Description & Views
 Bayland Hills
 Treatment Ponds
 Pond A4
 Open Water Preserve
 Baylands Park
 Harvey Marsh
 Calabazas Crk Trail
 JWC Greenbelt


Sunnyvale Baylands

Update 2011

A great egret fishes in a water treatment channel, with Yahoo! headquarters in the background.


Many years ago (in 2001), I made a series of webpages on the Sunnyvale Baylands for the Bay Trail Project (see the links on the left). While those pages cover the Sunnyvale Baylands in great detail, and most of the trail descriptions and mileage measurements are still valid, there have been some changes in the area. Also, the pictures on those web pages were scanned from paper prints and were small and low resolution, as Internet speeds were very slow in those days. These pages are an update to those original Bay Trail pages. They are not intended to replace them, but to supplement them with newer and higher-resolution pictures taken with digital cameras. Most of the pictures were taken on November 13-14, 2011, but a few of the John W. Christian Greenbelt were taken in 2007.

These are some changes that have happened since those original Bay Trail pages were published:
  • In 2010, the Bay Trail now goes past Moffett Field to Stevens Creek.
  • The San Tomas Aquino Creek Trail is complete and paved all the way from the Bay Trail to Cabrillo Ave. in Santa Clara.
  • The closed landfill at the end of Great America Parkway has been developed. There are 2 large office buildings on top of it.
  • The Calabazas Creek Trail is partially complete. It is paved and continuous from Mission College Blvd. to Tasman Drive. It is further paved from Tasman to Moffett Park Drive. It is a dirt trail from there to the Bay Trail.
  • The Guadalupe River Trail is complete and continuous all the way from downtown San Jose to Alviso. North of Hwy 101, it runs on both sides of the Guadalupe River. There is now a gazebo, water, and restrooms at the end of the trail on Gold Street.
  • There are plans for modifying the East and West Sunnyvale Channels for flood control. They will be re-routed to drain into pond A4. There may be trails along the levees. Right now, there are "no trespassing" signs along those levees.
  • The levee road around pond A4 is not an official trail. There are no gates or fences preventing access, but there is a small "no trespassing" sign at the west end.
  • The salt ponds in the South Bay were sold by Cargill Salt to the US Fish & Wildlife Service. The South Bay Salt Pond Restoration Project is involved in converting the salt ponds back to tidal wetlands, where possible.

SF Bay Rec & Travel Home

Sunnyvale Baylands Bay Trail Map

Sunnyvale Baylands Park

County Parks: Sunnyvale Baylands Park

Sunnyvale Baylands Park Map

Access Information

There are several access point for the Sunnyvale Baylands. These pictures were taken starting from the Sunnyvale Water Pollution Control Plant, which is located on Borregas Avenue and Carl Road, just off Caribbean Drive, between Lawrence Expressway and Mathilda Avenue. (Tours of the plant are available.)  It can be reached from Hwy 101 northbound from points south by taking the Lawrence Expressway exit and following Lawrence Expressway east. After it crosses over Hwy 237, it becomes Caribbean Drive. Turn right on Borregas Avenue into the recycling facility access road, then turn left on Carl Road. Follow it to the end. From Hwy 101 from points north, take the Hwy 237 exit towards Milpitas, then exit at Mathilda Avenue. Turn left onto Mathilda and take it north. It turns right and becomes Caribbean Drive. Turn left at Borregas Avenue and follow the directions above. From the East Bay, take Hwy 880 to Hwy 237 westbound. Exit at the Lawrence Expressway/Caribbean Drive exit, turn right, and follow the directions above.

The most popular entrance to the Sunnyvale Baylands is at the developed Sunnyvale Baylands Park, located on Caribbean Drive next to Hwy 237. There is ample parking in the park, but fees are charged from March through October.  Parking is free next door at the Twin Creeks

The Bay Trail can be used to access the Sunnyvale Baylands from the east. The trail starts in Alviso and is a short distance from the end of the Guadalupe River Trail on Gold Avenue. The trail is continuous all the way to the Guadalupe River Park and Gardens in downtown San Jose. A short distance from Alviso is the start of Santa Clara's San Tomas Aquino Creek Trail, which runs past the Santa Clara Convention Center, Great America, under Hwy 101, under Central Expressway, and ends at Cabrillo Avenue. A little farther along the Bay Trail is the start of the Calabazas Creek Trail, which is shown below.

See the Stevens Creek Trail page for access information from the Mountain View end.  The new section of the Bay Trail connects Stevens Creek to the west end of the Sunnyvale Baylands. The Bay Trail is continuous from Stevens Creek to Shoreline at Mountain View, the Palo Alto Baylands, and Ravenswood Open Space Preserve.

Bay Trail Links:

Bay Trail Home

Bay Trail Map: South Bay

Guided Photo Tours

My Bay Trail Pages

Old Bay Trail Pages on the Sunnyvale Baylands (2001):
Part 1, Part 2, Part 3

Moffett Bay Trail (2010)

San Tomas Aquino Creek Trail

Guadalupe River Trail to Alviso

Alviso Bay Trail: Part 1Part 2

Alviso Marina Sunset 11/27/10

Alviso Mallard Slough Trail Mobile Phone Tour 10/26/14

Palo Alto Baylands (2000)  

Palo Alto Baylands Preserve (2010)

High Tide at Palo Baylands & Byxbee Park, 11/26/11

High Tide at Palo Baylands & Byxbee Park, 8/30/14

Stevens Creek Trail (2002)

Stevens Creek Trail (2012)

Stevens Creek Trail to Cooley Landing  8/15/12
Shoreline Park Mountain View (2002).

Shoreline Park Mountain View (2010)
Ravenswood (2010)

Dumbarton Bridge (1999, 2004)

Menlo Park (2000)

Redwood City (2007)

Redwood Shores 7/5/13

Don Edwards SFBNWR (2002)

King and Low Tide, Hayward Shoreline, 1/25, 1/29/14

Description and Views

Bayland Hills

Below are pictures from the Sunnyvale Baylands, beginning at the landfill hills at the end of Carl Road at the Sunnyvale Water Pollution Control Plant, and ending near Sunnyvale Baylands Park.

This is a panorama taken from the former landfill hills. The picture is stitched together from 10 separate shots. Click on the thumbnail above for a larger version, 10,994 X 1080 pixels. Ahead are the water treatment channels and ponds. Former salt pond A4 is to the right. The ponds by Yahoo! and Lockheed-Martin are to the left.The Bay Trail runs past them and continues on past Moffett Field to Stevens Creek. The hydrology of the area is very complicated, with parallel channels and levee trails, some accessible, some not. See the old Sunnyvale Baylands page for an explanation.

On the lower part of the hills is a viewing site, with bench, binoculars, and Bay Trail mapboard. A ramp leads to a trail that runs around the base of the hills.

Visitors check out the Bay Trail map and watch the great egret feeding nearby.

A Jogger runs on the Bay Trail leading to Moffett Field. This shows the many levees. The next one up is open to authorized personnel only. Above that are levee trails that run around and through the water treatment ponds. In the background are the open waters of the Bay. On the horizon are the white salt mounds of the Newark salt processing plants.

Water Treatment Ponds

The 440-acres of water treament ponds are former salt ponds. They were purchased in 1962 for use as oxidation ponds for the adjacent Sunnyvale Water Pollution Control Plant. Wastewater circulates through the ponds for about 30-45 days, where bacteria and algae digest the organic nutrients in the wastewater. Algae produces oxygen by photosynthesis, which benefits other pond organisms. Pumps and sprayers provide further aeration. There is a network of levees and channels, providing miles of trails, all of which are accessible. The ponds attract huge numbers and varieties of birds.

Birds on a water treatment channel, with aerators in the background.

A black-crowned night heron rests on cattails at the edge of a water treatment channel.

Cormorants, a pelican, and a seagull rest on old wooden structures.

Flocks of birds on the water treatment channel and levee.

More birds on the water treatment channel and levee.

Pelicans and cormorants rest on the remains of catwalk pilings, while a great egret fishes in the background.

A great egret fishes next to a levee. Beyond it is a former salt pond. In the background are the hills of Coyote Hills Regional Park on the left and the headquarters of the Don Edwards San Francisco Bay National Wildlfe Refuge, both across the Bay in Fremont. The salt pond used to be owned by Cargill Salt, but is now part of the National Wildlife Refuge. Duck hunting is permitted in the refuge. Duck blinds can be seen in the pond.

Birds of all kinds are on the west water treatment pond. The active landfill hills are in the backbround on the right.

More birds on the west water treatment pond. The Moffett Field radar tower is in the background. The office buildings on the left are built on former landfill hills in Alviso.

More birds are near the northwest corner of the west water treatment pond. A trio of snowy egrets stand in the cattails. In the background on the left are the hills north of Mission Peak above Fremont.

On the west treatment pond, small groups of ducks are swimming and feeding in tight circles.

At the northwest corner of the west pond, the Guadalupe Slough comes into view. On the slough, behind fences, are the old boat docks that were once used for unloading jet fuel from barges for planes at Moffett Field. The slough widens out as it heads towards the Bay.

These birds are on the Guadalupe Slough, with Mission Peak in the background.  The Guadalupe Slough runs along the north side of the water treatment ponds. It is open to the Bay, so is subject to tidal flow. The bank on the far side of slough divides it from the former salt ponds at Alviso.

Pond A4

Pond A4 is a 320-acre former salt pond, owned by the Santa Clara Valley Water District. It is located east of the water treatment ponds and the Moffett Channel. The Guadalupe Slough flows around its northern and eastern sides. The Bay Trail runs along its southwestern side. Small islands and peninsulas were built in the pond to prevent levee bank erosion. They are now used by birds for resting.

These pelicans are on an island in the former salt pond designated A4.

There are interpretive signs all along the Bay Trail here. This sign talks about the salt ponds.

Feeding on an eroded island in pond A4, a great egret is on the left, while a flock of black-necked stilts is on the right.

Ducks, Canada geese, and snowy egrets rest on another island in pond A4.

This is the Bay Trail running along the south bank of Pond A4. In the distance is a bridge over the East Sunnyvale Channel.

This is the Guadalupe Slough southeast of pond A4.

Open Water Bird Preserve

The Open Water Bird Preserve is a large pond east of Sunnyvale Baylands Park, west of Calabazas Creek, and south of the Guadalupe Slough. The Bay Trail runs run around it.

A great egret (left) and a great blue heron (right), feed in the northwest corner of the Open Water Bird Preserve, next to Sunnyvale Baylands Park.

On the west side of the pond are 3 members of the heron family: a great egret (top), a great blue heron (center), and a snowy egret (bottom).

The Bay Trail (left) runs along the north edge of the pond.

The Guadalupe Slough runs adjacent to the Bay Trail, north of it.

As the Bay Trail turns south at Calabazas Creek, a pier can be seen on San Tomas Aquino Creek just before its confluence with Calabazas Creek.

At the northeast corner of the pond above the levees, you can see the Coyote Hills on the left, the Alviso salt ponds in the middle, currently being restored to tidal flow, and the salt mounds at Newark.

This is a view of the northeast corner of the pond from the Bay Trail next to Calabazas Creek

This is the entrance to the Bay Trail. Sunnyvale Baylands Park is on the left. Calabazas Creek is on the right. Straight ahead is a storm water pumping plant. Behind it is the entrance to the Calabazas Creek Trail (see below).

Sunnyvale Baylands Park

Sunnyvale Baylands Park is a Santa Clara County Park operated by the City of Sunnyvale. It has 72 acres of developed parkland and 105 acres of seasonal protected wetland (park map). Gates are open from 8 am to 1/2 hour after sunsets. Parking fees are required from March through October. No dogs or balloons are allowed. For information and reservations, call 408-730-7751.

This is the Baylands Grove. The Baylands Trail runs through the line of trees beyond.

There is a large garden here irrigated by reclaimed water. There are a large number of plants and trees with identifying signs. The red trees above are Chinese pistache.

This is a view through the middle of the garden. The red trees on the left of the path are sweet gums. Chinese pistache are on the right.

The Baylands Trail runs through this line of trees.

A trail runs over a series of undulating hills, called the "Wave Walk," inspired by ocean waves.

This long viewing platform runs over the seasonal wetlands, which provide a habitat for the endangered salt marsh harvest mouse.

The pole structures are the Ropes Challenge Course, used by the Fremont Union High School District and are not for use by the general public.

The trail runs adjacent to freshwater and seasonal wetlands.

This path leads along the north side of the large lawn called the "Great Meadow." The Discovery Play Area is on the left. It is the largest of the 4 play areas in the park.

These metal pyramids mark the entrance to the Discovery Play Area. The giant fossil fish impression was made from a mold of a fossil at the California Academy of Sciences in San Francisco.

These are turtle sculptures in the Discovery Play Area.

The Meadow Trail runs along the south side of the Great Meadow. Several picnic areas are on the other side of the berms on the right.

A former road, now a path, leads east out of the park to the Bay Trail, which begins at Calabazas Creek (see above).

Harvey Marsh

Harvey Marsh is a large marsh area bounded by the Bay Trail on the south, Calabazas Creek on the west, San Tomas Aquino Creek on the east and north.

This is a view of the southwestern corner of the marsh from the Bay Trail.

This is a view looking east across the marsh from the trail next to Calabazas Creek.

This is a view looking at the north shore of the marsh. In the background are office buildings built on a restored landfill.

This is a view looking towards the southeast corner the marsh. The cars in the background are on Hwy 237.

This is the southeast corner of the pond from the gravel trail near the San Tomas Aquino Creek Trail entrance.

Calabazas Creek Trail

Sunnyvale's Calabazas Creek trail runs from the Bay Trail to Mission College Blvd. It is paved for 1.5 miles from Old Mountain View-Alviso Road to Mission College Blvd. The creek serves as the border between Santa Clara and Sunnyvale.

Just off the Bay Trail, the Calabazas Creek Trail is unpaved on both sides of the creek. This is the east side. The trail leads under Hwy 237.

This is the unpaved trail south of Hwy 237 Old Mountain View-Alviso Road is ahead. The trail passes under it and becomes a paved trail on the east bank of the creek.

This is the start of the paved trail south of Old Mountain View-Alviso Road, with a dirt trail next to it along the creekbed.

The paved trail ends at Tasman Drive, but begins on the other side. The VTA Light Rail runs in the middle of Tasman Drive, so the only way to safely cross is at the traffic lights at Patrick Henry Drive to the east or Reamwood Drive to the west. The Reamwood Light Trail station is nearby. A rough dirt trail leads under Tasman Drive, but it can be muddy in wet weather.

On the south side of Tasman Drive, the paved trail begins again, with a parallel dirt path along the creekbed.

This bridge crosses Calabazas Creek and leads to Fairwood Park and the John W. Christian Greenbelt.

The paved trail ends up ahead at Mission College Blvd.

John W. Christian Greenbelt

This is a map of the John W. Christian Greenbelt in Sunnyvale. The above picture is a thumbnail. Click on it for a high-resolution picture. The greenbelt is named after the late Sunnyvale Parks and Recreation director John W. Christian, who died in 1996. It was named in his honor in 2002. It is 80 feet wide and runs for 2.7 miles above the Hetch Hetchy Aqueduct. Maintenance access hatches for the twin aqueduct pipes are scattered along the greenbelt. The land is owned by the San Francisco Public Utilities Commission and is leased out to the city of Sunnyvale. On what was formerly a weed-covered right-of-way, landscaping and beautification was done between 1994 and 2001 to turn it into a linear park. It runs from Calabazas Creek, which forms Sunnyvale's border with Santa Clara, to Orchard Gardens Park, just before Mathilda Avenue.

This is Fairwood Park, with the ramp to the Calabazas Creek bridge in the background.

This section is between Lakewood Drive and Blazingwood Drive.

Entrance to the Lawrence Expressway overpass.

Looking back at the Lawrence Expressway overpass from the west end.

Note: the pictures below were taken in 2007:

Lakewood Park

This section is between Meadowlake Drive and Hidden Lake Drive.

This section is between Morse Avenue and Borregas Avenue.

This is Orchard Gardens Park, near the end of the greenbelt.


Web page developed 11/16/11, updated 11/11/14 by Ronald Horii