Earthquake forecasts raise questions about the VA Clinic’s location

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A new warning about increased liquefaction risks at Alameda during the next major earthquake should catch the attention of leaders in the US Department of Veterans Affairs (VA). They plan to build a clinic and veteran’s benefits facility on an artificially constructed hill at the old airport in the middle of the earthquake liquefaction zone.

The Alameda Point map shows suggested veterans facilities. Image US Department of Veterans Affairs.

In an April 17 Mercury News article, USGS Earthquake Science Center Director Christine Goulet points out the city of Alameda as being at particular risk of severe damage from an earthquake along the Hayward Fault. The ominous headline was, “House of Cards: When the Big One Comes, Will Alameda Be Ready?”

A follow-up story published in Britain’s Daily Mail on April 22 states, “In addition to increased liquefaction risks at Alameda, (USGS) says there is also a 70 percent chance of one or more earthquakes of magnitude 6.7 or greater before 2030.” Bad for the residents of the island community, which is set almost entirely on reclaimed land.”

Earthquakes occur on the Hayward Fault approximately every 150 years. The last was in 1868 when Alameda was an oak forest and swamp. So, we missed the delivery date.

The earthquake risk for the proposed VA clinic comes from the fact that the ground is composed of sand and silt, the type of soil that is prone to liquefaction. The risks will be compounded by the fact that the VA will bring in 10,000 truckloads of soil to raise the site’s elevation to protect against sea level rise.

Adaptation of the Rising Tides Sea Level Explorer instrument, with a 52-inch entry for Alameda Point. The alternate VA clinic site near the USS Hornet remains dry. Still image from AdaptingToRisingTides.org.

Stacking more filling on top of the existing filling and then building something on top of it, as the VA suggested for her clinic, is exactly what the engineers warned against in the Navy base’s 1996 Community Reuse Plan. The section on seismic, geological and soil risk policies states that “strong to violent shaking of the ground is expected to cause earthquake-induced ground failure in parts of NAS (Naval Air Station) Alameda. The majority of the site is under hydraulically placed sand fill (pumped from a barge in bay) can be subject to liquefaction.” The term refers to loose, sandy soil that acts as a fluid due to intense vibration, which can lead to structural failure.

Hayward fault line. USGS photo.

The engineers go on to say that the use of filler over filler should be limited. The placement of the prosthetic filling should be limited to reduce the potential for overloading and associated stabilization of these areas of the NAS. It would be better to recondition (compact) the existing substratum material over the infill position.” But in the case of the proposed site for the VA clinic, simple compaction is not an option because the site must be raised with more soil to avoid the risk of sea level rise.

During the VA’s environmental assessment completed more than a decade ago, the engineers who wrote the geotechnical assessment only considered the potential for liquefaction from the San Andreas fault 12 miles from the site, not the Hayward fault six miles away. And according to Juliet, the Hayward crack is the real sleeper.

The VA does not plan to drive the steel trusses into solid ground to reduce the risk of earthquake damage. It’s too far. Instead, they propose building a VA clinic on a giant concrete slab with concrete piles that are supposed to remain intact and level during a major earthquake. Basically it will be a concrete slab over a sandwich of two layers of filler.

Why would the Department of Veterans Affairs pursue this difficult engineering exercise to withstand sea level rise and earthquakes when there are better alternatives at Alameda Point? It aligns with a national policy called “One VA”, which seeks to consolidate services into a single location wherever possible because it is more cost effective to have one plot of land rather than two or three. While the columbarium-style cemetery is for the area on runways, the VA may want to consider whether it would be wise to build its clinic on the same site.

The Google Earth map shows the currently proposed VA clinic site and the alternate site near the USS Hornet Museum. Overlays added by Richard Bangert.

There are much sought after locations for the clinic in Alameda Point that can be made available at the cost of new infrastructure. Two sites immediately come to mind.

One site is a site near the USS Hornet Museum where the city had previously offered 45 acres free of charge to the Berkeley Laboratory for its second campus in 2011. The Virginia clinic and parking lot would require only about 30 acres of that land. Long-term projections of sea level rise would render this area unsubmerged in the distant future, and so the questionable practice of stacking landfills to avoid flooding the structure could be avoided.

The Bachelor’s Registered Quarters complex of three buildings and a turf area currently used by the football teams. Richard Bangart’s photo.

Another ideal location would be the Bachelor’s Registered Quarters (BEQ) site, situated on a plot of approximately 30 acres. This complex could be demolished. Locating the VA clinic and benefits facility here would put it a short distance from the proposed Veterans Cemetery. It would eliminate all soil loads required to raise the proposed VA site because the BEQ site would one day be protected by a dam.

With knowledge of the latest earthquake predictions and options for minimizing risks, it’s never too late to visit the VA and the city to rebuild the clinic in another location. It will be less risky and probably less expensive for the VA. It will be easier for veterans to get there via public transportation. And it would be better for the city, with new infrastructure and a new facility for veterans seamlessly integrated into society, not stuck in old runways.

Contributing writer Richard Bangert posts stories and photos about environmental issues on his blog, Alameda Point Environmental Report, https://alamedapointenviro.com/. His writings have been collected at AlamedaPost.com/Richard-Bangert.

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