As Texas continues to grow, ensuring a reliable water supply for new subdivisions is more important than ever. One key regulation developers must understand is the Groundwater Availability Certification (GAC) a requirement now embedded in state law and local platting practices. Whether you’re preparing land for residential lots, commercial projects, or mixed-use developments, GACs play a central role in securing approval for your project. TCEQ+1
A Groundwater Availability Certification is an official statement prepared by a licensed professional that confirms adequate groundwater exists beneath a property that will serve as the primary water supply for a proposed subdivision. This isn’t optional in Texas anymore — it’s a mandated part of the platting process for land where groundwater will be used to supply water. TCEQ+1
Prior to January 2024, groundwater certifications were generally voluntary in many jurisdictions. But as of January 1, 2024, municipalities and counties must require a certification of groundwater availability for proposed subdivisions where groundwater is the intended source of water — making this a crucial step before plat approval.
Failing to secure a valid certification can delay or derail plat approval, costing time and money. Because of this, savvy developers integrate these studies early in due diligence.
By rule, a GAC must be prepared and signed by a:
✔ Texas-licensed professional engineer (P.E.)
✔ OR Texas-licensed professional geoscientist (P.G.)
Professionals use site-specific groundwater data, aquifer information, and projected water demand estimates to certify that the resource is sufficient for both short-term and long-term needs.
Here’s how the certification and submission process typically works:
Data Collection:
Drilling tests, aquifer testing, well data, water quality, and water level measurements are gathered.
Analysis:
Groundwater availability is analyzed for at least 10- and 30-year horizons based on build-out water demand.
Form Completion:
The official TCEQ Certifications are completed.
Certification Submission:
Submit the forms to the municipality or county authority responsible for approving your plat.
Plan Early: Groundwater studies can take weeks to months — begin them during due diligence.
Work with Experienced Professionals: Use licensed engineers or geoscientists familiar with Texas GAC requirements.
Understand Local Rules: Some counties or municipalities may have additional requirements or waiver provisions under certain conditions.
Groundwater Availability Certifications are more than a regulatory checkbox — they are a critical step in ensuring a sustainable, approvable development in Texas. By understanding the process, timelines, and requirements, developers can reduce risk, avoid delays, and move their projects forward with confidence.
At Talon/LPE, our groundwater professionals combine sound science, local aquifer knowledge, and regulatory expertise to deliver clear, defensible certifications that stand up to agency review. Whether you are in early due diligence or preparing for plat submission, our team is ready to support your project with data-driven insight and practical solutions.
Let’s use science to secure your water supply — and keep your development moving.
Contact Talon/LPE to discuss your Groundwater Availability Certification needs.