Alviso: Town and Slough

Mouth of the Alviso Slough
Town of Alviso and Marina
Alviso Slough Trail Loop Description and Views


The tiny, quiet San Jose community of Alviso seems like it belongs in another place and time. With its wide, uncrowded streets, old wood and brick buildings, junkyards full of rusting machinery, and a population of a little over 2000 that is nearly 3/4 Hispanic, it seems more like a quiet Central Valley farming town, rather than a corner of the "Capital of Silicon Valley." Alviso used to be an independent city, with a long history. It was started in 1836 and incorporated as an independent city in 1852. It was a busy and prosperous port, shipping agricultural products from the Santa Clara Valley and mercury from the New Almaden mines. In 1864, the completion of the railroad from San Jose to San Francisco caused the decline of the commercial use of the port. Alviso became part of the city of San Jose in 1968, and because of it, San Jose can claim it has a waterfront on San Francisco Bay, albeit a tiny one. Alviso is located at the southernmost arm of San Francisco Bay, between the drainages of the Coyote Creek/River and the Guadalupe River. Alviso has a rich historical background. The 130-year old town is listed in the National Register of Historic Places. Though often overlooked, neglected, and overshadowed by its flashy high-tech neighbors, it is one of the most unique and colorful communities in the Silicon Valley. Though high-tech development is lapping at its doorstep, it is one of the last genuine reminders of what the Santa Clara Valley was like before it became siliconized.

The main attraction of the Alviso area for bike riders, walkers, and joggers are the miles of trails on the levees in the area. This area has some of the longest, but loneliest trails on the Bay Trail. They allow you to get away from crowds and get close to nature. This area has thousands of acres of marshes, salt ponds, mud flats, sloughs, freshwater creeks, and bay shallows. It is incredibly rich in wildlife, especially in bird species. There are some 250 species of resident and migratory birds here. It is a bird watchers paradise and a good place for wildlife studies. The San Francisco Bay Bird Observatory is headquartered in Alviso and conducts studies of birds on and around the Bay. The salt ponds and wetlands in the Alviso area are part of the Don Edwards San Francisco Bay National Wildlife Refuge, administered by the US Fish and Wildlife Service. The ponds are surrounded by levees, some of which are open to bikers and walkers, while others are closed to protect the wildlife. The accessible levees are dirt-surfaced, but they are flat, smooth, and easy to ride on--when they are dry, that is. They are made from dredged, dried bay mud, which makes for a smoother ride than gravel roads. However, the mud does not dry very fast after a rain and can get muddy. The mud is very sticky and slippery, which makes walking and bike riding difficult and dangerous.  The trails are not suitable for travel during the rainy season.  Another challenge is the wind. Alviso is located at the southernmost point of San Francisco Bay. In the afternoons, the Bay winds come whipping unimpeded down the Bay, making upwind travel difficult, but making downwind travel easy. The best time to come here is in the morning, when the winds are usually lighter.

The trails here are primarily loop trails, rather than connector trails. They are destinations in themselves, rather than a means to get to other destinations. There are two main trail loops in the Alviso area: The 9-mile Alviso Slough Trail Loop and the 5.5-mile Mallard Slough Trail Loop. The Alviso Slough Trail Loop is the more popular one and is in better condition. It follows the Alviso Slough to its junction with the Coyote River and the Bay. The Mallard Slough Trail, which lies to the east of the Alviso Slough Trail,  leads to the San Francisco Bay National Wildlife Refuge Environmental Education Center. The Mallard Slough Trail and the Environmental Education Center are covered on a separate page.

Access Information

The Alviso Slough Loop Trail, the largest network of trails, is accessible from the Alviso Marina. The Marina is located at the end of Hope Street, which can be reached by taking Lafayette Street north from Santa Clara or 1st Street northwest from San Jose. Lafayette turns into Gold Street. 1st Street turns into Taylor Street, which intersects Gold Street. Turn right onto Gold Street. Continue on Gold Street, which turns left and becomes Elizabeth Street. Elizabeth T's onto Hope Street. Turn right and go over the bridge to the Marina.

From the Peninsula, take Hwy 101 to Hwy 237, get off at the Great America Parkway exit, turn left, then follow the road for a short distance until it hits Gold Street. Then turn left.

From the East Bay, take 880 to 237 to the 1st Street exit. Turn right and follow 1st Street to Gold Street as above.

Alviso can easily be reached from the west via the Bay Trail from Sunnyvale Baylands Park. The off-road trail ends at Great America Parkway. Great America Parkway continues on for a short distance, then T's on Gold Street.

East of Alviso and north along the East Bay, there are huge gaps in the Bay Trail. The nearest completed off-road segment is the isolated strip along the Coyote Creek Marshlands off Fremont Blvd. behind Bayside Business Park. Beyond that, it is a long distance to the vast complex of trails in the Newark/Coyote Hills area.

Click on the following pictures to see a larger version. Hold your cursor over the pictures to read the captions Note that the mileage readings below were taken from a bicycle odometer. Your mileage may vary.

Town of Alviso and Marina

Tilden-Laine House in Alviso The Victorian Tilden-Laine house, on Elizabeth Street was built in 1887 by Susan Tilden. Descendants of the Tilden family still live here. This is one of the best examples of Victorian architecture in town.

Bayside Canning Company building The old Bayside Canning Company building sits on Hope Street, just south of the Marina. It is covered by murals depicting scenes from the history of Alviso. It is no longer used as a cannery. The cannery was started in 1907 by Sai Yen Chew. It was passed onto his son, Thomas Foon Chew, who canned asparagus and became known as the "Asparagus King."  In the 1920's, the operation was the third largest cannery in California. The cannery closed in 1936, a victim of the Depression and the death of Thomas Chew. The San Francisco Bay Bird Observatory currently uses the property.

Houseboat by Alviso Marina This houseboat sits on dry land near the "pond" next to the Alviso Marina.

The Alviso Marina is a Santa Clara County Park. The marina facilities currently include a large parking lot, restroom, water, and picnic tables. There are plans (which are on display here) to develop the marina area, but they are currently on hold due to concerns over endangered species.

Boat stuck in bulrushes in former Alviso Marina The Alviso Marina used to be an active small craft harbor. Dredging was required to keep it navigable. In the 1970's, dredging was stopped for environmental reasons, and reeds and silt filled the marina, stranding a few remaining boats. The marina docks and gates are still in place, but are closed.

Old dock in former Alviso Marina At the end of the marina is an old, decaying dock and launching ramp that now lead into the reeds.

For further exploration, go to the north end of the marina and take the trail to the left along the Alviso Slough. It passes along a levee above the slough. Tall rushes line the slough. The levee runs above the town. The old Bayside Cannery buildings lie below the trail to the left.

South Bay Yacht Club The blue wooden building housing the historic South Bay Yacht Club is further down on the left. The yacht club traces its origins to the late 1880's. The club house was built in 1903, but was moved to its current location in 1985 to protect it from flooding.

Boats on the Alviso Slough Boats are docked in the slough to the right. The slough is navigable at high tide and provides access to San Francisco Bay for small boats.

Train bridge over Alviso Slough The trail dead ends at the railroad bridge. The bridge marks the boundary where the Guadalupe River becomes the Alviso Slough. The Guadalupe River originally drained into the Guadalupe Slough. The Guadalupe Slough is a little to the west in the Sunnyvale Baylands, but the course of the river was changed near the turn of the century to its present outlet, which was then called Steamboat Slough. This was to provide a more efficient shipping route.

The land on the other side of the railroad bridge is part of a landfill that has been closed. It contains hazardous materials and is off-limits to the public. There are levee roads on either side of the Guadalupe River, but they are currently fenced off.  Plans are in the works, however, to provide recreational trails along the Guadalupe River, through downtown San Jose to the Guadalupe River Park and Gardens, and all the way up through the Almaden Valley to the Alamitos Creek Trail. It also will connect to the Los Gatos Creek Trail.

Alviso Slough Trail Loop Description and Views

The trails follow along levees that ring the salt ponds. There are seven salt ponds west of the railroad tracks. The ponds generally increase in salinity from west to east. The ponds belong to the San Francisco Bay National Wildlife Refuge, but the Cargill Salt Company has salt evaporation rights to them and maintains the levees. The trail around the salt ponds is officially part of the Bay Trail. You can take the trail clockwise starting at the Marina, following along the levee above the Alviso Slough, with the salt ponds on your right. This part of the trail follows the winding path of the slough, which gets wider as it approaches the bay. This direction is into the wind, so it's best taken early in the day, when the winds are calmer. Several small levees branch off from the trail, dividing up the salt ponds. Most of these are closed, however. Only one trail on a levee between the salt ponds is open. The loop around the salt ponds is 9 miles long, so it is a little long for walking the whole distance, but ideal for biking. There may be some walkers on the trail near the Marina, but the farther out you go, the more likely you will be alone. Note that there are no restroom facilities, shade, benches, or drinking water on the trails.

Bay Trail by Alviso Marina heading west Starting at the Alviso Marina's parking lot, head to the east end. Here is start of two trails. The one on the left stays at the same level as the parking lot and runs around the marina. The trail on the right drops down to the slough level. This will be used on the return route, so take the trail on the left.

Salt pond by Alviso Marina, looking north Follow the trail around the end of the marina until it meets the junction with the lower trail at a huge salt pond. Turn left and follow the trail along the back side of the bullrush-filled marina.

At 0.2 miles, the trail turns as the marina basin narrows. At 0.3 miles, it passes the end of the marina and begins to follow the Alviso Slough on the left. The trail makes S-curves as it follows the slough. In the distance across the slough to the west, the landfill hills of the Sunnyvale Baylands can be seen, with the hangars of Moffett Field, and salt ponds below them. Directly beyond the opposite bank of the Alviso Slough are salt ponds and levees that are currently off-limits to the public. Straight ahead are the Coyote Hills.

The slough moves farther away. Cordgrass fills the gap between the trail and the bulrushes along the slough. At high tides, bay waters fill the slough from bank to bank. At low tides, wide mud flats are exposed.

Small beach along salt pond by Alviso Marina Meanwhile, in the salt ponds to the right, the water levels are constant. The salt ponds here look like huge lakes. Little vegetation grows along the edges of the saltier eastern salt ponds. However, the ponds are filled with life. Gulls and ducks float on the surface, while long-legged stilts, egrets, and great blue herons stalk fish along the edges.

At 1.0 mile, the trail passes by a yacht stranded in the muddy banks of the slough. This point is far from the mainland. The only sounds are the wind, the birds, and the jets taking off from San Jose Airport.

Plants by side of trail along Alviso Slough The trail begins to make a long half-circle around a marsh. The trail comes closer to the slough.

Sailboat stranded in marsh by Alviso Slough At 1.2 miles, the slough makes a sharp left curve away from the trail, leaving a broad cordgrass-covered marsh between it and the trail. The mast of a stranded sailboat pokes up above the tall grass.

Heron by closed salt pond levee At 1.4 miles, the trail passes by a levee on the right. Like most of the levees that cross through the salt ponds, this one is closed to protect the wildlife. The levees divide the salt ponds. Each pond has different salinity levels. Water is piped from one pond to another. Birds often gather near these pipes to feed on the fish that are carried through them.

Mudflats along Alviso Slough The trail turns left, then curves to the right. Mud flats appear on the left at low tide. The slough is now far away across a wide marsh.

Alviso Slough with Moffett Field hangars in background At 2.1 miles, the trail heads straight towards another inner levee across the salt ponds, but this one is also closed. Turn left to follow the outer levee. Along the shore to the left, the enormous black and silver Hangar 1 of Moffett Field and the gigantic wind tunnels at NASA Ames Research Center are visible. The slough gradually begins to come back towards the levee.

Pickleweed along banks of Alviso Slough At 2.4 miles, the slough is visible again. Pickleweed, covered with bright orange threads of the parasitic dodder plant, separate the trail from the slough.

Alviso Slough next to trail By 2.5 miles, the wide slough runs just below the levee trail. On the opposite shore is a wide marsh.

Small pond in marsh by Alviso Slough At 2.7 miles, the trail passes the wreck of a small boat, stuck in the pickleweeds. The marsh widens, and small pools appear in it near the trail. The trail begins to make a wide curve around a bay in the salt pond.

Wide section of Alviso Slough At 3.7 miles, the trail passes by another closed levee. To the left, the slough is very wide now, with extensive mud flats along its banks at low tide.

Beyond the opposite bank of the slough is a large salt pond called the Knapp Tract, which is bordered by the Guadalupe Slough, San Francisco Bay, and the Alviso Slough. This is part of the refuge, but is closed to the public, though the San Francisco Bay Bird Observatory and their volunteers are allowed to take bird surveys there.

The salt pond on the right has pickleweed growing along the edges and may have mats of algae floating on the surface of the pond. This indicates this pond is less salty than the ones farther east. It is actually an inlet pond, so the waters near the inlet are similar in salinity to the Bay waters.

Salt pond intake valve structure on Alviso Slough At 4.0 miles, a large water valve structure appears on the slough side, with pipes on the salt pond side. This lets water from the slough enter the salt pond. The slough touches the side of the trail here, then gradually pulls away, with marshes filling the gap again.

Marsh at the confluence of the Alviso Slough and Coyote Creek At 4.1 miles, the trail turns to the right as it reaches the farthest point of the levee along the Alviso Slough. Straight ahead is a huge marsh and mud flat, at the confluence of the Alviso Slough and the Coyote River. A line of giant power towers crosses the Bay in this area. In the distance is the Dumbarton Bridge.

The trail now begins to leave the Alviso Slough and follows the Coyote River upstream. The river is actually a large tidal slough here. Very little freshwater flows down Coyote Creek in the dry months of the year. However, freshwater discharges from the nearby San Jose water treatment plant make the water more brackish than it would be otherwise. Narrow pickleweed marshes and broad mud flats border the creek at low tide. The trail begins to turn downwind from here, so the going is easier.

Boats stuck in mud on Coyote Creek At 4.4 miles, an abandoned sailboat and fishing boat are stuck in the mud along the river. The wind blowing the sailboat's rigging against the mast causes a ghostly ringing sound. The trail begins to turn to the right. The marsh on the left gets broader, with small channels running through it.

Closed salt pond levee by Coyote Creek At 5.3 miles, a narrow and bumpy levee heads off to the right across the salt ponds. This is not open to the public. The main outer trail continues off to the left.

Marsh by Coyote Creek At 5.5 miles, the trail makes a 90 degree bend to the right around a corner of the salt pond. The Coyote River is barely visible to the left across the wide marsh.

At 5.7 miles, the trail leads straight ahead into a wide levee that crosses through the salt ponds. This is the only trail between the ponds that is accessible to the public. This route will be described separately below.

Tidal pond by Coyote Creek At 6.0 miles, a round tide-fed pond lies adjacent to the left side of the trail. The Coyote River is visible again beyond the marsh. The marsh becomes wider, and is triangle-shaped. It is known as Triangle Marsh. Because of the freshwater discharges along nearby Mallard Slough, the vegetation and wildlife here are more characteristic of brackish environments, rather than salt marshes.

Triangle Marsh and Coyote Creek train bridge to Station Island At 6.4 miles, power lines carried by wooden power poles cross the trail and head towards a pumping station in the middle of the salt ponds. A train bridge crossing the Coyote River can be seen in the distance. The tracks lead to Station Island on the left.

View of ghost town of Drawbridge Station Island is the location of the ghost town of Drawbridge. The rooftops of about a dozen and a half decaying building can be seen poking up above the marsh plants. Access to Drawbridge is restricted to guided tours only, which originate at the San Francisco Bay National Wildlife Refuge Headquarters in Newark. The best view of Drawbridge is from the north Mallard Slough Trail.

Railroad tracks leading north to Station Island At 7.1 miles, a path leads east across the railroad tracks that run through the center of Alviso to Station Island and beyond. This is a busy railroad route. Frequent freight trains and Amtrak uses it. On the other side is the Mallard Slough Trail. Continuing down the main trail, a narrow channel runs between the trail and the railroad tracks on the left. The trail turns to the right and heads south, paralleling the railroad tracks.

At 7.5 miles, the accessible levee trail cutting through the salt ponds rejoins the perimeter trail.

Amtrak train by Alviso Slough trail At 8.0 miles, the salt pond east of the railroad tracks ends, and the New Chicago Marsh begins. The trail curves to the right as the channel to the left of the trail widens into a broad mud flat.

Rocky salt pond levee At 8.1 miles, the trail passes by a closed levee. From here on, the trail continues ruler-straight along the edge of the salt pond to the right. Prevailing winds tend to blow algae and other organic matter up against the shore of the ponds here. When this organic matter decays, it can create a strong odor. Bicyclists can speed past this area, but walkers with sensitive noses may want to avoid it.

At 8.8 miles, the trail reaches the end of the salt pond and the junction with the higher-up trail that leads around the marina. Continue on the lower trail to the trail entrance at 8.9 miles.

Mid-Pond Trail
The following is a description of the mid-salt pond trail seen at 5.7 miles above. This is the only accessible levee trail in the Alviso Slough Loop that runs between salt ponds. Thus, salt ponds surround the trail on both sides. Because the levee divides the ponds, they vary in salinity and character from one side of the trail to the other. These are active salt ponds, so there may be water pumping activities going on. The inner levee trail makes a long, curving path that roughly parallels the straighter outer trail.

Birds on salt pond levee The levee is wide and flat. Because it is lightly used, large flocks of waterfowl may settle on it.

Pump station on salt pond  levee Here is a pump station on the salt pond. Power for the pump station comes from power lines that run along the north side of the slough trail.

Birds on closed levee The trail passes by an uneven-surfaced levee that is closed to public access. Birds use it for nesting.

After 0.7 miles, the trail reaches the main levee trail heading south to the Alviso Marina.

For more on the Alviso area, see the "Alviso: Mallard Slough & Environmental Education Center" page.

Developed: 12/29/99 by Ronald Horii

Information and opinions here are the responsibility of the author