Archive for the ‘oakland water’ Category

Water underground

4 January 2011

In today’s Chronicle, the Oakland writer Jon Carroll was musing about fire: “Usually it’s an obedient little creature, about the size of a cocker spaniel—until one day it turns into the largest, meanest cocker spaniel on Earth, and there goes the house.” Water, another of the four ancient elements, is the same way.

water main burst

Water is great in metered doses, delivered by tank and faucet. But “water dissolving, water removing” is no tamer than fire. Some time you should see firsthand what keeps it constrained: giant dams and stout mains, treatment plants, intricate feeder lines. The antique examples of dams and treatment facilities in Oakland are not the state of things today. Every now and then something breaks, like this line under Santa Clara Avenue in 2005, and a hint of chaos leaks out.

Last week a handyman had our water turned off for most of the day, with no word about when he would finish. As sunset approached we panicked enough to go out and buy 48 pounds of jugged water. But we didn’t need to use most of it. And so another bit of our earthquake preparedness is in place, a little lurch of progress. After the next big-enough one there will be water, water everywhere.

The ancients had a handle on things with their notion of four elements. Fire and water are worthy of the status, both full of motion and power. As for air, every weather report vouches for it. But it took someone more observant than most of us to see earth the same way and sum it all up as panta rhei, everything flows.

Drainage

18 December 2010

Oakland is a fine town unless it rains too much. Then we have to worry about all the water.

drainage

All things considered, Oakland’s landscape would prefer to be steep, forested hills raised by tectonics along the Hayward fault and gentle coastal plains that absorb the sediment washed off those hills. It’s a rich recipe that produces redwoods in the heights and forage and fruit in the vales. But with impervious roads and homes carpeting the upper slopes, we increase the runoff and undermine our own infrastructure. People like the homeowners above Broadway Terrace run flexible plastic lines over the edge of their properties to put the problem out of mind. But if you walk the road, you’ll find fresh gullies that will work their way uphill to the source of the problem regardless. Landslides will probably follow.

Big Rock

27 September 2010

I was at Temescal Regional Recreation Area yesterday—you probably call it Lake Temescal—and was happy to spot one of my favorite places.

big rock

This big hunk of Franciscan something-or-other sits near the head of the lake, displaying the ugly attractiveness that the French call jolie laide. Not a hundred feet away runs the Hayward fault, and there’s a free-running stream here too. Some classic oak trees shade picnic tables, and you can even swim where fish can nibble your toes.

Big Rock is the place I used to illustrate my post “Leave the Stone Alone.” Because for some reason, people seem to respect Big Rock.

San Leandro Creek (3)

25 July 2010

San Leandro Creek supplies almost all of the water in Lake Chabot. Here’s where it enters the reservoir, at its farthest eastern end.

lake chabot

San Leandro Creek is one of only three streams that cross the East Bay hills. The other two are San Lorenzo Creek, which cuts through Castro Valley and Hayward, and Alameda Creek, which traverses Niles and Fremont.

Since Anthony Chabot built the dam in the 1870s, the creek has dumped sediment and filled in about a mile of its course, creating new level land until today it’s slowly encroaching into the lake itself. Willow Park Golf Course is built on that land.

Not much sediment comes into the lake today, now that Upper San Leandro Reservoir has dammed the creek about four miles upstream. The round pads of aquatic vegetation flank the stream channel, which runs between low, muddy banks that were underwater when I visited last month. I think the vegetation traps sediment, which supports more vegetation, so that the patches tend to grow into a circular shape, reminiscent of bacterial colonies on a petri dish.

The first two ridges in this photo are underlain by the Joaquin Miller Formation, which extends along the whole south shore of the lake between here and the park headquarters. It’s mostly shale with a few large sandstone beds, tilted steeply upward. The farther ridges are all Oakland Conglomerate, and they stand maybe 50 meters higher. They look more sparsely vegetated, which may reflect the bedrock but might just as easily be due to historic land uses.

Drains to bay, an Earth Day message

22 April 2010

earth day

Some things are as obvious as gravity: Here’s the drain. There’s the bay. The geologist knows this so well that it never needs to be stated. The earliest thinkers of modern geology, as far back as Nicolas Steno in the 1600s at least, recognized that rocks arise from the everyday process of mud washing downstream to the sea. The signs are obvious in the petrified ripple and current marks, the fossilized sea creatures and the sandstones as clean as the stuff of beaches. “Drains to bay” might as well be written on the geologist’s coat of arms.

The rest of us need occasional reminders. Many of us never gave it a moment’s thought, probably those same Oaklanders who think that bears live in the woods up on Skyline. Earth Day is for them, the ignorant. Ignorant people are not bad people. Indeed, they’re only selectively ignorant, in that they don’t know something I consider important. Surely I’m just as ignorant in terms of what they care about. Anyway, “drains to bay” is a good start and it needs to be pointed out everywhere, even here where it’s obvious on Embarcadero East at the mouth of 14th Street Creek.

Earth Day, too, should always point out the basics. The rest of the year is for learning more and for putting knowledge into daily action—for Earth Life.

“Drains to bay” means that what we throw away doesn’t go away, any more than the ancient ripples and prehistoric creatures are totally lost.

Creek mouths

7 February 2010

Down at the Martin Luther King Shoreline Regional Park, three creeks debouch into San Leandro Bay. I already talked about San Leandro Creek; the other two are Lion Creek, below (more about it here and here), and Elmhurst Creek, bottom.

lion creek

elmhurst creek

Maybe with all our recent rain, they carried some sediment down to the bay, but probably not. Today both creeks are culverted to within an inch of their lives.

Old-fashioned water filtration

16 January 2010

On the path up to Chabot Dam, you pass this row of big tanks (click for big version).

water filtration

They were used to filter the water from Lake Chabot reservoir, and they’re still filled with fine sand plus, I suppose, the decades’ worth of slime and crap they kept out of Oaklanders’ stomachs and food.

This is roughly the same purification method we rely on when we use well water. The fine pores between mineral grains purify groundwater in two ways. First, of course, they physically trap the crap. Second, the minerals themselves chemically attach to many dissolved contaminants. Clay minerals are especially important for that.

The days are long gone when Oakland was served by wells. The water table has been pulled down all over the city by human intervention. The headwaters of Lion Creek were once called Laundry Canyon because there was so much good water coming down. Fruitvale irrigated orchards for many years. The rains we get here can’t keep up, so now we pipe our water in from the Sierra.

One important feature of the new state water compact, if they can ever get it nailed down, will be a new, wide-scale program of monitoring groundwater. We need that to get a handle on the whole resource. Everyone knows, except the statutes, that surface water and groundwater are intimately connected. Western water law is an ass.


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