A defined look at water terminology

Published Dec 27, 2022

The water world is complex, diverse, and deep in terminology, which can confuse anyone who isn’t submerged in it regularly. When discussing anything about water – water quality, water sources and supplies, water management and policies, and the quality and delivery of your water – you are bound to run into acronyms as well as some words and phrases that sound foreign in regular conversations. So, we’re here to help translate.

Understanding and relating to water information is crucial to participating in the ongoing discussions about how Arizona can ensure we all have clean, reliable, affordable water supplies for the long term. Our AMWUA Water Glossary aims to provide clear and understandable definitions of many commonly used water terms to help everyone better understand Arizona water. We hope it provides insight and understanding into terminology that you can utilize when it comes to talking and reading about all things water in our State.

Here are a few examples of how the AMWUA Water Glossary is helpful:

Water Sources
It’s important to note that while each of the AMWUA cities has diverse supplies, each one is unique and utilizes its supplies to best suit its residents and commercial customers. Having more than one water source  creates a more robust and reliable water supply for our communities. That also benefits the economy of the Valley by ensuring a more sustainable way of life for everyone here in the desert.

Arizona has four critical sources of water:

Colorado River Water: Water from the main stem of the Colorado River. Arizona shares the Colorado River with California, Nevada, New Mexico, Utah, Wyoming, Colorado, and Mexico.

Groundwater: Water under the earth’s surface that fills the pore spaces between soil particles and fractured rock.

Recycled Water: Water sent down the drain that is treated to a very high quality to extend and expand its reuse.  The term is used to convey the value of this water as an important water supply. 

Surface Water: Waters that are generally found in springs, streams, rivers, lakes and ponds, canyons, ravines, or other natural channels above ground. 

Water Measurements
Understanding water news or reports can be challenging, given the different measurements  used. Like we have feet, kilometers, and miles for distance, water is also measured by varying units depending on the context.

Acre-foot: A measurement of water quantity equal to 325,851 gallons (enough to cover one acre of land in water one foot deep).

Gallons Per Capita Per Day (GPCD): The average quantity of water each person uses in one day. ADWR sets GPCD targets for water providers in the five AMAs.

Water Agencies 
Agencies regulate all aspects of water In Arizona, but often they are only referred to by their acronyms.

ADEQ (Arizona Department of Environmental Quality): The state agency responsible for oversight, regulation, and enforcement of Arizona’s water quality regulations. ADEQ regulates groundwater, surface water, and recycled water.

ADWR (Arizona Dept of Water Resources): The state agency, created in 1980 by the Groundwater Management Act, designated to implement the State’s water laws. ADWR oversees Arizona’s water supplies and supports statewide and local water planning efforts. 

Water Infrastructure Finance Authority of Arizona (WIFA): WIFA is a State Agency that provides financing assistance for the construction, rehabilitation, and/or improvement of drinking water, wastewater, wastewater reclamation, and other water infrastructure projects. In 2022 the Legislature greatly expanded WIFAs authority to include augmentation and appropriated over $1 billion to the agency. 

Water Policies and Laws
In Arizona, we hear important acronyms for laws, policies, and programs that have been put in place to regulate and manage water across the State and beyond.

Assured Water Supply Program (AWS): A set of consumer protection regulations that apply within the five AMAs based on the principle of “water first, then development.” Before a developer can sell subdivision lots, they must meet the Assured Water Supply criteria, including having access to enough water to last 100 years. The AWS Program is the basis for Arizona’s long-term sustainable growth.  

DCP (Drought Contingency Plan): An agreement between the seven Colorado River Basin States that adds additional water reductions on top of the 2007 Interim Guidelines in times of shortage. 

GMA (Groundwater Management Act): Enacted by the Legislature in 1980 to address the State’s problem of groundwater depletion.

While we continue to dig deeper into all things water-related weekly with our AMWUA Blog , we encourage you to sign up to learn more about critical water issues, local water management strategies, water innovation projects, and conservation. We hope the water glossary provides a simple and more clearly defined look at important terminology and acronyms used when talking about water in Arizona. We acknowledge that the world of water is far from simple, so we recommend you keep our glossary  on hand for the next time you discuss water, which we hope is often. After all, water plays a vital role in our collective long-term sustainability and continued prosperity here in Arizona.

For additional water terminology, ADWR has compiled a Primer on Water Terminology regarding the Colorado River for you to peruse.

For over 50 years, the Arizona Municipal Water Users Association has worked to protect our member cities’ ability to provide their communities with assured, safe, and sustainable water supplies. For more water information, visit .