The Pill Hill/Fairmount ridge walk (#20)

This hills-and-paths walk is number 20, “Broadway and Oak Glen Park,” in Charles Fleming’s Secret Stairs East Bay. This is not a bedrock walk, like the previous ones I’ve featured, but a landform walk. Let’s start this time with the topography.

This walk starts in the bayside flats, crosses two hills and two streams, and returns from the side of a third hill. The first hill is Pill Hill, and the second (Fairmount ridge is my name for it) and third are lobes of the Adams Point upland. These are parts of a larger structure that is central to Oakland’s character, an ancient Pleistocene alluvial fan. Here it is, marked “Qpaf” on the geologic map.

This walk takes in the leftmost edge of the fan, crossing two valleys of the Glen Echo Creek system which dissect the fan. The creek feeds the narrow west arm of Lake Merritt.

All right, here’s the route with the locations of the following photos.

Here’s the view up Hawthorne Avenue to the edge of Pill Hill. The land west of the fan is a modern alluvial flat with almost no topography to it beyond subtle levees along the modern Temescal Creek and the notorious filled-in marsh that once underlay the ill-fated Cypress Structure in West Oakland. The Pleistocene fan has fairly abrupt edges like this all around it.

As you go over Pill Hill and Summit Road on its spine, take a close look at the topography ahead of you. The near ridge is Fairmount ridge, made of Pleistocene alluvium, and the distant hills are Cretaceous and Tertiary sedimentary rocks. The eminence at the foot of the high hills is the older Franciscan block that underlies Piedmont and upper Rockridge.

The walk goes down into the valley of Glen Echo Creek. Brook Street is named for the Broadway branch of the creek, which is culverted under Mosswood Park and runs open to the sky in the backyards here. This shot is at the foot of 30th Street.

If you go upstream a little ways you can spot the culvert where the two branches join.

Next we climb the other side of the valley up a long flight of stairs, then turn right and follow the ridge top, along Fairmount Avenue, for a ways. A detour of stairways leads to Hamilton Place, at the toe of the ridge (the new Whole Foods place cut into that toe; unfortunately I never got a good look at the cut). From here we look across the next valley, which I might as well call Harrison valley.

This valley has a well-developed profile, but apparently it never had a permanent creek. The Oakland watershed map shows only a culvert here. Anyway, we walk up the far side of this valley and return west on classic Perkins Way, where we can look back at the other two ridges.

Back up on Fairmount ridge, we stroll up quiet Kempton Avenue, where this nice driveway wall of California mariposite lives.

Soon enough we find ourselves again at the steep edge of Glen Echo Creek valley. If you limit yourself to walking, Oakland is really quite a rugged place.

At the bottom is a precious remnant of early Oakland’s streambeds, Glen Oak Park. An old concrete bridge crosses the stream, and if you have time to stroll up and downstream there are some fine buildings here too.

I would be remiss not to mention that a little farther, at the foot of Piedmont Avenue, is a good sushi place, Drunken Fish.

Radio Beach

Radio Beach is Oakland’s nearest thing to a natural beach. It’s city land, on the north side of the Bay Bridge approach past the toll plaza. There is no lonelier or prettier spot on Oakland’s waterfront. This is the view toward the bridge as you enter the beach.

This was near low tide yesterday, and the mudflats stretching all the way to Emeryville were tempting. Here’s the view back from the other end, with some of the radio towers.

And here’s the view out, with Mount Tamalpais, Angel Island and the Tiburon Peninsula on the skyline. Click the image for a 1000 pixel version.

The sand is very fine grained, given the energy of the waves and the available sediment in the Bay. It collects here where a little extra wave energy gets focused, against the buttress of the bridge approach. Not a super beach, but a real one.

Oakland groundwater

I’ve been taking National Ground Water Awareness Week to think a little more than usual about groundwater. My KQED Quest blog post yesterday, on Bay area groundwater, mainly focused on the South Bay. Oakland’s not a big groundwater town.

The rancheros and early Anglo settlers here all dug wells, of course. As I understand it, Dunsmuir House still has an operating well, the Pardee Home has a water tower that suggests the presence of a well, and some of the other old properties must have them too. Some long-standing Oakland industries probably have wells, and maybe the golf courses too. I don’t know a lot about it.

But municipal water service from Oakland’s earliest days exploited local surface water, starting with Temescal Creek and ending with San Leandro Creek (see the two dams post). Lion Creek supplied laundries in the area near Mills College once called Laundry Canyon. Today we’re all served by East Bay MUD with clean Sierra runoff from the Mokelumne River watershed. In Oakland, surface water rules.

Today groundwater is off the radar here. Sure, we have to clean it up where old gas-station tanks used to leak—this monitoring well is from one of those. It seems to me that the aquifer west of Chabot Dam, in the alluvial fan crossed by San Leandro Creek in far East Oakland, must have good potential, and so would Fruitvale and Temescal. San Francisco is opening up its formerly used aquifers to serve emergency purposes; we ought to look into that too. Why go to such expense to clean up the groundwater and not get some sustainable use out of it at the same time?

Bird islands

Lake Merritt is formally a wildlife sanctuary, declared in 1870, but the land itself is artificial and needs maintenance.

The Parks and Recreation Department website says that the first bird island was built in 1925 and the other four were added in 1956. As long as I can recall (since 1989) they have been a tangle of thick foliage and tall snags, but right now the islands are undergoing a makeover. Anyone have more information?

Water underground

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 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

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

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

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

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.