens of thousands of hydrants out there, there is going to be a drop in pressure in some of them," Leinbach said.

Henderson is different from Las Vegas, Clark County and North Las Vegas in that it has its own water department, Deputy Fire Chief J.T. O'Neal of Henderson's Fire Safety and Prevention Division said.

Henderson integrates the water supply through its reservoirs and piping, he said.

"We don't have a lot of water in the desert, so we have to store it," O'Neal said.

If a hydrant experiences a drop in pressure, Henderson supplies the line from two different directions, boosting the water flow, O'Neal said.