WEBER COUNTY — One of the Great Salt Lake's most notable oddities, its two-toned color scheme, is drawing renewed attention.
The Union Pacific railroad plans to apply for permission soon to reconstruct portions of the company's 20-mile-long Great Salt Lake Causeway that stretches across the lake west of Ogden. Although it's a relatively small-scale project, the upgrade proposal is being watched closely by a variety of interest groups. That's because it may affect a decades-old imbalance of salt.
The salt discrepancy is visible to anyone who flies over the causeway. The water on the north side usually has a distinct reddish tint, while on the south side it's greenish-blue. The colors are attributed to different species of algae that thrive in different concentrations of salt.
The unusual color scheme is a direct result of the causeway. It's currently owned and operated by Union Pacific Corp., but it was originally built by Southern Pacific. "Southern Pacific built that causeway in the 1950s to retire the existing wooden trestle that was there," according to Dan Harbeke, Union Pacific director of public affairs.
The original trestle allowed water to flow freely under the railroad tracks, but the causeway that replaced it essentially acts as a 20-mile dam. The salt imbalance developed over many years because the south arm of the lake gets nearly all the freshwater. There are no significant creeks or rivers flowing into the north arm, while the south arm gets flushed continually by waters of the Jordan, Weber and Bear rivers.
Some water and salt flows back and forth between the two arms of the lake; the limited bi-directional flow is made possible by three gaps in the causeway; a breech at the west end that trains cross on a trestle and two large culverts further east on the causeway.
Now, Union Pacific has decided the culverts need replacement. Some interest groups see that as an opportunity to correct or improve the salt imbalance, but it's not clear if Union Pacific's plan will make a significant difference.
The railroad made a presentation several days ago to the Great Salt Lake Advisory Council. According to council chairman Leland Myers, Union Pacific presented only one option: constructing a single bridge 180 feet long, somewhere to the west of the existing culverts.
Some members of the council are concerned the location of the bridge might not allow for a big enough bi-directional flow. Myers said the council wants more studies to determine if the project will improve the salt imbalance or make it worse.
The Union Pacific proposal stems from a concern about ongoing maintenance of the culverts. They are deteriorating and sinking into the lake bed, according to one source who also said Union Pacific is concerned they could cause a "catastrophic" train accident.
Harbeke wouldn't confirm how serious the problem is, but he agreed there is a structural issue. "We have looked at the structural integrity in going forward," Harbeke said. "That's why we are submitting an application to the (Army) Corps of Engineers to replace those culverts."
Depending on how it's designed and what structures replace the culverts, the project might alter the flow rates of salt and water under the causeway. If the change is significant, it could have implications for various industries that depend on the lake.
Morton Salt, Cargill Salt, Broken Arrow Salt and U.S. Magnesium all use waters from the south arm and might benefit if salt is more evenly distributed in the lake.
On the other hand, Great Salt Lake Minerals Company benefits from the current imbalance by capturing the densest salt brines in the north arm. Dave Hyams, a spokesman for Great Salt Lake Minerals, said not enough is known about Union Pacific's plan for his company to take a position. But he said the minerals company has an interest in maintaining a "healthy" Great Salt Lake.
Conservationists who value the lake as a major habitat for birds would welcome a more even distribution of salt since it would be a return to a more natural ecosystem. They say if Union Pacific picks the right design for the revamp, it could help correct a half-century-old artificial oddity.
"Here is the golden moment for U.P. to do the right thing," said Lynn de Freitas, executive director of Friends of Great Salt Lake. "If nothing changes, it will turn into a challenge."
Another business that has a stake in the discussion is the brine shrimp industry. Don Leonard of the Utah Artemia Society said he has not heard details of what Union Pacific has in mind.
"The brine shrimp industry would be in favor of any measure that would assure the bi-directional flow of water between the north arm and south arm," Leonard said. Similar comments were voiced by Mike Legge of U.S. Magnesium.
Harbeke would not say what options Union Pacific is considering, but he said the company plans to file an application for approval by the Army Corp of Engineers sometime this month.
"And so while we haven't completed our application," Harbeke said, "I can't speculate at this time in terms of what those options might be."