When they first set up camp it was under plastic tarps strung from the trees and propped up with sticks. That night the rain came — a drenching tropical downpour that left the group of 100 or so protesters wet, cold and awake through the dark Borneo night.

But after years of petitions and speeches, protesters had crossed a line, that day chasing away engineers drilling for soil and rock samples in preparation for the construction of a dam that would flood the land and villages of all of them. The next day they chased off government officers surveying a nearby mountain that was reportedly due to be quarried for construction materials.

There had been no official approval for the Baram dam — a 168-metre-high concrete construction on the Malaysian state of Sarawak’s second-longest river with a reservoir that would swallow 388 square kilometres and 32 villages, home to 20,000 people. But signs for the dam had gone up, engineers and logging contractors were moving in, and the government had announced the compulsory acquisition of 4000 hectares for an access road.

This was ground zero of a grand-scale development plan, dreamed up in the far-away offices of government ministers, businessmen and bureaucrats, to propel the state into a first-world future. The US$105 billion Sarawak Corridor of Renewable Energy (SCORE) scheme is aimed at effecting a staggering transformation of Sarawak’s economy based on the construction of several coal-fired power plants and at least 12 large hydroelectric dams that would increase installed generation capacity to 20,000 megawatts (25 times the level of 2006 demand), enabling the state to attract the investment of energy-intensive industry.

This wouldn’t be Sarawak’s first big dam — the state has three already, which have displaced close to 15,000 people. But this time the locals had strong leadership, mobile phones and knowledge of how things turned out for the people who previously lost their land to them.

Almost two years to the day from the eviction of the engineers, people started arriving from early afternoon at the blockade by the side of the logging road that connects the villages of the Baram valley with the coastal city of Miri.

Turning up in four-wheel drives and on the backs of trucks from settlements near and far, locals — many in aqua “Stop Baram Dam” T-shirts — shook hands, mingled, laughed, drank sweet coffee and lined up for heaped plates of food prepared by an A-Team of women, before eventually settling into position around the wooden walls of the meeting space (watch the video here).

Also present to mark the two-year anniversary were 30-odd anti-dam activists, hailing from Brazil, Honduras, the US, Indonesia, Cambodia, the Philippines and other parts of Malaysia, who were in Sarawak for an event dubbed the “World Indigenous Summit on Environment and Rivers” (WISER).

With the exception of the Americans — brothers from the Yurok Tribe of northern California, who were campaigning for the decommissioning of existing dams — the delegates represented indigenous communities fighting a resurgence of large-scale dam-building in developing countries around the world.

In the mid-1990s big hydropower fell into disrepute as controversy grew around megaprojects like India’s Sardar Sarovar and China’s Three Gorges dams — which displaced an estimated 350,000 and 1.2 million people respectively. But in the last few years big dam projects have made it back onto the drawing boards of development banks and are booming, particularly in Asia, Latin America and Africa, where they are being carried out under sweeping state development policies.

The WISER activists tell of downriver flooding, upriver siltation, poisoned water, depleted fish stocks, the loss of access to forest products, and loss of incomes, livelihoods, homes, culture and tradition as a result of dams already underway in their countries and of repressive government responses to people trying to stop new ones going ahead.

“Normally people lose their lands, identities and forest, and also biodiversity is destroyed because of the dams,” said WISER delegate Samnang Dam of the impacts on indigenous communities of a major hydropower expansion underway in Cambodia.

Dam is a community representative from Stung Treng province, where the 400-megawatt Lower Sesan 2 dam is under construction on a major tributary of the Mekong — seriously threatening water and sediment flows, fish stocks and fish species throughout the Mekong basin, according to environmentalists.

There had been a lack of consultation of affected people on the project, the 335-square kilometre reservoir of which will force about 5000 mainly indigenous inhabitants from their homes, Dam said. As in Baram, logging of the reservoir area had already started although people still had no information on the details of their proposed resettlement or compensation.

Despite the political climate in Cambodia making activism dangerous, people in the area were determined to stay on their land, Dam told Crikey, and would “fight until they die”.

In the Cordillera region of the Philippines, Claudine Panayo of the Cordillera People’s Alliance told the blockade crowd, the Igorot indigenous people threatened by construction of the 240-megawatt Alimit dam project have had to learn how to assert themselves.

“At first they were very shy. They are conservative, they don’t want war.”

But confronted by the loss of their ancestral lands and a lack of regard for their right to them, they started to organise, and are now running a blockade with women on the front line and men rolling boulders down the mountain to stop construction equipment reaching the area, Panayo said.

Government and big business have long considered the mineral- and forest-rich Ifugao province on the country’s main island where the dam is to be built “a resource base”, and developers of big projects there pay only lip service to the principle of free, prior and informed consent of indigenous inhabitants of the area, consulting just with local officials and claiming to have the consent of the people, according to Panayo.

It is a familiar story to Baram locals, whose state-paid indigenous leaders are largely in step with the government’s plans and make occasional media appearances to claim to represent their people’s support for the dam.

In July Sarawak’s Chief Minister Adenan Satem — who succeeded longtime leader Taib Mahmud in February 2014 — announced a moratorium on the Baram project after meeting with a delegation that included alternative energy researchers from the University of California. While some observers believe the state government may be genuinely rethinking its energy plans in Sarawak, many dam opponents are wary, given state elections are imminent and the Chief Minister has requested that the blockades be dismantled.

Back in Miri, at the end of the WISER event, the international group released a “declaration on dams and the rights of indigenous peoples”.

“Our individual struggles share many similarities that reflect the realities of an unsustainable world structure based on uncontrolled extraction,” the document states, demanding that governments, companies, development agencies, donor institutions and investors “recognise that dams are not a solution to climate change”, stop carrying out projects that do not have the free prior and informed consent of impacted populations and cancel the Baram dam for good.

The two blockades of the Baram dam site continue.