On the northern slope of Mount Tamalpais just past Fairfax is a series of sparkling lakes perfect for hiking and fishing. The lakes are actually reservoirs, part of the Marin Municipal Water District, supplying water to Marin County residences. Bon Tempe Lake, the widest of the watershed lakes, is home to an abundance of birds, animals and spring wildflowers.
The two main trails around Bon Tempe are Shadyside, circling the west side of the lake, and Sunnyside, circling the east. Connecting the two trails is the Bon Tempe dam, which offers spectacular views. Pack a picnic lunch and lots of water when you go.
The complete circuit around the lake is about 4 miles. Bikes are not permitted.
From the Lake Lagunitas picnic area, walk past the picnic tables and cross a wooden bridge. Turn right to get on the Shadyside trail. The trail is a gentle dirt path with a few tree roots, rocks and some steps. Although shady, it’s not dark, with vistas of Bon Tempe Lake opening up frequently and patches of sunlight streaming through the trees.
Spring wildflowers and ferns line the trail. You may see trillium, milkmaid, iris and even some orchids. Above are black oak with their large, deeply lobed leaves, coast redwood, bay and pine. Picturesque wooden bridges and a little beach complete the scene. After about a mile and a half, you arrive at the dam.
The Bon Tempe dam
Built in 1948, the Bon Tempe dam is one of four dams on the upper 8 miles of Lagunitas Creek. As you cross the massive earthen dam, you will be walking between Alpine and Bon Tempe lakes with impressive views of both, as well as of Mount Tamalpais. There is a small parking area here (but no facilities except for a pit toilet).
If the water isn’t too high, you can circle right around to the Sunnyside trail. In wetter years than this one, you would have to take the trail past the parking area to connect to Sunnyside. Just as Shadyside isn’t all shady, Sunnyside isn’t totally sunny. You will find some welcome canopy here. The lake is stocked with fingerling rainbow trout, and people fish from the shore for both trout and bass. (No boats are permitted.) Many birds – cormorants, egrets, heron and osprey – are busy fishing as well.
The Sunnyside trail meets with Sky Oaks Road. Continue on the road until you see a trail cutting back down to the water. This is Pine Point trail, which allows you to get very close to the lake and scramble down to little beaches while enjoying the shade of some huge Douglas fir. Paths head off in various directions, but just stay close to the lake for the best views.
You will come to a dirt road that leads back to the Lake Lagunitas picnic area and parking lot. The large set of valves that you pass sends lake water to a gravity-fed treatment plant. Pick out a shady table and enjoy a picnic lunch.
After the walk
If the Sunnyside trail got you in a sweat, cool off with a scoop of organic ice cream in Fairfax at Fairfax Scoop (63 Broadway Blvd.).
From San Francisco by car, take Highway 101 to the Sir Francis Drake Boulevard exit and go for about 6 miles into Fairfax. Turn left on Pastori Avenue (or, if you miss it, on Pacheco Avenue). Turn right immediately on Broadway/Center Boulevard and then left onto Bolinas Road. After about 1.4 miles, turn left on Sky Oaks Road. You will shortly come to an entrance kiosk. The day use fee is $8, which you can pay by credit card. When you come to a fork, turn left toward Lake Lagunitas. Continue to the Lake Lagunitas picnic area and park.
Urban Outings are presented by Greenbelt Alliance, the Bay Area’s advocate for protecting open spaces and creating vibrant places. To suggest an Urban Outing, contact Gail Todd, tour leader for S.F. City Guides and author of “Lunchtime Walks in Downtown San Francisco.” To find out more about Greenbelt Alliance’s work, visit www.greenbelt.org.