Urban Landslides/McKillop Road - Oakland

1935 ¹

McKillop Road has been the site of several landslides over the years leading to the destruction of part of the road and a number of houses. In some ways, it's been one long slide, sometimes moving faster, sometimes moving more slowly.

William D. Wood Park was subsequently created in the space instead of rebuilding. The road was originally constructed in the 1920s for the development of Mount Vernon Park, which opened in 1927. ²

1935-1936

The first reported* slide occurred in 1935, when 3174 and 3168 McKillop began sliding. By September, they were sliding an estimated 4" per day, and the houses were evacuated. Some residents blamed the nearby Central Reservoir, but no concrete evidence of that was found at the time. City engineers reported that similar sliding had occurred in the same area in 1909. ³ The city authorized $500 to pay for a special study of the slide. ⁴ By January 1936, two houses had been moved, and the Chambers house had slid 25'. ⁵

1935 ³1935 ¹⁴1935 ¹1935 ¹1950 Sanborn excerpt. 3168 and 3174 are to the right.

1942

Heavy rains in February 1942 led to 8 homes sliding. At least one resident moved out all his furniture, and stripped the home of its hardware. ⁶

1950s

The land continued sliding. A 1952 article about a slide noted that some houses had flexible gas lines installed to prevent them breaking as the houses shifted. One homeowner was a builder, and installed adjustable jacks under his house to account for the sliding. ⁷ A geologist and specialist in earth movement prepared a report which said no corrections would be effective "unless seepage from the reservoir is corrected." City engineer Earl Buckingham said "while I personally am not convinced that the reservoir was the original cause of the slide, I do believe it is a factor in the present phase of the slide movement." ⁸

There were delays and more finger-pointing, but the city agreed to share in the estimated $5,000 costs to address the problem by grading the area. The city council agreed to go ahead if 30 families in the area agreed to sign waivers releasing the city from liability. ⁹

1958 brought more storms, more worries, and additional sliding. And more disagreements about the cause. ¹⁰

1950 Sanborn excerpt. Note the former house locations.

Possible Causes

Central Reservoir? Sausal Creek? Heavy rains? Underground wells? ¹⁴ Like many things, the causes are complicated; ^11.12 it would be interesting to read geologist Charles H. Lee's writeup on the slide from 1944 for a hands-on, professional view. But some things are known; waterways erode the ground they flow through. Sausal Creek flows at the bottom of the slide area, and like other creeks in Oakland, the flow is highly seasonal. The highest flow comes at the end of heavy rains when the ground is the most saturated and most prone to sliding.

In my non-professional opinion, it's probably a combination of factors: cutting the road for development, building (including excavating for foundations) on filled material, and heavy rains all contributed to the initial* slide in 1935. Once the earth was moving, seepage from the reservoir, if any, would exacerbate the problem. Some of the attempts to fix the problem, like lining the creek with concrete, probably made the problem worse.

(* City engineers reported that sliding had occurred in the area in 1909, ^3,14 before the Central Reservoir was built. It wasn't until roads and houses were built in the area that anybody else took notice.)

1970s to Present Day

Sliding has continued in the area. In 1971, EBMUD took the step of putting water lines on the surface as a precautionary measure. ¹³ At some point the Army Corps of Engineers apparently drove pilings into the ground to try to stabilize the area. In 1976, the city created William D. Wood Park, officially giving up on any attempts to re-claim the area for housing.

Sliding resumed during 2006 at the south end of McKillop Road, destroying two more homes along with the parking lot of the church there.