As California's four-year drought worsens and water supplies dwindle in the state, an old technology—railroads—could play a role in alleviating some water shortages.
"We certainly have that capability today," said Mike Trevino, a spokesman for privately held BNSF Railway, which operates one of the largest freight railroad networks in North America. "We carry chlorine, for example. We carry liquefied commodities."
Experts say the East Coast's plentiful water could cost cents per gallon to Californians and provide a stable, potable water supply for small communities. Obstacles include identifying a state willing to share some of its water, and securing the construction funds for key infrastructure work, including terminals that can handle water.
"We've actually spent some time on this and some energy, and there's merit; there's value for railroads to play a role in moving water."
"We've actually spent some time on this and some energy, and there's merit; there's value for railroads to play a role in moving water," said Ed McKechnie, chairman of the American Short Line and Regional Railroad Association.
Overall, McKechnie estimates it would cost upwards of $40 million to build the terminals needed to load and unload the water. He bases that figure on the investment for a similar facility to handle oil.
McKechnie, who also serves as executive vice president for short-line railroad holding company Watco Companies, said the estimated cost of the water would depend on how much is spent on construction. "It wasn't dollars per gallon," he said. "It was in the cents range per gallon."
Bulk water delivered by truck can run under 10 cents per gallon in parts of California's drought-parched Central Valley, but some of those supplies are at risk of drying up. The truck water tanks typically hold around 2,500 gallons, while each railroad tank car carries about 29,000 gallons, and sometimes more.
"We move trains that are 110 cars long with liquefied materials," said BNSF's Trevino. "There would be costs associated with shipping it, but those can certainly be overcome."
More from CNBC:
- Commentary: How to fix California's drought problem
- California farmers under attack for heavy water use
Trevino's not aware of any municipality or private enterprise that has approached BNSF about hauling bulk quantities of water. The railroad operates in the western half of the United States, so if the water were to come from the East Coast, it would likely require an eastern railroad, such as Norfolk Southern or CSX, to assist in the delivery.
During Union Pacific's quarterly earnings conference call last week, an analyst commented on how truckers were moving water into California and asked the railroad's management about water hauling. An executive essentially shot down the idea, saying: "I do not think that's material."
The concept of water by rail has historic precedent. Railroads with water tank cars played a role during earlier U.S. droughts, in the West, the Midwest and on the East Coast. Southern Pacific Railroad, which later became part of Union Pacific, was one of the railroads that hauled water in the late 19th century to small towns in California.
Only in modern times have arid communities been able to drill wells deep enough to pump water. If wells are running dry, or water isn't potable, the rail option could help for domestic use. But the idea faces big challenges.
According to California historian Richard Orsi, "It was extremely expensive to deliver it even then, and railroads only did it for their own operations and economic stimulus plans for their regions. It seems to me, that if this importing is indeed done, it would require vast infrastructure, and finance systems that I can't see actually emerging in this fractious, politically divisive society we live in."