Black Rock Springs & the Trout Hatchery

Off to your right a side road heads east toward Black Rock — and toward one of the Owens Valley's quieter water-politics stories. The dark, broken ground scattered across this stretch is lava: you're skirting the southern edge of the Big Pine volcanic field, a sprawl of cinder cones and basalt flows, some only a few tens of thousands of years old. That black rock gave the place its name.

Near here once rose Black Rock Springs, a strong artesian spring pushing 12 to 15 cubic feet of water a second at a steady 59 degrees. In 1941 a trout-rearing operation opened on that flow: the first fall, 450,000 rainbow fingerlings went into the ponds, and by the next spring crews had raised more than 274,000 fish. The spring water ran through the ponds and then, less than a quarter mile away, straight into the Los Angeles Aqueduct — fish farming and city water-gathering sharing the same channel.

Then the spring died. When Los Angeles enlarged its aqueduct and began heavy groundwater pumping in 1970 to fill the new capacity, Black Rock Springs stopped flowing. The natural spring was simply replaced by wells; today the hatchery runs on pumped water that goes, as before, into the aqueduct. It's a small, exact illustration of the larger valley story — water that once surfaced on its own now lifted from underground and sent south.

The hatchery is still working. After the Mount Whitney hatchery near Independence was knocked out by a debris slide, Black Rock took over much of the job of stocking the Eastern Sierra's lakes and streams with trout.