Does Your Almaden Valley Home Have a Well or Septic System?

If you're buying or selling a home in Almaden Valley, San Jose, don't assume it's hooked up to city water and sewer the way most San Jose properties are. A meaningful share of homes on Almaden's hillside and foothill lots run on a private well, a septic system, or both, and Santa Clara County regulates those very differently than a standard municipal connection. Before you write an offer or list your home, find out which systems your specific address has. The permitting, inspection, and disclosure details below come from Santa Clara County's Department of Environmental Health and are current as of October 2026.

Why Do Some Almaden Valley Homes Have a Well or Septic System?

Most of Almaden Valley is on San Jose's municipal water and sewer system, just like the rest of the city. The exceptions tend to be the larger hillside and foothill lots, where some homes were built before service lines reached that far, or where a sewer main simply isn't close enough to make a connection practical. It's not a neighborhood-wide feature. It's an address-by-address fact, and you shouldn't assume either way just because a nearby home has city service or doesn't.

How Do You Find Out If Your Address Has a Well or Septic System?

A few reliable ways to check before you're deep into escrow:

• Ask the listing agent directly, and ask for documentation, not just a verbal answer.
• Review the preliminary title report for recorded well or septic easements.
• Call Santa Clara County's Department of Environmental Health Land Use Program at 408-918-3400. For wells specifically, the county keeps construction records back to 1989, Santa Clara Valley Water District (Valley Water) has records back to the early 1970s, and the state keeps some records back to the early 1900s.
• Once you're in contract, check the seller's Transfer Disclosure Statement, which asks sellers to state whether the property has a well or a septic system.

Older wells sometimes have no driller's log on file at all. If that happens, the county can still tell you what permits, if any, exist for that address.

What Does Santa Clara County Require to Install or Replace a Well?

You can't just hire a driller and start. The county's Department of Environmental Health reviews and clears the site first, checking setbacks and feasibility, and then Valley Water issues the actual well construction permit. Only a licensed C-57 well drilling contractor can do the work. Setbacks matter here: a new well generally needs to sit at least 50 feet from sewer mains or laterals, 100 feet from septic tanks, leach fields, or chemical storage, and 150 feet from a cesspool or seepage pit. On a tight hillside lot, those distances can rule out certain locations before you even get a quote.

Does Santa Clara County Require a Septic Inspection Before You Sell?

No. Unlike some neighboring counties, Santa Clara County does not require a mandatory point-of-sale inspection for an onsite wastewater treatment system, or OWTS, which is the county's formal term for a septic system. That said, the county's own OWTS guidance recommends pumping and evaluating the system before a sale and including those results in your disclosure, and you're still legally required to disclose whether the property has a septic system and whether you know of any defects in it, which happens on the state's standard Transfer Disclosure Statement. Skipping the inspection doesn't get you out of disclosing what you already know.

What Triggers a Required Septic Upgrade During a Remodel?

This matters if you're buying with an addition in mind, or selling a home that's already been expanded. Under the county's onsite wastewater ordinance, a major expansion, meaning more than 500 cumulative square feet of building area added since March 2, 1982, or a major intensification of use such as added bedrooms, generally requires the septic system to meet current code. A smaller addition still triggers an on-site inspection and tank pumping, unless the tank was already pumped within the last three years. If you're eyeing an ADU or a second story for an Almaden hillside home, confirm where the existing system stands before you plan the addition, not after.

How Often Should a Septic Tank Be Pumped?

The county's SepticSmart guidance recommends pumping generally every 3 to 5 years, depending on household size and system use. Whenever a tank is pumped, the pumping company is required to inspect the tank and dispersal field and file a report with the county within 30 days. As a buyer, that report is one of the most useful documents you can ask for, since it tells you when the tank was last serviced and whether anything looked off at the time. You can also ask the county for a limited inspection report on file for the address, which checks for obvious deficiencies without a full evaluation.

What Should Sellers Verify Before Listing an Almaden Valley Home?

Even though the county doesn't require it, I tell sellers with a well or septic system to get it evaluated before the home goes live, not after an offer comes in. A dated pumping or service report in hand makes your disclosure cleaner and gives buyers something concrete instead of a vague assurance. If an evaluation turns up a real problem, you have a choice most buyers will expect you to make: fix it before listing, or price and negotiate around it with full disclosure. What you shouldn't do is write "well and septic in good working order" on a disclosure with nothing to back it up. For the full picture of what California requires sellers to disclose, see my San Jose real estate contracts and disclosures guide.

What Should Buyers Verify Before Removing Contingencies?

A few things worth confirming before your inspection period closes:

• Get written confirmation of which systems the home actually has. Don't rely on what a neighboring property uses.
• Ask for the most recent septic pumping or service report, and find out how old the system is if the seller knows.
• Order a bacteriological water quality test on a well before you remove contingencies. Domestic well owners may qualify for free basic testing through Valley Water's groundwater quality program.
• If you're planning to add square footage or bedrooms, ask whether the current septic system already meets code, since that affects your remodel budget.
• Loop your lender in early. Many loan programs want some confirmation that a private well or septic system is functioning before they'll finalize the appraisal, and starting that conversation during your inspection period beats finding out about it a week before closing.

I've also written about verifying Fire Hazard Severity Zone status for Almaden hillside addresses, which is worth checking alongside a well or septic review on the same property, and about the broader list of things to verify when buying or selling in Almaden Valley. If you're looking at an older home specifically, pair this with my inspection and upgrade risk checklist, and if you want the basics on what a standard inspection covers first, start with my guide to home inspections in San Jose.

The records I've reviewed document 51 closed Almaden Valley, San Jose transactions with buyer-side, seller-side, or both-side client representation, based on public MLS-derived records reviewed through September 15, 2026. Real Estate 38 is also recognized as the #1 real estate group in San Jose by sold units, based on MLS and RealTrends data from 2018 to 2026, with top 1% nationwide recognition based on sales volume and units sold from 2014 to 2026.

Frequently Asked Questions

Do all Almaden Valley homes have a well or septic system?

No. Most Almaden Valley properties are connected to San Jose's municipal water and sewer system, the same as the rest of the city. Private wells and septic systems show up mainly on certain hillside and foothill lots, and the only way to know for a specific address is to check directly rather than assume based on a neighboring property.

Is a septic inspection legally required to sell a home in Santa Clara County?

No. Santa Clara County does not run a mandatory point-of-sale septic inspection program the way some nearby counties do. You're still required to disclose whether the home has a septic system and any known defects, and the county recommends an evaluation before listing even though it isn't mandatory.

How often should a septic tank be pumped?

Santa Clara County's SepticSmart guidance recommends pumping generally every 3 to 5 years, depending on household size and how heavily the system is used. Whenever a tank is pumped, the pumping company must inspect the tank and dispersal field and file a report with the county within 30 days, which becomes a useful record for a future sale.

Can I just drill a new well if my current one fails?

Not on your own. Santa Clara County's Department of Environmental Health has to clear the site first, Valley Water then issues the actual construction permit, and only a licensed C-57 well drilling contractor can do the work. Setback requirements from septic systems, sewer lines, and chemical storage can also limit where a new well is allowed on the lot.

Will adding a bedroom affect my septic system?

It can. Santa Clara County's ordinance treats added bedrooms or a meaningful increase in occupancy as a major intensification of use, which generally requires the septic system to meet current code. Even a smaller addition can trigger a required inspection and pumping if the tank hasn't been serviced in the last three years.

How do I find out if my address already has a well or septic permit on file?

Start with Santa Clara County's Department of Environmental Health Land Use Program at 408-918-3400. For wells, the county's own construction records go back to 1989, Valley Water's go back to the early 1970s, and the state's go back further still. A preliminary title report and the seller's disclosure statement are the other two places this usually shows up.

Zaid Hanna
408-515-1613
www.re38.com