Tamolitch Falls, Seasonal waterfall in Willamette National Forest, Oregon, US.

Tamolitch Falls is a waterfall in Willamette National Forest, Oregon, that drops into a deep pool of clear water. The water reflects intense blue tones from the underlying volcanic rock, creating a striking appearance.

The waterfall flowed continuously until the 1960s, when water was redirected for hydroelectric power and altered the site. Since then it has run seasonally, most notably during spring snowmelt.

The pool sits at the base of a waterfall that stopped flowing constantly after water was diverted for hydroelectric use in the 1960s; the stream now runs underground and surfaces below the falls. The McKenzie River Trail, which leads here, is shared by hikers, bikers, runners and leashed dogs, and parking fills quickly in spring and summer.

The pool is reached by a 3.6-mile (5.8 km) out-and-back walk on the McKenzie River Trail, with 285 feet (87 m) of elevation gain; the path climbs beside a cliff, crosses a dry riverbed and an old lava flow, and passes hazardous steep cliffs. Parking fills quickly in spring and summer, and cellphone service is minimal to none, which complicates rescue in the remote terrain.

The pool is 30 feet (9.1 m) deep but looks much shallower because of the water's clarity. Its temperature of about 38 °F (3 °C) is too cold for even microorganisms to live in, and such low temperatures have proven deadly to people who tried to swim.