From collapsed bridges and landslips to eroded service roads and waterlogged stretches, the construction of National Highway 66 across Kerala raises serious safety and environmental concerns. While touted as a key infrastructure upgrade, the project is marred by alarming incidents and expert warnings about unscientific soil excavation, poorly planned hillside cuts, and inadequate drainage. A district-wise look reveals a troubling pattern of structural failures and hazards that threaten both lives and livelihoods. 

1. Kasaragod
 84 km of National Highway in three stretches

Incidents:

• On May 12, an earth collapse at Cheruvathur killed a migrant worker during the construction of a concrete wall on a hillside.
• In Kanhangad, between Mavunkal and Chemmattamvayal, flash floods eroded the service road. A major crack about 20 metres long was found in the same area.
• In 2022, a bridge under construction in Periya collapsed.
• A study report flagged unscientific soil extraction from hills in Bevincha, Thekkil, Veeramalakunnu, and Mattalayi for highway construction. It also warned of landslide threats.
• The Thekkil curve on the Cherkkala-Chattanchal route has over 10 hairpin bends. A massive hill was split for road works, and levelled over a 2-km stretch.

2. Kannur
  Soil was excavated from a field between Empet and Pariyaram Government HSS for 100 metres. Hills were sliced for road construction from Kuppam to Chudala (2.5 km), and from Aattadappa to Muttolampara (3 km).

Incidents:

• On Thursday, a large concrete interlock structure collapsed from the elevated road at Chala onto the state highway.
• At Kapannathattu in Pariyaram, a crater formed on the service road. A tanker truck’s tyre sank in. On the Pilathara stretch, a retaining wall collapsed onto the service road.
• At CH Nagar on the Thaliparamba-Kuppam-Ezhom Road, landslide fears emerged after soil began slipping over a recently raised section.
• At Kuppam, nearly 100 residents sat in the rain, halting traffic demanding immediate action to stop sluch flooding their houses 

3. Kozhikode
 Construction split into two reaches, totalling 69.2 km: Ramanattukara-Vengalam Reach: 28.4 km, Vengalam-Azhiyur Reach: 40.8 km

Incidents:

• Waterlogging in low-lying areas remains the key issue between Ramanattukara and Vengalam, where 60% of construction is complete.
• Frequent landslips occur north of the Vadakara-Moorad bridge. No solution yet.
• At Kunnuoramala, a hill was split and houses on either side of the road are at risk of collapse. Nineteen families have been relocated.

4. Malappuram

Total highway stretch from Idimuzhikkal to Kappirikkad: 75.6 km, of which 93% is complete.

The state's largest viaduct is in Malappuram. Built from Unniyal bridge to Vattappara hill, it bypasses the accident-prone Vattappara curve. Length: 4.5 km.

A bypass from Palachiramad to Swagathamad avoiding Chankuvetti and Edarikode junctions runs 4.6 km, about half of which is elevated.

In the Calicut University area, over 3 km of hillside was excavated. In Mele Chelari, the cut is 10 metres deep.

Incidents:

• Over 200 metres of the Kooriyad highway and service road have sunk into a paddy field where over 12 metres of soil had been heaped up.
• In Kakkad, where a hillside was cut, service road soil collapsed twice last year, disrupting traffic.
• No drainage exists; even light rain causes waterlogging and floods nearby houses.

5. Thrissur 

Two reaches totalling 61.89 km: Kaparikkad–Thalikulam Six-Lane: 33.16 km, Thalikulam–Kodungallur Six-Lane: 28.73 km

The only viaduct in Thrissur district is in the Thalikulam–Kodungallur reach at Mathilakam (Mathilakam Bypass).

Total bypass length: 4.78 km

Viaduct length: 1.7 km 

Incidents:

• A crack over 25 metres long was found on the flyover under construction in front of Manathala Vishwanatha Temple, Chavakkad. Temporarily patched with tar.
• Retarring was done over a half-kilometre stretch. The flyover has not yet been opened.

6. Kollam

• Three accidents have occurred in the last six months during national highway construction in Kollam.
• On Tuesday, a landslip occurred during construction near the Chavara bridge.