Bamboo as erosion control

Krabi, in southern Thailand, is famous for its natural beauty. Iconic images from Krabi province, such the one of the pier at Bamboo Island, shown here, do not tell the whole story though. Less than 40 kilometres across the sea, the fishing village of Ban Khlong Prasong is slowly being washed away.

Previously, the village was surrounded by beautiful sandy beaches and mangrove forests that offered some protection against erosion. Now, mud has replaced the clean sand. Waves have eroded more than one kilometre of coastline in some places, including much of the mangrove forest.

After the tsunami in 2004, Krabi local government authorities built a 2m-high concrete wall along the beach in an attempt to mitigate the erosion and protect houses. Instead, seawater seeps under the concrete causing the land to subside further. The concrete wall has also changed the pattern of the waves, causing more problems.

Bamboo to the rescue (again)

Supported by a number of NGOs, villagers have adopted an idea from a village in another province suffering the same problem. Bamboo fences are being constructed. These are permeable, temporary structures. So far, 600 metres of bamboo barrier is in place.

Interviewed for the Bangkok Post, villager Kanit says, “The wave varies from place to place. Here, we need to put the top of the bamboo into the sand and make a small hole along the trunk to allow sand to seep in and make the bamboo stand solidly in the sea.”

Since the bamboo fences were ‘planted,’ sand and soil are gradually returning to the beach. Small aquatic animals such as molluscs and crabs are observed now, and the mangrove forest is recovering. The roots of the mangroves help with binding the soil and in establishing micro-organisms which further assist in stabilisation. Stabilisation starts from the land side and gradually moves toward the sea.

Disclosure: I’m a great fan of mangroves. In a previous life I drove a small river cruise vessel on a river that hosts over 30 species of mangroves in only a small area. The mangroves were my favourite part of the tour and I managed to get many a sleepy visitor awake and excited (or at least interested) in the wonders of mangrove forests.

Sources:

• Bangkok Post
• The Nation
• Soonabai Pirojsha Godrej Marine Ecology Centre

Bamboo on the Internet for September

A compilation of posts on the Internet about bamboo from Google Alerts in September:

• Inspired by the La Balsas rafts, the Shearwater Steiner School in northern NSW made a bamboo raft and took a trip. If this looks tempting, you might like to try it in Borneo. Insect repellent tops the list of things to bring for this trip.

• Like the look of bamboo but worry about it invading? Try artificial bamboo. Follow the links for pictures.

Bamboo house

• Online architecture and design magazine Dezeen featured a prototype bamboo house in Vietnam designed to withstand floods up to three metres above ground. From there I followed links to posts about the stunning Wind and Water Bar and more light and spacious low-cost bamboo housing.