Ialy Hydropower Plant

A wide sheet of water lies calm among the forested mountains of Chư Păh. This is Ialy Lake, and a visitor on the shore might take it for nothing more than a beautiful lake of the Central Highlands. Some works of engineering show their scale even from far away, and this is one of them.

But behind that peaceful surface stands a complex system of engineering, most of it set deep inside the mountain. To this day it is the largest work in the cascade of hydropower plants on the Sê San River. The Ialy Hydropower Company announces this, and not without reason.

The plant has four generating units with a total capacity of 720 megawatts. By design, it produces about 3.68 billion kilowatt-hours of electricity in an average year. To many families, numbers like these sound abstract. Put another way, each year Ialy makes enough power to light millions of households for many months in a row.

Work began on November 4, 1993, when Prime Minister Võ Văn Kiệt gave the order to start. It was a bold decision, taken while the country was still going through very hard times. More than six years later, on May 12, 2000, the first unit joined the national grid. On April 27, 2002, the plant was officially inaugurated.

One feature is easy to remember. Most of the plant was built underground, inside the mountain. When water from the reservoir is carried to the generating units to make power, it passes through a system of tunnels and does not flow over the ground. That is why, from outside, no giant factory is in sight. Most of the real strength of this work lies below, in the rock of the mountain.

The plant opened to visitors in 2003. The Gia Lai newspaper reported that in the good years nearly 30,000 people came each year. For visitors, the highlight was stepping into the underground machine hall, deep in the mountain.

Ialy has also been expanded. It adds two more generating units with a total capacity of 360 megawatts, and they share the existing plant's dam and reservoir. The first unit joined the grid on November 26, 2024, and the second on December 13, 2024. A State inspection council signed off on the project on June 27, 2025. This shows that the same river and the same reservoir can still yield more power, once better technology and better organization arrive.

On a hilltop stands a memorial. The Gia Lai newspaper describes it as octagonal, a place to give thanks to those who died while the hydropower plants on the Sê San were being built. Behind every great project lie the work, and sometimes the lives, of particular people. It is a place to pause, not for a photograph, but to think of that.

People in Chư Păh still tell one more story. The name Ia Ly is tied to a legend of Rốc and Ly, two young lovers of the mountains and forests of Chư Păh. It is a tale from local tradition, not a recorded event of history. The Sê San River flowed here long before there was a dam, and those names have followed the water through the generations.

Today, from the crest of the dam, the vast lake spreads wide below the green mountains. Two things show at once there: the strength of people who turned a flowing river into light, and the wild beauty that the Central Highlands keeps for itself.