Vietnamese Updates: The fight against sea erosion in the West (10 Apr 2013)

The fight against sea erosion in the West
Thứ tư, ngày 10 tháng 04 năm 2013 cập nhật lúc 03:26

In recent years, the erosion of the sea dike in the west of Ca Mau peninsula is always concernof many local people. Natural disasters such as sea level rise, wave erosion in coastline from Ca Mau to Kien Giang and moreover, reduced areas of protective forests have threatenedlivelihoods of thousands of locals. Local government and people are struggling tocombat this danger every day.

Serious sea erosion

Mr. Nguyen Long Hoai, the Director of Ca MauDepartment of Water Resources said, dyke erosionin the west has been quite serious andcomplicated since 2009. Except for alluvial areas inthe most southern point Ca Mau, over 80% of CaMau coast stretching from east to west areeffected by sea erosion. There are four critical areas in Phu Tan, Ganh Hao, Dat Mui and Khai Long. There are over 100 points with a total length landslide over 10km which are under bad conditions in the coastline. That threatens activities and production of nearly 26,000 households 129.000hectares of agricultural andaquaculture land.

Compared to the eastern coast, sea erosion occurs seriously in the western coast. Earlier, sea dyke in the west was protected by ahundred-kilometer mangrove belt extending from adjacent areas of Ca Mau - Kien Giang until Rach Cheo. Now, the protective forest is almost destroyed, sea waves reach to the foot of sea dyke in many places, even some places have absolutely no protection dyke. To deal with this situation, Ca Mau province has decided to declare dyke emergency in order to protect the dyke in the southwest monsoon andwhen big waves and strong erosion take place.

Along the west coastal dyke behind protective forest range, about 300 km from Kien Luong, Hon Dat, Chau Thanh, An Bien and An Minh,Ha Tien town, Rach Gia (Kien Giang province), U Minh, Tran Van Thoi, Phu Tan (Ca Mau province) which are separated by rivers feedinginto the sea, are under bad conditions because there is no protective forests and sea waves encroachment to the dyke foundation.

Anti-sea erosion

When landslide occurs, houses and people will have to move out. But it is impossible to give up forever, because of limited land, people are trying to find ways to combat erosion. However, all measures seem to be unfeasible against salty and powerful sea water.

While making plans for building the new dyke is not feasible, it is found that the best anti-erosion is to keep the forest, but if keeping the forest, it is essential to find a way to limit direct impact of waves. In 2009, reinforced piled embankments on ground piloted 300m long inthe west coast (U Minh district). The design of a solid fence with two rows of parallel concrete piles, separated by about two meters and between the two rows, moderate sized rocks are filled to keep them stable between the concrete piles when waves pass. The permanentfences with concrete piles are to prevent the waves interfere and to keep mud and alluvium for mangrove restoration. After the first phase of construction, monitoring results showed that the amount of sediment in the fence increased, shore erosion status improved. At somenatural areas, the mangroves regeneration is also stable.

Deputy Director of the Ca Mau Provincial Department of Agriculture and Rural Development To Quoc Nam said, this concrete pile embankment‘s life expectancy is at least 15 years. After five years, trees grow up, piles of concrete and stones will be pulled out andcontinue to set up again 50m away in the sea. Accordingly, forest and land will gradually encroach beyond the sea. "

Ca Mau Province has submitted proposals to ask for supports to upgrade sea dikes in the west, including the construction of embankmentagainst erosion in critical sections with a length of 6, 4km by this method. The estimated cost will be over VND 3,000 billion.

According to Nguyen Long Hoai, Japanese research experts have praised and expressed their desires to learn and exchange experienceof this model. If getting supports from the central government, Ca Mau local government will promote the construction of this fence forsome other critical sections in the coming time.

For more information: 
http://www.monre.gov.vn/v35/default.aspx?tabid=675&CateID=80&ID=126587&Code=ZSLR126587