Archive for June, 2010

wiggle map Historic Watercourses of SF ~ Focus on the Wiggle & the Panhandle
Guest Speakers: Joel Pomerantz
7:30pm, Thursday, June 24th, 2010

Guest Speaker Joel Pomerantz gives us a tour of the the geology that shaped our city (and our bike rides!).

The Lower Haight once had lakes and streams. The valley had been the site of Spanish Mission trails and Ohlone trails before. Its zigzag of streets is known as the Wiggle by today’s bicyclists avoiding hills. Come glimpse the past and future of this fascinating urban valley with Joel Pomerantz, local geography researcher, founder of Thinkwalks.org and co-founder of the SF bicycle Coalition.

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Salt Pond Restoration

John Bourgeois project manager for the South Bay Salt Pond Restoration Project led us through the history, present and future of the salt ponds that line the southern edges of the Bay, looking forward to a time where we might restore some good portion of the 90% of tidal wetlands that they Bay has lost. The Bay and its wetlands have long been affected by humans. Salt ponds actually were formed naturally on the eastern shore of the Bay, and then reinforced by Native Americans.

Sediment from gold mining brought the first mass human driven change to the Bay. Followed by the diking of hundreds of thousands of acres for agriculture 1860-1930. Landfill still threatens the bay in some parts. Salt Ponds were industrialized in the 20s with machine driven levee building.

The restoration process began in 1999 with local organizations developing a roadmap for restoring wetlands. The plans became a little more concrete in 2003 when 15,100 acres were purchased from Cargill.

But the actual plan is a 50 year plan, with a phased implementation attempting to grapple with the many uncertainties of restoration: how to support the wildlife that is using the salt ponds as they currently are (like snowy plovers, driven there perhaps by pressure on beach habitats), sediment dynamics (the ponds are always sinking and need to be at the right elevation to support plant life), mercury methylation, invasive species, how to drum up and sustain public support (what public access should be allowed), how to sustain the infrastructure for the project, and the rising waters driven by climate change.

The phase one of the restoration is aiming to answer these questions. One pond complex (near the Dumbarton Bridge) attempts to leave habitat for species currently using the ponds (but not typical tidal marshland dwellers), one pond complex (by the Guadalupe River) is attempting to understand the process of mercury methylation better, one pond complex (The Alviso complex) has shown that restoration of sediment can be swift, and that birds and fish numbers have jumped dramatically. Already they’ve learned a ton, and they can see ways to make things better (opening the water onto the existing tidal channels still exist unused within the salt ponds).

The whole process is a long list of minute details with affecting a whole host of organizations both public and private, all levels of government and of course local politics. Seemingly obvious good things (reusing sediment dredged from shipping channels) can be hampered by environmental regulation (and complex logistics).
The money for the restoration has to come from somewhere.

In some ways, it seems amazing that any of this has happened at all. But the signs seem positive! To find out more you can visit http://www.southbayrestoration.org/

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