Yamdrok Lake is one of Tibet's four "Great Wrathful Lakes," sacred bodies of water believed to be the dwelling places of protective deities invested with special spiritual powers. Its guardian is the goddess Dorje Gegkyi Tso, and the lake is considered divinatory -- used by everyone from the Dalai Lama to local villagers to seek guidance through pilgrimage. The lake, its islands, and the surrounding landscape are closely associated with Padmasambhava, the eighth-century figure known as the Second Buddha, who is credited with bringing Buddhism to Tibet. On one of the lake's islands stands Pede Dzong, an old fort whose stone walls have watched over these waters for centuries. Today, pilgrims and tourists walk the lake's perimeter together, though their purposes differ. For the pilgrims, each step around the lake is an act of devotion, a circumambulation that brings them closer to the sacred geography their tradition maps onto this landscape.

At nearly four and a half kilometers above sea level, Yamdrok Lake exists in a climate of extremes. Winters are long, cold, and very dry; the lake freezes over entirely. Summers are short, cool, and wet. The difference between day and night temperatures is dramatic -- warm sunlight giving way to bitter cold once the sun drops behind the mountains. The climate hovers at the intersection of cold steppe, alpine tundra, and subarctic classifications, as if the atmosphere cannot quite decide what to make of this place. The lake averages 30 meters deep, reaching 60 meters at its lowest point. Snow-capped mountains ring the water on all sides, feeding it through countless small streams that cascade down from glaciers and snowfields. To the west lies the Tibetan town of Gyantse; to the northeast, Lhasa. Between them, the lake occupies a world that feels set apart from both.

Yamdrok Lake is not only sacred -- it is economically vital. From April to October, fishermen work the lake's shoals, selling their catch at markets in Lhasa. The islands that dot the lake serve double duty as rich pasture land, where local herdsmen graze their animals on grasses fed by the mineral-rich waters and mountain runoff. This practical relationship with the lake coexists with its spiritual significance without apparent contradiction. The people who fish these waters and graze these islands are often the same people who make pilgrimages along the shoreline. Sacred and functional are not opposing categories here; they are simply different aspects of the same place.

Near the small village of Baidi at the lake's western end, the Yamdrok Hydropower Station began generating electricity in the late 1990s -- the largest power station in Tibet. The project drew water from the lake through tunnels to turbines below, discharging it into the Yarlung Tsangpo River. The station was designed as a pumped-storage system that would return water to the lake during off-peak hours, but the pumping has proven impractical. The result is a slow, steady drawdown of a lake that has no major river feeding it, only rain and snowmelt. For a body of water that Tibetans believe holds the spirit of their homeland, the implications extend beyond hydrology. The turquoise that draws visitors from around the world -- that mineral-saturated color born of the lake's isolation as a nearly closed system -- depends on a balance of inflow and evaporation that human engineering has begun to tip.