Explainer: Why Coimbatore & Madurai Didn’t Get Metro Rail Approval? What Went Wrong For Tamil Nadu?

The Union Ministry of Housing and Urban Affairs has turned down Tamil Nadu's proposals to build metro rail networks in Coimbatore and Madurai, triggering a political and public backlash in the state.

The rejection is rooted in the strict application of the National Metro Rail Policy, 2017, which sets population and ridership benchmarks for approving such high-cost projects. But the decision also rekindles a recurring national debate: Why do some smaller cities in India get Metro projects while others are denied on technical grounds?

What the Centre Found in Tamil Nadu's Metro Plans

Tamil Nadu submitted detailed project reports (DPRs) for both Coimbatore and Madurai, seeking a 50:50 funding partnership with the Union government. After a "careful and thorough" appraisal, the Centre rejected both proposals on November 14, according to a report in The New Indian Express.

According to the ministry's letter, the DPRs overestimated ridership, underestimated engineering challenges, and failed to meet mandatory eligibility conditions-particularly the minimum population requirement.

Coimbatore: Unrealistic Demand Projections and Structural Limits

For Coimbatore, the DPR projected 5.9 lakh daily passengers for a proposed 34-km network. The Centre found this implausibly high-even exceeding the nearly 4 lakh daily ridership recorded by Chennai Metro's 55-km Phase I in early 2025.

The report notes that the city's travel patterns do not justify such projections:

• Average trip lengths are only 6-8 km, limiting the time-saving edge required for commuters to shift from road to metro.
• Road travel speeds are already comparable to the speeds expected from the metro system.
• Many stretches along the proposed alignment run through roads only 7-12 metres wide, making elevated stations technically challenging without significant demolition.

The appraisal also highlights the DPR for assuming an unrealistic three-year construction period and deviating from economic-return guidelines.

Most importantly, Coimbatore's 2011 municipal population of 15.84 lakh does not meet the 2 million (20 lakh) threshold set by the 2017 policy. Although the larger planning area is much bigger, the Centre noted that these outer regions are not covered by the proposed metro corridors and therefore cannot be counted as ridership generators.

Madurai: More Suitable for Bus Rapid Transit, Says Centre

Madurai faced the same population issue, but the ministry also pointed to the city's own Comprehensive Mobility Plan, which had recommended a Bus Rapid Transit System (BRTS) over a metro. The Centre argued that strengthening the existing bus network or building a BRTS would deliver better value at far lower cost.

In both cases, the letter emphasised that metro systems are cost-intensive, long-term investments that must be justified through demographic, engineering, and financial viability.

Why, Then, Do Smaller Cities Elsewhere Have Metros?

This is where the controversy intensifies. Tamil Nadu leaders and citizens point out that cities such as Gurugram, Bhubaneswar, Agra, Patna, and Bhopal obtained metro approval despite having less than 20 lakh population in the 2011 Census.

Technically, the 2017 policy's population criterion is still in force. But several exceptions have been made based on:

• State and political lobbying
• Urban agglomeration (UA) size exceeding municipal limits
• Projected population growth
• Tourism importance, e.g., Agra
• Integration with larger regional transit networks, e.g., Gurugram-Delhi connectivity

The Centre has never formally listed the reasons behind these exceptions, creating space for political interpretations.

Tamil Nadu CM Slams Centre

The decision has predictably escalated into a political flashpoint. Chief Minister MK Stalin accused the Centre of political bias, alleging that BJP-ruled states receive metro approvals for smaller tier-II cities while opposition-ruled states do not. He linked the rejection to what he called an attempt to "take revenge" on Tamil Nadu for its democratic choices.

Local activists and urban groups in both cities expressed shock and disappointment, noting that citizens have been demanding metro connectivity for over 15 years.

The Larger Debate

At its core, the controversy highlights the tension between strict policy adherence and flexible, case-based exceptions.

Metro projects are capital-intensive and not always justified for mid-sized cities. Yet the irregular application of rules across states raises questions about transparency and political influence.