Flooding has devasted many parts of Thailand this year.
More than 50 people lost their lives in the North earlier in the year, and at least 25 have been killed in the South more recently. While climate change is partly responsible, there are specific man-made causes for the disaster, Pianporn "Pai" Deetes told Bangkok Post's "Deeper Dive" vodcast.
The Southeast Asia programme director for the NGO International Rivers identified three specific roots for the problem: deforestation, dams and encroachment.
It is ironic that a trigger for flooding is also responsible for the annual PM2.5 haze in northern Thailand -- deforestation to plant corn for animal feed, and the subsequent burning of the cornfields -- leading to "half flood, half haze", as Ms Pianporn described locals' plight.
Aside from burning down the forests on both sides of the border with Myanmar to plant maize, mining is also a factor, particularly in neighbouring Shan State.
"Satellite imagery showed they are mining -- could be gold mining, and it seems to be illegal… in Myanmar after the coup three years ago, there are no such laws in place," she told the vodcast.
"In Myanmar there are less reports because of the absence of journalism or civil society space.
"So there's lots of activities, like open sites for mining in the upper reaches of the Mae Sai River as well as plantations, monocrop plantations that can be a major cause of the mud flood in Mae Sai district of Chiang Rai as well as Tachileik district of Myanmar.
"The deforestation does worsen or exacerbate the flood effect on population, it causes a large volume of mud and sediment flowing into the cities, the villages and the towns.
"The recovery is still happening in Mae Sai. The heavy machines are still working to bring the sediment out, all mud out of their houses of people,'' Ms Pianporn said.
The spreading number of dams upstream is also a contributing cause of the flooding in northern Thailand.
"The flood that happened during the past two months has something to do with dams on the Mekong too, because that rain also happened in southern Yunnan [in China] and the dams up there have to release water," the activist said.
"We can see the water from the flood area in Chiang Rai drained slower because of the high volume [of water] along the Mekong River.
"So, it is important in the case of the Mekong, or in the case of any international rivers like this, for governments to talk to each other ... We are not blaming anyone, [but] I believe that China, as an upstream superpower needs to listen to its downstream neighbours because we are sharing this water course together.
"The Office of Water Resources has submitted a letter to China to asking them to operate the dams with recognition of [their impact on] downstream areas and floods,'' she said.
Pianporn: Don't work against nature
Aside from deforestation and dams, Ms Pianporn identified encroachment on the rivers themselves as a major cause of flooding.
"I discussed with one historian…the real cause of this flood in Chiang Rai city. He showed the old imagery of ancient Chiang Rai…even my foundation, my mum's foundation office in the outskirts of Chiang Rai town, it happens to be on the old river course.
"So our office is right there on the old river! And we didn't know that,'' she said.
Building flood walls, she argues, is not the answer.
"In many cases like Sukhothai or Nakhon Sawan… they have a flood wall between the river and the city. But many cases around the world show that flood walls can be very dangerous because once it breaks, the impact could be even more severe.
"So I think for the cities or towns in the northern region, I will recommend nature-based solutions,'' she said.
Ms Pianporn is a supporter of "sponge cities", integrating towns with wetlands and lakes.
But in some cases, she said, "moving communities out of very dangerous areas to other places" is inevitable. But this should not be forced, she said, noting it should be carried out in an inclusive manner, with affected residents adequately compensated.
The overriding need right now, Ms Pianporn told the vodcast, is to start addressing the issues and working with nature, rather than against it -- and cooperation from stakeholders is needed.
"I think the most important thing is that to recognise the real problem and identify the key factors and consult with multiple stakeholders, the experts, the engineers, the farmers, the urban dwellers and academics," she said.
"We should find the solution together, not just Royal Irrigation Department or Ministry of Interior alone. I believe that collectively we can, but I still don't see this process of meaningful consultation with different stakeholders," Ms Pianporn said.
Watch the full vodcast by clicking below or searching for 'Deeper Dive Thailand' wherever you get your podcasts.