The Matara district in Sri Lanka is in a vicious cycle of flooding and administrative failure. Thousands of paddy farmers in the region have had their livelihoods repeatedly devastated since 2017 and are still waiting for compensation from the government, which has already been included in the budget.

The Nilwala Salinity Barrier: What It Is and Why It Was Built ?

The Nilwala River is 72 km long, stretching from the Sinharaja Forest Reserve to the sea at Matara. It has been threatened by salt water intrusion from the ocean flowing upstream. In order to prevent the salt water from mixing with the fresh water, the Lanka Hydraulic Institute built a salinity barrier in 2017. It is essential for the supply of drinking water without interruption to the 600,000 consumers by the year 2035.

Although the rationale for constructing the salinity barrier is well-intentioned, its aftermath is much more disastrous than the original threat. The danger of saltwater intrusion into the river is limited to a few dry months of the year. The flooding, however, is a year-round disaster, ruining paddy crops, lives, and homes of people in Matara district.

All attempts to alleviate the situation have only made the problem worse. A bypass canal was quickly built due to the increasing public outcry to alleviate the flooding. Unfortunately, the bypass canal is only one-third the size of the river. It is therefore not effective for draining the water while simultaneously providing an avenue for seawater to bypass the barrier when the tide is high. In essence, the structure built to keep the saltwater out has inadvertently allowed the saltwater back into the area. However, the extent of the damage is much worse due to the uncontrolled flooding that now occurs every year since 2019.

The ultimate result is the bitter irony of a structure built to protect the agriculture from the saltwater intrusion now causing a perpetual flooding problem that has caused much worse damage to the agriculture communities than the saltwater intrusion.

A Flooding Crisis That Won’t Recede

Statistics released by the Meteorological Department indicate that although rainfall in the area was higher in the pre-construction period in 2017, the effects and after-effects of the floodwaters were less severe compared to recent years. The worst affected have been the residents. People have had to stay in their homes for over a month, staying in water that is almost two and a half feet deep. Army boats and rafts are the only transport available in these areas.

The destruction caused to agriculture is staggering. Every year since 2017, floods in the area have destroyed around 12,000 acres of paddy fields in 65 Grama Niladhari divisions in the district.

Government Response and Ongoing Measures

The gravity of the crisis has prompted the highest levels of government to take notice. In response, the Secretary to the President called for an urgent investigation into the role of the salinity barrier in flooding and asked the Engineering Department of the University of Peradeniya to assist in a thorough investigation. In terms of immediate solutions to the crisis, there was a proposal to remove sand from the riverbanks that was deposited during construction, lower the sheet pile barriers to allow for water drainage, remove sand from the riverbed, and maintain water pumps that remove excess water from paddy fields.

Compensation Promised, But Not Delivered

While the government has recognized the extent of the loss suffered by the farmers due to the natural disaster, it has included a special compensation package in the budget. However, the farmers have not been compensated so far. In fact, the District Secretary of the Matara District has not initiated the compensation process. On the 11th of this month, the farmers of the area staged a public demonstration under the banner of the Matara United Farmers Rights Protection Force.

It is only natural for the farmers to be frustrated. Every day is like a new season of loss for them. However, the government must bridge the gap between the policy level and the ground level.