Amid a Natural Gas Boom, West Nile Cases on the Rise

Most of Don Spellman’s 8,000 acres in the Powder River Basin are rolling, treeless and, for the last several years, bone dry. But shimmering behind him as he drives fence posts into the hard-packed clay is a narrow, shallow lake that seems to spring from thin air.

The water, a byproduct of booming natural gas production in the Rocky Mountain West, is also host to millions of mosquitoes. And it may be the solution to a medical puzzle.

West Nile virus, which can sicken and kill people and animals, began its march across the United States in 1999. Scientists initially expected the disease, transmitted by mosquito bites, to stall west of the Mississippi, where sources of standing water are scarce.

Instead, it has thrived. Ten of the states with the most illness per capita are west of the Mississippi. Eight are in a prolonged drought.

Four -- Wyoming, Colorado, Montana and New Mexico -- are experiencing a boom in natural gas production. The gas is forced out of underground coal beds by pumping millions of gallons of underground water to the surface. The process leaves warm, shallow ponds -- ideal breeding grounds for mosquitoes -- scattered across the usually arid landscape.

Scientists studying the infection are not yet ready to declare the case closed. But as researchers trace the possible link between natural gas production and the illness, places such as Campbell County in northeastern Wyoming, which has nearly 13,000 coal bed methane wells, have become open-air laboratories.

This summer, researchers from two universities are testing water sources in the region, including natural gas discharge ponds, for mosquitoes that spread West Nile.

There are thousands of such ponds in Campbell County -- one of the driest in Wyoming. Last year, the county of 33,600 people recorded the state’s second-highest number of cases of West Nile infection, with 66. Wyoming had 373 human cases in 2003, the sixth-highest rate in the nation.

Coal bed methane wells are by no means the only source of standing water in a region that depends on widespread crop irrigation. But in Campbell County and the surrounding Powder River Basin, gas production pumps out 60 million gallons of water a day, outstripping agriculture’s contribution to standing water.

Moreover, hydrologists note that -- unlike seeps, springs and irrigation ditches -- discharge ponds related to natural gas production are present even in the dry summer months when other standing water often evaporates.

“Common sense tells you that if you’ve got that many water sources that were not there before, they are going to create mosquitoes,” said Terry Creekmore, West Nile coordinator for the Wyoming Department of Health. “Coal bed methane water sources in July and August are going to be a big part of the mosquito production.”

Domestic energy production has been a priority for the Bush administration, with gas drilling permits across the Rocky Mountains on a fast track. The Washington, D.C., office of the Bureau of Land Management has ordered all state offices to expedite oil and gas permits. The Powder River Basin has the highest concentration of coal bed methane development in the United States.

Don Likwartz, Wyoming’s oil and gas supervisor, said his office was approving 25 new drilling permits a day. More than 51,000 additional wells are projected to be in production in the basin in the next 10 years.

Ranchers and environmentalists in the region were bitterly critical of the coal bed methane boom before West Nile became an issue. At first, their main concern was that water pumped to the surface was sometimes so toxic that it destroyed grass and other plants on which livestock and wildlife depended. Now, they fear that the discharge ponds will put their health at risk.

Spellman’s ranch was one of the places where mosquitoes trapped by researchers around coal bed methane discharge ponds last summer tested positive for West Nile.

Spellman, a lifelong resident of the area, said that since coal bed methane production began a few years ago, he had noticed “50 to 100 times” more mosquitoes.

As he watched his border collie, Suzy, splash into a discharge pond on his ranch, he recalled a bizarre sight there last summer.

“From the surface to about 20 feet in the air, something was just bouncing up and down,” Spellman said, shaking his head at the memory. “It looked like there was a water sprinkler on. But it was mosquitoes. Millions of them. They must have just hatched.”

On his ranch, only birds have been affected by the virus thus far. Indeed, the discovery of infected sage grouse last summer was one of the first signs the disease had arrived. The grouse, which nests in sagebrush and is native to Western prairies, has been in decline for many years and is a candidate for the endangered species list.

Researchers examining birds that had been fitted with radio collars determined that 90% of sage grouse nesting near coal bed methane ponds in Campbell County had died of West Nile, while none of the hens nesting away from those water sources had contracted the virus.

Testing for the virus near coal bed methane sites, which began in Campbell County, is now going on in parts of Montana and Alberta, Canada, where natural gas is also taken from coal beds. The research is being sponsored by the BLM and the energy industry.

In Wyoming, researchers in Campbell County are extracting mosquito larvae from water sources -- methane discharge ponds, natural springs and stock ponds -- and testing for West Nile. The method, scientists say, provides conclusive proof of the origin of the infected mosquitoes.

Experts on West Nile say the type of mosquito found across the West, Culex tarsalis, is the “perfect vector” for passing along the disease -- more efficient, and therefore more troublesome, than Eastern mosquitoes. In addition, the large numbers of birds and other forms of wildlife found in the rural West can allow the disease to spread more rapidly.

Melissa Kuckler, a graduate student in entomology at Montana State University, is conducting the field research for one part of the BLM-sponsored study. She sets out 10 traps a day on ranchland across Campbell County and sends the larvae to a lab for testing.

Preliminary results are expected at the end of the year. Officials at the BLM office in nearby Buffalo, Wyo., said they would take the study into account as they considered new drilling permits.

“Let’s look at it. There is very little standing water in Campbell County,” said Kirk Miller, a hydrologist with the U.S. Geological Survey in Wyoming. “There are small ponds and such, but the source of water for a lot of the basin is groundwater, not surface water. The onset of West Nile to this part of the country is contemporaneous to the rapid development of coal bed methane.”

Michael C. Caskey, chief executive of Denver-based Fidelity Exploration and Production Co., said his firm was considering placing chemicals in its discharge ponds to kill mosquito larvae.

“We’re just in the throes of looking at it and testing,” Caskey said. Fidelity operates about 1,000 coal bed methane wells in neighboring Sheridan County. “But we don’t believe there is a connection per se with the water resource we’re developing and the other water in the area. Nothing has been proven.”

But even as industry leaders say they are skeptical of the connection between West Nile and natural gas production, at least one gas company recently sent letters to landowners informing them they would place larvicide in discharge ponds.

“It’s about being good neighbors. We’re working on it,” said Dru Bower, vice president of the Petroleum Assn. of Wyoming.

For now, treatment of standing water produced by natural gas development in Wyoming is voluntary. Neither the BLM, which administers federal permits, nor the Wyoming State Oil and Gas Conservation Commission, which issues drilling permits on state and private land, requires any form of mosquito abatement on discharge ponds.

“I’ll be honest with you; I guess our position is we are not really sure if you can blame the coal bed methane situation for any increase in West Nile virus occurrence,” said Michael Madrid, the BLM’s coal bed methane coordinator in Wyoming.

“It is an arid state; it does seem logical. It’s something that we probably didn’t consider as well as we should have. We’re trying to catch up.”