Summary

On 30 June 2026, the Federal Council published its report on traffic development on Swiss national roads. In 2025, 30 billion vehicle kilometers were driven on the network; congestion hours increased by 20 percent to 68,040 hours. The main cause is traffic overload (89 percent) rather than construction sites. Commuter routes such as the A1, A2, and A3 are particularly affected. The network no longer functions only at peak times, but operates near capacity limits almost throughout the day.

Persons

  • Federal Council (collective body; responsible for transport policy)

Topics

  • Traffic development on national roads
  • Congestion levels and traffic flow problems
  • Infrastructure expansion and traffic management
  • Automated driving

Clarus Lead

The overload of Swiss national roads is no longer a peak-hour problem, but a structural permanent problem. The 20 percent increase in congestion hours signals that intelligent traffic management systems and technological solutions alone are insufficient. The Federal Council derives from this the necessity of targeted network expansions – a politically sensitive signal in a country that increasingly questions infrastructure projects critically. The public consultation on the "Traffic '45" project, launched on 19 June 2026, will show whether cantons and municipalities are willing to accept targeted expansions.

Detailed Summary

The national road network bears a disproportionate load: With only 3 percent of the road network, it accounted for 45 percent of all vehicle kilometers in 2025. Freight transport is particularly dependent: Over 70 percent of heavy goods traffic uses national roads. Passenger cars drove approximately 25 billion kilometers (+1.5 percent compared to 2024).

Congestion problems are concentrated on commuter routes. The A1 (Geneva–St. Gallen), A2 (Basel–Chiasso), and A3 (Basel–Sargans) were particularly strained in 2025. A critical phenomenon: road users divert to cantonal and municipal roads when national roads become unreliable. On parallel cantonal roads, traffic growth is sometimes higher than on motorways – a sign of diversion traffic that additionally burdens local villages and agglomerations.

The ASTRA relies on operational optimization: Speed harmonization and temporary emergency lane activation have demonstrably reduced congestion on the A6 (Thun–Bern) and A1 (Winterthur). Since late 2025, the "Traffic Management Switzerland" application for centralized control has been in operation. In parallel, potential benefits of highly automated driving are being explored with the automotive industry. However, the report acknowledges: these measures are insufficient in the medium term. Systematic bottlenecks require targeted network expansions, which the DETEC has prioritized in the "Traffic '45" project.

Key Points

  • Structural Overload: Congestion hours increased by 20 percent in 2025; traffic overload (not construction sites) is the main cause
  • All-Day Congestion: Traffic is distributed throughout the day; the network is no longer overloaded only during peak hours
  • Diversion Traffic: Unreliability drives traffic to cantonal roads, placing additional burden on municipalities
  • Technology is Insufficient: Intelligent systems and automated driving alone cannot solve structural bottlenecks; expansions are necessary

Critical Questions

  1. Data Quality: Congestion hours are based on traffic reports from Viasuisse and manual collection. How robust is this methodology given the planned switch to automated collection (Floating Car Data)? Could transition phases compromise comparability?

  2. Causality of Diversion Traffic: The report observes higher growth on cantonal roads parallel to national roads. Is this definitively diversion traffic, or are there alternative explanations (e.g., regional population growth, changed settlement patterns)?

  3. Effectiveness of Measures: Emergency lane activation showed local success (A6, A1 Winterthur). How scalable is this model for other routes? What safety risks arise?

  4. Conflict of Interest in Expansion Projects: The DETEC prioritizes expansions in the "Traffic '45" project while simultaneously launching the public consultation. To what extent could the report serve as a legitimization tool for expansion plans that are politically controversial?

  5. Automated Driving – Time Horizon: The report names automated driving as a medium-term solution. What evidence supports the assumption that automation reduces congestion hours? Are there not also risks (increased mobility, induced demand)?

  6. Substitutes Not Investigated: Are modal shift potentials (rail, public transport) analyzed, or is the focus exclusively on road expansion?

Bibliography

Primary Source: Report "Traffic Development and Availability of National Roads 2025" – Federal Roads Office (ASTRA), 30.06.2026

Supplementary Sources:

  1. "Traffic '45" Project – DETEC
  2. Viasuisse – Traffic Information System (Data basis for congestion hours)

Verification Status: ✓ 30.06.2026

This text was created with the assistance of an AI model. Editorial Responsibility: clarus.news | Fact-Checking: 30.06.2026