Pull the county tax bill on a home near Serrano Avenue and Avenida de Santiago this year and you may notice a charge that wasn't there a couple of years back. It isn't a school bond or a Mello-Roos special tax for streets and sewers. It's an assessment tied to ground movement from more than three decades ago, and it behaves differently than almost anything else on that bill: it renews every year, adjusted for inflation, with no end date written into it.
That last part is the detail worth sitting with before writing an offer in this pocket of Anaheim Hills. For years, the assumption in this neighborhood was reasonable: homeowners had voted to fund landslide monitoring in two-year increments, which meant the charge could plausibly lapse if a future vote failed. That assumption held right up until it didn't. A vote in May 2025 to renew the assessment actually failed. Three months later, a revised version of the same ask passed by a wide margin, and it changed the funding structure from a temporary patch to something permanent. If you're evaluating a property inside this boundary, you're not looking at a cost that might go away. You're looking at one that was just locked in for good.
What the Santiago GHAD Actually Is
The Santiago Geologic Hazard Abatement District, known locally as the Santiago GHAD, is not a homeowners association and not a city department. It's an independent public agency formed in 1999 under a specific California law that lets a group of property owners fund the ongoing management of a geologic hazard. Anaheim's City Council created it by resolution after litigation over a 1993 landslide that followed an unusually wet winter. Heavy rain in December 1992 and January 1993 raised groundwater levels enough to reactivate an ancient landslide beneath homes on and near Avenida de Santiago, and several properties were eventually red-tagged.
The district covers roughly 305 parcels in the area around Serrano Avenue and Avenida de Santiago. Its job is to keep the landslide dormant by pumping groundwater out of the hillside. The system it maintains includes 37 wells and 87 drain lines that together remove about 15 million gallons of groundwater a year. It is a mechanical, ongoing operation, not a one-time repair, and mechanical operations need continuous funding.
For a long time, that funding came from a single source: a settlement paid by the city when the GHAD was formed, meant to generate enough investment income to run the pumps indefinitely. It didn't work out that way.
The Assessment That Almost Lapsed, and the One That Replaced It
By 2018, the settlement fund had shrunk from roughly $3.5 million to about $1.4 million, and low interest rates kept eroding it further. Property owners approved a two-year assessment to bridge the gap through mid-2025, but a two-year assessment has a built-in weakness: it has to be renewed, and renewal requires another vote.
That vote came due in 2025, and the first attempt didn't clear the bar.
| Vote date | Proposed budget | Weighted result | Outcome |
|---|---|---|---|
| May 2025 | $329,679 | 47.93% yes / 52.07% no | Failed |
| August 2025 | $349,679 | 73.67% yes / 26.33% no | Passed |
Under California's Proposition 218 rules, this kind of assessment vote is weighted by proportional benefit and risk rather than a simple one-owner-one-vote count, which is why the percentages above reflect ballots weighted by parcel rather than a flat headcount. What stands out is the direction of the swing. A smaller ask failed in May. A larger ask, for $20,000 more, passed comfortably three months later. The record doesn't spell out what changed in the conversation between those two votes. What changed in the outcome is unmistakable: property owners went from rejecting continued funding to approving it by nearly three to one.
The August vote also did something the earlier two-year assessments never did. It removed the expiration date. Once the district submitted the new assessment roll to Orange County in August 2025, the charge became a recurring line on affected property tax bills starting in December 2025, and it now continues annually with no built-in sunset. The amount is also indexed to the Los Angeles-Long Beach-Anaheim Consumer Price Index, recalculated each year using a June-to-June measurement period.
For a buyer, this is the mechanism that matters more than any single dollar figure. Two years ago, a skeptical buyer could reasonably tell themselves this was a temporary cost that residents might eventually vote down. That option is gone. The charge is now structurally permanent unless a future action changes it, and it grows with inflation by design.
What the Money Actually Funds Going Forward
The current assessment, drawn from an Engineer's Report dated June 12, 2025, isn't just paying to keep the existing wells running. The City of Anaheim contributes about $40,000 a year toward operations and separately funded a $175,000 study connected to a federal hazard mitigation grant application. According to the district's own materials, the GHAD applied for roughly $15 million toward a $20 million long-term structural fix, with construction completion targeted for late 2026 if the funding came through. As of this writing, that award has not been publicly confirmed, so the smart assumption for now is that the current dewatering system, not a new structural replacement, is what your assessment dollars are actually maintaining.
That distinction matters for underwriting a purchase. You are not paying into a project with a defined end point. You are paying into ongoing maintenance of aging infrastructure, with a possible future upgrade still pending federal approval.
What to Pull Before You Remove Contingencies
If you're in escrow on a home anywhere near this boundary, a few specific documents tell you more than a general disclosure conversation will:
- Confirm with the title company whether the parcel sits inside the Santiago GHAD boundary. Proximity to Avenida de Santiago doesn't automatically mean inclusion.
- Request the current Assessment Map and Schedule from the district. The dollar limit varies by parcel because the Prop 218 formula weights the charge by relative benefit and risk, so your neighbor's number isn't necessarily yours.
- Read the June 12, 2025 Engineer's Report specifically. Older reports describe an assessment structure that no longer applies.
- Ask how the current year's CPI adjustment has changed the number since December 2024, the base date used for future recalculations.
- Ask whether the FEMA hazard mitigation grant has been awarded. A funded structural project could eventually change both the scope of work and the long-term cost picture.
None of this shows up automatically on a standard natural hazard disclosure form, and because the GHAD is neither a city department nor a homeowners association, it's easy for a preliminary title report to list it without much explanation attached.
If You Already Own Inside the Boundary
If you're the one selling, the assessment is now a matter of public record on the county roll, which means it will surface in title work regardless of how it's framed in your disclosures. Getting ahead of the explanation, rather than waiting for a buyer's agent to ask, tends to keep escrow moving instead of stalling it.
FAQ
Is this the same as a Mello-Roos tax? No. Mello-Roos funds new infrastructure through bonds issued by a Community Facilities District under a 1982 law. The Santiago GHAD was formed under a separate state law to fund ongoing monitoring and remediation of an existing landslide, and it's funded through an assessment rather than a bond.
Does this affect all of Anaheim Hills? No. It applies only to parcels inside the GHAD boundary, roughly 305 properties concentrated around Serrano Avenue and Avenida de Santiago.
Could the assessment increase further or eventually end? The current structure adjusts annually for inflation and was designed to continue without an expiration date. Any change to the assessment limit itself would require another property-owner vote under the same Prop 218 process that governed the 2025 votes.
What if my home is close by but I'm not sure it's inside the district? Don't assume based on distance. Confirm boundary status directly with the title company or the GHAD manager, since the district lines don't follow neighborhood naming conventions.
Buying near a geologic hazard abatement district isn't a reason to avoid a neighborhood. It's a reason to read the right document before you write the offer. If you're looking at a property in this part of Anaheim Hills, Jose will pull the current Engineer's Report and the parcel-specific assessment limit before you remove contingencies, not after. Talk with Jose. Request a free consultation.
