Countdown to the Expiration of the US IIJA Act: The Critical Point of Federal Infrastructure Financing and the Anxiety of the Engineering Industry

Countdown to the "Cutoff" of Federal Infrastructure Funding

On September 30, 2026, the authorization period for the U.S. Infrastructure Investment and Jobs Act (IIJA) will officially end. This $1.2 trillion infrastructure bill, regarded by the industry as "epic," has been driving the U.S. public works market since its signing in 2021. Now, with the deadline approaching, anxiety is spreading across the sector.

Infrastructure as a "Stabilizer" Amid Weak Private Market

Over the past year, the U.S. private construction market has been generally weak except in data centers and energy, making public infrastructure projects one of the few stable growth points. Federal grants under the IIJA account for approximately 80% of funding for major U.S. transportation projects, which is crucial for the construction of roads, bridges, tunnels, and public transit systems. Jeffrey Shoaf, CEO of the Associated General Contractors of America (AGC), warned in a media briefing on July 2: "If Congress fails to pass a new funding bill in time, contractors will be forced to shelve projects, and construction jobs will be at risk."

Urgent Cases at the Project Level

Typical affected projects include the Gateway Development Commission's "Hudson Tunnel Project" (budgeted at $16 billion) between New York and New Jersey, and the Chicago Transit Authority's "Red and Purple Line Modernization Project" ($2.1 billion). Both projects recently won victories in court, with judges ruling that the Trump administration could not freeze funds already allocated under the IIJA. However, if the IIJA authorization expires, uncertainty over future new funds will directly impact subsequent financing arrangements.

Funding Won't Stop Immediately, but Uncertainty Has Arrived

While the expiration of the IIJA will not instantly cut off all funding flows—Anirban Basu, chief economist of the Associated General Contractors of America, noted that already-authorized funds will continue to be released into the early 2030s—new project launches will face challenges. Basu said: "The sectors supported by public finances are currently performing okay, but the private sector has few highlights besides data centers and energy. Maintaining infrastructure momentum requires new legislation."

An AGC poll shows that 78% of U.S. voters want Congress to pass a new transportation funding bill called "Build America 250." However, political gamesmanship could delay the bill. Shoaf commented: "Congress seems to always take the path of least resistance, but they cannot avoid such an important gear of economic growth."

Project Financing and Long-Term Risks

From a project financing perspective, the expiration of the IIJA may cause capital markets to adopt a wait-and-see attitude. Infrastructure investors often rely on federal commitments to reduce long-term risks; once the authorization is interrupted, the financial viability of public-private partnership (PPP) projects will be impacted. Especially for large-scale, long-cycle projects like railways and bridges, stable federal funding is a prerequisite for attracting private capital.

A Perspective on Global Infrastructure CompetitionThe United States is facing an infrastructure race with China, and the IIJA is seen as a cornerstone for responding to global competition. For example, the Gateway Tunnel project aims to increase rail capacity in the Northeast Corridor, directly impacting regional economic competitiveness. If federal infrastructure funding fluctuates due to political gridlock, it would amount to self-inflicted harm on competitiveness. In contrast, China is continuously exporting its infrastructure capabilities through the Belt and Road Initiative, while Europe is also accelerating the Trans-European Transport Network (TEN-T). The intermittent nature of U.S. infrastructure financing could undermine its ability to mobilize long-term engineering capital.

Industry Responses and Outlook

The Trump administration's wavering stance on infrastructure (including attempts to withhold Gateway project funding), along with partisan divisions in Congress, has clouded the prospects for renewing the IIJA. Contractor associations are actively lobbying, emphasizing the importance of infrastructure for employment and economic resilience. Lynn Hansen, CEO of Charlotte-based Crowder Constructors, stated bluntly: "If federal funding is reduced or fails to keep pace with growth and inflation, our projects will be delayed, and construction jobs will be threatened."

In the short term, the already approved IIJA funding pool will continue to support ongoing projects, but new projects face the risk of a funding cutoff. The industry expects that if no new legislation is passed by the end of September, infrastructure bidding in the fourth quarter will slow significantly. In the long run, the U.S. needs to establish a more stable annual infrastructure appropriation mechanism rather than relying on a once-every-five-years "megabill."

Conclusion: The expiration of the IIJA is not just an administrative deadline but a stress test of U.S. federal infrastructure governance capacity. Against the backdrop of structural weakness in the private construction market, the continuity of public infrastructure is directly tied to industry confidence and long-term national competitiveness. Whether Congress can pass "Build America 250" on time will determine the pace and direction of U.S. engineering capital flows over the next decade.