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Sky Phenomena
Guest Speaker: Joe Jordan
7:30pm, Thursday, Nov 20th, 2014
FREE at the Randall Museum, 199 Museum Way, San Francisco, CA 

Rainbow above the golden gate

Joe Jordan will come back with new material after having really wowed and inspired our audience with his slides on this topic in 1997.

Joe will show pictures of all kinds of atmospheric phenomena, including rainbows, haloes, glories, aurorae, coronae, mirages,
and the legendary (but real) “green flash”.   He’ll bring along some hands-on 3-D models (to go along with his descriptions
and explanations) that might help us understand what causes some of these things, and where and when to watch for them.

As an added treat, Joe will regale us with information and stories on a recent focus of his — the science, technology and politics, behind clean energy (“sky power to the people” — see his TED talk on it – shown below!) — including the scientific basis for a big public-art sculpture idea.

(notes by Joel) Geologist and plate tectonics animator Tanya Atwater spoke to us October 16, 2014. She gave us her presentation called Living in the Plate Boundary and Through the Ice Ages.

The presentation was largely based on diagrammatic animation videos which these notes cannot describe. But you can see them yourself on Atwater’s website  (or you can Google Atwater animations). I apologize that I wasn’t as able to take notes as usual since my eyes were up on the video screen a lot.

The surface of the earth is made of plates floating on (and diving down thousands of miles into) the earth’s molten mantle, which is always flowing.

When you look at the animation of the continents coming into their present formation, India seems to move faster than the rest. This is partly due to the size. Smaller means it can move faster. Of course the speeds are all pretty slow, taking many millions of years. (Speeds are similar to how quickly a fingernail grows, according to Julian’s talk back in July.)

The Himalayas are uplift (crumpling and wrinkling of the plate that pushes the surface up). This is due to the direct-hit crunching of the Indian plate against the plate to its north.

The Pacific Plate is the largest plate, taking up almost 1/3 of the surface of the earth. It’s being dragged past the North American Plate to the NW, scraping against it and at the same time leaving bits behind along the edge.

The area west of North America has been for a long time (until recently) made up of three ocean plates. Ocean plates are formed by spreading mid ocean rifts where mantle magma wells up in the gap. (Continental plates are formed by uplift, by volcanos, by wind and glacial deposits, etc.) The two plates on the east side of the rift zone have flowed under the Americas now (a process called subduction). There’s a tiny bit left of one (Juan de Fuca Plate) in Oregon and North California Coastal waters and a little (of the Farallones Plate) near Central America.

As the rift spreads, the Pacific Plate gets bigger on its east side faster than it moves northwest. That means it grows and seems to come closer while in fact it is moving away. The direction of movement is not directly away, but scraping NW along our coast, pulling our coast out and stretching the North American continent. That’s why the high areas that used to be Utah and Nevada had room to collapse and fall over becoming the basin and range provinces with lots of gaps between high ridges. It’s also why the Gulf of California has opened up.

The San Andreas

Tanya’s graduate thesis was to try and figure out the San Andreas Fault, which turns out to be a unique fault over the whole earth.

If a slipping fault is a perfect line in the direction of slip, it has no gaps or places that push against each other (forming wrinkles, i.e. hills). But in reality, all places have some kinks, so there are hills and gaps formed.

Pinnacles Park in California has a very different kind of volcanic rock. Rocks the same have been found hundreds of kilometers away so we know that one side of the slipping fault moved that far since the eruption.

Bodega Head has granite that has moved up from Southern California, 500 km, as do a few other spots on the Northern California coast.

About 25% of the motion of the fault’s energy is spread into the Tahoe region in smaller stresses. In 10 million years, there will be an ocean alongside Las Vegas, because the Pacific Plate will have dragged what is now California away, probably.

Subduction

Before the San Andreas, we had a subduction zone as the ocean rift pushed plates under us. The mid ocean ridge where the spreading areas were is now mostly under us. A subduction pretty much has to be along a straight line. When the subduction hits the melting point (not from friction but from the internal heat of the earth) it bubbles up through the plate above it. That is why there are volcanos in the Cascade Mountain Range. It’s the Juan De Fuca Plate coming back up. Some is trapped under and that becomes granite. Some makes it to the surface and is lava. That lava flowed to the coast and was crumbled and tossed into a mixer of rocks, seawater, etc, some of which was dragged back down by the subduction to enter the whole cycle again and again. Meanwhile, some of the rubble of this cycle is left on the edge of the North American Plate. This is the accretionary wedge.

Other geographical features

The Great Valley (a.k.a Central Valley, San Joaquin Valley, etc.) is the collected debris of the volcanos and cycles of subduction at the edge of the continent. The land west of it (the coast range) is the uplifted part of that debris (cause by bends in the slipping fault pushing mountains up) mixed with melange of things dragged along from elsewhere. The melange is blue schist and chert and all sorts of stuff.

The Transverse Ranges (Tehachapies) that curl toward the coast are granite like the Sierra Range, but the farther south you go the more deeply eroded it is, so the farther under the formation you are looking. The granite in places like Joshua Tree Park are not smoothed into canyons like the Sierra’s because there were no glaciers to scrapes and smooth them. They formed rounded boulders instead.

The L.A. basin is deep and filled with mud.

Between Santa Barbara and San Diego there was a break and a gap opened. The land that was there got pulled and rotated. It is now the block of material that the Channel Islands and Santa Barbara sit on. It tumbled and was rotated to its current position by the two plates grinding past one another within a gap where the coast was pulled out allowing for rotation. Geologists can tell this is so, even though it is unlikely, because the rocks formed with their magnetism lining up with the poles. Now it points east in all those areas, so they know by paleomagnetism studies that the whole section pulled apart and rotated.

Ice Age

The present sea level is about as it has been since the last ice age ended 6,000 years ago. It’s melt from the ice age glaciers. The maximum of the ice age was about 17,000 years ago after tens of thousands of years of ice age. We are now in an interglacial period. The previous one was about 100,000 years ago, and they happened in the past about every 100,000 years. Ice ages always come on slowly and end quickly.

As the glaciers melt quickly, the sea level rises a lot. (For the most recent, between 300 and 400 feet all around the world at once.) Each place where a sea level remained a while, the wave action cuts a terrace on the edge of the continent. By the time the sea level goes gradually down and then quickly back up the next time, the continent has risen some distance, so the next wave terrace is below the old ones. This eventually forms a stair-step coast line. The older steps are more eroded but they are highly visible even to the untrained eye.

If there is a lot of sand in the waves, it takes up the wave energy, but if not, the energy cuts new terraces.

There was so much more she said!

Ice Plants, Mattress Wireweed & Other Onslaughts
Guest Speaker: Lew Stringer
7:30pm, Thursday, Jan 15th, 2015
FREE at the Randall Museum, 199 Museum Way, San Francisco, CA 

Have you seen how much of our coastal parkland is now covered in succulent ground cover, hardy New Zealand vines, and just too many highly invasive species? Come hear Lew give us the low down on ground cover invasive plants. He’s been working with the Presidio Trust, and before that the Golden Gate National Recreation Area, to develop strategies to manage the various species that would take everything over if they managed themselves.

(Notes by Joel)

John Scarpulla talked to us September 18th, 2014, about the Living Machine at the Public Utilities Commission (PUC) building SF Headquarters. John is a project manager, not an engineer. Very informative.

PUC headquarters: a well built building. Safe place in a quake. Command center for emergency operations. Features: Rainwater harvesting in preschool play area made of spongey material that’s permeable. Collects the water there and uses it to irrigate street trees.

The system called the Living Machine, a million and a half gallons per year. Not a large project compared to the 65 million gallons per **day** that the SF sewage treatment plants treat, but an example, a demonstration site. And a chance to test processes, including permits and ordinances. Wastewater treatment out in the open. Integrate technology into the neighborhood providing green in tenderloin.

Building is separately “dual plumbed” for potable water from the Hetch Hetchy system and wastewater internal system.

Water flows from primary tank to flow equalization tank to wetlands to building in a 48 hour loop. Flows from 7 to 7; none at night or weekend. Wetlands are in sidewalk, lobby and then the water cycles through the basement systerms.

Primary treatment tank is called and looks like a big “hotdog” and they needed a permit for that because it goes under the sidewalk.

First, a trash chamber separates things that shouldn’t have been flushed.

Second, a settling chamber removes a lot of the settleable and floatable solids. The solids are processed elsewhere. They don’t manage solids on site because the site’s too small.

The cycle is in waves, sending batches into the system with a 3000 gallon equalization tank. Recirculating tank for water available to go back to toilets is 6000 gallons. Wastewater treatment of 5000 gallons a day.

Nature wetlands, etc. process water by slowing the flow and cleaning the water but this speeds it up while cleaning it.

One way they do that is with “tidal” action. Water fills and then goes down like a tide every 58 minutes. Process quickly because the plant roots and soils are exposed to an influx of oxygen when water is low and organic microorganisms when the water is up. Most of the solids that were suspended in the water are removed by this process. Both aerobic and anaerobic bacteria involved. Self sustaining.

Ramped up population at the beginning, two years ago: Plants got inoculated then synthetic wastewater (milk solids and ammonia) were fed to it until real nutrients came into the system when building opened. Gradually reducing synthetic wastewater as human use increased so microorganisms kept stabilized.

Off gassing of nitrogen tells what population of microorganisms is like.

Department of Public Health (DPH) required wastewater to stay six inches below topsoil, so there are overflow vents to the sewer system preventing sidewalk overflows. Four inches under there’s a mesh to keep people from digging into the wastewater. No odors because subsurface vent sucks in and odors are emitted through a rooftop carbon filter scrubber.

Reasons particular plants were picked: Marsh plants can stand water in their roots all day every day. Must be tolerant of high nutrient levels. North side gets no sun. Plants have to be able to survive those conditions.

Landscape architect new to this but experienced engineer that has done this system before.

Batch sizes depend on whether it’s raining and day of the week. People are not in the building weekends.

Golden Gate Avenue side is the tidal flow wetland. Polk is the vertical flow wetland: one pass through of the water there first to cell 2a, then down hill to cell 2b. Light tan tint to the water after going through the wetlands. The filtering is then complete so it goes into the interior lobby plants which are a different plant pallet with species that like more sun.

“Acre Café” is in the lobby area twenty feet from the treatment.

There are pumps in addition to gravity. Twenty percent of California’s electrical and 30 percent of natural gas in the state is used for water systems. Living machine uses 75 to 90 percent less power than other systems available because they all use force through a membrane and this does not.

The water gets disinfected with UV light and a little chlorine in tablet form like a pool before it goes to the toilets again. There is one building in Toronto trying something similar that decided not to do chemical treatment and the mold growth became a public health and operational concern.

The system is entirely operated by computer from control room or from desktop computer or smartphone. Fully automated.

Aqua Nova specializes in wetlands.

DPW (Public Works) was involved because it was a large public building being built. Permits: No regulatory rules existed for this so they had to create some. DPH and DBI (Department of Building Inspection) and PUC signed letter of agreement. Will test yearly and inspect plus send results to DPH. Choloform, Turbidity, Oxygen load, etc. In the system itself, sampling is the biggest time draw. Otherwise little for humans to do to maintain it, oh except: Maintenance is big because warmth attracts sleeping, then there’s vandalism. People steal the plants and they have to be replaced.

Inreach wasn’t done as well as they wanted. For an agency of 2300 only about a dozen people came to the one inreach meeting. Outreach was good though.

Project purpose: help ask How can we get other building designers to rethink? In large residential, about half is nonpotable. 95 % in commercial buildings.

City ordinance introduced: Now any building in SF can reuse blackwater, graywater, stormwater (hits ground), rainwater (hits roof), or groundwater.

Amended an ordinance: Buildings can now share non-potable water between them but only by contract, whether paid or free.

If you go into the sidewalk you need a “minor encroachment” permit and it street then “major encroachment” permit.

PUC’s nonpotable guidebook is available from John. Grants from PUC are available for certain sized buildings to encourage development of more such systems or similar. If you expect to offset enough per year you get the grant.Moscone and Transbay and others will use from groundwater systems on sumps. Sump water doesn’t need all the plant cycle stuff, just filter and UV.

The Bullet Center and two military systems in San Diego are using black water, otherwise most systems that exist now are sump (groundwater) or storm water.

John Todd is the inventor of the living machine and calls himself an ecological engineer.

AAA Clifornia Automobile Association building had a groundwater system but was a failure due to high iron in the water. (Different locations have different minerals in groundwater.) gave them orange toilet stains so they only operated it a month. Redid building and took the system out.

In PUC building graywater and blackwater both treated combined, so it all is called black water.

Gray water reuse for homes was allowed as of last year by state law changes. Became okay for using indoors in January 2014.

Airport has a hidden and fenced-in staff building that does the same full system for blackwater but only 475 people work there.

Solar panels produce 12 percent of the buildings energy and the wind turbines 1.5 percent so easily covers the system pumps and UV.

Living in the Plate Boundary and Through the Ice Ages
Guest Speaker: Tanya Atwater
7:30pm, Thursday, Oct 16th, 2014
FREE at the Randall Museum, 199 Museum Way, San Francisco, CA 

The geology and  landscapes of California are the results of a long history of plate tectonic interactions. The majestic granite walls of Yosemite, the rich agricultural soils of the Central Valley, and the wild-colored rocks of the Coast Ranges all reflect a long history of subduction. Our present beloved topography of dramatic mountains and sweet valleys reflect the evolution of the San Andreas plate boundary. In turn, all these features have been modified by sea level and climate changes during the ice ages. Using maps, landscape images and computer animations, Atwater will describe and explain all these geo-treasures.

You can read more about Atwater and her background here. In the 70s, she wrote about the origins and growth of the San Andreas fault, and contributed to our current understanding of a then nascent idea — it sometimes seems hard to believe that plate tectonics is a new idea! For a little teaser of what she has to show — see the video below…

Spreck Rosekrans came to us August 21st, 2014 to make the case for restoring Hetch Hetchy from reservoir to valley. The dam just passed its 100th anniversary in 2013, but what was hugely controversial at that time (more than 200 newspapers opposed, and John Muir famously broken-hearted by the decision) is now something of which most San Franciscans are proud.

Spreck spent only a little of his time on the “why” of making the effort. We lost this special place, and many people regretted the choice to dam it at the time, and today we have a chance to correct that mistake and restore an iconic place. To do that would show not just values, but also show that we can make meaningful water reform (not something that seems to come easily to Californians). The arguments (which Spreck also layed out) against it are many — people feel that the water is SF’s birthright, that Hetch Hetchy was a swamp, that we are actually protecting the valley, and there’s hydro power from the dam, the cost of removing it, and that we need more storage not less.

The main thrust of the talk was on the practical question of: if we removed the dam, how would we actually supply the water coming into the pipes of the 2.4 million people? It is not a pie-in-the-sky, wishy-washy notion as one might first think. EDF hired 2 mainstream engineering firms, and one law firm to look into what it would take (this resulted in a publication called Paradise Regained — the summary on this page gives a pretty good idea of what is proposed).

The amount of water involved is not the biggest. Of 5 big water projects over the last 22 years, Hetch Hetchy would involve less water than 4 (Delta ESA work, Central Valley wetlands, Trinity River, and rivers in the Central Valley). It would mean juggling water from various sources, doing what is known as “water banking”, taking more from the Cherry reservoir. Looking at the dry years, that kind of work (with the removal of the dam) would get is to around 80%.

The last 20% would take working to be more efficient with the water we have, from farming practices, to recycling, to just plain using less. These are things that of course are not easy, but they are things that we can do — and given current state of our reservoirs maybe things we will have to do anyway. At the end of the day though, we could have our cake and eat it too.

Hetch Hetchy left alone will be with us a long time – unlike other dams, silt does not seem to be a great problem there. Choosing to restore the valley to its former glory would no doubt have its complications and difficulties, but that choice is not just a fantasy.

SFPUC HQ as a wastewater treatment system
Guest Speaker: John Scarpulla
7:30pm, Thursday, Sep 18th, 2014
FREE at the Randall Museum, 199 Museum Way, San Francisco, CA 

The SFPUC built a new building very recently. John Scarpulla will tell us about how the new HQ building functions as a wastewater treatment system using an internal artificial swamp. The building is impressive in a lot of ways: consuming 32% less energy, 60% less water, and a 50% smaller carbon footprint than similarly-sized office buildings.

It is one of the first buildings in the nation with onsite treatment of gray and black water with an onsite “Living Machine” which reclaims and treats all of the building’s wastewater reducing per person water consumption from 12 gallons (normal office building) to 5 gallons.

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