A Southlake seller sat down this July to sign the paperwork on a listing in one of the city's older custom-lot enclaves and found a form that wasn't there in June. It asked about groundwater conservation districts, well registration, and whether the property's water rights had ever been leased or sold. The seller's first reaction was that someone at the title company had grabbed the wrong packet, the one meant for a ranch listing out past Decatur.
They hadn't. The form is new, it's mandatory, and it applies to a Southlake estate the same way it applies to five hundred acres in Wise County. The assumption that well-and-septic paperwork is a rural problem, something that happens to other people's land, is exactly the assumption that catches sellers off guard in the parts of Southlake built before the city's water and sewer lines reached every lot.
The Form Nobody Expected to See in a Suburban Closing
On May 4, 2026, the Texas Real Estate Commission adopted a new standalone disclosure, Water Notice: Seller's Disclosure About Groundwater and Surface Water Rights, alongside a related update to the standard Seller's Disclosure Notice. The water notice became mandatory on July 1, 2026. If you're under contract on a Southlake home today, this is not a future concern. It is already the paperwork you're signing.
The water notice asks sellers to state what they know about wells on the property, whether it sits inside a groundwater conservation district, whether there's a pond, lake, or water tank, and whether any water rights have been sold or leased separately from the land. The companion update to the main disclosure form adds a handful of items that read like a checklist for a country property: permanently installed generators, private roads, above-ground storage tanks over 500 gallons, and conservation easements.
None of that sounds like Southlake. Most of Southlake's inventory sits on municipal water and sewer, in subdivisions built specifically to avoid this conversation. But the form doesn't ask what's typical. It asks what's true of the specific lot you're selling, and a meaningful slice of Southlake's larger, older custom parcels were never fully absorbed into that municipal picture.
What Southlake's Own Building Rules Already Assume
The city's Residential New House Guidelines, updated in February 2026, don't treat wells and septic systems as a hypothetical. They treat them as a standing category of property the building department processes routinely. Any lot on septic needs a trip ticket uploaded before inspection can proceed. Any house drawing water from an alternative source, meaning a private well rather than the municipal system, gets classified by the water department as a high health hazard, which triggers a required physical separation between that well and the city's water supply to prevent cross-contamination.
That language exists because the city has enough of these properties to need a standing procedure for them, not because someone imagined an edge case. A building department doesn't write cross-connection rules for a problem it expects to see once a decade.
Where This Actually Shows Up on the Ground
The properties most likely to carry a well, a septic system, or both are not Southlake's newest construction. They're the large-lot, custom-built enclaves that predate or sit alongside the city's densest development, the kind of one-acre-plus cul-de-sac developments built by local custom builders on land that was agricultural or semi-rural within recent memory. Small, single-street developments like these, often just ten or eleven homesites carved out of a former pasture or wooded tract, are exactly where a legacy well or a septic tank installed decades ago is most likely to still be sitting under the yard, disclosed or not.
Contrast that with a planned community built to city sewer specifications from day one, where the water notice will take thirty seconds to fill out because the answer to every question is no. The friction isn't citywide. It's concentrated in a specific band of Southlake's inventory, and it's exactly the band where estate-level buyers spend the most time.
| What changed in the 2026 TREC disclosure update | Why it matters for a Southlake seller |
|---|---|
| New standalone Water Notice (TREC Form 61-0), mandatory July 1, 2026 | Requires disclosure of any well, in use or not, and whether it's registered with a groundwater conservation district |
| Updated Seller's Disclosure Notice (TREC Form 55-0) | Adds private roads, storage tanks over 500 gallons, and conservation easements to the standard checklist |
| Insurability disclosure | Sellers must state if they've been unable to obtain or renew coverage, a separate issue from water but bundled into the same update |
| Generator disclosure | Permanently installed, built-in generators now require disclosure as an improvement |
The Timeline That Actually Matters Right Now
Because the mandatory date already passed, there's no ramp-up period left to plan around. Every contract signed from July 1 forward uses the updated forms. A seller who lists a Southlake estate property this fall, works through option period, and closes before winter will complete this disclosure at the very start of the process, not as an afterthought. That timing works in a seller's favor if the paperwork is handled early, because a clean, accurate water notice signals to a buyer's agent that nothing is being managed around. It works against a seller who treats the form as boilerplate and checks boxes without confirming what's actually under the lot.
The disclosure is not a warranty. It doesn't certify that a well produces a given flow rate or that a septic system passes inspection. It states what the seller knows. But knowing less than you should, on a property where a title search or a buyer's own due diligence turns up a well the seller never mentioned, is the scenario the form exists to prevent.
Before You List: A Short Check for Southlake Sellers
If your property was built before the city's newer subdivisions, or sits on a larger lot in one of Southlake's custom-built enclaves, a few questions are worth answering before the form goes to your buyer:
- Is there a well on the property, active or not? An inactive well from decades ago still counts. If you genuinely don't know, that's a different answer than knowing and not disclosing, but it's worth a walk of the property and a look at any as-built drawings before you sign.
- Is the lot on septic, and is your maintenance documentation current? If the city's inspection process requires a trip ticket before work can proceed, having that ready before you list saves time during option period rather than during it.
- Does the property draw from an alternative water source alongside municipal service? If so, confirm the cross-connection separation the water department requires is actually in place, not just assumed.
- Has anyone ever leased or sold water rights separately from the land? This is rare in Southlake, but the form asks directly, and the honest answer protects you either way.
None of this requires a hydrologist. It requires an afternoon and, in some cases, a call to the city's building inspections office to confirm what's on file for your address.
Frequently Asked Questions
Does this form apply if my home has always been on city water and sewer? Yes, the form is now part of the standard disclosure package for Texas residential sales generally. For a property with no well, no septic, and no surface water feature, most sections will simply be answered no. The form itself doesn't change based on what's typical for the area, only your answers do.
What if I bought the house years ago and never confirmed whether there's an old well on the lot? The disclosure asks what you know, not what a professional inspection would find. If you have no reason to believe a well exists, you're not required to investigate one into existence. But if you've seen a capped pipe in the yard, an old pump house, or anything that suggests one might be there, that's worth confirming before you sign rather than after a buyer's own inspection raises the question.
Southlake's disclosure landscape just got more specific, and the properties where it matters most are exactly the ones with room to spare, mature trees, and a build date that predates the city's newest infrastructure. If you're preparing to list one of those homes, or you're searching for exactly that kind of privacy and land, Andrea Miranda can walk the property with you before the paperwork does, and make sure what goes on the form matches what's actually under the ground.
