Rehabilitation of Kolkata's first Victorian-age brick sewer

As early as 1868, the first man-entry brick sewer of Kolkata (then Calcutta) along Lenin Sarani (then Dharamtolla Street) was commissioned as a part of an organised effort to provide a comprehensive combined sanitation facility. Subsequently, the city saw its golden age of construction of large-size brick sewers in its core area. Gradual and continuous deterioration over almost 140 years of its service life had caused occasional blockage, collapses, heavy siltation and water logging, mostly inflicted by lack of adequate and timely maintenance. In 2008, the Kolkata Municipal Corporation embarked on a major undertaking of refurbishing this most ancient and critically important brick sewer by trenchless technology. Its entire length of 2·8 km was rehabilitated using glass-reinforced plastic liners. The total cost of the project was more than £8.5 million (as in 2010) and it took about 2 years to refurbish and recommission (in 2010) this sewer to service.