Friday, December 20, 2013

Hike past fumaroles, mudpots, boiling pools

Bumpass Hell Trail, Lassen Volcanic National Park.
Topo map of Bumpass Hell Trail.
A fantastical world of steaming pools and multi-colored soils await day hikers on the Bumpass Hell Trail at Lassen Volcanic National Park.

At 3-miles round trip, Bumpass marks the best day hiking trail at the northern California park. Late summer and early autumn marks the best time to visit as its high elevation – almost 8200 feet at the trailhead – means it’ll be covered in snow for several months; sometimes the trail doesn’t open until the Fourth of July.

To reach the trailhead, from Interstate 5 in Redding, take Calif. Hwy. 44 east into the park. Turn right/south onto Calif. Hwy. 44. In about 20 miles, you’ll pass Helen Lake. Look for the parking lot on the road’s left/south side. The trailhead is at the oval lot’s northeast corner.

Initially the tail parallels the road but then veers southeast as heading toward the hydrothermal features that make up Bumpass Hell. You’ll immediately notice in the distance multiple columns of steam rising from a basin that’s variably orange, yellow, green and brown. You’ll also instantly notice the smell of sulphur, which is akin to the scent of rotten eggs.

Rim of ancient volcano
The trail rises and dips repeatedly in largely open country, still dotted with snow and ice, for the first 0.9 miles, where you’ll reach the highest point, an overlook of the basin at 8400 feet above sea level. This is the rim of ancient Brokeoff Volcano, which today is known as Mount Tehama.

Over the next third of a mile, the trail descends about 200 feet into the basin, where it becomes a boardwalk that guides you through 16 acres of the park’s largest concentration of hydrothermal features. It includes a short spur that takes you almost to Bumpass’ center. A ring of tall evergreens line the Bumpass’ northeast side.

From 600,000 to 400,000 years ago, Mount Tehama towered some 11,000 feet high. A classic stratovolcano, volcanic explosions and glaciers have sheared off its top.

Bumpass Hell actually is a side vent of the volcano. As rain and snow falls on nearby Lassen Peak and seeps into the ground, a pool of hot, molten rock deep in the volcano boils it into steam. That vapor condenses as rising toward the surface and escapes into the air at the mudpots, fumaroles and hot springs at Bumpass.

Big Boiler
Among Bumpass’ most impressive features is the Big Boiler, which shoots high-velocity steam into the sky. It’s the park’s largest fumarole in the park and is one of the world’s hottest fumaroles at 322°F.

Because of the boiling water and its acidity, do not leave the boardwalk trail. Indeed, the area is named for an early settler who fell into a boiling pool and severely burned his leg.

You’ll want good hiking boots as the trail leading to the boardwalk will be rocky. In addition, with high altitude and little tree cover, be sure to wear sunscreen to avoid sunburn.

Once the boardwalk trail dead ends, return the way you came. Pace yourself on the steep walk up the caldera to the overlook; there really is less oxygen at this high elevation, and you easily can lose your breath if not suffer from altitude sickness.

Learn more about national park day hiking trails in my Best Sights to See at America’s National Parks guidebook.