4 days ago
Early returns favorable as massive I-10 rebuild ends
You sat in more stop-than-go traffic on Interstate-10 on the way home from work while you resisted the urge – or not – to hurl epithets.
That's the way it was.
The way it is now, as Arizona Department of Transportation mops up its nearly four-year rebuild of the Valley's busiest freeway, 11 miles from I-17 through the Broadway Curve to the Loop 202 interchange in Ahwatukee: Better. It's fresh, so it's going to take time to assess how much better.
ADOT has finished the heavy lifting. The new traffic lanes, interchanges and bridges are done. What remains is landscaping, lane striping, signage, lighting and completion of ramps that lead to two new pedestrian/cyclists bridges over I-10, which ADOT hopes to complete by June 1.
It is the largest rebuild of a freeway in ADOT history.
'We are just so happy that all of the major components of the project are done, the big stuff, and we are now just focusing really on the cosmetics part of the project,' said Marcy McMacken, ADOT spokeswoman. 'We are over the moon about it, with how well this project has gone.
'We've already gotten a lot of positive feedback, so we're glad to hear that the difference is very noticeable from four years ago.'
Finally, relief
For drivers, who for years endured not only weekday jams of traffic at rush hour on an outdated freeway but then also closures and restrictions on weekends during construction, the misery is over.
When Interstate 10 was built through the Broadway Curve in the mid-1960s, the Valley had a population of about 800,000. Today, it is 5 million. ADOT estimates that 300,000 vehicles use the stretch of freeway every day. In the coming 15 years, ADOT estimates the number will rise to 375,000 a day.
The average speed on eastbound I-10 from I-17 to U.S. 60 during afternoon rush hour before the rebuilding project was 32 mph, ADOT said. Without the project, that speed was projected to decrease to 29 mph by this summer and trend downward over time.
With the I-10/Broadway Road Improvement project completed, average speed is projected to increase to 40 mph this summer.
According to a Maricopa Association of Governments economic evaluation in 2020, improvements from the project will save motorists 2.5 million hours annually that otherwise would have been spent in traffic – totaling $130 million a year in time savings due to quicker commutes.
There's good news for ADOT, too, according to McMacken.
'We are expected to be under budget,' she said.
ADOT had paid out $646,637,489 through early May, according to McMacken. The figure will rise slightly when work is completed and contractors receive their final checks in June.
What's new?
With the addition of main traffic lanes, high-occupancy vehicle lanes and collector distributor roads for local traffic, capacity on I-10 has increased by 60 percent through the Broadway Curve.
What taxpayers got for their money:
I-10 widened to six general-purpose lanes and two high-occupancy vehicle lanes in each direction from U.S. 60/Superstition Freeway west to Interstate 17.
I-10 widened to four general-purpose lanes in each direction from Ray Road north to U.S. 60.
New, wider bridges over the freeway at Broadway Road and 48th Street.
Wider bridge over the Salt River.
Roadway improvement on approximately one mile in both directions of U.S. 60/Superstition Freeway from I-10 to Hardy Drive.
Roadway improvement on approximately one mile in both directions of State Route 143/Hohokam Expressway from I-10 to the southern end of the SR 143 bridge over the Salt River.
Addition of collector distributor roads next to I-10 from Baseline Road west to 40th Street to separate through-traffic on the freeway from local traffic entering or exiting at Broadway, SR 143 to Phoenix Sky Harbor International Airport and 48th Street.
Complete rebuild of I-10/SR 143 interchange with direct connections to and from SR 143 via flyover bridges to I-10.
Two bridges for pedestrians and bicyclists over I-10 at Alameda Drive and the Western Canal, and improving the Sun Circle Trail crossing at Guadalupe Road.
Sound and retaining walls where warranted.
An LA twist
The collector distributor roads are the most unique element of the project that get exiting and entering traffic off the main through lanes via what amounts to a parallel mini freeway for local traffic.
There used to be a mad scramble where traffic off westbound I-10 heading for Broadway Road or SR 143 to the airport had to cross several lanes of traffic to the right in less than a mile while traffic entering I-10 west from U.S. 60 was crisscrossing as those drivers were moving left to get onto the I-10 through lanes.
Collector distributors relieve most of the stress with dedicated lanes. Reducing the need for lane changes enhances safety, according to McMacken.
There was a learning curve for motorists, though.
'The feedback on them has been amazing,' McMacken said. 'In the beginning, it was a new concept for many drivers, because we've never had that in the Phoenix area. Our educational campaign was launched over a year ago, letting the drivers know what these roads were and how to use them.
'Nobody around here had seen it unless they'd been to LA, or places like that. And I think it did take people a while to figure it out. The first couple of times through, even for me, and I've been to LA a lot, there was that learning curve because it was just so different. Now, they are being used as they should be, and it's made a difference.'
The project was funded largely by revenue from a half-cent transportation sales tax, Proposition 400, that voters countywide approved in 2004. MAG, the regional transportation planner, identified the need to reduce travel times on I-10 during peak hours, improve airport access, support ridesharing and transit with more HOV lanes, and to prepare the region for future growth projections.
'At the beginning of the project, one of the requirements of the construction crew was that they do not conduct any full-freeway closures during the work week, during peak travel times,' McMacken said. 'They stuck to that. They did not conduct any freeway closures Monday through Friday.
'We are pleased that we were able to stick to that to minimize the impact on motorists. If we would have closed it during weekdays, the project would have been completed a while ago, but we knew that wasn't possible just because of where this project was located with its heavy volume of traffic.'
What's ahead
Crews will continue some landscaping work over the coming year, McMacken said.
And then, ADOT's focus shifts south, to the 26-mile Wildhorse Pass Corridor along I-10 from Loop 202 to just north of Casa Grande, the final segment of the freeway that is only two lanes in each direction between Phoenix and Tucson.
A separate project already is underway at the I-10 Gila River crossing, where bridges are being rebuilt and widened.
The first of four phases of the Wildhorse Pass Corridor project is Loop 202 to Riggs Road. McMacken said ADOT expects to begin widening that stretch in late summer of 2026.
