A $3.5 billion new freeway for the West Valley, the $967 million last two-lane stretch of I-10, two border ports, a suspended $624 million light-rail extension, ASU's founding medical school — and, listed once for both states, Hoover Dam's $52 million turbine rescue — headline Arizona's public pipeline.
*How to read the total: the sum of the published figures in the list below. Bases differ by project — most are total cost estimates, some are federal grants, program totals, or construction contracts as awarded. Each project's expanded view labels its own basis. We add them up with the labels showing rather than pretend they're all the same kind of number.
Hover a pin for the project snapshot. Pin numbers match the project list below. Locations are approximate (nearest city or corridor midpoint) on a schematic state outline.
Click any project to expand its full record — description, owner, dates, funding, the law behind it, and its source. Filter by who owns it and where it stands, or sort by cost.
16 major public projects are listed. The listed figures sum to $8,419,616,965 (≈$8.42B) — and one record dominates it: ADOT's $3.5B SR 30 center segment, a funded-but-not-yet-building freeway carried at its published program total. Bases differ and are labelled on every record: program totals, published project totals, two awarded contracts (Douglas, Davis-Monthan) and one committed federal investment (Hoover Dam). This is a majors list, not a census: ADOT's five-year program, the universities' capital plans and city capital budgets carry hundreds of smaller projects below this page's $10M published-figure threshold.
The Hoover Dam record: Hoover Dam sits on the Arizona–Nevada line, and by agreement its current federal capital work is listed ONCE — here (az-015), at the Bureau of Reclamation's committed ≈$52M for wide-head turbine replacement and infrastructure work announced in 2026. Nevada's page carries a pointer to this page and no duplicate record. The allocation facts are printed on the record: of Hoover's firm energy, Arizona takes 18.9527% and Nevada 23.3706% (Reclamation), with most of the rest going to Southern California. Larger Hoover figures in circulation — ≈$156M to replace all 12 older turbines, $200M-plus of decade plant needs — are estimates of need, not committed work, and are disclosed on the record rather than counted.
Tribal-government projects — documented, excluded by the owner rule: Arizona's largest tribal-led infrastructure effort is not a public-owner build under this page's rules and is named here with its figures. The Northeastern Arizona Indian Water Rights Settlement (Navajo Nation, Hopi Tribe and San Juan Southern Paiute Tribe, signed July 17, 2024) would authorize $5.0B of federal funding — including a $1.715B Reclamation pipeline to be completed by 2040 and $3.285B of tribal trust funds ($2.746B Navajo, $509M Hopi, $30M San Juan Southern Paiute) — but as of October 2026 the authorizing bills (H.R. 8940 / S. 4633, 2024) had NOT been enacted, with the settlement reported stalled amid Upper Basin state opposition in mid-2026; it is therefore documented here, not listed. The Yavapai-Apache Nation Water Rights Settlement (2024 bills) is in the same unenacted position. By contrast, the Navajo-Gallup Water Supply Project IS a federal-owner build (Bureau of Reclamation; most recent estimate $2.2B, completion end-2029) — but it is a New Mexico-primary project (Gallup and the eastern Navajo Nation in New Mexico, with Arizona chapter connections around Fort Defiance and St. Michaels, including a ≈$9M chapter-connection design package approved by the Navajo Nation in May 2026), so it is accounted for on New Mexico's coordination rather than duplicated here. Separately, Interior announced $224M for Arizona implementation of already-enacted settlements for the Gila River Indian Community, San Carlos Apache Tribe, Tohono O'odham Nation and White Mountain Apache Tribe — settlement funding flowing to tribal governments, named here rather than listed as state/federal construction records. The Gila River Indian Community is also a funding partner (not owner) in the listed I-10 Wild Horse Pass project, whose corridor crosses Community land.
Deliberately excluded — private and third-party builds, however large: TSMC's semiconductor fabs and other private industrial construction in north Phoenix; all private data centers (their grid impact is measured on the What's Still Missing page); private utility generation and transmission (APS and SRP are investor-owned/public respectively — SRP appears only as co-owner of the listed SCIF water facility); the University of Arizona's ≈$250M, 19-story freshman residence hall at Speedway and Campbell in Tucson (site cleared May–June 2026, opening fall 2028) — a Collegiate Housing Foundation / Mortenson Development third-party build on a 50-year UA ground lease with no UA debt obligation, excluded under the owner rule and named here; and Pima County's Mosaic Quarter sports complex in Tucson ($425M of credit-tenant-lease financing, county as lessee, private developer) — a county-leased private development, named rather than listed.
Completed in a prior year, however large: Valley Metro's South Central Extension / Downtown Hub light rail ($1.34B, opened June 7, 2025) and Northwest Extension Phase II ($401.3M, opened January 27, 2024); ADOT's I-17 Anthem Way–Sunset Point improvement ($522M, flex lanes opened September 2025, substantial completion December 18, 2025), the I-10 Broadway Curve Improvement Project (completed 2025), the I-10 Ina–Ruthrauff predecessor phases' companion work, the U.S. 93 Tegner Street–Wickenburg Ranch Way widening ($55M, completed — final striping following ADOT's completion announcement), the Loop 202 South Mountain Freeway (opened 2019), and the University of Arizona's Applied Research Building (opened 2023) and ASU's University Gateway Building ($78M, completed January 2025). Two 2026 completions ARE listed under the current ruling — I-10 Ina–Ruthrauff (spring 2026) and Kingman's Flying Fortress Parkway interchange (October 2026) — and the Capitol Extension is carried as suspended on the verified January 2026 council vote and Valley Metro's suspension announcement.
Unfunded or unpriced planning, named not listed: ADOT's North–South Corridor (SR 505, Apache Junction to Eloy) — the 55-mile corridor was selected in 2021 and Tier 2 environmental studies for Segment 1 (US 60 to Arizona Farms Road) and Segment 2 (to I-10) run through 2027–2028, but no construction cost or funding has been published, so it fails this page's published-figure rule and is named here only; the eastern and western segments of SR 30 beyond the funded center segment; Phoenix Sky Harbor's long-range terminal planning beyond the funded Terminal 3 North 2 concourse and Taxiway Uniform; and Luke Air Force Base work, for which no current priced project record could be verified (Davis-Monthan carries this page's Air Force record).