Lake Eileen, 8,880', from Vallecito Reservoir

Essence: The Lake Eileen Trail is a relatively short, well-graded, flowerful dirt footpath winding up through a woodland regenerating after the 2002 Missionary Ridge Fire. "Eileen's Pond" is but one of a few lakes in the Weminuche Wilderness whose shallows are conducive to supporting pond lilies. Deep green, heart-shaped leaves and spherical yellow flowers float on the periphery of the central blue disk. Enjoy dreamy and ethereal lakeside moments sitting on a large boulder shaded by an aspen grove. Locals favor this nature walk during the golden hues of autumn. The hike is within the Weminuche Wilderness managed by the San Juan National Forest.

Travel: The trailhead is located just north of Vallecito Reservoir. Driving north on CR 501, the road splits below the dam. Curve left, staying on CR 501, and measure distance from there. Drive north on the west side of the lake. At 5.0 miles, the Vallecito Work Center, San Juan National Forest, will be on your right. Immediately watch for a large, dirt pullout on the east side of the road and park. If you reach the junction with CR 500, you've gone too far. The posted trailhead is on the west side of the road. No facilities, no water. 

Distance and Elevation Gain: 4.2 miles; 1,160 feet
Total Time: 2:30 to 4:00
Difficulty: Class 1 maintained trail; navigation easy; no exposure
Map: Vallecito Reservoir, Colorado 7.5' USGS Quad 

Date Hiked: May 29, 2026
Poem:  

The morning sun
shines on the flower.
Each time I see
the jewel shape
joy increases. Enku
 

A hiker blends with successive shades of green rings--pond lilies, spongy grasses, and aspen. Painter Wassily Kandinsky wrote, "Absolute green is the most restful color." (Thomas Holt Ward, photo) 

Route: Lake Eileen Trail #899 bears northwest to trail's end at the lake. Return as you came. See the note below about circumnavigating the lake.

 

The Lake Eileen Trailhead, elevation 7,740', is located on the west side of CR 501. The county highway carries fast-moving traffic so be cautious crossing the blacktop. Firefighters were able to preserve a thin strip of ponderosa and Douglas fir. 

 

Lake Eileen is proximal to the southern boundary of the 499,771-acre Weminuche Wilderness. Designated by Congress in 1975, it is the largest wilderness area in Colorado. 

  

Please sign the trail register at 0.1 mile. The trail sees consistent use but on our hike solitude was complete. Emerge from heavy timber onto an open hillside incinerated in the 73,000-acre Missionary Ridge Fire. Sporadic conifers are standing but the understory is dominated by opportunistic post-fire aspen and Gamble oak. In May, they were cloaked in iridescent spring green. 

The American West is suffering from an ongoing drought. The 2025-2026 winter was especially dry. I recorded a fair number of flowering plants but none were prolific. Growing on the sunny lower slope was mountain parsley, pussytoe, serviceberry, whiplash daisy, mahonia, potentilla, and chokecherry, shown. Ubiquitous mountain-lover, distinctive for its tiny blossoms and opposing leaves was holding the ground down. (THW, photo) 

With the slightest breeze aspen leaves tremble and flutter in a silent dance routine. Snowberry is commonly found under their canopy. This dominant shrub grows three to five feet tall. Tiny pink blossoms in early summer are followed by white berries which are especially striking after the leaves drop. Do not be tempted to take a taste. The berries are toxic to both animals and humans. 

The pink to brick-red boulders scattered across the landscape on the western side of the Vallecito Creek Basin are Eolus Granite. The coarse-grained, intrusive igneous rock was emplaced 1.4 billion years ago. They cover about 100 square miles in the southern Needle Mountains between Vallecito Creek and the Animas River. The color is distinctive on Mount Eolus where it was first named by geologists in 1905.

Cross Lost Creek at 0.4 mile on sturdy stones. The stream gathers water from the highpoint of West Mountain, 11,831'. It is a west tributary of Vallecito Creek, a fork of the Los Pinos River which drains into the San Juan River in the Colorado River Basin. 

 

In the deep wood we saw heart leaf arnica, native honeysuckle (twinberry), white violet, and streamside mountain ash, shown. In the fall, mountain ash is prized for its bright red leaves and berries. (THW, photo)  

Immediately after the crossing, enter the Weminuche Wilderness. We spotted a single salsify. This plant is a non-native species, introduced to America by Europe and Asia because it is edible. It is technically classified as a weed but it is infrequent and does not crowd native species. Seedheads look like overgrown mutant dandelions. (THW, photo)  

The saturated color of the wood's rose this year was screaming brilliant. Put your nose inside the blossom for an altered state of consciousness. (THW, photo)  

The dirt track ascends gently with periodic flat reprieves. Switchbacks were constructed with big boulders. There's something extra sweet about the smooth turns and easy, consistent grade. It's never too steep. The many-flowered puccoon (pretty stoneseed) was a new species for us. (THW, photo)  

This image overlooks Vallecito Reservoir. Trees were cleared for the lake by the Civilian Conservation Corps and the earthen dam was constructed in 1940 by the U.S.  Bureau of Reclamation. It is 162 feet high and 4,010 feet long. It impounds both Vallecito Creek and the Los Pinos River for flood control and irrigation.  

From the same location, Sheep Mountain with snow cornices on its crown is beyond the far north end of Endlich Mesa. The high peaks toward image-right are in the Needle Mountains. 

 

A sandstone platform overlooking the Vallecito Creek Basin is 1.1 miles into the hike. Not far beyond, weathered limestone boulders are prevalent. Ouray Limestone of Devonian age (419 to 359 million years ago), was discovered by F. M. Endlich in 1875. This rock layer is widely exposed across the San Juan Mountains and southwestern Colorado. Endlich Mesa (Crevasse and Sheridan Mountain) is a premier landscape and I'm delighted to learn it was named for this geologist.  

Lupine invites those who dare to climb its purple ladder into the harmonic heavens. For Kandinsky, the color purple was a deeply spiritual "chord struck between the calm of blue and the fire of red." (THW, photo)   

The trail levels off just before arriving at the lake at 2.1 miles, elevation 8,880 feet. My first impression was, wow, that's trippy. The lake rests in a very large, flat-bottomed bowl. Both the inlet and outlet were barely trickling in May, 2026. Elements fan out in concentric circles from the watery center. A ring of pond lilies encircles the shoreline, unbroken for 360 degrees. Next, is a mix of boggy grasses, sedges, rushes, cattails, and a mossy floor saturated with crawling insects. On the outer periphery are young aspen trees. Above it all was a cacophony of bird song. Look for a makeshift path lined with logs to help you get to water's edge without getting your feet soaked. A picnic boulder seems odd in its singularity. But where are the frogs? If I was a frog, I'd live here. 

Perhaps the most distinguishing characteristic of Lake Eileen are the pond lilies. I know of only one other lake in the entire region with them. Waterlilies have strict requirements to flourish, and Eileen's Pond is entirely suitable. They require clear, shallow water, typically less than six feet deep. They favor slow-moving waters where the sun easily warms the shallows, top to bottom. Plus, there has to be enough sunlight for plants to photosynthesize. And finally, the bottom sediment must be soft, nutrient-rich muck so they can anchor their extensive root systems. No invasive species allowed! (THW, photo) 

 

I would gladly repeat this hike time and again for the sole purpose of gazing into a Great Yellow Pond Lily. This blossom is being visited by a Western honey bee. The flowers are three inches across with thick sepals. It is the only native species of waterlily in the Western U.S. (THW, photo) 

We circumnavigated the lake. That's what people do (right?) who want to understand a body of water. We headed north on a promising social trail. It soon ended and we stepped on spongy, dried up grass.  

The fire had roared through, sparing some trees, scorching others. Almost a quarter century post-fire, the forest was reduced to pickup sticks which we dutifully stepped and climbed over. Bottom line: circling the lake isn't for everyone.

Enku, Japanese monk, sculptor, and poet, carved 120,000 wooden Buddhas in his lifetime (1632-1695).  He found joy gazing upon flowers (poem at the top). Whether it be granitic boulders, aspen trees, or wildflowers, may you find joy on your simple walk to Eileen's Pond.