US 93 wildlife crossing honored with environmental award

US 93 wildlife crossing honored with environmental award


US 93 wildlife crossing honored with environmental award

US 93 wildlife crossing honored with environmental award

September 13, 2011

US 93 - Wildlife Crossing
          Photos courtesy of the Arizona Game and Fish Department

Over the past several years, ADOT has worked to transform the highly traveled US 93 between Wickenburg to the Hoover Dam from a two-lane highway to an environmentally friendly four-lane, divided highway.

A project of this scale will always present its share of issues, but widening the final section – from Kingman to the Mike O’Callaghan - Pat Tillman Memorial Bridge – provided ADOT with an especially unique challenge …

That final stretch also happened to be the stomping grounds of the country’s largest contiguous herd of desert bighorn sheep.

Without some sort of solution, motorist safety would be at risk from the substantially increased chance of wildlife-vehicle collisions. But the sheep still needed to be able to cross the highway in order to reach essential resources on both sides.

Wildlife overpasses were thought to be the obvious fix … but, where should they be built along this 15-miles of new roadway?

To answer that question, ADOT worked with a number of state and federal agencies in a collaborative partnership to seek locations where the sheep were most likely to cross the highway. The Arizona Game and Fish Department, National Park Service, Bureau of Land Management and the Federal Highway Administration were all part of the effort.

The team was able to track the animals by placing electronic collars on them and using global positioning system tracking units to trace their movements over an extended period of time.

This research helped identify the most appropriate crossing locations for the herd. Three specially designed overpasses for bighorn sheep – the first of their kind in Arizona and the lower 48 states – were constructed, along with fencing, as part of the highway expansion.

The project has been successful. Cameras installed on the crossing bridges captured the desert bighorn sheep using the new overpasses, which are 100-feet wide and 203-feet long and the Federal Highway Administration awarded ADOT one of its top environmental honors, the 2011 Exemplary Ecosystem Initiative Award, for the successful completion of this project.

ADOT’s Director of Environmental Services Todd Williams says the project was truly a joint effort of the multiple agencies involved.

“Without their support and teamwork, we would not have been able to accomplish as much as we did,” he said. “This new section of divided highway in this environmentally sensitive area delicately addressed two critical issues: the safety of the traveling public and the need to preserve the livelihood of the Desert Bighorn Sheep, which are native to the Black Mountains. These new wildlife overpasses helped accomplish both objectives on this project.”

Thousands of tumbling tumbleweeds roll into wash

Thousands of tumbling tumbleweeds roll into wash


Thousands of tumbling tumbleweeds roll into wash

Thousands of tumbling tumbleweeds roll into wash

August 23, 2011

Tumbleweeds on SR 87

An ADOT Highway Operations Supervisor came across a sight Monday morning that he’s never seen before …

As he was driving by Jeddito Wash on SR 87, Elliott Koinva noticed that thousands of tumbleweeds had clustered together to form a kind of solid wall.

“The wash is about 15 feet deep and about 20 feet wide,” Koinva said. “The whole wash was filled with tumbleweeds.”

He suspects an overnight storm north of the wash must have carried the tumbleweeds down. There were so many tumbleweeds that a box culvert got clogged and some flooding occurred.

Although there normally are a lot of tumbleweeds in this area, near Second Mesa, Monday morning’s occurrence was something extraordinary.

“This was the first time this has happened,” Koinva said. “I was surprised.”

ADOT’s Holbrook District Superintendent Lindy Sherrer says ADOT crews will use pitch forks to start clearing out the box culvert. Because the area’s flooded, machinery won’t be used until some of the water drains away.

Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303

Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303


Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303

Enjoy the view - trees and cacti replanted to maintain the scenery on Loop 303

May 3, 2011

Cacti and trees replanted along the 303

This slideshow will give you an idea of how many cacti and trees were replanted along the new stretch of the Loop 303 last September.  The steps involved in removing just one saguaro from the on-site nursery and replanting it next to the road could sometimes take more than one hour. 

Who says constructing a freeway through a beautiful desert expanse has to spoil the view? 

Once the new stretch of Loop 303 opens this month, motorists will see for themselves that great care was taken by ADOT and its project partners to keep the scene as pristine and seemingly untouched as possible.

Native desert plants that lived in the path of the new freeway were not just pulled up and thrown away – they were uprooted, cared for during freeway construction and then replanted alongside the new road.

Crews began by taking an inventory of all the plants surrounding the 14-mile stretch of highway. There were saguaros, barrel cacti, several other cactus varieties, ocotillo, mesquite, ironwood and palo verde trees to contend with.

Landscapers decided which plants to salvage based on a variety of factors, including the plant’s species, size, health and aesthetic qualities. The saguaros and some of the other cacti are designated by law as protected, which means they cannot be allowed to succumb to construction projects.

A total of about 6,900 cacti and nearly 1,000 trees were tagged, dug up in such a way to preserve their roots and carefully replanted in three nurseries located on the construction site – the nearby location was good for the plants because they were already used to the site’s soil conditions.

Special care was taken to help keep the plants comfortable in their new, temporary home. Gravity-fed water systems were set up in the nurseries to ensure the plants thrived.

To assist in the transition back to their permanent spots along the 303, contractors saved the top layer of native soil from the roadbed and applied it to the slopes where a majority of the replanting occurred.

The forethought paid far, there has been a 90 percent survival rate for all the plants.

Outside contractors will care for the plants for the next two years. During that time, there also will be a temporary watering system in place alongside the freeway.

After the two years are up, the irrigation system will be taken out and the plants should be ready to make it on their own. The cost savings associated with this project include not having to install granite mulch, new plants and underground irrigation pipes and controls.

ADOT’s Chief Landscape Architect LeRoy Brady says he’d like to issue a challenge to people to watch as the vegetation stabilizes and adds to the area aesthetically.

He says that in addition to the replanting, all medians and roadsides have been hydro-seeded with 20 different species of plants – that means the area will continue to change, develop and grow more beautiful over time!