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On my sixth bike ride of my quest to travel 350 miles of the San Francisco Bay Trail completed so far, I continued north along the east side of the Bay.  Hoping for needed rains in late October 2021 that could turn unpaved trails into impassable mud, I wondered if my ride on October 17 would be my last for a while.

To start this ride at the top half of Map 8 and bottom half of Map 9, I began at the Hayward Shoreline Interpretive Center (closed in 2021 due to Covid-19) situated on the north side of Highway 92 before it reaches the San Mateo Bridge.  There is plenty of parking on Breakwater Avenue in front of the Center.  The marshlands come right to the edge of the road.  I had a close view of a Great blue heron while I was unloading my bike.

On this part of the Bay Trail, heading north, the wetlands and marshes are on the right side of the trail and the shore of San Francisco Bay is on the left.  Although there are no signs explaining about the wooden, wind-powered Archimedes screw pumps — a type of spiral pump used to move water — I passed the best examples of this type of pump used in the salt harvesting process years ago, still completely intact, about a half mile north of the Interpretive Center.

The history in this area is about cross-Bay transport of harvested salt, agricultural goods and passengers in the 1800’s.  I followed the trail 7.7 miles north past San Leandro’s Marina Park to the San Leandro marina.

The Ohlone Indians lived in this area for thousands of years.  In 1769, Spanish soldiers arrived.  By the 1850’s, boat landings had been established to enable East Bay towns to deliver salt and agricultural goods across the Bay to the growing San Francisco metropolis.  Ships sailed back and forth with the tides twice a day, ferrying goods and passengers.  In 1854, John Johnson began harvesting salt in this area.  Other industries supported at this time were oyster farming and duck hunting to supply San Francisco restaurants.

In 1969, the Hayward Area Recreation and Park District (H.A.R.D.) began work to return the marshlands to tidal action, establish public trails and build the Interpretive Center.  The Hayward Regional Shoreline now consists of over 1800 acres of salt, fresh, and brackish water marshes.  Restoration of the 145-acre Hayward Marsh — the first marsh you will pass heading north from the Interpretive Center — was completed in 1985.

Even when the Interpretive Center is closed, one can still learn many things from the informational signs outside the building and along the trail.

For instance, over 7 million people live in this region.  When water from the surrounding watershed flows down onto the flatlands, it picks up oil, heavy metals, fertilizers, pesticides, even pet waste, from lawns, asphalt and concrete which it then carries into the Bay.  Salt marshes cleanse the Bay waters by removing pollutants from incoming tides.  Over 80% of the S.F. Bay marshlands are gone, a statistic affirming the importance of these restoration projects.

Or you can learn why the murky water in the S.F. Bay Estuary is a good thing:  The murk comes from suspended organic matter that makes the water a giant fishbowl of food.  Nutrients from the Delta, ocean and local streams flow into the Bay.  Plants and filter-feeding animals depend on this nutritional “broth,” found in the marshes, mudflats and Bay waters.

The salt marshes provide “a maze of hiding places for small fish and invertebrates,” until a striped bass or leopard shark passes through to snag a snack.

So many steps in the food chain are supported here:  the herons feed on small fish I’ve never heard of – stickleback, rainwater killifish, sculpin, gobies and gunnels – who come to feed on the invertebrates when the tide comes in.  At low tide, shorebirds snack on the clams, worms and other invertebrates, who have been stuffing themselves on a buffet of “organic ooze”:  mud, decaying matter, algae.

Salt marsh plants survive in this salty environment.  Red and green pickleweed are succulent plants that store excess salt in its tissues and are a favorite food of the salt marsh harvest mouse.  Pacific cordgrass, inundated with sea water during high tides, has special tissues that bring oxygen to its roots in the low-oxygen Bay mud.  Salt grass and coyote brush also thrive here.

After the Hayward Marsh, you’ll come to the Cogswell salt marsh.  Restoration of over 200 acres of former salt evaporation ponds was completed in 1980.  The project involved digging channels, creating islands, and breaching dikes to allow the Bay waters back in and restore natural tidal action.  The marsh provides habitat for 93 species of birds including great blue herons, snowy egrets, Great egrets, marbled gotwits, western sandpipers, American avocets, black-necked stilts, marsh wrens, least terns, willets, common yellowthroats, and northern harriers.  Some of these I can identify by sight, but not all of them by a long shot.  The marsh is named after Dr. Howard Cogswell (1916 – 2006), professor of environmental biology at Cal State Hayward, a man instrumental in planning and creation of these restored wetlands.

Riding from the Cogswell salt marsh west towards the Bay’s edge, one is offered several choices of bike trails.  Heading towards the water, one passes some hills of landfill on the right.  The trail bends right (north) at the water’s edge and continues north with the Bay waters on the west (left-hand) side and the marshes on the east (right-hand) side.  There are several foot bridges to allow one to cross various water channels such as Sulphur Creek and San Lorenzo Creek.

4.85 miles north of the Hayward Shoreline Interpretive Center, Roberts Landing — in the City of San Lorenzo – is where 406 acres of marshland have been restored.  Here, the project involved removing fill from former marshlands, lowering and removing dikes, and designing an intricate system of channels to re-enable tidal flow to all corners of the marsh.

In the 1800’s, the marshland here was dredged and filled to establish the site of the Roberts Landing Commercial Shipping Venture, a major shipping point for Alameda County (on the east side of the Bay) from 1851 to the 1870’s.  Flat-bottom scow schooners ferried people and products (hay, vegetables and fruit) from East Bay farms to San Francisco.  In the late 1860’s, the transcontinental railroad drove the venture out of business.  Trojan Powder Works diked and filled much of the marsh area from 1900 to 1963, manufacturing powder for ammunition used during World War I and explosives to build the Panama Canal.

It’s been a while since I have braved the elements for photography and bike adventures.  The weather report predicted a high of 64 degrees and 80% chance of rain on this mid-October Sunday.  I wore layers and brought a waterproof rain cover for my camera.  It was as cold as predicted, but the weather event turned out to be an incredibly high wind rather than rain.

Just a few miles south of San Leandro’s Marina Park, the wind from the north became so strong that many cyclists had to stop and walk their bikes.  There were times when I could barely keep my bike moving 4 miles per hour, where usual cruising speed for me on dirt is 10 or 11 mph.

The trail is paved for the last two and half miles to San Leandro’s Marina Park.  Despite the extraordinarily strong wind, the park was packed with family groups barbecuing, picnicking, and exploring an extension of land going out into the bay.  I hadn’t been near such a large congregation of people since the Covid-19 pandemic began.

There’s a fascination about the trail unfolding before you.  As long as there was finished Bay Trail to ride, I had to keep going.  It’s about exploration, discovery, adventure.  I knew I would have to retrace my wheel-steps for each mile I continued north.  But I couldn’t stop until I got to the San Leandro marina, not far beyond Marina Park, as far as I could go before the Bay Trail took a break.

On my return, heading south, I was hoping for wind at my back.  Instead, the wind shifted and came from the west, hitting me on the right side.  White caps on the Bay waters and along the shore confirmed how strong the wind was.  There were times when it pushed my bike a little to the left.  The trail was wide enough that this wasn’t an issue; however, it took all my concentration to maintain my balance.  Remember:  I ride more top-heavy than most cyclists with my 18-pound backpack.  The wind buffeted constantly without a break.  Was I tired at the end of the trip?  Well, yes, kind of like hiking from the bottom of the Grand Canyon to the top in a single day.

Still a few miles from the Hayward Interpretive Center and my car, but in desperate need of a rest, I stopped for a late lunch at Cogswell marsh area, which has a bench.  I could see the Center in the distance, encouraging me to continue.  I was wearing a fleece vest and a windbreaker.  The wind was so rough that I put on a second, hooded windbreaker over the first.  Once I was zipped up, hood covering my head and most of my face, I felt like I was safely inside a tent while the elements raged around me.  With lunch, water, and a bench to rest on, it was fun.

On the drive back, the wind was so strong that cars slowed down on I-880 south.  Concerned about my bike on the bike rack, I found a slow-moving truck and followed it home.  Another fun adventure!

The Hayward Shoreline Interpretive Center

The Hayward Shoreline Interpretive Center

Beginning the ride.

Close-up of Archmides screw pump used during salt harvesting — no description on any signs in this area.

Green pickleweed



View from Cogswell Marsh

Trail choices at Cogswell marsh.  Go left to get to the Bay waters.

I think these are marbled gotwits – all standing on one leg.

Closer view of the marbled gotwits.

Paved trail; riding into brutal winds from the north, heading into San Leandro’s Marina Park.

Land with walking trail extends out from Marina Park into the Bay.

Heading back (south).

Strong west wind raising white caps on the Bay’s waters.

Low tide reveals mudflats.

Seen while unloading my bike: great blue heron, white egret, Archimedes screw pump in the distance.


One of several Archimedes screw pumps in the distance.

Snowy egret

Red pickleweed


Foot bridge to cross Sulphur Creek


San Mateo Bridge in the distance.

Marshlands on the right (east) side of the trail.


Roberts Landing

Info sign (and my bike) at Roberts Landing.

San Leandro Marina

San Leandro Marina

White caps higher; strong wind pushing my bike left.

I can see the Hayward Interpretive Center from the bench at Cogswell Marsh; nearing the end of today’s ride.