What is the Aliso Canyon disclosure and does it apply to my Porter Ranch home?

The Aliso Canyon disclosure refers to the SoCalGas natural gas storage facility where a methane leak occurred from October 2015 through February 2016 - the largest methane release in U.S. history at the time. California sellers in the affected Porter Ranch and adjacent areas are commonly expected to disclose this material fact in residential transactions. The class-action settlement was approved in 2021; payouts have been distributed. The facility continues to operate under tighter regulatory limits as of 2026.

Aliso Canyon Disclosure: Does It Apply to My Home?

If you're buying or selling in Porter Ranch or nearby parts of the northwest San Fernando Valley, you'll see the Aliso Canyon disclosure in the package. It refers to the SoCalGas Aliso Canyon natural gas storage facility leak that started in October 2015 and was sealed in February 2016 - the largest methane release in U.S. history at the time. I'm Brian Cooper, REALTOR(R) at eXp Realty. Below is what the disclosure is, where it applies, and what the 2026 settlement status looks like.

Direct AnswerThe Aliso Canyon disclosure tells buyers a home is near the SoCalGas Aliso Canyon facility where a 2015-2016 methane leak occurred. California sellers in the affected area must disclose material facts about it. The class-action settlement was approved in 2021; payouts have been distributed. The facility is still operating.

Data current as of May 2026.

Direct Answer

The Aliso Canyon disclosure is not a single statutory form like the TDS. It is a material-fact disclosure added to many Porter Ranch and adjacent transactions by listing agents and sellers because the leak and its aftermath are widely considered a material fact under California disclosure law.

If your home is in the impact area or near the facility, you should expect to see disclosure language about it in the sale package. Buyers should read it, ask questions, and decide whether further investigation is warranted.

Why this question matters

Porter Ranch home values dropped meaningfully in the months after the leak in 2016. They recovered over subsequent years as the facility remained operational under tighter oversight. Buyers ask, reasonably, whether the disclosure changes their risk picture today.

Failing to disclose a known material fact in a California real estate transaction can expose a seller and listing agent to post-closing liability. That's why you'll see this language even on transactions years after the event.

The detail behind the answer

Quick timeline of what the disclosure references and where things stand as of 2026.

Date / item	Status
Oct 2015	Leak begins at SS-25 well
Feb 2016	Leak sealed
2017	Operations resume under tighter limits
Sep 2021	Class-action settlement approved (~$1.8B)
2022-2024	Settlement payouts distributed
2026	Facility operating; future closure proposed but ongoing

How to verify

Three things to do as a buyer. First, read the Aliso Canyon language inside the disclosure package carefully and ask the listing agent any questions before contingency removal. Second, check the California Public Utilities Commission and SoCalGas pages for the current operational status of the facility. Third, do your own diligence on the proximity of the specific address to the facility footprint.

As a seller, work with a listing agent who builds the disclosure correctly. Failure to disclose a material fact known to the seller is one of the most common sources of post-closing litigation in California residential transactions.

Step 1: Read the Aliso Canyon disclosure language carefully.
Step 2: Check current CPUC and SoCalGas status on the facility.
Step 3: Confirm what your seller actually knows; ask for backup.

What I tell clients

I don't tell buyers to walk from Porter Ranch over the Aliso Canyon history. Plenty of buyers have purchased and lived there happily since 2016, and the market has absorbed the event. But I do tell them to read the disclosure, ask questions, and decide based on full information rather than skip it.

For sellers in the affected area, I treat the disclosure as standard. Including it cleanly tends to build trust with buyers and reduces post-closing risk. Skipping it because 'everyone knows' is not a defense in court.