Two tracts on the same Argyle road can carry two completely different water stories. One sits inside a certificated service territory and closes with a meter number. The other sits half a mile away, outside the boundary, and closes with a decision about drilling depth. The listing photos will not tell you which one you are under contract on. Neither will the address.
The single most consequential piece of due diligence on an Argyle acreage purchase is figuring out where the CCN line runs relative to the tract. That answer sets the utility path, the build timeline, and roughly $8,000 to $30,000-plus of construction cost that has nothing to do with the house itself.
The CCN Line Is the First Question
A Certificate of Convenience and Necessity is the state-granted service territory a water utility holds. Inside the line, the utility is obligated to serve. Outside, it is not, and there is no automatic right to a tap. In the Argyle corridor, two nonprofit water supply corporations divide most of the map, and neither one respects town limits.
Argyle Water Supply Corporation has served Argyle and surrounding areas since 1963. To the south and east, Cross Timbers Water Supply Corporation, which operated as Bartonville Water Supply Corporation for most of its history and still runs from 2032 E Hickory Hill Road in Argyle, covers about 20 square miles of south-central Denton County across roughly 2,635 connections in Bartonville, Double Oak, Copper Canyon, portions of Highland Village and Flower Mound, and unincorporated pockets in between. The two systems share an emergency inter-connect, but they are separate utilities with separate membership and separate line extension policies.
Everywhere the CCN map has a hole, water comes from a private well.
Three Water Paths, Three Different Contracts
Before writing an offer, place the tract on one of three paths. Each path implies a different set of contingencies, timelines, and pre-close verifications.
- Inside AWSC territory. Confirm the specific service address is a current member, request the account transfer packet, and verify the meter size against planned use. Irrigation and equestrian demand on a five-acre lot is not the same as domestic demand, and line pressure at the tap end of a rural main is worth measuring, not assuming.
- Inside Cross Timbers territory. Same drill, different utility. Cross Timbers has been extending and upgrading distribution lines through Bartonville, Double Oak, and Copper Canyon over the last decade, and a tract that showed as "no service available" three years ago may now have a main at the road. That is a phone call, not a portal query.
- Outside both CCNs. The tract will need a private well, and the transaction changes shape. The seller's existing well report, the driller's licensure, the North Texas Groundwater Conservation District registration status, and the option-period window for a well yield test all become active variables.
The first hour of due diligence is spent identifying which path applies. The rest of the option period is spent working that path to a decision.
The 17.36 GPM Threshold Decides Your Build Scope
For tracts on the private-well path, the governing authority is the North Texas Groundwater Conservation District, created by SB 2497 in 2009 to regulate groundwater in Collin, Cooke, and Denton counties. The district's rule structure is straightforward once you see the pivot point.
New wells with a capacity under 17.36 gallons per minute are exempt from metering, production reporting, production fees, and permitting. Wells above that threshold are non-exempt, which triggers a Production Permit, an installed totalizing meter, and monthly usage reporting to the district. Wells with an aggregate production capacity of 200 gpm or more require a Hydrogeological Report before drilling. The district does not require a minimum tract size to qualify for the exemption.
What that threshold actually means for a buyer is a build-scope filter. A single-family home with normal domestic use and a modest irrigation program sits comfortably inside the exempt bucket. A larger equestrian operation with multiple pastures on drip, a guest house or barndominium with its own service, and heavy landscape irrigation can push aggregate capacity across the line into a permit-and-meter regime the buyer did not price. The question to answer before writing is not "can we drill a well" but "at what capacity do our plans push us into non-exempt territory, and does that change the economics."
Two verification steps make this concrete. First, the driller must file a State of Texas Water Well Report with TDLR within 60 days of completion, and older well reports are searchable through the TCEQ Water Well Report Viewer for wells drilled between 1966 and February 2001 and the Texas Well Report Submission and Retrieval System for anything after. Second, for tracts with an existing well, the seller can and should provide that report. If they cannot, the buyer can retrieve it themselves before the option period expires.
OSSF Adds a Second Layer, and 10 Acres Changes It
Argyle acreage does not sit on municipal sewer. Every tract outside a limited pocket of public collection uses an On-Site Sewage Facility, which is permitted through Denton County Public Health at (940) 349-2900, acting as the TCEQ Authorized Agent under 30 TAC Chapter 285.
The default path requires a site evaluation with soil analysis and percolation testing, a licensed installer, and inspection before use. New installation permits typically run $200 to $500 and the county's process generally takes two to six weeks depending on soil scheduling and application completeness. The design implications are real. Denton County straddles Blackland Prairie clay in the east and Cross Timbers sandy loam in the west, and expansive clay percolates slowly, which pushes some sites toward aerobic systems rather than conventional gravity drainfields. That is a cost delta and a footprint delta.
The lever is the 10-acre single-family exemption. Properties of 10 acres or more with a single-family dwelling may qualify for exemption from the standard OSSF permitting process, which meaningfully changes design flexibility, siting constraints, and timeline on larger tracts. Read that as a bright line to verify with the county, not a shortcut to assume. If a tract is 9.7 acres, the surveyor's number matters. If it is 12.4, the exemption analysis is worth the phone call before the option period runs.
What to Verify Inside the Option Period
The option period is the only window in which these questions are cheap to answer. Miss it, and every answer costs earnest money or contract amendments. The sequence below is the one this practice runs on Argyle acreage transactions.
- Confirm the CCN. Call AWSC and Cross Timbers with the exact address and ask whether it sits inside the certificated territory and whether service is currently available at the frontage.
- Pull the well report if a well exists. Ask the seller. If they do not have it, retrieve it from the TCEQ or TDLR databases using the coordinates.
- Register the well with NTGCD if required. Even exempt wells fall under the district's jurisdiction for registration in most cases. The district staff will confirm status by parcel.
- Match capacity to plans. Add up domestic use, irrigation acreage, livestock, and any accessory dwelling. If aggregate capacity sits near 17.36 gpm, plan for the non-exempt path or scale the plan.
- Order an OSSF site evaluation. A licensed site evaluator can run soil analysis and percolation testing inside a normal option period. On tracts near 10 acres, verify exemption eligibility with Denton County Public Health in the same call.
- Confirm the driller's TDLR license. New wells must be drilled by a licensed driller who files the State Well Report within 60 days. Verifying the driller is a five-minute step that closes a real risk.
- Price the delta. Well drilling in Texas ranges roughly $8,000 to $30,000-plus in 2026 depending on depth and aquifer. If the tract is a private-well tract, that number belongs in the offer analysis, not in the surprise column at closing.
FAQ
Is a private well cheaper than CCN water over the long run on a 10-acre Argyle tract?
Not necessarily. The upfront cost of a well runs $8,000 to $30,000-plus, plus pump, pressure tank, and treatment for iron and hardness common in Denton County groundwater. CCN service carries a monthly bill and, in some cases, a line extension or membership fee. The comparison is site-specific and should be run before writing, not after.
Does the 10-acre OSSF exemption mean I skip inspection entirely?
No. It means the property may qualify for exemption from the standard permitting process for a single-family dwelling under 30 TAC Chapter 285. The system still has to function, the design still has to be sound, and county rules still apply. Verify eligibility and the specific scope of the exemption with Denton County Public Health directly.
If my well pumps under 17.36 gpm, do I still register with NTGCD?
Exemption from metering, fees, and production permitting does not always mean exemption from registration. The district's staff can confirm the specific requirement for a given parcel and the current registration form. That call belongs on the option-period checklist.
Can I switch from a private well to CCN service later?
Only if the tract is inside a CCN territory that will extend service, and only on the utility's terms. Line extension costs are borne by the applicant in most cases, and the economics rarely work in reverse. Decide the water path once, at purchase.
The water path is the piece of Argyle acreage due diligence that separates a clean close from a renegotiation. It is not the piece you want to figure out after the option period expires. If you are under contract, or close to it, on a tract in Argyle, Bartonville, Copper Canyon, or the unincorporated pockets in between, Ryan Stoddard Real Estate works these questions on a deal-by-deal basis. Schedule a free consultation before you write.
