The engineers who helped build this dam came from a country that has since ceased to exist. Yugoslavia lent its technical support to the Kirirom I hydroelectric plant in the 1960s, on a pine-forested plateau in the eastern Cardamom Mountains about 110 kilometres southwest of Phnom Penh. The plant came online in 1965, the first hydroelectric station Cambodia ever had. Then it stopped for twenty-seven years - and when it started again, in 2002, it was a Chinese state enterprise that had rebuilt it. The machinery is small, the numbers are unimpressive, and almost nothing about modern Cambodia is legible in a single object more clearly.
The plateau got its name from a king. In the 1930s King Sisowath Monivong renamed the area Kirirom - Happiness Mountain - having found it a pleasant escape from the heat of the plain, much as the French were then doing on Bokor further south. Before that it was Phnom Vorvong Sorvong, after an old Cambodian legend of two princely brothers. The ground sits at a mean elevation of around 675 metres and is covered in something Cambodia otherwise has very little of: open pine forest, cool and dry-smelling, with granite outcrops and boulder fields breaking through. In 1993 the government made Kirirom the country's first officially designated national park, 283.75 square kilometres in Phnom Sruoch District, Kampong Speu Province. The dam sits inside it.
By the standards of the dams Cambodia builds now, Kirirom 1 is a rounding error. It is an earth-core rockfill embankment, 34 metres high and 343 metres long, backing up a reservoir on the plateau and driving two generating units of six megawatts each - twelve megawatts in total. That is roughly one-twentieth of the Stung Tatai dam commissioned in the Cardamoms in 2014, and a thirty-third of the Lower Sesan 2 completed in 2017. But scale is not what makes it interesting. In the mid-1960s, a country with almost no grid at all put a functioning hydroelectric plant in the mountains, and it worked.
Then the power went off. When the Khmer Rouge took the country in April 1975, the plant was partially destroyed and generation stopped entirely. It is worth being precise about why a piece of infrastructure would simply cease: the regime emptied Cambodia's cities, abolished money and markets, and treated education and technical training as evidence of guilt. Engineers, technicians and anyone who could read a schematic were among the people it killed first. A hydroelectric plant is not a thing you can mothball and walk away from; it needs people who understand it, continuously, and those people were the ones being destroyed. The turbines at Kirirom sat in the pine forest for the better part of three decades, and the transmission line to Phnom Penh carried nothing.
The restart was a commercial transaction. In 1999 the China Electric Power Technology Import and Export Corporation, a Chinese state-owned enterprise, was contracted to rebuild the plant at a cost of US$24 million under a 30-year build-operate-transfer agreement - it would run the station and keep the revenue, then hand it over. A power purchase agreement with Electricité du Cambodge was signed on 28 July 2000, the Council for the Development of Cambodia approved the project on 29 December that year, and in May 2002 Kirirom I generated electricity again for the first time since 1975. Power now runs to Kampong Speu Province and the capital over 120 kilometres of 115-kilovolt line. A second station on the plateau, Kirirom 3, added 18 megawatts in 2013.
Visitors come to Kirirom for the pine air and the waterfalls and generally do not go looking for a 34-metre embankment. They should. Read the dates in order - Yugoslav assistance in the 1960s, silence from 1975, a Chinese state company in 1999, back online in 2002 - and you have the country's postwar history in four entries: non-aligned experiment, catastrophe, and then a reconstruction financed on terms set largely in Beijing. The plant supplies a fraction of a percent of Cambodia's electricity today. What it holds is the record of who was willing to build here, and when.
Located at 11.24°N, 104.03°E in Kirirom National Park, on the Kirirom plateau in the eastern Cardamom Mountains roughly 110 km southwest of Phnom Penh, at a mean plateau elevation near 675 m (2,215 ft). Visual landmarks: the reservoir behind the 343 m embankment, the distinctive pale-green pine forest that distinguishes this plateau from the darker evergreen canopy on all sides, and the transmission corridor running northeast toward the capital. Recommended viewing altitude 3,000-5,000 ft AGL. Nearby airports: Phnom Penh International (VDPP) about 110 km northeast, Sihanoukville International (VDSV) to the southwest, Kampot (VDKT) to the south. The plateau is cooler and clearer than the surrounding lowlands; expect afternoon convective build-ups over the ridge during the May-October southwest monsoon.