Environmental study says building ‘critical’ St. George highway would spread weeds, cause fires and threaten tortoises

Washington County officials are threatening legal action if right-of-way for the highway is revoked

St. George • Building a major highway through a national conservation area in southwest Utah would increase the spread of noxious weeds, spark more wildfires and increase the risk to Mojave desert tortoises and other endangered species.

Those are some of the findings outlined in a Supplemental Environmental Impact Statement (SEIS) the Bureau of Land Management and U.S. Fish and Wildlife Service released this week to assess the impacts of putting a four-lane highway through the Red Cliffs National Conservation Area (NCA), which is situated just north of St. George.

In January 2021, the Trump administration approved the right-of-way for the controversial North Corridor Highway. That triggered a lawsuit by Utah and national environmental groups who accused the U.S. Department of Interior and the BLM of violating federal law, including the Endangered Species Act and the National Historic Preservation Act.

Citing flaws with the original environmental impact statement, U.S. District Court Judge Amy Berman put approval of the highway on hold in November to provide federal agencies an opportunity to reexamine its impact on the Mojave desert tortoise and conduct a supplemental EIS that would build on the original.

With the draft SEIS being published today in the Federal Register, the public has 45 days to comment and provide feedback. That will be followed by the release of a final SEIS and a decision regarding the proposed highway.

Fallout over report

While a final determination on the highway is likely several months down the road, fans and foes of the Northern Corridor are already weighing in on the findings in the SEIS.

“The Biden-led BLM’s approach on this important issue has been beyond frustrating,” Washington County officials stated today in a news release. “Rather than supporting the existing right-of-way, which has been amply studied, the BLM is promoting half-baked alternatives and concepts that will significantly harm the quality of life for Washington County’s human and Mojave desert tortoise populations alike.”

Added Washington County Commissioner Adam Snow: “We have been studying, planning, and fighting for this highway for over 15 years. The Northern Corridor is absolutely critical to our county. It must be built and it must be built the right way.”

Highway supporters argue the road will reduce traffic congestion in the St. George area by up to 15%. They are worried that the draft SEIS doesn’t name a preferred route for a northern corridor highway and puts four previously abandoned alternative routes back into play. Even more worrisome, they add, is that the document adds an option to revoke the right-of-the-way for a northern corridor highway.

“Obviously, the BLM’s preferred alternative is to undo the right-of-way for the highway,” Washington County Attorney Eric Clarke said, characterizing the SEIS as a subterfuge to reach a predetermined decision to kill the highway altogether.

Conversely, environmental and conservation groups see things differently. Todd Tucci, senior attorney for Advocates of the West, said the SEIS shows cheatgrass and wildfires are exploding in the NCS and that the original EIS underestimated the proposed road’s impact on tortoises, whose population density has declined in the core area of the NCA from about 30 to 10 adult tortoises per kilometer over the past 25 years.

“My big takeaway on the SEIS is that [federal officials have] erected a mountain of objective, scientific evidence that demonstrates the highway’s impact on the Mojave desert tortoise would be even greater than we thought before,” Tucci said.

Holly Snow Canada, executive director of Conserve Southwest Utah, argues building a major highway through a national conservation area is not the answer to easing traffic gridlock.

“There are better transportation options that exist than the Northern Corridor Highway route that serve our growing community needs while protecting wildlife and the scenic values that make our area such a special place …,” she said in a news release.

The Red Cliffs NCA is encompassed within the 69,000-acre Red Cliffs Desert Reserve, which was created in 1996 to recover desert tortoises threatened by development. The reserve is administered by the county in collaboration with federal agencies as part of a compromise that protects 61,000 acres of public lands for the Mojave desert tortoise. In exchange, the agreement opened up roughly 300,000 acres of tortoise habitat on private and public land outside the reserve for development.

Transportation alternatives

As currently proposed, the 4.5-mile North Corridor Highway would cut across the NCA and link Red Cliffs Parkway on the west with Washington Parkway near I-15 on the east. The SEIS lists two alternate routes that would also encroach into the conservation area.

One is the T-Bone Mesa alignment, a more northerly route that would connect Green Springs Drive on the east with Red Hills Parkway on the west just north of the Pioneer Hills trailhead. The other is an alignment near the NCA’s southern border that would link Green Springs Drive on the east with the Red Hills Parkway on the west just south of the Pioneer Hills trailhead.

According to the SEIS, all three of these northern corridor alternatives would destroy tortoise burrows and habitat and contribute to the spread of invasive plants, which would increase the probability of wildfires. That, in turn, would lead to even more noxious weeds and invasive species, thus accelerating the fire risk even further. In addition, all three Northern Corridor alternatives could have adverse impacts on a number of historic properties.

Another two alternatives the SEIS identified fall outside the NCA. One would convert Red Hills Parkway in St. George into an expressway between Interstate 15 and Bluff Street that would facilitate better east-west traffic flows in the area. A second route would convert St. George Blvd. and 100 South in St. George into one-way streets.

Both these non-Northern Corridor alternatives would not impact any additional tortoise habitat, but the Red Hills route could negatively affect vulnerable Virgin thistle plants and two historic properties, according to the document. If either St. George alternative or the option to terminate the Utah Department of Transportation’s right-of-way for the North Corridor Highway are selected, that could also pave the way for the loss of tortoise protections and habitat elsewhere.

In 2021, Zone 6 was added to the Red Cliffs Desert Reserve to offset the impact that would result from building the North Corridor Highway. The land — roughly 6,800 acres evenly split between the BLM and the Utah Trust Lands Administration — is located west of Bloomington and is separate from the rest of the reserve.

If a St. George or the termination alternative is selected, according to the SEIS, Zone 6 would be eliminated and the 3,338 acres that SITLA now owns could be opened up for development. That could not only have repercussions for the zone’s Mojave desert tortoises but also for Parry’s sandpaper and endangered dwarf bear-poppy plants in the area. It could also lead to damage from “unmanaged motorized” activities, a greater risk of wildfires and the complete loss of habitat from development.

Wishful thinking, weighing the options

Still, conservationists and environmentalists insist, the negative impacts of building a Northern Corridor road far outweigh any positives.

“This highway is an ill-conceived idea that needs to go away once and for all,” Desiree Sorensen-Groves, vice president of land and habitat conservation for Defenders of Wildlife, stated in the news release.

However, Clarke said that might be wishful thinking. He argues the Omnibus Public Management Act Congress enacted in 2009 authorized the construction of and allow the public east-west highway across the county. If the federal government nixes a North Corridor route, he doesn’t expect the county or the state to accept the outcome.

“We could wait till we have a friendly administration and reapply again. We obviously are also gearing up for a potential lawsuit.”

The BLM is taking public comment on the draft SEIS until June 24. It will also host a public meeting, at a time and place to be announced later, to give the public an opportunity to ask questions and provide feedback.

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