While debate rages over use of dredged spoils from waterbodies for NH construction in Kerala, the state government has enhanced the quantity of material that can be dredged from Vembanad lake. 

In April 2025, the Government had accorded sanction for dredging of spoil from Ashtamudi lake and Vembanad lake. The expected quantity of dredged material permitted for the Thuravoor Thekku – Paravoor Section of NH-66 is; Vembanad Lake: 5,50,000 Cu.M and  Andhakaranazhi Pozhi: 3,50,000 Cu.M. The total sanctioned quantity is 9,00,000 Cu.M.

In a meeting convened by the Additional Chief Secretary, Department of Water Resources, to discuss the ongoing NH development using dredged spoil,it was decided to cancel the permission for the removal of earth from Andhakaranazhi Pozhi location due to the presence of certain minerals.

The National Highways Authority of India (NHAI), has reported that the construction of highway approaches to underpasses and bridges is currently in active progress, for which dredged earth is required urgently. In order to compensate for the shortfall arising from the cancellation of dredging at Andhakaranazhi Pozhi and to meet the remaining project requirements, the NHAI requested permission to enhance the dredging volume from Vembanad lake up to 9,00,000 Cu.M, instead of the originally approved 5,50,000 Cu.M.

The Government has decided to grant permission to the NHAI to continue dredging from Vembanad lake up to a revised maximum limit of 9,00,000 Cu.M (Nine Lakh Cubic Meters) instead of 5,50,000 Cu.M, strictly to meet the balance material requirements of the ongoing project. 

A cave-in at 11th mile on the NH Alappuzha - Thuravoor stretch has reignited concerns over use of dredged materials from lakes for construction purpose. A massive crater was formed on the stretch, forcing authorities to suspend the traffic. While it has been temporarily concreted, residents and passengers are apprehensive. 

In March 2026, the High Court bench comprising Chief Justice Soumen Sen and Justice Syam Kumar dismissed a public interest litigation against use of dredged materials for the construction work of NH-66. The government, in its response, cited that Kerala Engineering Research Institute (KERI), the expert body, has scientifically examined the dredged materials and has certified that none of the raw materials conforms to any grading zones due to the presence of silt and clay content exceeding the specified limit. 

Non-mineral spoil, which is a mixture of silt, clay, and sand, not suitable for construction, found usable as a substitute for red earth in National Highway Development work, is being utilised subject to the compliance of standards and specifications for embankment filling, the government said in its affidavit.

According to the government, 25 soil samples had been collected from the parts of Vembanad lake that falls under the National Waterway which had been examined by KERI and reported that the dredged soil in question cannot be used for concrete works and most of the sand cannot be used for plastering and masonry works and can only be used for filling purposes.

 The order issued by the government also takes note of the report of the Director of Inland Navigation that since the spoil taken from the National Waterway, (NW3) in the Vembanad lake by dredging cannot be used for the construction works, the spoil can be given to the NHAI considering the fact that by utilising the said spoil for construction of National Highway, the national assets that would benefit the state could be created. 

 The Regional Officer of the NHAI had raised concern regarding the non-availability of red earth required for the development of alignment bases, levelling, and filling works in the stretches of national highways that were being undertaken. It was specifically pointed out that the shortage and limited availability of such red earth had been adversely affecting the progress of construction activities and could result in delays in the timely completion of the said work.

NHAI is expected to issue a press note on the matter soon.