Ron Horii's Bay Area Back Pages - Bay Area Biking
Crystal Springs Trails

Aerial view of Crystal Springs valley
Aerial view of Crystal Springs watershed (Flight Unlimited II screen shot)

Locked in the heart of the San Francisco Peninsula is a precious jewel: the Crystal Springs watershed. It's like the Hope Diamond - a beautiful national treasure that you can see, but can't touch. Until recently (see below), most of these 23,000 acres of wild and pristine lands were off-limits to all but authorized personnel. Unless you had special authorization, the only way to see all of the Crystal Springs watershed was from the air. The above is a screen shot from the Flight Unlimited II flight simulator looking south at part of the watershed. San Andreas Dam is at the lower left. Interstate 280 runs along the left edge. Lower Crystal Springs Reservoir is at the upper left. Pilarcitos Lake, which cannot be easily seen from any publicly-accessible vantage point on land, is at the upper right. Sawyer Ridge runs from the lower right to the upper left. The Sawyer Camp Trail runs along the eastern base of Sawyer Ridge from the east shore of Crystal Springs Reservoir to San Andreas Dam. Notice the total lack of development in the area, except for the fire and maintenance roads. Before 2003, the only publicly-accessible areas in the picture above were Hwy 280, the Sawyer Camp Trail, and a few areas to the left of San Andreas and Crystal Springs reservoirs. The San Andreas fault can be seen running in a line down the middle of Crystal Springs to San Andreas reservoirs.

These are truly wild lands. This has been a state wildlife refuge since the 1930's, so hunting and fishing are prohibited. The San Francisco Water Department jealously guarded their treasured lands, refusing to let anyone else step on them for fear of damaging the watershed and compromising the purity of their water supply. In the process, they preserved the natural beauty and wildlife of the area. More animal species are found here than anywhere else on the peninsula. The reservoirs here are rumored to be teeming with enormous fish. Fisherman look on covetously on these unfished waters, dreaming of the monsters that must be lurking in their depths. (Don't even think of trying to fish here. It's illegal to even have fishing gear in your possession in the area.) Though you can't actually enter the wildlands here, you see them and come close to them from the roads and trails that pass along the east edge of the area.

Interstate 280 north of Cupertino is dubbed, "The World's Most Beautiful Freeway." Not that it has much competition, but the reason it can call itself that is that it runs through one of the most beautiful regions of the Bay Area - the San Andreas Rift Valley and the San Francisco Watershed. The San Andreas Fault runs through the heart of this valley and created it. Two long, slender reservoirs are in this area - Crystal Springs Reservoir and San Andreas Lake - and are visible from the roads here. San Andreas Lake is what gave the name to the fault, not the other way around. The fault runs right down the center of each of the reservoirs. I-280 is fast, 10-lane wide in places, and runs high above, east, and parallel to the fault.

This area has a long history. Long before the white man arrived, the Costanoan Indians inhabited this area for centuries. 1769, Captain Gaspar de Portola, governor of Baja California, led an expedition to explore Alta (upper) California. While searching for Monterey Bay, Portola's scouts made a surprising discovery. They climbed what is now Sweeney Ridge and discovered San Francisco Bay. Instead of being awed or elated about the sight of the enormous and beautiful bay stretching before them, the hungry and lost explorers were disappointed. They had not found their objective, Monterey Bay, and dejectedly turned back south. A few years later, the Portola party again explored this area, looking for a site for a mission and presidio. On November 30, 1774, the feast day of San Andres, Father Francisco Palou, who was Portola's diarist and historian, traveled through this valley and named it San Andres, to honor the saint's day. This is how the San Andreas Valley got its name, which later became the name of the reservoir here and the famous fault line.

In the 19th century, there were small farms and dairies in the region. During the Gold Rush era, the small town of San Francisco became a booming city. Recognizing the need to supply water for the growing city, the Spring Valley Water Company of San Francisco, headed by William Bourn, began buying up farms in the San Andreas valley to acquire the watershed. 

As the city's water needs grew, the company built dams to create Pilarcitos Lake, San Andreas Lake, and Upper and Lower Crystal Springs Reservoir. Eventually, even these were not enough. The local watershed could not collect enough water for the city's needs. It began looking towards the water-rich high Sierras.  In 1902, it petitioned the Department of the Interior for rights to water in Yosemite's Hetch Hetchy Valley. In 1908, the U.S. House of Representatives passed a resolution, introduced by San Francisco Representative Julius Kahn to build a reservoir in Hetch Hetchy Valley and bring water to San Francisco. This infuriated conservationists, particularly Sierra Club president John Muir, who spoke and wrote vehemently against the plan. Hetch Hetchy Valley was nearly a twin of the renowned Yosemite Valley, and Muir considered damming it a sacrilege. Nevertheless, in 1913, the Raker Act was passed, granting San Francisco the right to dam the Tuolumne River in Hetch Hetchy Valley. The O-Shaughnessy dam was built across Hetch Hetchy Valley, and a 150-mile long system of pipes and tunnels brought water to the Bay Area, eventually delivering the water to Crystal Springs Reservoir. The Hetch Hetchy water is of such high quality that it doesn't require filtering. It is the largest unfiltered water supply on the West Coast. It gives San Francisco some of the best-tasting water of any metropolitan area in the country.  However, it makes the water supply vulnerable to contamination from human contact with the waters and from erosion caused by damage to the watershed. That's why access to the watershed lands are so severely restricted.

To get a closer, more intimate view of the area, you can take Canada Road, Skyline Blvd., and the Sawyer Camp Trail. These run closer to the San Andreas Fault, mostly west of I-280. Canada Road runs from Woodside Road in Woodside, all the way to Hwy 92. Hwy 92 continues west, crossing over the causeway dividing Upper and Lower Crystal Springs Reservoirs. The road climbs up and over the Santa Cruz Mountains at Crystal Springs Gap to drop down to Half Moon Bay. In the summer, coastal fog pours through this gap, providing welcome cooling to the sunny valley. Skyline Blvd. runs south from Hwy 92 along the crest of the Santa Cruz Mountains. Skyline Blvd. runs north from Hwy 92, continuing along the east shore of Crystal Springs Reservoir for a ways before crossing under I-280 at Hayne Road and continuing on east of I-280. Skyline Blvd. and I-280 then run together for awhile along San Andreas Lake before splitting apart halfway up the lake. Skyline Blvd. continues straight north, following the San Andreas Lake shoreline and the San Andreas Fault. It ends at Lake Merced in San Francisco. These are two-lane roads open to automobile traffic, with bike lanes along the sides.

A section of Canada Road from Hwy 92 to Edgewood Road in Woodside is closed to automobiles on Sundays from 9 am to 4 pm, weather-permitting. The wide road then becomes a highway for bicyclists, skaters, and pedestrians. At Edgewood Road, the route starts near the southern entrance to the Filoli National Historic Site. Even though the site's 36,000 square foot mansion and the 17-acre gardens are not visible from the road, millions of people have seen them. They were featured in the Warren Beatty movie, Heaven Can Wait. The mansion served as the Carrington mansion in the nighttime soap opera, Dynasty. Filoli actually was built by William Bourn, the gold baron who owned the Empire Mine in Grass Valley. He later became president of the Spring Valley Water Company, which supplied water to San Francisco and built the reservoirs in the area. The house and gardens and the 654-acre estate now belong to the National Trust for Historic Preservation. You can tour the mansion and gardens, but reservations are required.

Pulgas Water Temple Closeup of Pulgas Water Temple
Pulgas Water Temple grounds Pulgas Water Temple columns

A little farther north is a surprising sight among the dry grass and oaks of the valley - a lush green lawn, tree-shaded gardens, a formal reflecting pond rimmed by stately Italian cypresses, and a Roman temple at the end. It looks like a setting from Disney's Fantasia. This is actually the Pulgas Water Temple, which was built in 1938. The "temple" is the terminus and outlet for the aqueduct carrying water to the region from Yosemite's Hetch Hetchy Reservoir. Thrill-seeking teens used to jump into the wide drain basin inside the temple. The water shoots out and down into an open canal west of the temple and ends up flowing into Upper Crystal Springs Reservoir. A grate over the basin prevents access to the water, but also makes it difficult to see it. The shady green lawns and drinking fountains form a welcome rest stop. This spot used to be a popular and noisy hang-out for teenagers on weekends. Now, the parking lot is only open during weekdays from 9 to 4, so it's much quieter now.

House on Crystal Springs, looking NW Crystal Springs Reservoir, house on shore
House on shore of Crystal Springs Reservoir, seen from Canada Road Crystal Springs Reservoir, looking south from Canada Road

Farther north, the shores of Upper Crystal Springs Reservoir come into view. The road follows along the rocky east shore. A large house appears on a point on the shoreline. I don't know whose house that is or was or who lives in it now, but it's in one of the most spectacularly scenic locations in the Bay Area. I hope they have an "open house" someday.

Canada Road
Canada Road by Crystal Springs Reservoir on Bicycle Sunday

Canada Road, when it's closed to traffic, is great for bicyclists to ride fast. Though the area is hilly, the road runs fairly flat and straight through road cuts, with gradual ups and downs. Unlike the nearby paved multi-use trails, which have 15 mph speed limits, you can ride as fast as you want on Canada Road, and it's wide enough to avoid pedestrians. On the portion of the road near Hwy 92, the bike lanes are as wide as the car lanes.

If you want a more natural experience, you can hike the Crystal Springs Trail. This narrow dirt trail (no bikes or dogs allowed) runs along the west edge of Canada Road from Hwy 92 to past Edgewood Road until Canada Road crosses under I-280. However, it has much more ups and downs than Canada Road. Instead of going through the road cuts, it goes up over the hills and down into the gullies along the way. The trail runs through the hills west of I-280, then turns west at Raymundo Drive. It climbs into the steep Santa Cruz Mountains, runs through wooded Huddart Park, then ends at the summit of the mountains at Skyline Blvd.

Start of the Sawyer Camp Trail
Start of the Sawyer Camp Trail, next to Crystal Springs Reservoir

The Sawyer Camp Trail is a 6-mile long paved multi-use trail, closed to automobile traffic, that runs along the Shoreline of Lower Crystal Springs Reservoir to San Andreas Lake. It's the most popular trail in the San Mateo County Park system, and for good reason. It's an easily-reached, incredibly scenic trail that takes you closer to forbidden Crystal Springs Reservoir and San Andreas Lake than any other trail. It follows the path of the old wagon trail that was the main travel route between Half Moon Bay and San Francisco. You can get to the southern entrance by taking the Bunker Hill exit from I-280, head west, then turn right on Skyline Blvd. Drive over Crystal Springs Dam and look for a parking spot.

Bridge over San Mateo Creek, I-280
I-280 bridge over San Mateo Creek from Crystal Springs Dam

The trail begins north of Crystal Springs Dam at the intersection of Skyline Blvd. and Crystal Springs Road. There are parking areas north of the dam that fill up fast. You can also park along the road south of the dam. Crystal Springs Dam is an engineering marvel. Built out of interlocking reinforced concrete blocks in 1890, it was the largest concrete dam in the world at the time. It was built so strong that the Great San Francisco Earthquake of 1906, which occurred on the San Andreas Fault, didn't damage the structure, even though the fault is only 100 yards west of the dam. From the dam, you can see large bass swimming around in the reservoir. They're just a hint of the huge monsters that must be lurking in these unfished waters. The other side of the dam overlooks the canyon of San Mateo Creek. The towering I-280 bridge spans the steep canyon high above the canyon floor. On the north side of the canyon is the wealthy community of Hillsborough. Perched along the hillsides are multi-million dollar homes, including the famous "Flintstone House," that looks like it's made of mud domes.

Deer on Sawyer Camp Trail Crystal Springs Reservoir
Deer along Sawyer Camp Trail Crystal Springs Reservoir

The first part of the trail is mostly sunny, running along the shore of Crystal Springs Reservoir. There are a few shady spots as the trail dips into ravines. The surrounding hills are mostly grass-covered. The inviting waters of Crystal Springs are constantly in view, but the fence prevents access. Wildlife thrives in this fish and game refuge. Deer can be seen grazing in the grassy areas or even along the trail.

Marsh north of Crystal Springs Reservoir
Marsh with deer north of Crystal Springs Reservoir

For most of the way along Crystal Springs Reservoir, the trail runs below the Crystal Springs Golf Course. At the northern end of the lake is a small dam. The dam creates a pond that dries up in the summer. The marsh that forms here is a prime deer grazing spot.

Jepson Laurel Rest stop near Jepson Laurel
Jepson Laurel Rest area, Sawyer Camp Trail

As the trail leaves Crystal Springs Reservoir, it enters a more heavily forested section. At a rest stop is the Jepson Laurel, the largest and oldest known bay laurel tree in California. A fence around the huge 600 year-old tree prevents people from trampling its root area. The rest stop also has drinking water, restrooms, and picnic tables. There are interpretive displays describing the history of the Crystal Springs water system and the Sawyer Camp Trail. Sawyer Camp is named after Leander Sawyer, who had a camp here in the late 1800's. He provided food and lodging to travelers on the trail between Half Moon Bay and San Francisco. He also raised cattle and trained circus horses in the valley.

Shady lane on Sawyer Camp Trail
Shady Lane on Sawyer Camp Trail

After the Jepson Laurel rest stop, the trail continues through a cool, shady canyon. The forest becomes denser, and trees arch over the trail, forming a living tunnel, and ferns grow along the hillsides. The steep sides of Sawyer Ridge border the trail to the west. After climbing and dipping, the trail begins the long steady climb up the hillside to reach San Andreas Dam. The trail makes a few loops around corners. Watch out for pedestrians and speeding downhill bicyclists here.

San Andreas Dam
Dam at San Andreas Lake, Sawyer Camp Trail

At the west end of San Andreas Dam is a rest stop under the trees. The trail crosses over the dam. You can see the dry, wooded valley below the dam. San Andreas Lake stretches north. Its off-limits west shore is densely forested. After crossing the dam, the trail continues north along the east bank of the lake, gradually climbing. It passes by some steep rocky cliffs that are the remains of a rock quarry. The trail levels off and passes by a Caltrans station, where there's a drinking fountain. It then drops down to its northern entrance, the only other access point to the trail, at Hillcrest Blvd, where it just crosses under I-280. There is a trail that continues north along the east shore of San Andreas Lake, but is presently closed to bicycles. Also at this point is a large boulder with an historical plaque commemorating the nearby spot where Captain Gaspar de Portola's party, the first Europeans to discover San Francisco Bay in 1769, camped near a lagoon now covered by San Andreas Lake. The site where Portola's party first spotted San Francisco Bay is located in a finger of the Golden Gate National Recreation Area high on Sweeney Ridge, northwest of San Andreas Lake. A trail leading to it starts from the end of Sneath Lane in San Bruno.

San Andreas Dam, Lake, and ridge to west
San Andreas Lake, Dam, and Sawyer Ridge to the west

If you don't feel like riding on frontage roads near the interstate or through the suburbs, the best way back is to return on the Sawyer Camp Trail. Watch your speed on the downhill below San Andreas Dam or you may get in an accident or get cited. If you continue along Skyline Blvd. south of Crystal Springs Dam, you'll follow the road along the side of Lower Crystal Springs Reservoir. If you cross over Hwy 92, you can follow Canada Road south along Upper Crystal Springs Reservoir to Woodside.

2003 Update:

The long-closed Crystal Springs Watershed was finally opened to the public in 2003. After much discussion and controversy, the San Francisco PUC opened up a section of the watershed to access, but only on a restricted basis. You must make a reservation for a docent-guided tour. The 10-mile trail runs along a fire road that starts at Hwy 92 and ends at Sweeney Ridge. (See map.) For more details, see the official website: SFWATER.ORG: Fifield-Cahill Ridge Trail at the San Francisco Peninsula Watershed.  Here are some links about this trail opening:


Here are some more links on the Crystal Springs area and nearby trails:

Links on the San Andreas Fault:

Click here to return to my Bay Area Biking Page
Click here to return to my Bay Area Back Pages Home Page

Ron Horii, San Jose
Created 11/27/98, updated 10/1/03