On an overcast Sunday, D. and I returned to the alien world of the nearby abandoned salt crystallization ponds at the edge of San Francisco Bay. When we looked at them a month ago, the remaining ponds were a deep orange color, and one still had that mysterious black void in it. We returned to check on the void this month, and I took some pics of what we saw.
The first thing we notice is that the water is no longer orange; it is now a tawny yellow.
The different colors of salt ponds indicate their salinity levels. When the brine is fully saturated, the salt-loving alga Dunaliella proliferates and turns the ponds brilliant vermillion. The paler color here indicates the salinity has changed since last month.
The brine is very shallow and even small objects lying in them stick out, encrusted with salt.
There are Otala lactea and Theba pisana snails living in the brush on the nearby levee, and their shells can be found all over the salty, rock-hard mud.
Veins of dirt on the bottom create marble-like patterns in the ponds.
The dirt was probably washed in from recent rains. The rain likely also diluted the salinity and changed the color of the brine.
Reflections in the brine. Yes, it's a power line.
This severe and neglected landscape is a place where the dead and discarded collect.
The brine is completely saturated. Salt crystals form in a film on the pond surface, dropping to the bottom when they grow heavy enough to overcome the water's surface tension.
Looking back toward the disused pump house.
We reach the section of the pond that has the bizarre 25' long black void. The brine is still too murky to tell anything about it at all. It is not an optical illusion or a reflection of something else in the water. It is not a deep hole in the pond. It is a mystery.
At the eastern edge of the crystallization pond, we climb the levee and behold another salt pond.
This one still has deep red brine, and black voids of its own.
A board seems to float above the pond on skirt of crystallized salt.
The salt evaporation and crystallization process can take 5 years. When done, the bed of salt created is a foot deep.
The water is so saline that nothing else but Dunaliella alga can live in or around it, creating an almost sterile alien landscape where life can be very harsh.
Salt crystallizes around any foreign object in the pond.
Tiny islands of salt protrude above the surface.
An archipelago of salt.
A beach of salt.
This severe landscape verges on the abstract.
Looking northeast and southeast.
Near the boundary of Bayfront Park, we find a lost baseball cap in the pickleweed.
Reflections in the salt pond.
This is a gate structure on a levee, where the movement of brine between ponds was controlled back when the salt ponds were operational.
At one time all of the levee was fenced off.
The strange environment has an occasional cryptic signpost.
The answer to everything.
Who knew it would be right here in an abandoned salt pond?
The clouds darken, but, somehow, rain holds off.
We climb another levee and follow a trail in adjoining Bayfront Park. It is not obvious the park used to be a landfill, but there are occasional indications.
The trail turns a corner and we are returned to the world of life again. We go past a lagoon open to the tides, thriving with life, a stark contrast to the harsh alien landscapes of the salt ponds.