The “Michigan left” part of the Oracle-Grant intersection was almost complete in 2013, and more work on Grant, to the east, is about to begin.

Kelly Presnell / Arizona Daily Star 2013

About 3½ years after Phase 1 of the Grant Road Improvement Project was finished, Phase 2 is just weeks away from getting underway.

The Road Runner got a hold of the preliminary construction schedule to help readers plan for the substantial remaking of the major east-west arterial between North Stone and Park avenues.

Once complete in 2023 — according to current estimates — the massive six-phase project will provide six lanes of travel, as well as bike lanes and pedestrian safety features, from North Oracle to Swan roads at a cost of about $100 million in 2008 dollars. The engineering estimate for Phase 2 was a little over $17 million, but Phoenix contractor Markham won with a bid of $14.5 million, the money for which will come from the sales-tax-funded Regional Transportation Authority.

Before we dive into the details, an important qualifying note: All of the dates you’re about to read are tentative, meaning they are subject to change and vulnerable to the vagaries of Southern Arizona’s often extreme weather, among other factors.

“It’s the best-case scenario,” David Burbank, the Tucson transportation department’s Phase 2 project manager, said of the preliminary schedule, before graciously walking the Road Runner through each of the project’s six stages — many of which run concurrently with other stages — and how they will likely impact the motoring public.

Construction is slated to start March 20, when Markham gets the first stage going, which includes building a retention basin, clearing vegetation along the work area, utility research and laying the new eastbound lane. These elements of the project will have little impact on traffic flow and will last through June 2018, according to Burbank.

“Traffic’s going to flow as if no one’s there,” he said.

Construction was originally expected to start in 2015, but delays with utility companies moving their communication lines held that up, according to city engineer Fred Felix.

The second stage will kick off May 22, and will involve substantial work to Stone Avenue north and south within a block or two of its intersection with Grant.

Markham will build new sidewalks and access points, among other things. Unlike stage one, the work on Stone, which is expected to last until early August, will come with some lane restrictions.

The following stage, expected to stretch from June 8 to Aug. 18, will be more or less the same as the Stone work, but at First and Euclid avenues, further east.

The fourth stage will deal with westbound Grant, and last from late August through mid-December. Initially, there will be a fair amount of utilities work, and toward the end crews will build the new third lane.

“This will impact travel, where we’re temporarily putting it down to one lane, using the new eastbound Grant Road and moving traffic onto that,” Burbank said.

The fifth stage will also have significant traffic impacts as Markham builds the raised median in the middle of Grant from mid-November through early January 2018. To accommodate that work, the lane closest to the median for both directions will be closed, though there will still be two lanes of travel open through much of the project area.

And finally, from late November through early March 2018, Markham will finish off work on westbound grant from Stone west to Castro Avenue. Through all the phases, Burbank said business access would be maintained.

“It won’t be as painful as everybody thinks,” Burbank said, adding later: “Be patient with us, we will deliver a roadway that’s going to be very usable, it’s going to improve traffic movement, it’s going to improve safety, and it’s going to look modern by the time were done with it.”

In addition to the features described above, when all is said and done Grant will have two new indirect left turns, which are also known as Michigan lefts, at Stone and First, in addition to the one that is already at Grant’s intersection with Oracle.

When Tucson drivers first got a taste of the novel intersections, which are intended to improve traffic flow and safety, many took a dim view of them. However, while 80 percent of respondents to a 2013 Star poll said they disliked the traffic innovation, that number fell to 50 in a similar poll conducted last year.

To keep an eye on how they function in the real world, the RTA’s Jim DeGrood said baseline data on the intersections was recently collected to compare it to the intersections after the indirect lefts are constructed. When the data is available, the Road Runner will certainly give it a look.

To promote economic development after Phase 2 is complete, city officials are contemplating what is known as an Urban Overlay District, which allows a degree of regulatory flexibility when it comes to certain zoning requirements. For example, Rebecca Ruopp, who is overseeing land-use planning for Phase 2, said that parking-space requirements could be loosened in exchange for additional landscaping work at a business.

For some of the parcels the city acquired leading up to Phase 2, it is considering soliciting requests for proposals for that land. If you’re interested in this side of the project, there will be a public meeting on March 2 at 5:30 pm at the Donna Liggins Recreation Center, 2160 N. Sixth Ave.

DOWN THE ROAD

It’s not coming next week, but county residents near Colossal Cave Road should mark their calendars with the following dates.

Between March 13 and March 26, there will two separate closures of the road’s railroad crossings with more or less the same traffic impacts.

On March 13-14, the crossing at the northbound tracks will be closed, and from March 15 through March 26, the closure will be at the southbound tracks.

In both cases, motorists trying to get to Colossal Cave Road north of the tracks from Interstate 10 will have to take the Houghton Road exit (275), travel north to Mary Ann Cleveland Way and head east to Colossal Cave. The business center just south of the tracks on Colossal Cave will be the last point of access.

Access to both Acacia Elementary School and Old Vail Middle School will be maintained.

Contact: mwoodhouse@tucson.com or 573-4235. On Twitter: @murphywoodhouse