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Archive for July, 2011

Vanished Waters and the History of Mission Bay
Guest Speaker:  Chris Carlsson
7:30pm, Thursday, July 21st, 2011
Randall Musem, San Francisco, CA 

Chris Carlsson, Director of Shaping San Francisco, will tell the story of the gradual filling-in of a vast tidal cove. Mission Bay once was a tidal salt-marsh fed fresh water from meandering Mission Creek. Learn of the would-be settlers, speculators and visionary planners it has attracted over the last 130 years.

Find out more about Shaping San Francisco, at their website:
http://www.shapingsf.org/
You can find out more about Chris Carlsson on his sites: 
http://www.chriscarlsson.com/
http://www.nowtopians.com/

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Subtleties of the Subtidal

When Marilyn Latta first started presenting for the State Coastal Conservancy, on the Subtidal Habitat Goals Project, she had people in her audience ask: “I don’t understand what you mean about the sub-titles?” Sub-titles aside, it turns out that not many people understand much about the sub-tidal ecologies of the bay.

These are ecologies that exist in the water below the lowest median tide (the bay averages ~14ft deep, ~50ft at it’s deepest, but the majority of the bay is probably 6-8ft deep). For all practical purposes, that means they are invisible, hard to see, and difficult to study. And when all is said and done there is not much data to work from. First of all, even with good data about the way things are now, it is difficult to uncover data about what used to be.

As we know, they bay has changed drastically since 1848. Before the Spanish and the Gold Rush, the Ohlone of course also interacted with and managed the bay, but now there is only 5-10% of the original wetlands left. 1/3 of the bay has been filled in, and it is only by dint of people like Save the Bay, that more wasn’t done.

The Subtidal Habitat Goals Project aims to come up with a 50 year plan that is advisory. It is not regulatory, but hopes to help guide the policies of agencies working in the bay. The project has scientific goals — filling in the data gaps both current and historic; it has protection goals — maintaining the current quality and functions; and it has restoration targets – increase quality and size of certain habitats.

The project identifies 6 types of habitats: rock habitats (as what forms alcatraz); seaweeds (like Kelp beds off Angel Island); Soft substrate muds; Shellfish beds (oysters); artificial structures (piers, rip-rap, and pilings); and sand (a lot is mined from the bay to be used for concrete). The project identifies goals for all of these. Some have deeper mysteries (the source of sand in the bay is not understood for instance), some require a lot of work (removing the thousands of old creosote pilings that are leaching toxics into the bay), almost all of it requires patience and study.

The project is ambitious in both time and scope. We can hope that those who follow it its guidance can help bring us at the very least a greater understanding and appreciation of existing San Francisco Bay, if not helping restore in part the damage we have wrought.

More Information:

SFBaySubtidal.org
thewatershedproject.org/

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