Sunnyvale Baylands

Part 2 - The Baylands Ponds

West Ponds
East Pond

Go to Part 1 - The Bay Trail and Hills
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


There are two huge pond complexes at the Sunnyvale Baylands. The west ponds, which are west of the Moffett Channel, consist of several interconnected ponds and channels. The east pond, east of the Moffett Channel, is a salt evaporation pond. While both sets of ponds are accessible to the public, only the ponds to the west have developed and maintained trails. The slightly smaller pond to the east has a wide levee trail around it, but no trail amenities yet. The southwest section of the levee tends to be over-grown with weeds. However, the advantage of the eastern pond is that  it smells better than the western ponds. The western ponds are a complex of channels, pipes, aerators, dams, and pump stations. It is an active part of the water treatment system. It has a noticeable, but tolerable smell in places, but it is a chemical chlorine smell, somewhat like a swimming pool. Ironically, the strongest-smelling portion of the pond is where it is adjacent to a salt pond, which has a sulfur smell during certain times of the year from decaying algae.

Access Information

Both of the ponds can be accessed from the Bay Trail in the Sunnyvale Baylands, but from different parts. The west ponds are most easily reached from the Sunnyvale Water Pollution Control Plant at the end of Carl Road (see the directions in Part 1). The east pond is accessible from the Bay Trail. The east end is closest to the East Sunnyvale Channel next to the Twin Creeks Sports Complex. Until the levee trails along the East Sunnyvale Channel are fully open, the closest access point is from Sunnyvale Baylands Park. The west end of the trail around the East pond is closest to the trailhead at the water pollution control plant. See Part 1.

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The Sunnyvale Bayland ponds and levees are excellent for bird-watching. Huge flocks of birds of all types use the waters and rest on the levees here. Below are some examples:




See here for a list of birds at the Sunnyvale Baylands. See here for more info. on bird-watching in the Sunnyvale Baylands.

West Ponds

The ponds on the west side of Moffett Channel are used as oxidation ponds for treated wastewater. These were 440 acres of salt ponds until they were purchased in 1962 for water treatment. There are several parallel and crossing levees through the ponds. However, there is only one entry point to the trails. To reach them, start at the Bay Trail entrance at the end of Carl Road at the Sunnyvale Water Pollution Control Plant.

Cross over the West Sunnyvale Channel and turn right onto the trail along the west bank of the channel. Continue past the Bay Trail heading west to Lockheed Martin. The mileage readings begin here.

The West Sunnyvale Channel turns to the right.

The trail follows the channel to the right. On the left is a salt pond channel that carries brine from the salt ponds near Moffett Field to the east salt pond at the Sunnyvale Baylands. At 0.1 miles, a huge concrete pipe runs along this salt pond channel, carrying wastewater between the water treatment plant and the oxidation ponds. The trail and the channel turn to the left. There's a bench here, the first of several around the water treatment ponds, a good indication that this is a public recreational trail. The channel on the right becomes the Moffett Channel. It carries the outflow from the water pollution control plant, which is freshwater, to the Guadalupe Slough.  Freshwater marsh plants line the channel. Follow the trail to the left.

This is a view looking west. The salt pond channel is in the foreground. The levee to the left of it separates it from treated wastewater. The pier on the levee has pumps for the wastewater.

The trail here is a wide gravel road. It follows the salt pond channel to where it dead ends at the levees around the water treatment ponds. The tower ahead is the radar for Moffett Field. A major junction of several levees and waterways is ahead. There are actually 6 possible levees trails that you could take.

After you pass by the end of the salt pond channel, at 0.4 miles, the levee there separates it from a wastewater channel. This levee will be used on the return trip. Looking down this wastewater channel, you may see some operating aerators. If they are operating, and the wind is blowing strongly down the Bay, you may want to take the next levee over to the west on the return trip. Keep this is mind. The aerators are portable. There are power stations for aerators all over the water treatment ponds, but this is where they seem to be the most active.

The wastewater channel ends at a dam. The dam controls the flow from the channel beyond it. You have a choice of several levee trails here. For this trip, stay on the right and go around the Moffett Field radar tower at 0.5 miles.

You will be following along the outer perimeter of the wastewater ponds. An inner levee produces a channel along this edge of the pond. This inner levee trail is an accessible alternate route. The marsh to the right along the edge of the Moffett Channel is full of bulrushes. At 0.6 miles is another bench. You can see the east salt pond on the other side of the Moffett Channel.

This is a view looking across the channel on the left, with the large treatment pond beyond. In the distance are the buildings of Lockheed Martin and Moffett Field.

At 0.9 miles is another bench. At 1.1 miles, the trail begins to turn left at the corner of the pond. On the right you begin to see the confluence of the Moffett Channel and the Guadalupe Slough. The Guadalupe Slough flows out to the Bay to the West. The outer levee trail begins to follow it.

This is a view looking back towards the Moffett Tower at 1.2 miles. The inner levee may be covered with birds using it as a resting place. The trail makes a sharp left turn at the corner of the pond. The inner levee trail joins up with the main trail here.

The trail runs in a straight line along the edge of the large treatment pond, with the broad marshes along the Guadalupe Slough to the right. At 1.4 miles is another bench.

Soon another levee trail joins up with the main trail at 1.7 miles. This levee leads back to the dam seen near the radar station. An inner levee can be seen to the right of this levee, which leads to the other side of the dam, but is not accessible here.

The trail begins to follow the curve of the Guadalupe Slough, barely visible beyond the marsh. Soon the slough comes closer to the trail and can be easily seen from it.

At high tide, the Guadalupe Slough is a wide waterway. This is a view looking back along it.

The wide Guadalupe Slough comes right up next to the trail, separated by a narrow margin of marsh plants.

The slough widens as it curves to the right. Ahead are the NASA boat docks.

This is a view south across the water treatment channel and pond. The treatment pond beyond the nearby channel is huge. It's the largest pond in the Sunnyvale Baylands.

This is a view across the Guadalupe Slough. Beyond it is a salt pond that is currently closed to public access.

There is another bench here at 2.2 miles, a short distance from the NASA docks.

On the left side of the trail at 2.3 miles is a fenced-off pier and pumping complex.

At the corner of the pond at 2.4 miles, you can see the NASA boat docks on the Guadalupe Slough. A fence blocks access to the area. Don't trespass here.

The trail makes a left turn at the corner of the pond and the end of the channel. Here you can access the inner levee that leads back to the dam.

On the immediate right is a salt pond channel. It may be dry in the summer. A sign apologizes for the sulfur smell which comes from decaying algae in the salt pond. On the west side of this channel is the road from the NASA boat docks to the Moffett Field Golf Course. It is off-limits to unauthorized personnel. To the west of this is a huge salt pond, bigger than the Sunnyvale water treatment ponds. Duck blinds can be seen in the pond. This is Cargill property and currently off-limits.

The dry salt pond channel ends at a levee at 2.7 miles. The levee connects to the NASA boat dock road, but it is fenced off to prevent access. Beyond it is another salt pond channel. This area may be filled with large flocks of seagulls.  In the distance are the giant hangars at Moffett Field.

After passing the levee, the second salt pond channel is on the right. This one is active. It connects the salt pond by Moffett Field to the salt pond on the east side of the Sunnyvale Baylands.

Looking west, a bridge under the NASA boat dock road allows water to flow between the salt pond beyond and the channel in the foreground.

The trail passes by a levee on the north side of a wastewater channel, which begins here. Recalling the aerators at the beginning of the tour, this channel leads to those aerators. The north levee runs on the upwind side of the aerators. Take this if you wish. Otherwise, keep going on the main trail.

The main trail turns left at 3.0 miles and runs between the wastewater channel and the salt pond channel.

Old broken catwalks cross through the salt pond channel to provide service access to power line towers.

This is a view looking north across the wastewater channel at the inner levee and the large pond beyond.

This is a view of the wastewater channel, with the inner levee on the left. The landfill hills appear on the right.

At the point where the inner levee and outer levees make a left turn at 4.0 miles, there is a pumping pier on the outer levee extending into the channel.

Ahead on the main trail are the aerators. If they are turned on, hold your nose and hurry past them. You will reach the main trail junction near the radar station at 4.2 miles. Turn right and return to the trailhead. The total distance from the trailhead, around the ponds via the outer trail, and back to the trailhead is about 4.7 miles. If you take the inner levees, it will be shorter.

East Salt Pond

On the east side of the Sunnyvale Baylands is a huge salt pond. Plans are in the works to restore this 320-acre pond to tidal flow. According to the current map of the Baylands, there is no trail around this salt pond. In reality, there is a trail along the top of the levee around the pond. People use it all the time, and there are no signs (as of this writing) prohibiting its use. However, until this becomes an official trail, if ever, trail access and maintenance may not be consistent. There are no benches or trash cans on this trail. Though most of the trail is flat, smooth, and in good condition, the short section near the southwest end tends to get over-grown with weeds, making passage difficult. This may change in the future, but be aware of it. The tour around the east salt pond begins near the southeast end and runs counter-clockwise. The access point is at the bridge over the East Sunnyvale Channel. See Part 1 for directions.

At the bridge over the East Sunnyvale Channel, take the levee trail east on the north side of the bridge. The mileage readings will begin here.

This segment of the trail runs long and straight between the edge of the salt pond and the channel.

In the pond is a long levee that forms a channel along the edge of the pond.

Ahead, the salt pond channel dead ends at the corner of the pond. Near here is a pumphouse.

At 0.3 miles, the East Sunnyvale Channel makes a loop to the right. The trail makes a semi-circular loop to follow the channel. At the outer end of the loop, the channel joins the Guadalupe Slough. The trail then begins to follow the slough.

At 0.4 miles, the trail drops down into a basin. Near the pumphouse, it turns right and climbs up to the levee along the Guadalupe Slough. At 0.5 miles, a salt pond pipeline connects this salt pond with the one to the east across the Guadalupe Slough. That salt pond is off-limits to the public.

The Guadalupe Slough channel is surrounded by tall marsh plants. Large flocks of egrets and herons can be often seen resting in them.

At 0.6 miles, the trail straightens out. The trail here is a wide dirt levee trail built on graded bay mud.

The trail comes closest to the Guadalupe Slough at 0.7 miles. The slough begins to widen out.

The salt pond is lined with pickleweed and grass.

A wide marsh separates the levee from the Guadalupe Slough

The river makes several meandering bends, which the trail follows. As it does, you can catch glimpses of the large off-limits salt pond beyond the other side of the slough. You can see an old building on the pond.

The east salt pond is a huge expanse of open water. The recycling center and water treatment plant can be seen on the other side.

The trail straightens out. You can see the corner of the pond ahead.

At 1.7 miles, you reach the northwest corner of the pond. The Moffett Channel can be seen flowing into the Guadalupe Slough.

The path turns left and runs between the salt pond and the Moffett Channel. It begins to become narrower. The water in the salt pond here at the left of the trail is clear as this shore get little turbulence from wind waves. Ahead on the right is the Moffett Field radar tower.

The banks of the Moffett Channel are heavily vegetated with bulrushes that may be filled with herons and egrets.

Near the southwest corner of the pond at 2.2 miles is a valve connecting the salt pond to the channel near the west ponds. The salt pond water flows through a pipe that crosses under the Moffett Channel. Here the inner levee begins, forming the channel along the edge of the salt pond. You are likely to see herons and egrets stalking their food here.

The trail turns left at 2.3 miles. To the south, you can look down the Moffett Channel and see its confluence with the West Sunnyvale Channel. The trail turns to follow the reed-lined West Sunnyvale Channel and runs along a levee that is covered with heavy weed growth. If these weeds have not been cut, it makes traveling along this last segment difficult. Fortunately, this last segment is short.

This trail ends up at the Bay Trail by the SMaRT recycling center at 2.5 miles. (This is a view looking back along the east pond trail from the Bay Trail.) Continue east on the Bay Trail to return to the starting point at the East Sunnyvale Channel Bridge at 2.8 miles.

Go to Part 1 - The Bay Trail and Hills
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

Developed: 10/28/2001 by Ronald Horii
Information and opinions here are the responsibility of the author.