The orange barrels and dark new asphalt on State Route 347 are real progress. They are not the widening Maricopa drivers have been waiting to use.
The work now moving south toward the city is Phase 1: pavement rehabilitation. ADOT’s project page says that phase runs through December 2026. It renews the existing pavement and shoulders along the 14-mile corridor between Interstate 10 and Maricopa.
The extra lane in each direction, concrete median, two new interchanges and intersection changes belong to later phases. ADOT says the full project remains targeted for completion in late 2029.
Understanding that distinction makes the current construction easier to read: a smoother surface can open while the corridor still has the same basic capacity and signals it had before.
What drivers are seeing now
ADOT’s active Oct. 22–30 notice calls for northbound overnight lane reductions from Maricopa to Casa Blanca Road through Friday morning, Oct. 30. It also flags more overnight work for the weekend beginning Oct. 30, with details still to be finalized at the morning cutoff.
The agency says two lanes will remain open in each direction during weekday commute hours. Most restrictions are scheduled overnight or on weekends. The corridor-wide speed limit is 55 mph, dropping to 45 mph in active work zones.
For day-to-day planning, use the OurMaricopa SR 347 commuter guide alongside ADOT’s live page and AZ511. A project overview cannot replace a same-day lane or incident alert.
What comes after repaving
ADOT’s planned construction package includes:
one additional travel lane in each direction from I-10 to Maricopa;
a concrete median barrier separating opposing traffic;
grade-separated interchanges at Riggs Road and Mammoth Way;
added turn lanes and other intersection work at Casa Blanca Road and Maricopa Road; and
signal and lighting improvements at selected intersections.
At Riggs Road, ADOT says SR 347 will pass over the east-west road. Riggs will remain at ground level with two through lanes in each direction plus turn lanes connecting to the highway.
Mammoth Way—not Casa Blanca Road—is planned for the other interchange. ADOT’s FAQ says Casa Blanca’s proximity to the Santa Cruz Wash would require more complex engineering and two additional bridges, and an interchange there was estimated to cost $40 million more. Casa Blanca is instead slated for dual left-turn lanes onto southbound SR 347, a northbound acceleration lane, a southbound right-turn lane, signal changes and lighting.
“Winter” is a window, not a start date
ADOT’s FAQ says future phases, including widening, interchange construction and intersection improvements, will begin in winter 2026. The main project page says detailed phasing will be published before the end of the year, and its schedule graphic places the future work across 2027 through 2029.
Those statements establish a transition period, not a single confirmed groundbreaking day for every component. “Winter 2026” can describe preparatory or initial work while the widening, bridges and intersections follow different construction schedules.
The Riggs interchange illustrates why. ADOT says environmental clearance and right-of-way work were still being secured before that construction could be scheduled. Once interchange construction starts, the agency estimates roughly one year to build it. ADOT also says the bridge will be constructed east of the existing road so traffic can continue and the project does not require an extended full closure of Riggs Road.
Until the detailed phasing update arrives, residents should be cautious with claims that an interchange, added lane or median is “under construction” merely because paving equipment is visible nearby.
What the project is supposed to deliver
ADOT says its 2021 corridor plan projected about a 10-minute reduction in full-corridor travel time after the planned improvements are complete. That is a planning projection, not a promise for every commute or a benefit produced by the repaving phase alone.
Maricopa’s own funding role is substantial. OurMaricopa’s half-cent road-tax breakdown explains the City’s $50 million contribution and the fund balance reported in City records.
The next meaningful milestone is not another stretch of black pavement. It is ADOT’s detailed phasing release: which future component starts first, where traffic shifts, how long each segment lasts and when drivers can expect new capacity—not just a new driving surface.
Sources
Arizona Department of Transportation — SR 347 Improvement Project. https://azdot.gov/projects/central-district-projects/sr-347-improvement-project. Current alert and project overview accessed Oct. 28, 2026. Source for current restrictions, Phase 1, planned improvements, traffic-management commitments and late-2029 target.
Arizona Department of Transportation — Frequently Asked Questions, SR 347 Improvement Project. https://azdot.gov/projects/central-district-projects/sr-347-improvement-project/frequently-asked-questions. Based on the June 17, 2026 open-house Q&A; accessed Oct. 28, 2026. Source for phase transition language, interchange concepts, Casa Blanca design, projected travel-time change and unresolved Riggs scheduling.