Liquefaction in Mountain View: Why It is Important to Understand Earthquake Risk While Buying a Home in South Bay
Deniz Kahramaner is the Founder & CEO of the data-driven Real Estate Brokerage Atlasa. His mission is to help home buyers understand the tradeoffs of different home options using big data and analytics. Feel free to reach out to Deniz if you need help with home purchases and listings in liquefaction at deniz@atlasa.com
What is Liquefaction?
Liquefaction relates to the status/composition of the soil and ground on which various counties, cities, and neighborhoods reside. Generally, liquefaction is a natural hazard that is triggered by the occurrence of larger earthquakes. The levels of liquefaction range in intensity. In a particular area, liquefaction levels can be very low, low, moderate, high, or very high. As liquefaction levels rise on the scale, the ground/soil becomes increasingly susceptible to falling or sinking in the face of a high-intensity earthquake.
Why does Liquefaction exist?
At the end of the industrial boom, the Bay Area coastline was populated by many bay, marsh, and creek areas that made structural development near-impossible. In the mid-1800s, the United State Federal Government adopted the Arkansas Swamp Lands Act of 1850. The Swamp Lands Act legalized the State of Arkansas and other states reclaiming swamp and overflow lands. This reclamation would include claiming a title of the lands.
According to the California State Lands Commission, beginning in 1855, “California received over two million acres of swamp and overflowed lands, which was loosely defined as lands that required drainage or levees in order to be cultivated.” Following the receipt of these lands, the State of California used foreign fill to expand the Bay Area coastline for building and development, and to fill marsh and creek areas around the Bay. This artificial/foreign fill was created using rock, rubble, soil, or even mud pumped from the bottom of the Bay and left to dry. Due to their man-made nature, these lands are highly susceptible to shifting and sinking.
How much is Mountain View affected by Liquefaction?
The level of liquefaction in a particular area varies from region to region.
In most of Mountain View, it can be seen from this scale that the liquefaction levels are Moderate. However, a small pocket in the southeast corner of the city is on a low level of liquefaction.
To determine whether liquefaction affects pricing, we took a data-driven approach by observing single-family home sales from the start of 2020.
Out of the 784 homes, we found the following:
- Over 90% or 729 homes are in moderate liquefaction.
- Only 7% or 54 homes are not affected by liquefaction.
- 0.1% or 1 home is affected by heavy liquefaction. We did not analyze pricing because there are not enough data points to make a conclusion.
How does Liquefaction Affect Home Prices in Mountain View?
There is a price premium to live in the few homes that have low susceptibility to liquefaction as shown in the price charts below.
When we further dissect the data, we found that homes in low liquefaction had a price advantage across 3–5 bedroom homes. Most families looking in Mountain View are eyeing these homes.
We understand that liquefaction can be conflated with other factors that affect pricing. In addition to better soil, the low liquefaction areas in Mountain View are home to some of the nation's top schools.
In general, homes that sit in very high liquefaction areas require a necessary amount of caution and consideration, as the danger of being in a liquefaction zone in an earthquake-frequent state such as California is not one to be overlooked.
To Prospective Buyers
The final decision for whether a home is the right one for you will always come down to you. If liquefaction matters a great deal to you as a buyer, then Atlasa will diligently find properties to fit your desire. On the flip side, if you want a home and are not bothered by its presence in a liquefaction zone, Atlasa will aid you in the purchasing process in equal capacity. What matters most is that as a buyer you are thoroughly informed so as to make the best possible decision. If you are looking to buy a home, please feel free to contact us at deniz@atlasa.com.
To Prospective Sellers
More than anything, it is important to remember that you have many options and opportunities to sell your home, even if it is in a moderate to very high liquefaction zone. If you would like to explore your options, please reach out to Atlasa Real Estate at deniz@atlasa.com so we can get the conversation started.
