Soaring Costs: These 25 Public Infrastructure Projects Are Way Over Budget

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In an oversight hearing last week, Congressman Kevin Kiley called on FBI Director Kash Patel to formally investigate the project overrun costs of the California High-Speed Rail. According to Kiley, the cost of the high speed rail project has ballooned by more than $100 million over its original budget, becoming the costliest public infrastructure failure in the United States.

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In the United States, at least a dozen public infrastructure projects have gone more than $1 billion over their original budgets in the last 25 years. Whether due to mismanagement, unrealistic cost estimates, expansions in scope, or delays in construction, these projects reflect the recurring challenges of bringing large-scale public works to completion on time and within budget, and are an impediment to transit infrastructure that can ease congestion and reduce harmful emissions. A look at the biggest project overruns of the last 25 years reveals the major public infrastructure failures of this century.

To determine the costliest public infrastructure overruns of the last 25 years, Climate Crisis 247 reviewed audits, budget reports, and press accounts of U.S. infrastructure projects from the Department of Transportation and other sources. Public work projects with clear, documented early cost estimates and later, final cost estimates were ranked based on the difference between first and last cost estimate. Early estimates are mostly based on federal Full Funding Grant Agreements, state ballot measures, and environmental review documents, while final costs are based on close-out audits for completed projects or the latest official estimates for those still underway. In instances where cost estimate ranges were provided, the higher estimates were used.

25. St. Louis Loop Trolley

• Estimated project overrun: $26.0 million
• Initial project cost: $25.0 million (2010)
• Final project cost: $51.0 million (2018)
• Project details: 2.2-mile streetcar line in University City/Delmar Loop

 

24. Chicago Riverwalk Expansion

• Estimated project overrun: $60.0 million
• Initial project cost: $50.0 million (2012)
• Final project cost: $110.0 million (2016)
• Project details: Pedestrian riverfront project through downtown Chicago

 

23. Port of Miami Tunnel

• Estimated project overrun: $61.0 million
• Initial project cost: $607.0 million (2007)
• Final project cost: $668.0 million (2014)
• Project details: Twin highway tunnels linking Port of Miami to I-395

 

22. Austin Waller Creek Tunnel

• Estimated project overrun: $145.0 million
• Initial project cost: $25.0 million (1998)
• Final project cost: $170.0 million (2017)
• Project details: Urban flood-control tunnel under downtown Austin

 

21. Seattle SR-99 Bertha Tunnel

• Estimated project overrun: $200.0 million
• Initial project cost: $3.1 billion (2009)
• Final project cost: $3.3 billion (2019)
• Project details: Highway tunnel replacement for Alaskan Way Viaduct

 

20. Washington Metro Silver Line Phase 2

• Estimated project overrun: $270.0 million
• Initial project cost: $2.8 billion (2012)
• Final project cost: $3.1 billion (2022)
• Project details: 11.4-mile extension to Dulles Airport and Loudoun County

 

19. San Francisco Central Subway

• Estimated project overrun: $372.0 million
• Initial project cost: $1.6 billion (2013)
• Final project cost: $2.0 billion (2022)
• Project details: 1.7-mile subway connecting SoMa to Chinatown

 

18. Bayonne Bridge "Raise the Roadway" Project

• Estimated project overrun: $400.0 million
• Initial project cost: $1.3 billion (2010)
• Final project cost: $1.7 billion (2017)
• Project details: Raised bridge clearance for larger Panamax ships

 

17. Los Angeles Metro Regional Connector

• Estimated project overrun: $430.0 million
• Initial project cost: $1.4 billion (2012)
• Final project cost: $1.8 billion (2023)
• Project details: 1.9-mile downtown LA light rail subway connector

 

16. Transbay Transit Center (Phase 1)

• Estimated project overrun: $660.0 million
• Initial project cost: $1.6 billion (2010)
• Final project cost: $2.3 billion (2018)
• Project details: Multimodal bus/rail transit hub in downtown SF

 

15. New Jersey Hudson-Bergen Light Rail Extension

• Estimated project overrun: $700.0 million
• Initial project cost: $1.2 billion (2009)
• Final project cost: $1.9 billion (2019)
• Project details: Light rail extension south into Bayonne

 

14. New York Second Avenue Subway (Phase 1)

• Estimated project overrun: $800.0 million
• Initial project cost: $3.8 billion (2007)
• Final project cost: $4.6 billion (2017)
• Project details: 2-mile subway under Manhattan’s East Side

 

13. Federal Way Link Extension

• Estimated project overrun: $996.0 million
• Initial project cost: $2.2 billion (2017)
• Final project cost: $3.2 billion (2019)
• Project details: 7.8-mile Link light rail extension to Federal Way

 

12. Minneapolis Southwest LRT (Green Line Extension)

• Estimated project overrun: $1.5 billion
• Initial project cost: $1.3 billion (2011)
• Final project cost: $2.8 billion (2025)
• Project details: 14.5-mile LRT from Minneapolis to Eden Prairie

 

11. BART Transbay Core Capacity Program

• Estimated project overrun: $2.0 billion
• Initial project cost: $2.4 billion (2017)
• Final project cost: $4.4 billion (2023)
• Project details: Capacity upgrades for BART Transbay corridor

 

10. The Portal Caltrain Downtown Extension (DTX)

• Estimated project overrun: $2.3 billion
• Initial project cost: $6.0 billion (2018)
• Final project cost: $8.3 billion (2023)
• Project details: 1.3-mile rail link into Salesforce Transit Center

 

9. Denver International Airport Baggage System

• Estimated project overrun: $2.8 billion
• Initial project cost: $2.0 billion (1989)
• Final project cost: $4.8 billion (1995)
• Project details: Failed automated baggage handling system

 

8. Maryland Purple Line (Light Rail)

• Estimated project overrun: $3.9 billion
• Initial project cost: $5.6 billion (2016)
• Final project cost: $9.5 billion (2024)
• Project details: 16-mile light rail linking Bethesda to New Carrollton

 

7. Austin Project Connect (Initial Light Rail)

• Estimated project overrun: $4.5 billion
• Initial project cost: $5.8 billion (2020)
• Final project cost: $10.3 billion (2025)
• Project details: Scaled-back 9.8-mile light rail starter line

 

6. San Francisco-Oakland Bay Bridge Eastern Span

• Estimated project overrun: $5.4 billion
• Initial project cost: $1.1 billion (1997)
• Final project cost: $6.5 billion (2013)
• Project details: Replacement of eastern span after earthquake damage

 

5. BART Silicon Valley Phase II

• Estimated project overrun: $5.8 billion
• Initial project cost: $6.9 billion (2018)
• Final project cost: $12.7 billion (2025)
• Project details: 6-mile BART subway/extension through San Jose

 

4. Honolulu Skyline Rail

• Estimated project overrun: $7.3 billion
• Initial project cost: $5.1 billion (2012)
• Final project cost: $12.4 billion (2023)
• Project details: Elevated rapid transit line in Honolulu

 

3. New York East Side Access

• Estimated project overrun: $8.1 billion
• Initial project cost: $3.5 billion (2000)
• Final project cost: $11.6 billion (2023)
• Project details: Rail connection bringing LIRR into Grand Central

 

2. Boston Big Dig

• Estimated project overrun: $19.2 billion
• Initial project cost: $2.8 billion (1985)
• Final project cost: $22.0 billion (2007)
• Project details: Central artery/tunnel highway megaproject in Boston

 

1. California High-Speed Rail

• Estimated project overrun: $95.0 billion
• Initial project cost: $33.0 billion (2008)
• Final project cost: $128.0 billion (2025)
• Project details: Planned high-speed rail line San Francisco to LA