An overdue reckoning with nature

Flooding in Colombo is hardly a new phenomenon. Successive governments and municipal administrations have attempted, with varying degrees of success, to address the problem through drainage improvements, canal rehabilitation and other flood mitigation measures. Yet the flooding witnessed last week is a stark reminder that much more needs to be done. More importantly, it highlights the need to rethink how we approach the problem. Colombo’s flooding cannot be treated simply as a failure of its drainage infrastructure. It is, at its heart, the consequence of decades of encroachment on nature.

The first reality we must acknowledge is that Colombo is built on a floodplain. Much of the present-day metropolitan area lies within the natural floodplain of the Kelani River. As one of two major wet-zone rivers, the Kelani carries enormous volumes of water from the central hills towards the western coast. Historically, as it approached the sea, the river had extensive marshlands, wetlands and low-lying areas into which its waters could naturally spread during periods of heavy rainfall.

These floodplains were an integral part of the natural drainage system, acting as enormous reservoirs that absorbed excess water and released it gradually. From the wetlands around Kotte to the marshes further north towards Muthurajawela, this interconnected landscape played a vital role in regulating water flows and protecting settlements from flooding.

Over the years, however, much of this natural infrastructure has been steadily destroyed. Land reclamation, unauthorised filling, urban expansion and infrastructure development have progressively reduced the space available for water. Areas that once absorbed floodwaters have been converted into residential, commercial and industrial developments. Water, however, does not simply disappear because the land on which it once flowed has been filled. It will find somewhere else to go, often into homes, roads and public spaces.

Addressing this challenge requires us to look back at nature and recognise the functions that its original landscape performed. Restoring, as far as possible, the marshlands, wetlands and floodplains that once accommodated excess water must become a central component of any long-term flood management strategy. Improving drainage canals and pumping capacity is important, but these measures alone cannot compensate for the wholesale loss of natural water retention areas.

Such an approach will inevitably involve difficult decisions. In certain areas, restoring wetlands and reclaiming natural floodplains may require the relocation of communities currently living on land that was once marshland. This is a politically and socially sensitive undertaking. No Government can pursue such a policy without recognising the human consequences and ensuring that affected families receive fair compensation, suitable alternative housing and the necessary support to rebuild their lives.

This is not a responsibility that can be left solely to the Colombo Municipal Council or the Urban Development Authority. It requires a coordinated, Government-wide approach involving the relevant ministries, local authorities, environmental agencies, water management institutions and urban planning bodies. It also demands political leadership capable of looking beyond electoral cycles and short-term development interests.

Colombo needs a comprehensive flood management plan that integrates urban development, environmental restoration, drainage infrastructure and land-use regulation. Crucially, it must prevent further encroachment on wetlands and ensure that future development respects the natural geography of the city. Colombo’s flooding is ultimately a reckoning with the way we have altered the landscape on which the city was built. Unless we are prepared to confront that reality and make the difficult decisions it demands, we will continue to pay an increasingly heavy price every time the rains arrive.