Bay Trail Route West to Lockheed Martin
Bay Trail Route East to Alviso
Go to Part 2 - The Baylands Ponds
Go to Part 3 - Sunnyvale Baylands Park and Nearby Trails
Go to the Mountain View - Stevens Creek Trail Tour
Go to the Alviso Tour
Return to the Bay Trail Guided Photo Tours page
The Sunnyvale Baylands are at the southwest corner of San Francisco Bay between Mountain View's Moffett Field and the San Jose community of Alviso. The Baylands consist of sewage treatment ponds, salt ponds, drainage channels, and active and retired landfills. This does sound not very appealing, but the area has many attractions for those who can overlook its less glamorous features. It is one of the best places in the Bay Area for bird-watching. The water treatment ponds and levees are covered with huge flocks of water birds. Egrets and herons nest in the vegetation along the sloughs and channels and wade in the marshes here. Flotillas of giant pelicans cruise the ponds for food. The upland hills are homes for burrowing owls, songbirds, and raptors. There are miles of uncrowded levee trails around the ponds, sloughs, and over the landfills. The landfill hills provide panoramic views of the South Bay and Silicon Valley. At the east end of the Sunnyvale Baylands is the developed Sunnyvale Baylands Park, a diverse recreation area which will be covered in Part 3.
The official Bay Trail route through the Sunnyvale Baylands is a relatively short, straight trail, running for less than 4 miles, but it connects to miles of side trails and several recreation areas. (Here is the Bay Trail map.) Although the trails here never quite reach the open waters of the Bay, they run along ponds, sloughs, creeks, and channels that directly or indirectly connect to the Bay. Trails run along dirt levees roads, gravel service roads, and paved bike paths. Many trails are still under construction, but are accessible to the public. New trails are being proposed.
Most of the Bay Trail route through the Sunnyvale Baylands was dedicated on July 1, 1999. The newest 1-mile extension west next to Lockheed Martin was dedicated on June 5, 2001. The Bay Trail route through Sunnyvale starts in the west at the edge of Lockheed Martin Property next to the Moffett Field boundary. It heads east below a series of retired landfill hills. It then passes between the Sunnyvale Water Pollution Control Plant and its water treatment ponds. Next, it runs by the Twin Creeks Sports Complex and Sunnyvale's Baylands Park. It then begins to parallel the Guadalupe Slough. It passes by a large saltwater pond that serves as a bird refuge. It reaches the banks of Calabazas Creek and turns inland. It then follows along a wide paved former road paralleling Hwy 237. It crosses Calabazas Creek and San Tomas Aquino Creek. Trails along these creeks will be covered in Part 3. The Bay Trail ends at Great America Parkway near the community of Alviso.
Some of the side trails at the Sunnyvale Baylands lead around salt ponds, water treatment ponds, and up over hills that were once landfills. Unfortunately, the levee trails around the salt ponds immediately to the east by the closed Alviso landfill and west by Moffett Field are not publicly-accessible at this time. The next Bay Trail segments to the east are easily reached by traveling through the wide and uncrowded streets of the historic bayfront community of Alviso. However, access to the Bay Trail segment to the west, starting at Stevens Creek, currently requires detouring along busy inland streets around Lockheed and Moffett Field until the proposed Bay Trail connection is completed.
Click the thumbnail below for a map of the Sunnyvale Baylands:
This is the entrance to Sunnyvale's Donald M. Somers Water Pollution Control Plant Facility at Borregas and Caribbean Drive. Carl Road is just ahead. Turn left on Carl to reach the Bay Trail entrance. (The landfill hill to the right of the entrance has a public trail over the top of it, but I wouldn't recommend it, as it goes above the sewage plant's sludge drying beds.)
Other access points to the Bay Trail are at Twin Creeks Sports Complex and Sunnyvale Baylands Park near the center. (Here are a map and directions to Twin Creeks and directions to Baylands Park.) The east end of the trail can be reached at Great America Parkway near the San Jose community of Alviso.
The VTA Light Rail system can also be taken to reach the Sunnyvale Baylands from as far north as downtown Mountain View or as far south as South San Jose and the Almaden Valley. (See here for the route map.) The Light Rail can be used to reach the Sunnyvale water treatment plant by disembarking at the Borregas Station and traveling down Borregas Avenue. Sunnyvale Baylands Park can be reached by disembarking at the Crossman Station, then taking Crossman north to Caribbean Drive, then turning right on Caribbean to the park entranceat Moffett Park Drive. The Light Rail also can be used to reach the Great America Station, which is near the San Tomas Aquino Creek Trail, which in turn can be taken to reach the Bay Trail. The Light Rail can be used to reach the Stevens Creek Trail and the Bay Trail in Mountain View by disembarking at the Evelyn Station or the downtown Mountain View station at the end of the line.
This is the Borregas Light Rail Station
Click here for road
and bicycle path maps.
A gravel road leads up to the top of the landfill hills. The hills have upland vegetation and animals. You can sometimes see jackrabbits hopping along the slopes. Raptors, such as hawks and turkey vultures, soar overhead. You might see burrowing owls perched on poles near their underground burrows.
This is a view looking back down towards the base of the landfill and the start of the Bay Trail. It shows the 3 trails next to the water treatment plant. The one on the left runs in a loop along the base of the hills. The one in the middle, to the left of the West Sunnyvale Channel, goes out to the Bay Trail segment that runs west to Lockheed Martin. It also leads to the trails around the water treatment ponds. The trail closest to the water treatment plant on the right is the Bay Trail segment that turns and runs east towards Alviso.
Looking back to the east of the West Sunnyvale Channel, you can see more landfill hills.
Looking east back down the gravel road, you can see the water treatment plant, the recycling center, and the Bay Trail to Baylands Park To the left is a huge salt pond on the east side of the Sunnyvale Baylands.
From higher up in the hills, looking slightly towards the northeast, you can look over the east salt pond. At the far end of it, a levee separates it from the Guadalupe Slough. Beyond it is a large salt pond next to Alviso that is currently off-limits. The closed Alviso landfill can be seen on the right behind the Guadalupe Slough.
Looking a little more towards the north below the landfill hills, you can see the levee on the west bank of the east salt pond. Running next to it is a swath of reeds that marks the path of the Moffett Channel. This is fed by the waters of the West Sunnyvale Channel and the output of the water treatment plant. The triangular pond below contains salt pond brine and is actually a bend in a long channel that connects the east salt pond with the privately-owned salt pond west of the Sunnyvale Baylands.
Looking towards the north, you can see the end of the east salt pond and the widening Moffett Channel, which flows into the Guadalupe Slough. West of the Moffett Channel is the radar antenna for Moffett Field. The triangular pond seen above ends at a levee. Beyond it is the east edge of the west water treatment pond.
Looking a little more to the left, you can see another channel past the foreground salt pond channel. On this channel, which contains partially-treated wastewater, you can see a pump station and pier. Beyond it, you may see a series of movable aerators near the end of the channel. If these are operating, they produce a dome of spray around them. This is to help oxidize the treatment plant effluent. Downwind of these aerators is not a good place to be if you have a sensitive nose, though they don't smell as bad as you might think. Beyond them is a dam and pump station on the large treatment pond to the left. All the levees seen above except for the one in the immediate foreground are open for hiking and biking.
Looking to the left more, you can see the series of parallel channels below and the huge water treatment pond beyond.
Looking towards the northeast, you can see the largest of the water treatment ponds. At its far northeast corner, you can see some structures. One is a pumping station on the edge of the large pond. Beyond that, on the Guadalupe Slough, are the NASA boat docks. To the west of the large water treatment pond is an even bigger series of salt ponds that belong to Cargill Salt and are currently off-limits.
Looking farther west, you can see the amazingly complex network of parallel channels and levees by Lockheed Martin and Moffett Field. Some of the levees are accessible. Some are not. The first levee on the left is Lockheed Martin property and off-limits. It runs on the edge of a freshwater marsh. The second one from the left is the Bay Trail route to the edge of Lockheed Martin property. It runs between two freshwater drainage channels. The next levee over belongs to Cargill Salt and is off-limits. The water to the left of it is salt pond brine. The next two levees to the right are part of the levee trails around the west water treatment pond and are public trails. The water to the left of each of them is wastewater being oxidized in the ponds.
Looking more to the west, you can see a view of the marshlands at the edge of Lockheed Martin's property.
The huge buildings of Lockheed Martin and Moffett Field can be seen to
the west of the hills. More development is going on in this area, so this
scene is likely to change.
Near the end of the parking lot at the west end of the Sunnyvale Water Pollution Control Plant, a marker indicates that this is an access point to the Bay Trail. You can park here. There is a portable restroom and a drinking fountain, along with a map of the trails in the area.
From the end of the parking lot, you have a choice of several trail routes. For now, head west towards the landfill hills. The trail mileage begins here. (Note: these mileage readings are from a bicycle odometer. Actual mileage may vary.)
West of the parking lot is the West Sunnyvale Channel. This tidal slough is a dirt-walled drainage channel that runs through the industrial park to the south. A fence blocks vehicle access to the levee banks to the south. Cross over the channel. Do not pass through the gate beyond the channel, but turn to the right along the trail that follows along the west bank of the West Sunnyvale Channel.
The trail passes by several channels and levees. The first channel is a freshwater drainage channel that drains the wetlands next to Lockheed. A pump station at the end of it pumps the water into the West Sunnyvale Channel. The first levee is the Bay Trail route to Lockheed Martin. The channel past it is the Moffett Drain, which drains the runoff from Moffett Field. A pipe connects the 2 drainage channels together. The next levee past it belongs to Cargill Salt and is closed off. The wide channel to the right of it is a salt pond channel. Beyond that are the levees around the west water treatment ponds and will be covered in Part 2. Take the first levee to the left, at 0.1 miles, which has a Bay Trail sign marker. The levee that the Bay Trail is on runs straight and parallel to the landfill hills. The drainage channel to the left is lined with small stands of cattails.
Near the end of the landfill hills at 0.4 miles, a short trail leads up into them. The water in the drainage channel flows through a pipe under this short trail.
After passing the end of the landfill hills, you pass by a power tower and come to a gate at 0.45 miles. This gate once blocked access to the levee beyond, but it is now open.
To the left of the trail, beyond the nearby marsh, new high-tech industrial parks are being built. The large buildings in the pictures belong to Yahoo! Corporation. The marsh extends south along the base of the landfill hills.
The marsh to the left is a freshwater marsh, filled with tall cattails. It begins to widen.
Ahead, the levee trail and parallel channel begin to curve to the right.
The marsh on the right widens into a large triangular pond. At around 0.6 miles, the trail turns right to skirt around it, then turns left at 0.8 miles and runs straight, paralleling the shoreline.
At 0.9 miles, a levee divides this large pond from a smaller pond. The levee is an entrance to Lockheed Martin and is off-limits.
In the salt pond channel to the right of the trail, the channel widens out to a large pond. A line of power towers runs through the salt ponds. A broken catwalk runs between the towers.
Beyond the second pond on the left of the trail is another pond that is behind a fence. The trail runs next to this fence.
Finally, the trail ends at a gate in the fence at 1.2 miles. This gate leads into Lockheed Martin property, and the road beyond is off-limits.
Just ahead, a fence prevents further travel west along the shoreline. Signs indicate the beginning of NASA property. The green lawns of the Moffett Field Golf Course can be seen ahead on the left.
The Moffett Drain channel on the right flows under a bridge. A road goes over the bridge and leads out to the NASA boat docks, which will be seen in the tour around the west ponds in Part 2. The Cargill levee on the right of the channel intersects this road and leads to the private salt pond beyond, which is blocked by another locked gate.
This is currently the end of the line for the Bay Trail so far. There are plans in the works to extend the Bay Trail along the edge of Moffett Field to reach the Stevens Creek Trail and the Bay Trail at Shoreline at Mountain View. (See here for a map.) However, for now, unless you work for Lockheed Martin or NASA, the only thing you can do is turn around and come back along the trail.
These are views looking back along the trail. The landfill hills can be seen to the right.
This is a view looking back along the West Sunnyvale Channel towards the
trail entrance and the landfill hills on the right. Turn left and cross
back over the West Sunnyvale Channel.
Back by the parking lot at the water treatment facility, there's a gate immediately to the left just before the end of the parking lot. There's a drinking fountain here and a trail map mounted on the gate. Go through the gate. The trail mileage begins here.
On the side of the trail next to the water treatment plant is an interpretive sign describing the area. There are several interpretive signs along the trail from here to the East Sunnyvale Channel.
Beyond the fence are the water treatment plant facilities.
The trail follows on top of the levee east of the West Sunnyvale Channel. As the channel turns to the right, so does the trail, at 0.1 miles, following along the outside edge of the water treatment plant. Here, tall bushes and trees line both side of the trail. A depression on the right is filled with vegetation. Ahead, it gets deeper and turns into a drainage channel.
On the left, at 0.2 miles, the Moffett Channel branches off from the West Sunnyvale Channel and heads north towards it confluence with the Guadalupe Slough. The NASA radar tower can be seen, with the east salt pond visible to the right of it. The drainage channel on the right gets wider and deeper.
An interpretive sign on the right side of the trail describes the water treatment plant's history and facilities. The plant can now treat almost 30 million gallons a day.
The trail emerges more into the open, with marsh plants on both sides. The SMaRT recycling center can be seen ahead.
The channel on the left soon dead ends at 0.35 miles. (This is a view looking back.)
To the north, you begin to see the huge east salt pond. The main trail soon meets the somewhat overgrown levee trail leading around the east salt pond. Bay Trail signs flank this trail and point along the main trail as if to discourage people from taking the salt pond trail The trail around the salt pond is unmarked, but is not blocked off and is accessible, if not always in great shape. This will be covered in Part 2.
To the right, there is a fenced-off stormwater pumping station and a closed service road that leads to the recycling station. Three parallel drainage channels begin on the right below the recycling center.
At 0.5 miles, a sign below the landfill describes the SMaRT (Sunnyvale Materials Recovery and Transfer) recycling station. Garbage trucks come here where the trash is separated into recylables. The landfill beyond it is used for concrete and asphalt recycling. The unrecyclable garbage is trucked to the Kirby Canyon Landfill in San Jose for disposal.
The Bay Trail runs along the edge of the east salt pond.
In the salt pond are the remains of a levee that forms a series of small islands that serve as safe resting areas for birds.
The trail begins to reach the end of the landfill hills. At 0.9 miles,
the landfill hill ends. The two nearest drainage channels dead end. The
channel closest to the hill turns right and follows the base of the hill.
Beyond the landfill hills is the East Sunnyvale Channel. Trails run along both sides of the East Sunnyvale Channel, but may not be open at the other end. A bridge crosses over the channel, while a trail continues east along the salt pond. This will be described in Part 2. For now, cross over the bridge to follow the Bay Trail.
This is a view looking back across the East Sunnyvale Channel at the bridge.
After crossing over the bridge, turn left. The Bay Trail here is a wide gravel road. The part nearest the channel is elevated. The channel is filled with marsh plants.
Immediately after crossing the crige, the trail runs behind the 60-acre Twin Creeks Sports Complex. This softball complex was built in 1985. It includes 10 softball fields and other sports facilities.
Beyond Twin Creeks, starting at 1.3 miles, is a large pickleweed-covered field that is part of the marsh at Sunnyvale Baylands Park, which will be covered in Part 3.
The channel narrows and begins to curve to the left.
Near a large mound of dirt, it joins the Guadalupe Slough at 1.4 miles.
The trail soon begins to follow the wide Guadalupe Slough. This used to be the outlet of the Guadalupe River, before it was artificially re-routed to the Alviso Slough many years ago. Now it is the outlet of San Tomas Aquino and Calabazas creeks.
The banks of the Guadalupe Slough are covered with bulrushes. Beyond them, the buildings of Alviso can be seen in the distance.
A large rectangular pond appears on the right at 1.5 miles. This is the Open Water Bird Preserve. It is fed by the waters of the Guadalupe Slough. A narrow trail runs along the west and south sides of the pond.
The pond is an excellent place for bird-watching. Across it to the south are Hwy 237 and high-tech industrial campuses.
The Bay Trail runs along the north side of the pond next to the Guadalupe Slough.
At the corner of the pond at 1.9 miles, the trail turns right to run along the east edge of the pond next to a wall. On the other side of the wall is Calabazas Creek, which joins the Guadalupe Slough at this corner. At the southeast corner of the pond, the narrow path around the pond rejoins the Bay Trail at 2.0 miles. Farther along Calabazas Creek, a floodwater pump station appears on the right. Big pipes are on the Calabazas Creek side to the left. The pump station is off-limits. A paved road leads to the pump station, so the last segment of this trail is paved. At 2.1 miles, a narrow levee trail leads through seasonal wetlands.
The paved trail along Calabazas Creek reaches a junction at a larger paved trail at the creek bridge at 2.2 miles. (This is a view looking north back along the creek.) There is an open gate here. On the gate is a trail map.
The wide paved trail is a former road, now closed to automobile traffic. To the west, it leads into Sunnyvale Baylands Park, which will be covered in Part 3. It is 0.7 miles from here to the east end of the parking lot in the park.
To the east is Calabazas Creek. Informal trails lead along Calabazas Creek underneath the Hwy 237 bridge. The Calabazas Creek Trail will be covered in Part 3. Cross over the Calabazas Creek Bridge. The city of Sunnyvale ends at Calabazas Creek Beyond it and north of Hwy 237 is the city of San Jose. South of 237 is the city of Santa Clara.
Beyond the bridge, a gravel trail leads to the left between Calabazas Creek and a tidal marsh, the Harvey Marsh. This trail, which is covered in Part 3, runs between Harvey Marsh on the right and San Tomas Aquino Creek on the left. The Bay Trail continues on the paved trail between Harvey Marsh and Hwy 237.
The trail nears a creek again at 2.6 miles. This time it is the larger San Tomas Aquino Creek. On the west side of the creek, is the end of the gravel path that leads around Harvey Marsh. A ramp leads down to the creek and heads south under the bike trail bridge and the Hwy 237 bridge along the creek banks. This is the currently-undeveloped but accessible beginning of the San Tomas Aquino Creek Trail, which is covered in Part 3.
Cross over the San Tomas Aquino Creek Bridge. On the east side of the creek, another path heads left to the edge of a landfill. "No trespassing" signs warn against exploring this area. Toxic warning signs hint at one reason why. A ramp leads down to the creek and follows the creekbank south.
Past the creek bridge, the path parallels a long, narrow seasonal pond, remnants of a salt pond, next to the landfill hill. The bike path ends at Great America Parkway at 2.8 miles. This is the end of the Bay Trail.
The road can be taken to Alviso and the long trails around its salt ponds. To get there, turn left on Great America Parkway and take it to Gold Street, then turn left. You cross over the Alviso Slough at 3.5 miles, but the wide levee trails are currently closed at this point. Turn left at Moffat Street, right on El Dorado Street, left on Catherine Street, and left on Hope Street. Behind the South Bay Yacht Club are stairs up to the Alviso Slough levee. You can also continue a little farther on and take a dirt ramp up to the levee. Once on top, turn right and take the levee trail to the Alviso Marina, which you reach at 4.4 miles. Continue to the other end of the parking lot to reach the Alviso Slough trail entrance at 4.5 miles.
Go to Part 2 - The Baylands Ponds
Go to Part 3 - Sunnyvale Baylands Park and Nearby Trails
Go to the Mountain View - Stevens Creek Trail Tour
Go to the Alviso Tour
Return to the Bay Trail Guided Photo Tours page