San Francisco Regrade-Rincon Hill

San Francisco has long been famed for its hills. There are 43 of them, or 42, or 53, or perhaps even 49, including such well known ones as Telegraph, Nob, and Russian. As happened and still happens in many urban centers, the hills became the fashionable place to live, offering good views and clean air, high above the miasmas that lingered in the lowlands. One of the earliest of these desirable knolls was Rincon Hill, which first attracted the wealthy in the 1850s and by 1861 was described in the Daily Alta California (Feb 2) as “the most elegant part of the city.” But its enviable reputation did not last long.

As James Sederberg pointed out in his fine essay in foundSF, steep hills did not always engender themselves with San Franciscans. One of those hillophobes was John Middleton, a very influential and well-connected resident. Middleton apparently was frustrated that north-south traffic tended to avoid going over the steep edifice of Rincon by taking the low sloped Third Street, thus bypassing property he owned at the base of the hill on Second Street. One way around this problem would be to have the City cut a swath through Rincon along Second Street.

[nggallery id=36]In order to aid the city in their decision-making, Middleton ran for the state assembly in 1867, won, with a little help from his friends, and soon introduced Assembly Bill 444. It authorized a modification of the grade of Second Street for the three blocks between Bryant and Howard Streets. The deepest cut of the canyon would be in the middle, 87 feet at Harrison Street. A bridge at Harrison would connect the two sides of new canyon, with additional steps leading out of the gap.

Not everyone approved of the vivisection of Rincon, including the Alta, which reported this “astounding piece of vandalism was perpetrated …[with] no attention paid even to the most elementary rights of property.” In contrast, an editorial in Chas D. Carter’s Real Estate Circular, which was commenting on a California Supreme Court Case ruling that the San Francisco Board of Supervisors had to allow the cut, noted that the cut would lead to the filling of swamps, as well as having a “beneficial effect upon the extension of Montgomery Street.” (February 1869, v3 n4)

The cut took a year and required 500 men and 250 teams of horses. I have not been able to track down how much dirt was moved though one article in the Real Estate Circular (July 1869, v3, n9, p1) mentioned “120,000 square yards,” which I assume should be cubic yards, as that is how engineers measured these projects. Costing nearly three times more than budgeted, the total cost was about $380,000 with the Harrison Street bridge totalling $90,000.

Despite Middleton’s hopes the cut did not serve its purpose and became an unsavory place frequented by hudlums, leading one writer to note that the only way to pass through the cut was with gun in hand. It was also dangerous as the steeply cut hillsides slid during rainstorms.

One curious aspect of the Second Street Cut, which makes it far different from regrading in Seattle, is that only the street was cut. Properties on either side of the street were not lowered at the same time. Instead, the homes were perched high over the canyon below, which might be nice in a natural setting but was certainly not good in a city. This situation led to the Real Estate Circular calling for the removal of the entire hill: “the space it occupies is required for commerce, and its removal will transform the land from private residence into business property.” (July 1869, v3, n9)

In the end, Rincon Hill became what Robert Louis Stevenson described as a “new slum, a place of precarious, sandy cliffs…solitary, ancient houses, and the butt-ends of streets.” No more hill removal was attempted after this debacle, in part because of the start of the city’s first cable car service in late 1873.

— The most detailed account of the Second Street Cut and its problems is Albert Shumate’s Rincon Hill and South Park: San Francisco’s Early Fashionable Neighborhood, which provided many details for this post.

I would also like to thank LisaRuth Elliott and Chris Carlsson of foundsf.org for their help.

Material for for this story comes out of research I have done for my new book on Seattle – Too High and Too Steep: Reshaping Seattle’s Topography.

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Seattle Map 5: Denny Hill Underwater

Recently I was standing atop Pier 66 along the Seattle waterfront considering another central tenet of the city’s urban mythology, which is that Denny Hill no longer exists. Conventional wisdom holds that our forefathers eliminated the high mound north of downtown to make way for the coming tide of business. This is not entirely true. Denny Hill still stands; you just need to know where to look. Ask UW oceanographer Mark Holmes and he can show you.

In the summer of 1988, Holmes and two colleagues decided to examine the seafloor of Elliott Bay. The trio wanted to better understand sedimentary processes and their relationship to human made changes in the bay. The earliest map they consulted, an 1875 hydrographic chart, showed that close to shore the seafloor dipped gently and uniformly. When they looked at a map from 1935, they found that the moderate slope was gone, replaced by a shoal, or linear landform “unlike any natural feature” typically found in Puget Sound, says Holmes. The center of the mound was about 500 feet offshore between the Bell Street Pier and the Edgewater Hotel. (Loeffler, Robert D., Mark L. Holmes, Richard E. Sylwester, “In Search of the Denny Regrade: Fate of a Large Spoil Bank in Elliott Bay,” Puget Sound, Oceans ’89 Proceedings, 1989, pg. 84 – 89.)

Denny Hill Underwater – USGS Seafloor Mapping

Hoping to better understand the anomalous landform, Holmes’ team sailed into Elliott Bay on the research vessel Coriolis to run what is known as a seismic reflection survey. Widely used by geophysicists and oceanographers, the technique utilizes sound waves to take a snapshot of layers of underwater, or underground, rock. When the energy pulses bounced back, an array of detectors recorded the data and generated an image of the shoal’s surface and subsurface.

The seismic reflection data revealed a hummocky top, punctuated by an odd, flat-bottomed summit depression. Internally, the shoal consisted mainly of coarse sand and gravel with flanks of clay and silt that sloped steeply to the west. It ranged between 10 to 120 feet thick, measured 1,500 feet wide by 2,500 feet long, and contained an estimated 8.9 million cubic yards of sediment.

Denny Hill Underwater – UW Center for Environmental Visualization

The mound’s shape and texture made Holmes suspect that it was the product of dumping, which the Army Corps of Engineers does regularly into Elliott Bay with sediment from the Duwamish River. Such spoils, however, normally go into deeper sites, where contaminants would have less impact on marine wildlife. As Holmes and his team began to further research the history of Elliott Bay, they realized that they had discovered something more unusual. They had “stumbled into the Denny Regrade” story, says Holmes.

How Denny Hill ended up in Elliott Bay

They learned that most of Denny Hill, the high mound that had stood at the north end of downtown and which was leveled between 1898 and 1931, ended up in Elliott Bay, carried out by a sluice during the initial periods of regrading and later by self-tipping barges. Conspicuously, the total sediment removed from the hill corresponded to within ten percent of the shoal’s volume. Holmes’ team accounted for the difference by landslides on the steep faces, which carried material deeper into the bay. And the odd summit flat spot? Apparently a boat had run into the mound, and dredgers had had to go out into the bay and flatten the boat-damaging, high point.

In Holmes’ mind, they had clearly found the long forgotten remains of Denny Hill. After more than a half century, the famous mound had been rediscovered. It had not been eliminated, it had just been displaced.

I know it’s a bit of a stretch to write that Denny Hill still stands but the submarine mound in Elliott Bay is the lone topographic remnant of the famous knoll that formerly stood at the north end of downtown Seattle. By rediscovering the regraded hill, Holmes and his fellow researchers have provided a direct link to Seattle’s greatest attempt to better the city through reshaping its topography.

Material for for this story comes out of research I have done for my new book on Seattle – Too High and Too Steep: Reshaping Seattle’s Topography.