PHOENIX – Following an independent study and public input, the Arizona Department of Transportation is raising the Interstate 17 speed limit south of Peoria Avenue to 65 mph.

The new speed limit will take effect when ADOT replaces the current 55 mph signs along I-17 between the I-10 “Split” interchange and Peoria Avenue, which is expected to be done by the end of October. 

The study determined a 65 mph speed limit within that stretch of I-17 is appropriate since it  more closely reflects the speed most people are currently driving and find reasonable. This is likely to improve compliance, providing an effective tool for law enforcement. 

The evaluation also notes a 65 mph speed limit can result in more drivers traveling closer to the same speed, which enhances safety.

The study ADOT commissioned followed passage of legislation (SB 1102) that calls for a minimum speed limit of 65 mph on any interstate highway in counties with a population of 3 million or more people. The law stipulates that a lower speed limit can be set if certain conditions are met, including:

• A lower limit is deemed necessary based on an independent engineering study or roadway assessment.
• The overall system capacity and mobility along the freeway will not be reduced.
• An opportunity for public input is provided.

The speed limit is at least 65 mph on all other stretches of interstate highways in the Phoenix area. Maricopa County is Arizona’s only county with a population topping 3 million.

Nearly 11,000 people submitted feedback to ADOT in a public survey. Approximately 75 percent of respondents supported raising the speed limit to 65 mph. 

Arizona law allows ADOT to establish speed limits on the state highway system "upon the basis of an engineering and traffic investigation.” The I-17 speed study evaluated a wide variety of factors including the average speeds that motorists are traveling, crash history, traffic volumes and the roadway design, to recommend an appropriate speed limit. 

To learn more about how ADOT establishes speed limits, please visit azdot.gov/SpeedLimits. 

PHOENIX – The Arizona Department of Transportation has launched a public survey to gather input about the speed limit along a stretch of Interstate 17 in Phoenix, in accordance with a new state law.

ADOT has commissioned an independent study to determine an appropriate speed limit for I-17 between the I-10 “Split” interchange near Phoenix Sky Harbor International Airport and Peoria Avenue. The speed limit for that part of I-17 is currently 55 mph. 

You can take part in the online survey from now through Saturday, Sept. 30, at https://tinyurl.com/I-17speedlimits; by email at [email protected]); and by phone at 1.855.712.8530. Comments also can be mailed to: I-17 Speed Limit Study, ADOT Community Relations, 1655 W. Jackson St., MD 126F, Phoenix, AZ 85007.

The speed study follows passage of legislation (SB 1102) that calls for a minimum speed limit of 65 mph on any interstate highway in counties with a population of 3 million or more people.

SB 1102 also stipulates that a lower speed limit can be set if certain conditions are met, including:

• A lower limit is deemed necessary based on an independent engineering study or roadway assessment.
• The overall system capacity and mobility along the freeway will not be reduced.
• An opportunity for public input is provided.

The I-17 speed limit study is scheduled for completion in mid-October.

PHOENIX – An Arizona Department of Transportation project that installed high-speed fiber-optic infrastructure along 67 miles of Interstate 17 between north Phoenix and McGuireville has won a regional award. 

The construction trade publication Engineering News-Record honored the team responsible for the project, including prime contractor Kiewit Infrastructure West Co., with a 2023 Best Projects Award of Merit for the Southwest region in the Specialty Construction category. 

As part of the state’s initiative to bring broadband internet access to more Arizonans, the $20.6 million project completed earlier this year installed conduit and fiber-optic cable between Anthem Way and the McGuireville Rest Area. This work connected and completed a broader project totalling 146 miles of fiber-optic conduit between Van Buren Street in Phoenix and the I-17/I-40 interchange in Flagstaff. Future fiber-optic conduit projects are planned along the length of I-40 through northern Arizona.

ADOT, which designed the winning project in partnership with Kimley-Horn, worked with Kiewit to use innovative micro-trenching technology to install the fiber-optic infrastructure under the asphalt shoulder of I-17. This helped address challenges posed by hard rock next to the highway and deliver the project in a safer, faster and more cost-effective manner with minimal impacts on the public.

Winning projects will be honored in Engineering News-Record’s Oct. 30 issue and at a luncheon in Phoenix on Oct. 31. 

Fiber-optic conduit also has been added along I-19 between the Tucson area and Nogales. These efforts complement a state law that allows private broadband providers to install, operate and maintain telecommunications equipment within ADOT’s right of way using conduit installed along state highways.

In addition to the benefits to rural broadband connectivity, ADOT plans to use the fiber to provide intelligent transportation systems technology, such as overhead message boards, traffic cameras, weather stations and wrong-way driving detection. The infrastructure also will help lay the groundwork for emerging technologies like connected and automated vehicles.

For more information on ADOT’s broadband efforts, please visit azdot.gov/Broadband.
See a map of current and planned fiber-optic conduit routes.

FLAGSTAFF – After a break due to the winter weather season, a project to repave and make other improvements along southbound Interstate 17 south of Flagstaff has resumed with lane restrictions starting today (Monday, April 24).

Drivers should expect lane restrictions in several areas while the pavement improvement work is underway over the next several months, according to the Arizona Department of Transportation.

Southbound I-17 is currently narrowed to one lane around the clock in several locations between Flagstaff and the Munds Park area during the current stage of repaving.

ADOT recommends drivers allow extra travel time, especially during peak travel times. Motorists also should obey reduced speed limits and stay alert for workers and equipment in all work zones.

In all, the $35 million project, which started last year, will repave 29 miles of southbound I-17 between Flagstaff and the Coconino/Yavapai county line. The project also includes bridge repairs and improvements along shoulders and interchange ramps. Work is scheduled for completion by fall 2023.

Real-time highway conditions are available on ADOT’s Arizona Traveler Information site at az511.gov. ADOT also provides highway condition updates via its Twitter feed, @ArizonaDOT.

PHOENIX – Drivers who travel Interstate 17 between Anthem Way and Sunset Point will undoubtedly notice a very different scene, as construction along this 23 miles of scenic highway is well underway.

Before the road is widened and the flex lanes are added, there is significant bridge work that must take place. The New River Road traffic interchange at milepost 232 has been under construction, as the bridges on both the northbound and southbound sides need to be widened from two lanes in each direction to three lanes. Massive girders were recently installed on both bridges in order to support the bridge decks, or the actual roadway, that vehicles will travel over once the project is complete.

The girders were set during the overnight hours, which is when most of the work is completed for the Arizona Department of Transportation’s I-17 Improvement Project. Crews from the Kiewit-Fann Joint Venture developer team set nine girders on each bridge during a two-night operation. There are three sizes of girders, or beams, with the largest weighing about 45,000 pounds (22.5 tons) and the smallest weighing about 30,000 pounds (15 tons).

Setting the girders is a critical operation for the construction crews and one that requires several hours of careful work. Getting the girders hoisted up and then set into place requires significant coordination, safety precautions and quality control. Girder placement signifies the start of completing the bridges at the New River Road traffic interchange, which is a major milestone.

The New River Road traffic interchange bridges are the first two of 10 bridges that will be widened as part of the I-17 Improvement Project. These two bridges are expected to be fully completed by late summer. Three additional bridges are being fully constructed or replaced as part of this project.

More about the I-17 Improvement Project:

Once complete in 2025, the I-17 Improvement Project will help alleviate congestion and improve safety and traffic flow north of the metro Phoenix region. The 23 miles of improvements include 15 miles of roadway widening from Anthem Way to Black Canyon City. One travel lane will be added in each direction along this stretch. In addition, an eight-mile flex lane system will be constructed from Black Canyon City to Sunset Point. Flex lanes are a new feature for Arizona’s highway system and are proven technology to help reduce congestion on I-17 during peak travel times and allow for traffic movement during emergency situations.

The I-17 flex lanes will operate as a separate, two-lane roadway carrying one direction of traffic at a time depending on the greatest need along the steep, winding eight miles between Black Canyon City and Sunset Point. For example, the flex lanes will be able to carry heavy northbound traffic on a Friday or heavy southbound traffic on a Sunday. Similarly, ADOT will be able to open the flex lanes to accommodate traffic any time if a crash or other incident causes long delays.

The two flex lanes will be next to, but physically separated from southbound I-17 using concrete barriers. Access to the flex-lane entrances will be controlled by gates. Overhead message signs will alert drivers to the open direction of the flex lanes. The flex lanes will be operational seven days a week.

For more information about the I-17 Improvement Project, visit improvingi17.com, call 877.476.1717 or email [email protected].

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