Sunnyvale Water Pollution Control Plant (Fall/Winter):
Ducks for Days
by Mike Ambrose
You wouldn’t think that sewage treatment would be a travel-worthy destination, but Sunnyvale Water Pollution Control Plant’s large variety of waterfowl and passerines is well worth a trip. Whether you’re looking for a 100-yard stroll from the car or a 4-mile hike, this spot provides excellent views of a large variety of bird species, all in a beautiful bay-front environment.
Trip Covers: October - March
Key Birds: Cinnamon Teal, Northern Shoveler, Sora, Common Gallinule, Green Heron
View of Radar Tower by Eve Meier
How to Bird
Sunnyvale WPCP consists of two ponds - descriptively named East Pond and West Pond - which are bordered by the Moffett Channel to the east and Guadalupe Slough to the north. Walking the longest loop around both ponds clocks in at around 4 miles, or you can get nice views of Moffett Channel and Moffett Bay just beyond the parking lot - or anything in between.
Access the Bay Trail from the street parking on West Carribean Drive (shown on the interactive map). Follow the trail out towards the bay, keeping Moffett Channel on your right. Don’t take the trail on the east side of Moffett Channel - this will take you to Salt Pond A4, not covered by this field trip.
Wide gravel trail with Moffett Channel on the right.
Moffett Channel often has a nice variety of birds - look for Black Phoebe, ducks (including Mallard and Green-winged Teal), and herons and egrets. One special bird which can make an appearance is Green Heron, but it’s often very well camouflaged. Your best chance for seeing this elusive bird is when the creek veers sharply to the right, around 500 feet from the parking lot (#1 on the interactive map). Carefully scan both banks and you may be rewarded with a view of this beautiful heron. There are also sometimes blackbirds in the reeds here, and sometimes you’ll be rewarded with the incredible calls of Great-tailed Grackle.
Green Heron by Dwight Agan
Once you’ve reached this first bend in the Moffett Channel, you’ll also have some nice views of Moffett Bay (#2 on map). At this time of year, the bay can be full of ducks. Scan through and look for Ruddy Duck, Northern Shoveler, Bufflehead, Gadwall, American Wigeon, and Canvasback. Other ducks sometimes also appear in this bay, like Lesser and Greater Scaup.
Female Northern Shoveler by Sushanta Bhandarkar
Follow the right turn in the trail to continue along Moffett Channel and head towards the East and West Pond. The next 0.5 miles is a terrific time to listen for rails, especially Sora (#3 on map). Listen for their distinctive “whinny” call. You can also scan the telephone wires for raptors - Red-tailed Hawk, White-tailed Kite, and Northern Harrier are all common hunters in the marshes here.
Common Gallinule by Raminder Bajwa
Shortly before the radar tower (#4 on map), the trail splits into several paths (all shown on the interactive map). All of them provide excellent birding opportunities, so you can’t go wrong! If you’re a first-time visitor, though, I recommend turning right following the path that runs along the edge of the East Pond, keeping the East Pond to your left and a small channel to your right. Make sure to keep a constant eye on that channel - it’s one of the best places in the county to see Sora, which occasionally make brief trips from the safety of the reeds and allow furtive views. It’s also a consistent place to find Common Gallinule, and there are occasionally Wilson’s Snipe hiding along the banks (#5 on map). Further along the path when the water deepens, you can frequently spot Cinnamon Teal and Blue-winged Teal. And don’t neglect the pond itself, which is often home to many hundreds of wintering ducks. You’ll probably start to recognize many that you saw in Moffett Bay, but be on the lookout for less common ducks as well, including Redhead and Eurasian Wigeon.
Cinnamon Teal by Diane McCoy
At this point, you’ll have a good handle of the birds that you’re likely to see throughout the rest of the Water Pollution Control Plant, so you can forge your own path! With many miles of trails and tons more species than can fit in a quick self-guided trip, you’ll be finding new and wonderful birds across many return trips.
Ready for More? Check out Adam Burnett’s excellent self-guided field trip to Pond A4 (Winter): A Wintertime South Bay Birding Sampler, another part of Sunnyvale WPCP. If you’re exploring this area in summertime, check out the Sunnyvale WPCP (Summer): Phalaropes in the East Pond.
Interactive Map
Directions: From CA-237 in Sunnyvale, exit Lawrence Expy/Caribbean Dr. Continue onto Caribbean Dr. In 1.2 miles park along E Caribbean Dr (just past Borregas Ave). Access the Bay Trail from here (shown on the interactive map). Latitude/Longitude: 37.417672, -122.019018
Parking: paved parking, ADA compliant spots available
Fees: None
Public Transportation: The Borregas Light Rail Station and the bus stop at the intersection of Java Drive and Borregas Avenue are each 0.6 mile from the trailhead on West Caribbean Drive next to the parking area.
Trail Hours: Sunrise to sunset
Facilities: Wheelchair accessible porta-potty, often not pleasant
Trip Mileage: Up to you - anywhere from 500ft to 4mi
Trail Conditions: dirt road in full sun, can be crowded at peak times
Accessibility: All paths are flat and wide but not paved. The parking area is paved but good birding doesn’t start until you’re onto the unpaved dirt roads.
Bikes: This is a great trip to do by bike.
Dogs: Dogs allowed on 6-ft leash
More Information
Sunnyvale WPCP Trail Map
eBird hotspot: General Hotspot, West Pond, East Pond
All About Birds: Green Heron and Common Gallinule (watch out for tricky non-adult plumage!)
More Resources
For more trips like this one, visit Self-Guided Field Trips.
Visit the SCVAS Birding Resources page for more information on where to bird, our birding community, bird identification resources and more.
Read “What to Look for Now” by SCVAS Executive Director Matthew Dodder.
Banner Photo Credit: Redheads by Dave Zittin
Last Updated: 5/02/2022
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