Basic Facts, the Lay of the Land.
Hiking South from the Southern Sharkfin (peak 9501) on the Southern side of Murray Canyon we begin circling around the Southwest side of Boulder Peak, swinging into and climbing out of Westward drainages for the first time since our brief descent from Tyron Peak.
Hiking South from Wolf Creek Pass we have been following along the Eastern side of the Sierra crestline capped by Arnot and Disaster Peaks to our Southwest. South of Disaster Peak we briefly cross over to the Western flank of the Sierra as we circle around the Southwest side Boulder Peak.
Two Rivers, Two Trails
After circling all the way around to the Southeast side of Boulder Peak we find ourselves perched on a narrow sliver of forested ridge crest dividing and overlooking both the Eastern and Western drainages off of the Sierra Crest. This narrow neck divides the two great rivers draining this section of the Eastern and Western Sierra, the East Carson River to the East from the Western Flow of the Clarks Fork of the Stanislaus, and therefore this ridge also divides the two great trails that follow these rivers, the PCT and TYT.
The Tahoe to Yosemite Trail passes 2.74 miles below us to the Southwest via the Boulder Lake trail. We are standing at the closest point that these the PCT and TYT pass to each other along the trail. At Highway 108 the Pacific Crest Trail Trailheads at Sonora Pass are one mile East from the Northbound Tahoe to Yosemite Trail Trailhead at Saint Marys Pass.
Boulder Lake is the closest point between the PCT and TYT along the trails themselves from the Lake Tahoe Basin, where these routes divided, to where their routes rejoin below Bond Pass in Jack Main Canyon.
East and West Flanks
The drainage from the East sides of Arnot, Disaster and Boulder Peaks feed the East Carson River. The Western-sides of this line of peaks feed Disaster Creek and Boulder Creek via Boulder Lake, both of which contribute to the Clarks Fork of the Stanislaus.
This particular little piece of crestline is special because it is one of the rare places where we can actually stand between these Eastern and Western drainages. We are usually hiking along the East or the West flank for many miles. The Pacific Crest Trail route North from Dorothy Lake Pass to Carson Pass can be characterized by its Eastern flank route compared with the Western flank route of the Tahoe to Yosemite Trail.
Here at Boulder Peak to the Boulder Lake trail junction the PCT peeks into both the East and West drainages.
Hiking the PCT North and South of Boulder Peak we will again be decidedly on the Eastern Flank of the Sierra. South of Boulder Peak we will be deep within the drainage of the East Carson River. Southbound hikers will remain on the Eastern flank of the Sierra, with a few notable exceptions, until we enter Yosemite National Park through Dorothy Lake Pass and enter the Western Drainages of the Toulumne River. Northbound hikers along the PCT will also be hiking along the Eastern flank of the Sierra up to the Lake Tahoe Basin, again with a couple of notable exceptions (Tyron Peak, The Nipple above Blue Lakes, and the top of the North Fork of the Mokelumne River drainage at Carson Pass), until you enter the Lake Tahoe Basin.
Continuing South on the Tahoe to Yosemite Trail from the Boulder Lake trail junction the Pacific Crest Trail brings us switch-backing down to the East Carson River. Dropping down to the East Carson river the Sierra crestline dividing us from the Clarks Fork now sits above us to our East, capped by Stanislaus and Sonora Peaks running North to South. Sonora Peak's Northeastern flank composes the Western side of the East Carson River's headwaters bowl. Climbing out of the East Carson River's headwaters bowl we will traverse around Sonora Peak's Eastern and Southern flanks to finally access Sonora Pass.
This little neck of ridge that separates the great Carson and Stanislaus rivers is also special because it allows us to craft great backpacking loops through the magnificent upper reaches of both the East Carson and Clarks Fork rivers. The Boulder Lake trail linking these Eastern and Western drainages gives us easy access to the stunning high country up to and around the headwaters of both the Clarks Fork and the East Carson Rivers without having to hike too many miles.
The loop from Sonora Pass North along the Pacific Crest Trail to the Boulder Lake junction then through the Boulder Lake trail down to the Tahoe to Yosemite Trail along the Clarks Fork and South up to the Clarks Fork Trailhead on Highway 108 is 23.52 miles. If you hike variations of this loop out of the Clarks Fork Road trailheads you can pump up the miles by enlarging the loop.
The Carson Iceberg topo hiking map is decorated with these loops
Continuing our Hike South along the Pacific Crest Trail
We have one more high ridge line and one more high drainage to cross South of the Boulder Lake trail junction before we pass around the West side of "the plug," the massive granite formation that pinches the course of East Carson River twelve hundred feet below.
Passing around to the South side of "the plug" we begin switch-backing down to the East Carson River. The USGS 7.5 topo map quadrangle appears to be inaccurate here. The bulk of the switchbacks down to the river from the crest line appears to be situated further South of The Plug, AKA Peak 9065, and the trail itself down to the East Fork of the Carson River now switchbacks down crossing this creek multiple times, rather than being composed of a couple of big traverses winding their way down-mountain North of this small drainage cascading down the mountain flank, as depicted on the USGS Disaster Peak quad.
Currently (2010) the switchbacks are centered on this steep creek tumbling down the canyon-side.
Either the trail or the creek has moved since the maps were drawn.
Once at the bottom of the switchbacks the Pacific Crest Trail becomes a a gentle track on gently rolling terrain Southbound through dense swaths of spreading Aspens shortly bringing you to the unmaintained East Carson Trail junction on the Southbound hiker's Left.
The East Carson River Trail turns North here to follow the East Carson River downstream to Carson Falls. Just South of Carson Falls you will find the Golden Canyon Trail leading West up to the PCT and North of Carson Falls the Murray Canyon Trail tracks West to join the PCT. These junctions also offer options for hiking loops, but these loops incorporate the difficulties of the unmaintained trail section between the East Carson River trail junction on the PCT to Carson Falls, a difficult section.
Hiking South along the PCT we cross a small stream a few feet North of the East Carson trail junction, which provides water for the uneven campsite on the West side of the PCT across from the trail junction.
I am one of the people who yearly duck the PCT East Carson junction when I can first get through the route as the snows recede, but I do not duck the E Carson Trail itself. Injury has knocked me out of the Spring opening of this rough trail in 2011 and likely 2012. Nonetheless this well-worn trail junction is easy to spot.
A much superior campsite overlooking the East Carson River than the uneven site along the trail sits about a hundred yards down the East Carson River Trail.
At 8160 feet the Pacific Crest Trail junction with the East Carson trail is the lowest point of our hike through the East Carson River drainage. Hiking either North or South from this point offers significant climbs. North up the switchbacks to the Sierra Crest line, and South up through the steady climb up to through the headwaters of the East Carson to the high Gap on the Southeast flank of Sonora Peak above Sonora Pass. The climbs in either direction make the East Carson River trail junction an excellent break spot.
South from the Pacific Crest Trail junction with the East Carson River Trail we face a 5.86 mile ascent up 2376 feet of elevation to the Sonora Gap at 10,500 feet, our highpoint on this section of the trail. Another 2.88 miles South from the Sonora Gap brings us down into Sonora Pass at 9624 feet and road access on Highway 108 down to our next resupply spot at Kennedy Meadows Pack Station.
The East Carson River trail junction to Sonora Pass: 8.74 miles