Where nature grows

Where nature grows

King's concern transforms Phetchaburi's waste into abundant mangrove ecosystem

Where nature grows
The mangrove forest covers an area of 642 rai.

Bicycles for rent are placed not far from the entrance gate of the royally-initiated Laem Phak Bia Environmental Research and Development Project in Phetchaburi's Ban Laem district. At the other side of the gate are souvenir outlets with a big signboard displaying the words Lan Pholuang in Thai and "Ban Laem Products Market" in English.

The sign ensures me that I am at the right place of the royally-initiated project, which looks much different from my last visit a decade ago. There are more facilities to serve visitors.

Tourists are not allowed to drive their vehicles inside the project. You can rent a bicycle or ride a free shuttle service to explore the place. I chose the shuttle so that I can roam around the project with a guide before starting off by myself.

The 1,135 rai project was initiated by King Bhumibol Adulyadej on Sept 12, 1990, to solve two classic problems of urban communities. The problems were polluted water and poor waste management, according to Sukanya Suchat, a trainee guide.

In the past, the city of Phetchaburi didn't have a water treatment system. Water used by households was discharged directly to Phetchaburi River, leading to its poor condition. The river is an important resource for an ancient ceremony called Thue Nam Phiphatsattaya. It is the drinking holy water ceremony for showing one's allegiance to king and country. In addition, locals also used the water for consumption and farming.

King Bhumibol was concerned about environmental issues. He initiated the project as a model of a simple and environmentally friendly method that can treat wastewater and urban waste in a natural way.

Chaipattana Foundation joined forces with the Royal Irrigation Department and Phetchaburi Municipality to carry on the royal initiative. They built a pumping station in the city to push the wastewater through a 18.5km pipeline to the Laem Phak Bia project in the coastal area.

Led by Prof Dr Kasem Chankaew, an environmental expert and a former dean of the Environmental Faculty of Kasetsat University, the project applied simple low-investment methods including an oxidation pond treatment system, grass filtration system, artificially constructed wetland system, and mangrove ecosystem.

So when you start the tour inside the project, you will notice the scent of wastewater from the first pond where sewage from the city is stored. But the smell disappears after we tour inside the project.

"We have five separate shallow ponds built to treat wastewater before releasing it through the mangrove forest and into the sea," said the guide. The wastewater remains in the first sedimentation pond for about a week before being flowed over to other ponds where microorganisms are used for digesting organic matter and with combination of wind and sunlight to add oxygen into water of each of the ponds.

To ensure the quality of water, fish are released into the second to fifth ponds.

"We release freshwater fish including pla nil [tilapia] and pla yisok [rohu] into the ponds. The quality of water is safe enough for fish to survive," she said.

Every six months, the centre will allow vendors to harvest fish in the ponds. They can catch about 35 tonnes of fish at a time. The earnings from selling fish is donated to local schools, temples and communities as well as for buying petrol for the shuttle buses to service tourists inside the project for free, she added.

In addition, the project also has a grass filtration system. Six types of plants are grown such as thup ruesi (bulrush), kok klom (papyrus sedges) and ya phaek (Indonesian vetiver). Their roots can add oxygen to wastewater while contaminants are trapped inside each planting plot when the water runs through the grasses.

The artificial wetland system, on the other hand, carries the same idea of the grass filtration system, but the artificial wetland system is operated on a larger scale while wastewater is stored and later drained.

The plants can be used as materials for locals to weave handbags and mats, said the guide.

The project can treat more than 3,000m³ of wastewater per day or 60% of wastewater from the city.

While still on the shuttle bus, the guide pointed to small green shrubs grown next to the ponds. It is phak bia (sea purslane), the plant that the project took its name from. The plant leaves can be eaten, said the guide. Locals like to use it for making thod man (spicy, deep-fried patties of fish or shrimp).

Also grown well in salty areas not far from phak bia shrubs is ton chakhram (annual sea blite). Its small leaves are used for cooking kaeng som (a mild sweet-sour-spicy soup) or for making spicy salad dishes like yum chakhram with shrimp and minced pork.

Furthermore the project has large cement boxes built to decompose organic waste, accounting for 50% of household waste. The technique is very simple. It uses four layers of soil. The first layer is soil and topped with solid waste for about 20cm in height and covered by 5cm of soil. The process is repeated two more times. The last layer must be 20cm-thick soil in order to prevent odour.

"The result is very impressive as we can turn waste into fertiliser," she said.

The fertiliser has been used for planting trees, growing rice and planting mangrove seedlings. From dry land without a tree three decades ago, today the mangrove forest of the project spans over 642 rai plot of land.

When the shuttle bus reaches the mangrove forest, it makes a stop for visitors to use a 850m walkway built through the mangrove forest. It ends at the sea.

"The mangrove forest is not only a nursery for fish, shrimps and crabs, but it is also the last natural wastewater treatment process of the project," said the guide.

Along the walkway, you can spot the big eyes of mudskippers, many marsh crabs and birds.

"When the project started in 1990, we found 50 types of birds in the area. Today the latest record shows that there are more than 280 kinds of birds found in the centre such as white egrets, painted stork, cormorant and black-winged stilt," she said, adding that the centre is also home to 400 water monitors.

The large lizard helps control the fish population and the largest lizard that was found is about 3m long, she said, adding that no one hunts the animal. It is one of the indicators of the project's healthy nature.

The tour ends at the starting point. The guide encourages visitors to try applying some of their knowledge of wastewater and waste treatment at home.

"You can apply the technique in a small scale and according to space available at your home or your community. With a simple act, you can help reduce household waste and improve our environment," she said.

Laem Phak Bia Environmental Research and Development Project can be reached by Road 4028 linking Samut Songkhram and Hat Chao Samran in Phetchaburi.

The project is open daily from 8.30am to 4.30pm. There is no entrance fee, but visitors are required to register their names before visiting the site.

A shuttle bus is provided without a service charge. The service is available every 30 minutes. The last round is at 4pm.

For more information, visit lerdilc.com or call 02-579-2116.

Canna lilies are in full bloom showing their vivid colours at the entrance gate. The project also grows sunn hemp as fertiliser for soil before planting rice.

The sedimentation pond is the first in the project's wastewater treatment process.

Fishing communities benefit from the healthy mangrove forest of the Laem Phak Bia project.

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