If you list properties in earthquake country, you may want to take a second look at those California Geological Survey (CGS) fault zone maps.
Thanks to budget crises now past, the CGS’s funding for earthquake fault zone mapping has all but disappeared in the last decade, leaving more than 300 fault areas left to map.
The 1972 Alquist-Priolo Earthquake Fault Zoning Act prohibits construction within 50 feet of an active fault and requires the CGS to map major earthquake faults across the entire state. [California Public Resources Code §§2622 et. seq.]
Areas within one-eighth of one mile from an active fault are considered to stand in an earthquake fault zone and require special disclosures for residential property sales. Areas within 50 feet of known faults require enhanced seismic investigations and stronger building methods for new construction. [California Code of Regulations §3603; see first tuesday Form 314]
Many of the unmapped faults cross heavily-populated urban areas. That’s where the City of Los Angeles recently found itself in hot water over issuing housing construction permits in known fault zones where the exact paths of the faults haven’t been identified by the CGS.
The issue was blown open when opponents of a proposed residential development in Hollywood discovered that project’s foundation is, according to the State Geologist, most likely square in the path of an active quake fault. In response, the developer forked over funds to conduct their own fault mapping effort. Now the state has ponied up, too, with Governor Brown promising to:
- increase the fault mapping staff fourfold; and
- dedicate permanent funding from construction permit revenue to the program.
Editor’s note — That fourfold staff increase takes the mapping team from one person to four—an illustration of how much the program has suffered under government austerity. The fault map program had up to six expert staffers until the budget crises of the early 2000s.
But even with a full complement of staff and funding, it will take time for maps to be completed for the unmapped areas. And with the passage of time and the creep of the earth’s crust, old maps — some dating to the early 1970s — begin to lose accuracy. For property owners in unmapped areas especially, this makes it difficult to know just what is on the line — literally and figuratively.
first tuesday insight
The takeaway for all agents: just because it’s mapped doesn’t mean it’s on solid ground.
The development snafu in Hollywood points to the problem with reliance on the CGS’s fault zone maps: they potentially are not accurate, or even complete, for a given area. But even if the exact location of a fault isn’t mapped, the presence of major faults is typically known, or at least concretely suspected.
Disclosures of earthquake fault zones and seismic hazard zones in the statutory Natural Hazard Disclosure (NHD) Statement, handed by a seller’s agent to prospective buyers up-front, are required regardless of the accuracy or condition of the state’s fault and hazard maps. The Alquist-Priolo law requires the disclosure of faults within one-eighth mile (660 feet) of a property; whether the exact location of the fault is 600 or 100 feet away makes no difference as far as the duty to disclose is concerned.
If data on fault locations is not available, the statutory NHD provides a response for “not yet mapped” – which, a buyer is to understand, does not mean there is no fault hazard present. [See first tuesday Form 314 and 315]
This becomes tricky when known or suspected faults come within throwing distance of a property. Within 50 feet of an active fault, Alquist-Priolo requires a licensed geotechnical engineer to file a report with the state on the property’s seismic conditions before permits for major alterations can be issued. Local building codes often require expensive seismic retrofitting as a condition to construction permit issuance, a critical material factor in a buyer’s valuation of a property. [Pub Res C §2623; CCR §3603(d)]
Thus, it’s a seller’s agent’s duty to make buyers aware of known faults in the area, even if the exact location is undetermined. And faults may still exist even though they are not known and mapped yet.
Let us suggest a rule of thumb: if you’re a seller’s agent and uncertain whether the property is near in a fault or hazard zone, and the state’s maps are inconclusive, protect your seller (and yourself) and disclose this fact to prospective buyers as early as possible, i.e., before entering into a purchase agreement.
These are the disclosure duties a seller’s agent owes a potential buyer. In turn, it is the buyer’s agent’s responsibility to guide their buyer through the interpretation and investigation of those disclosed facts. That advice includes reviewing the same state maps the seller’s agent first used to determine whether the disclosures were warranted.
A well-informed buyer and full transparency on the part of the seller and their agent prevents the problem of information asymmetry. Further, it ensures the transaction (and everyone’s fee) is on solid ground—regardless of what’s actually underfoot.
Re: “California’s funds for mapping earthquake faults running out” and “Gov. Brown calls for more funding to map earthquake faults”, from the Los Angeles Times