Rainwater Resources
Curated links to Texas and national guidance, codes/standards, and data sources to help you plan and learn more about rainwater harvesting.
Supporters
These organizations support the development of open, data-driven tools that help Texans evaluate rainwater harvesting as a reliable water supply option.
How to use these links
Start with Texas agencies for local guidance. If you’re designing a system or working with a plumber, check the codes/standards section.
Have a link to add?
If you know a good Texas incentive, training, or installer resource, send it my way.
Suggest a ResourceTexas resources
State agencies, extension services, and local guidance.
Texas Water Development Board (TWDB)
Guidance, manuals, and background for rainwater harvesting in Texas.
Texas A&M AgriLife Extension
Practical how‑tos, trainings, and the Texas Manual on Rainwater Harvesting.
TCEQ: Rainwater Harvesting
Program info, public water system considerations, and guidance.
Local Installers
Browse a growing directory of rainwater harvesting installers and service providers in Texas.
Incentives Directory
Explore organizations and programs that may offer rainwater harvesting incentives.
National and professional resources
Standards bodies, training organizations, and best-practice programs.
Know Your Water
WaterScore translates complex federal water quality datasets into plain-language grades and recommendations — so anyone buying, renting, or living in a home can understand what's actually in their water.
ARCSA
American Rainwater Catchment Systems Association: training, standards, and advocacy.
EPA WaterSense
Best practices for outdoor water efficiency and program resources.
Codes and standards
Where to start when you need the formal “rules of the road.”
ARCSA/ASPE Standards
Technical standards for design and installation of catchment systems.
Plumbing codes
Local jurisdictions may adopt the UPC, IPC, or amendments for non‑potable and potable systems.
Datasets and tools
Public datasets used for precipitation estimates and climate context.
Texas Data & Science
Daily precipitation maps and data visuals for Texas rainfall conditions.
Additional Calculators
Use custom rainfall and demand inputs for projects outside the Texas coverage area or for user-supplied rainfall records.
PRISM Climate Group
High‑resolution gridded climate data used for precipitation estimates.
NOAA NCEI
Climate Data Online for station and gridded precipitation records.
Texas Mesonet
Interactive mapping app for weather stations and rain gages across Texas.
Explore your site’s potential
Enter your address, roof area, and typical monthly use to see a data‑driven recommendation.
Open the Calculator