After hearing of the plight of farmers amid the water shortage, durian growers in Nonthaburi realised they would face a similar problem, despite their plantations being full of water.
Thammarat Khiokaeo, left, measures salinity in water as he tests water to be used for tending durian farms in Nonthaburi. Tawatchai Kemgumnerd
The fruit farmers found the water they were taking from the Chao Phraya River had become mixed with sea water, which is too salty and dangerous for their crops.
As the drought has hit many parts of the country, dashing hopes for more run-off water to push sea water out of the Chao Phraya River, some are pinning their hopes on a so-called "desalination filter", although it has not yet been scientifically tested.
"I just want to give it a try," said Sawai Thatsaniyawet, who grows durians on 15 rai of land in tambon Bang Rak Noi, Nonthaburi's Muang district. She said the salt in the water had reached 2.22ppt (part per thousand) — too salty for crops to thrive.
Last year, 70% of her durian plantation died from a lack of fresh water.
Offering hope of better times this year, Ms Sawai said she learned about the desalination technique from Thammarat Khiokaeo, an owner of a longan plantation from Chiang Mai's Doi Tao district.
He had worked out how to remove unwanted contaminants from water using a simple filter made from a 200-litre container filled with a mix of filtering materials.
"Just use it and pray it will work," Ms Sawai said as she welcomed Mr Thammarat to her plantation yesterday. "This should be better than waiting for rain because I have no idea when it will fall."
The Meteorology Department earlier forecast that rain will arrive at the end of this month, soaking arid farmland and replenishing almost empty reservoirs.
While weather patterns seem complicated to Ms Sawai, the filtering container and Mr Thammarat's easy explanation of how it can reduce salinity of water appears more accessible.
At first glance, the container is similar to a water filter made for a school science project. Inside the device are layers of pebbles, charcoal, fibreglass and sand. Small holes were perforated at the bottom to allow filtered water to pass through.
"It helped me filter contaminated water on my farmland," Mr Thammarat said.
His plantation has depended on underground water, which was previously unable to be used due to its strong unpleasant smell and red colour suspected to result from iron minerals. The filter can remove most of these contaminants, so Mr Thammarat believes it can do the same with salty water. Most importantly, the device can be put together using everyday materials and costs less than 2,000 baht.
Mr Thammarat said it was not a good idea to depend only on water distribution from the government. "There are many farmers waiting for it and that means we are in a queue," he said.
Unfortunately, his efforts were not very successful yesterday as his filter only slightly decreased salinity levels from 2.22 ppt to 1.92, or in some cases remained almost unchanged. The acceptable salinity of water in durian plantations is 0.3 ppt.
But the device brought smiles to many durian growers observing the experiment. Benchawan Oaisun, who farms on six rai of land, said she would use it on her plantation when salinity levels are not too high.
Suwattana Chittaladakon, an adviser to the Engineering Institute of Thailand, said the device can only deal with colour and turbidity of water, and that more advanced technology was needed to reduce salinity.
But for durian growers like Ms Sawai and Ms Benchawan, the device at least gives them hopes of being able to water their fruits with water other than tap water, which is now also diminishing.