Kerala Water Authority has proposed a Rs 45 crore tertiary sewage recycling project at Muttathara in Thiruvananthapuram to supply treated wastewater to major commercial and industrial users, potentially reducing their dependence on freshwater during periods of high demand.
The project will include a 15 million-litre-a-day tertiary treatment plant and a pipeline network spanning around 10km. The airport, Railways, Titanium, Veli Industrial Estate and Technopark have been identified as prospective consumers of the recycled water, according to a Kerala Water Authority engineer quoted by the Times of India.
The proposed facility will further treat partially treated sewage effluent generated by the existing 107 MLD sewage treatment plant at Muttathara. The existing plant currently produces around 60 MLD of partially treated effluent, but the new facility will initially process only 15 MLD rather than the entire volume available.
Tertiary treatment is intended to improve the quality of the effluent so that it can be used for non-drinking purposes, subject to prescribed quality standards. The recycled water could be used by commercial and industrial establishments for part of their requirements, allowing them to rely less on conventional freshwater supplies.
The Kerala Water Authority initially considered transporting the treated water to users through tankers. During discussions, prospective consumers sought direct pipeline connections instead. The authority subsequently included the 10km distribution network in the project proposal. The prospective consumers have agreed to purchase the recycled water provided the authority ensures supply through pipelines, the engineer said.
The tariff for the treated water has not yet been finalised. Supply agreements with the prospective buyers are also pending. The actual quantity supplied to each establishment will depend on the final arrangements and the availability of treated water from the proposed facility.
The project comes as the authority faces increasing water demand from economic activity, industries, services and shopping centres in the city. A KWA engineer said the authority often struggles to meet demand during peak summer with the available supply. Reusing treated sewage for non-potable requirements could leave more freshwater available for households and other consumers during such periods.
The administrative sanction for the project has been completed and the tendering process is under way. Construction is expected to begin after the tender is finalised, while the project schedule provides 12 months for construction. The finalisation of consumer agreements and the tariff structure remains the next significant step before supply arrangements can be established.
