On Sunday D. and I went to the Alameda Creek Regional Trail in the East Bay, and I took some pics.
We join the trail where Alameda Creek is contained in a wide, deep flood control channel, lined with large rocks, almost choked with vegetation. Creek access is forbidden and dangerous. In late summer the flow is very low.
The I-880 overpass.
The creek used to flood the area below Niles Canyon regularly until it was tamed and channelized.
A great blue heron hunts in the bed of the channel.
In places, the channel is some 200 feet wide and over 2 stories deep.
The channel as it approaches the Coyote Hills.
Near Coyote Hills Regional Park, on the other side of the trail we see the DUST (Demonstration Urban Stormwater Treatment) Marsh. Created in 1983 as an experimental 55-acre freshwater marsh, its purpose is to use marsh plants and organisms to remove toxins from the stormwater runoff from residential and commercial areas.
Once we round the Coyote Hills, we are on the approach to San Francisco Bay. The creek is in a natural channel now.
At the side of the creek here we see the remnants of an Archimedes screw, once used to move water from one salt evaporation pond to another. The mechanism and the blades that caught the wind to drive it are long gone.
We are very close to the Bay. Everything is flat and wide open.
Across the Bay, the fog bank hovers over the Coast Range behind the San Mateo Bridge.
A pod of pelicans fishes in a salt pond across the trail from the creek.
With their brilliant white plumage, they bring to mind little meringues floating on the water.
Open water is in sight.
The end of the trail, where the creek's fresh water mixes with the bay's salt. This meeting between the creek and the bay creates a vast ecosystem known as an estuary. San Francisco Bay is the largest estuary along the Pacific Coast. The organisms living in the estuary survive the challenges of a constantly changing environment that ranges from dry to flooded and from fresh to saline. This helps to create the enormous diversity of life in this region.
Someone didn't moor their boat properly. The Christina Maria is stranded out here at the levee.
Alas, a romance on the rocks. Literally: this heart has been cast up here amid a jumble of rocks, dirt and driftwood.
Someone drew some art on the trail pavement along a stretch west of I-880. Here's a smiley face.
Here's a smiley fish.
And here's another smiley face. A friendly trail.