Water Resources 101

Arizona’s Municipal:

Water Future

Water Resources 101

Arizona’s Municipal Water Future

Questions for the near and long-term:

Where will our water be used?

Where will it come from?

When will we run out?

Water Resources 101

Water Resource Planning Drivers

Water Planning in the Western States:•Growing population•Drought and climate change•Overuse of groundwater supplies•Endangered species concerns•River ecosystem protection•Over-appropriation•Competing Uses

Overview of Water Planning in Western StatesNew Mexico Office of the State EngineerFebruary 2009

Water Resources 101

Status and Trends

Arizona’s population will continue to grow – and spreadClimate change may impact supply reliabilityNear-TermExisting Supplies will become fully utilizedNew water transfer projects will be implementedLong-Term“Next bucket” will take decades to plan/implementWhat is out there? What steps are being taken? Planning + Investment = Reliability

Water Resources 101

Where’s the Demand?

“Red Dot” maps (source: Maricopa Association of

Governments)

2010 through 2040Population projections converted to demands for water

How does projected water demand compare to water availability?

Slide 6 of 34

2010

Water Resources 101

Population Growth

Water Resources 101

Population & Municipal Demand Trends Total State population projected to grow

from 6 million to 12.8 million by 2050 Municipal water demand to increase by

110% - to a total of almost 3 MAFRegional Notes Pinal County projected to grow by 400% Water usage rates not necessarily intuitive:

highest per capita use in Yuma County at 250 GPCD

State-wide municipal water use still dominated by three-county CAP service area: 85% of total in 2050

Water Resources 101

Climate Change in the News

Do we need to know the cause to plan for

the effects?

Water Resources 101

Climate Change DriversRapidly growing population “in all the wrong

places” east, central and west coastal areas and desert.

Aging infra-structure that is stressed to provide either water supply or energy supply during periods of even moderate climate deviationUrban Heat Islands (UHI) associated with large population areas are a real “man-made” climate change impact.

Beyond Stationarity – Climate changes due to natural variability are far beyond 30-yr climate design assumptions.

Water Resources 101

Spaghetti Planning?IPCC 4 multi-model ensemble

Water Resources 101

Cone of Uncertainty

Climate modeling suggests natural variability explains little for future climate…

Natural Variability

Time

Climate Model Projections

Cone of Climate Uncertainty Waage, 2009

Water Resources 101

Changes ahead

Water Resources 101

Where’s the Surface Water?

Salt/Verde System & SRP

Water Resources 101

Where’s the Surface Water?

Colorado River & CAP

Water Resources 101

Where’s the Groundwater?

AMAs & Basins

Water Resources 101

GroundwaterAvailability

Extra: more water available after 200 yearsModerate: some water, but not a lotRisk: about to run outEmpty: overdraft will occur if not carefully managed

Water Resources 101

Groundwater Availability

Dark Red: Stressors are causing overdraft conditionsWhite: Projected stressors are not causing problems

Opportunities for inter-basin transfers & new pipelines?

Opportunities for shifting projected populations based upon water availability?

Water Resources 101

Water Resources 101

What About Reclaimed?Current• Landscape and golf course irrigation• Groundwater recharge • Wetlands, wildlife habitat, stream

augmentation• Industrial / power plant cooling processes• Surface irrigation of orchards and vineyards• Vehicle washing

Water Resources 101

Supply Augmentation and Demand Management

•Conservation•Water Harvesting•Gray water•System Efficiency

Balanced Water Supply

Groundwater

Surface Water

Reclaimed Water

HomesCommercial

Losses

Industry

Parks

New Supplies

Water Resources 101

So, What are Some of the Current Plans and Possibilities to Meet Demands?

Water Resources 101

Proposed GroundwaterTransfers

Red Gap RanchBig ChinoMcMullen, Butler, and HarquahalaBlack MesaBrackish Supplies

Red Gap Ranch

Big Chino

Black Mesa Pipeline

Wilcox Basin

McMullen, Butler, and Harquahala

Yuma Brackish

GW

Water Resources 101

Reclaimed Water Prospects

Effluent exchangesCAGRD purchasesIndian water settlementsGrowing reclaimed water service areas

Water Resources 101

Surface Water Concepts

C.C. Cragin in Payson (East Clear Creek Basin)Metro Water District, Marana, Oro Valley, and Flowing Wells Irrigation District (Allocated CAP)Green Valley, Sahuarita, and Surrounding Interests (Allocated and Unidentified CAP)Sierra Vista CAP Extension (Unidentified CAP)Lake Powell Pipeline in Northern Arizona (Unidentified Colorado River Water)

Colorado River/CAP are Fully Allocated

Water Resources 101

What’s Next?

•Allow/encourage water availability to influence where development occurs?•Conservation by design (increase the way infrastructure shapes water use)?•Changes to rules/regulations to increase Arizona’s flexibility to meet water demands?•Move water from where it is, to where it needs to be – large water transfer projectsWhat about the long-term?•Developing the “Next Bucket”

Water Resources 101

Augmenting the State’s Supplies:The “Next Bucket”(s)

Surface Water•ADD Water

Reclaimed Water•New uses•Indirect Potable Reuse

Seawater Desalination

………Salmon, Catfish, and Polar Bears?

What supplies areout there?

Water Resources 101

ADD Water

CAP created Project Acquisition, Development and Delivery (ADD) Water•Response to its 2006 Strategic Plan to:

• Establish a collaborative process• Encourage fair competition• Eliminate perceptions of unfair advantage

Determine when new supplies need to be acquired and what

entities get those supplies

Water Resources 101

Reclaimed Water

Water Resources 101

Seawater Desalination

•Mexico, California, or both?•Technologies•Conceptual Study at Rocky Point

Water Resources 101

Grand Designs…

Salmon?

Importation from the Yukon and/or Columbia RiversCatfish?

The Mississippi River BasinPolar Bears?

What about towing icebergs (get them while they last!)

Water Resources 101

Arizona’s Municipal Water Future

Questions for the near and long-term:Where will our water be used?State-wide, but 85% in Maricopa, Pinal, and

PimaWhere will it come from?Groundwater, Surface Water, Recycling, and

Beyond

When will we run out?When we decide to stop planning and fail to invest in our water infrastructure

Answers