Flood protection dyke using local technology

Vetiver grass being used at under construction 21-km dyke in Pabna

For the first time in the country a flood protection dyke is being constructed following local technology. In protection of slopes of the dyke, sand mixed concrete in environment-friendly jute-made bags is being used instead of geo sacks. 

Moreover, locally produced vetiver grass, popularly known to all as binna grass, will be sown on the slope in order to prevent landslide during heavy rainfall.

Mentionable, the vetiver grass is the key element in a low cost and efficient system for soil and water conservation, infrastructure stabilisation, pollution control, prevention of storm damage and many other environmental protection applications. 

According to the findings of a research conducted by Bangladesh University of Engineering technology teacher Professor Shariful Islam, this vetiver grass can be successfully used in construction of flood protection embankment.

This vetiver grass is being sown at the risk-prone points of the under construction 21-km flood protection dyke on the banks of Jamuna and Hurasagar rivers in Pabna.

The dyke construction sources said socio-economic condition thousands of people from erosion-prone areas of Bera upazila in the district would be drastically changed after the construction of the embankment. 

Bera Water Development Board sources said the embankment is being constructed under a Water Resources Ministry project styled ‘Flood and River Bank Erosion Risk Management Investment Programme (TRANS-1). 

The dam stretching from Pechakola shoal under Bera upazila to Ratankandi area at Ahmedpur union in Sirajganj is being built spending Tk 124.50 crore in land acquirement and Tk 135.50 crore in construction, said sources.

“Already 55 percent construction works of the dam have been completed. The dam being constructed on the left banks of Jamuna and Hurasagar rivers would have four vent regulators to resolve water stagnation in Farmlands under WDB project,” sources said, adding that vetiver grass would be sown on both sides of the dam soil does not get washed away during heavy rainfall. They claimed that farmers would be able to cultivate lands throughout the year after the construction is completed, farming three crops from a farmland.

Several farmers including Yusuf Ali Altaf Hossain of Verakola village in Pechakola shoal told the Bangladesh Post: “Earlier we could not sell our produced crops at fair prices as the communication to distant wholesale markets was limited. We are eagerly waiting for the completion of the dam which would help us taking our crops to far away markets.”

Bera WDB executive engineer Ahsan Habib said as per the instruction of Prime Minister Sheikh Hasina, the dam is being constructed with sand extracted through dredging from the riverbed, without damaging the adjacent arable lands. As a result, the navigability of the rivers is being increased besides protecting the riverbanks from floods. 

“As the project is being implemented in a remote area, it would expectedly change the socio-economic scenario of the entire region,” he added.

Pabna Irrigation and Rural Development Project executive engineer Md Abdul Hamid, “For the first time in the country, a flood protection dam is being constructed following local technology of protecting slopes with vetiver grass. If the implemented project becomes sustainable and successful, the method would be widely used in the future in construction of flood protection embankments.”