110922

As the Arizona Department of Transportation starts work on the  I-17 Improvement Project from Anthem Way to Sunset Point, it is taking steps protect the natural landscape along this stretch of scenic highway corridor as well. 

[Above photo by the Arizona DOT]

The agency said its work crews are removing native vegetation – including saguaros, palo verde trees and ocotillos – from the 23-mile project corridor to temporary nurseries, before eventually replanting them alongside an improved and wider highway. 

Drivers who regularly travel I-17 between Anthem Way and Sunset Point may see some of what the Arizona DOT describes as “plant salvage” work during the next several months. Plant salvage crews from the Kiewit-Fann Joint Venture developer team will collect hundreds of viable native trees, “accents” (such as ocotillos and yuccas), saguaros and other cacti from the construction area. Altogether, roughly two-thirds of the right-of-way along the 23-mile project area will remain undisturbed, meaning no plant salvaging will be necessary.

“October is usually the prime time for salvaging the plant material, just because our temperature is not too hot and not too cold,” said David Casselbury, a landscape architect with Arizona DOT, in a statement. “We’re hoping the general public will enjoy driving along the highway and seeing this plant material back in its natural environment once the project is complete.” 

The salvaged trees and cacti are not the only plants returning to the natural landscape once the improvement project is finished, the agency added, as it plans to add native seed mixes and nursery-grown plants to the highway construction area. Those efforts help to achieve the long-term goal of successfully revegetating areas within the construction area considered “landscape-able” with a mix of plants that will thrive and restore the natural environment for years to come. 

Restoring native plants has been an integral part of many Arizona DOT projects for more than 35 years, according to the agency.

For example, Arizona DOT spent the last four years relocating a rare and endangered species of cactus growing near the Pinto Creek bridge replacement project along U.S. 60 near Globe-Miami. Initiated in 2018, this relocation effort is the latest step in a long-term partnership between the Arizona DOT and the Desert Botanical Garden in Phoenix to protect hedgehog cactuses that only grow in one tiny area of the state.

The agency also relies on ‘biomonitor’ teams from Northern Arizona University or NAU to help its work crews find and relocate endangered species – including snakes, birds and fish – from construction sites.

Specifically, those biomonitor teams train construction workers and other involved in transportation projects to identify any endangered species and what to do if they come across one. The teams also monitor construction activity and help safely remove any endangered species out of harm’s way.

The Colorado Department of Transportation recently began work on the I-70 Genesee wildlife-crossing project, one of several I-70 Floyd Hill projects to improve both highway safety and traffic flow ahead of construction on the $700 million main project.

[Above image by Colorado DOT]

The I-70 Genesee wildlife-crossing project consists of a dedicated wildlife underpass going under I-70 between the exits for Lookout Mountain and Genesee. Additionally, crews will place wildlife fencing along both east and westbound I-70 that extends from the Genesee Exit to the Lookout Mountain Exit.

The agency noted that this area has the highest number of wildlife-vehicle collisions on the I-70 Mountain Corridor east of the Eisenhower-Johnson Memorial Tunnel.

“The new underpass at I-70 Genesee is the first major wildlife crossing to be constructed along the I-70 Mountain Corridor, and it will allow wildlife to safely cross underneath the interstate at a location which has historically been a hotspot for wildlife related crashes,” said Colorado DOT Executive Director Shoshana Lew in a statement.

“Reducing animal-vehicle conflicts and improving wildlife connectivity is a major element to the overall improvement of travel time reliability, safety, and mobility in the I-70 Floyd Hill project area,” she added.

The plan calls for construction of two new I-70 bridges, followed by excavation under those bridges to create the wildlife underpass. Once the underpass is complete, crews will install the wildlife fencing. Altogether, bridge and underpass construction should wrap up by the spring of 2024.

To date, Colorado DOT has built more than 60 wildlife mitigation structures crossing above or under highways throughout the state. Additionally, it has installed 400 miles of high big game fencing along state and U.S. highways or next to the interstates.

In August, the agency completed the state’s newest wildlife overpass and underpass on U.S. Highway 160 in the southwestern part of the state.

In October 2021, Colorado DOT and the Colorado Parks and Wildlife agency completed wildlife underpasses along a rural stretch of Interstate 25 between Colorado’s two largest cities, Denver and Colorado Springs.

That wildlife mitigation system is part of a $419 million transportation improvement project – known as the I-25 South Gap project – that aims to improve safety and travel on 18 miles of I-25 south of the Denver metropolitan region; a route that more than 87,000 motorists use on a daily basis.