Arizona Water Resources And Issues Border Legislative Conference December 7, 2006.

ArizonaArizona Water Resources Water Resources And IssuesAnd Issues

Border Legislative Border Legislative Conference Conference

December 7, 2006December 7, 2006

Average statewide Arizona monthly precipitation, (bars; left-hand scale) and temperature (line; right-hand

scale) 1971-2000

0

0.5

1

1.5

2

2.5

jan feb mar apr may jun jul aug sep oct nov dec

pre

cip

(in

.)

0

20

40

60

80

100

tem

p (

F)

Precip (in.) Temp (F)

Water Supply of ArizonaWater Supply of ArizonaColorado Colorado River 2.8 River 2.8

MAFMAF

Salt Salt River River 0.9 0.9 MAFMAF

Gila River Gila River 0.3 MAF0.3 MAF

GroundwaGroundwater 3.5 ter 3.5 MAFMAF

Arizona Water SupplyArizona Water SupplyAnnual Water BudgetAnnual Water Budget

Water SourceWater Source Million Acre-Feet Million Acre-Feet (maf)(maf)

% of Total% of Total

SURFACE SURFACE WATERWATER

Colorado RiverColorado River 2.82.8 36.4 %36.4 %CAPCAP 1.61.6 21%21%

On-RiverOn-River 1.21.2 16%16%

In-State RiversIn-State Rivers 1.21.2 15.6%15.6% Salt-VerdeSalt-Verde 0.90.9 12%12%

Gila & othersGila & others 0.30.3 4%4%

GROUNDWATEGROUNDWATERR

3.53.5 45.5%45.5%

EFFLUENTEFFLUENT 0.180.18 2.3%2.3%

TotalTotal

7.7 maf7.7 maf

Sources: ADWR, UofA, USGS

DemandDemand

Industrial .41 maf

5%

Agriculture5.9 maf

77%

Municipal 1.37 maf

18%

Border Profile

• Two thirds of Arizona’s border is under federal jurisdiction as national monuments, forests, wildlife refuges, bombing ranges or are tribal lands

• Significant agricultural and urban water use is therefore restricted to area near Yuma and to the communities of Nogales, Sierra Vista and Douglas

Border ProfileGroundwater Basin

2003 Populati

on

2003Surface Water

Demand (acre-ft)

2003Groundwa

ter Demand(acre-ft)

2050 Populatio

n

Yuma 176,000 788,000 304,000 502,000

Santa Cruz AMA

37,000 20,000 58,500(2025)

Upper San Pedro

82,000 4,500 34,000 110,000

Douglas 28,500 0 95,000 36,500

Yuma BasinCultural Water Demand-2003

• 1.09 million acre-feet used in 2003 by agricultural, municipal and industrial sector– Well pumpage and diversion of Colorado River

contract water– 96% Agricultural Use

• Use not expected to increase• 72% surface water

– 3.5% Municipal Use• Rapidly growing communities of San Luis, Yuma and

Fortuna Foothills• 85% surface water

– .5% Industrial Use• 69% surface water

Santa Cruz AMA

• 37,000 people; population concentrated in Nogales and along the Santa Cruz River

• Large fluctuations in temporary residents

• Nogales, AZ population 23,000

• Nogales, Mexico population 300,000

Nogales

Tubac

PIMA

COUNTY

Rio Rico

SANTA

CRUZ

COUNTY

Amado

Demographics

Santa Cruz AMA Demand

25,800 AF

10,300 AF

7,300 AF

1,500 AF

537 AF

8,600 AF

All water uses

Upper San Pedro BasinCultural Water Demand - 2003

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

Municipal Industrial Agricultural

Water Use Sector

Acr

e-F

eet

Surface water

Groundwater

Douglas BasinCultural Water Demand - 2003

• 60,400 acre feet of groundwater• Irrigation Non-expansion area

– Most of basin is an Irrigation Non-expansion area

– no new lands can be irrigated with groundwater

• 89% Agricultural Use– Water use is increasing

• 11% Municipal Use– Demand is increasing slowly

“Subflow” subsurface water subject to surface water law

Laws governing surface water are distinct from those governing groundwater

Government Framework and Management of Water

Resources

– Surface water• Prior appropriation doctrine

– “First in time, first in right”

– Groundwater• Beneficial use doctrine

– Unlimited ability to pump, so long as use is “beneficial” and “reasonable” (outside AMAs)

– Ability to pump constrained by system of rights and permits (inside AMAs)

Water Management AreasWater Management Areas

Joseph City INA: No new irrigated

lands

Prescott AMA goal: safe-

yield by 2025

Phoenix AMA goal: safe-

yield by 2025

Tucson AMA goal: safe-

yield by 2025

Harquahala INA: No new irrigated

lands

Douglas INA: No new

irrigated lands

Pinal AMA goals:- allow development

of non-irrigation uses

- preserve agriculture as long

as feasibleSanta Cruz AMA goal:- maintain safe-yield- prevent decline of water table

• Underground Storage– CAP and effluentCAP and effluent– 55 Active Permits55 Active Permits– Permitted volumes 150 af to 200 Permitted volumes 150 af to 200

kaf/yearkaf/year– Most recharge facilities are located Most recharge facilities are located

within AMAs; especially the Phoenix AMAwithin AMAs; especially the Phoenix AMA

• Conservation• Reuse• Augmentation

Challenges: Future Water Challenges: Future Water SuppliesSupplies

Future Water SuppliesFuture Water SuppliesUnderground Storage - BenefitsUnderground Storage - Benefits

• Long-term storageLong-term storage

• Large capacityLarge capacity

• Little evaporative Little evaporative lossloss

• Reduces risk of Reduces risk of subsidencesubsidence

Water Management InitiativesWater Management Initiatives

• ConservationConservation– Technology TransferTechnology Transfer– Education and Public InformationEducation and Public Information

• Effluent ReuseEffluent Reuse• Augmentation and Water TransfersAugmentation and Water Transfers

– Agriculture to Urban Water TransfersAgriculture to Urban Water Transfers– Desalinization in the Future?Desalinization in the Future?

Challenges: Indian Water Challenges: Indian Water SettlementsSettlements

• 28% of Arizona Land held in Trust 28% of Arizona Land held in Trust for the benefit of Native Americansfor the benefit of Native Americans

• Recently Settled:Recently Settled:– Gila River Indian Community and Gila River Indian Community and

Tohono O’odhamTohono O’odham635,000 acre-feet/year to Gila 635,000 acre-feet/year to Gila

River River Indian CommunityIndian Community-- Fort Yuma – Quechan-- Fort Yuma – Quechan

• Pending settlements; Navajo, Hopi, Pending settlements; Navajo, Hopi, White Mountain Apache and San White Mountain Apache and San Carlos ApacheCarlos Apache

Challenges - Surface Water Challenges - Surface Water AdjudicationsAdjudications

Gila RiverGila River

Little Colorado Little Colorado RiverRiver

Definition: “A general stream Definition: “A general stream adjudication is a judicial adjudication is a judicial proceeding in which the nature, proceeding in which the nature, extent, and relative priority of extent, and relative priority of water rights is determined.” water rights is determined.”

•Court must define the legal Court must define the legal difference between surface difference between surface water and ground water water and ground water before rights can be before rights can be determineddetermined

Gila & Little Colorado cases are still Gila & Little Colorado cases are still in Phase 1 after 30+ yearsin Phase 1 after 30+ years

Challenges - Colorado RiverChallenges - Colorado River

•Arizona’s Central Arizona Project Arizona’s Central Arizona Project water supply has the most junior water supply has the most junior priority.priority.

•Drought may cause water supply Drought may cause water supply shortageshortage

•Discussions are underway on Discussions are underway on supply augmentation, supply augmentation, conservation and system conservation and system management to meet demands management to meet demands and obligationsand obligations

Upper Basin (7.5 Upper Basin (7.5 mafmaf)

Lower Basin (7.5 Lower Basin (7.5 maf)maf)

California – 4.4 mafCalifornia – 4.4 maf

Arizona – 2.8 mafArizona – 2.8 maf

Nevada – 0.3 mafNevada – 0.3 maf

Mexico 1.5 Mexico 1.5 mafmaf

ArizonArizona a

Upper Upper Basin Basin – 50 – 50 kafkaf

Lee Lee FerryFerry

Colorado River Colorado River Compact & Treaty Compact & Treaty

AllocationsAllocations

• Arizona Drought Preparedness Plan adopted in 2004 to identify drought impacts, prepare drought response and reduce drought impacts

• Water providers must prepare drought plans

• Drought monitoring is ongoing

Challenges -DroughtChallenges -Drought

• Colorado River - federal jurisdiction and international treaty

• Population growth is impacting shared and limited water supplies

• Limited hydrologic information for many border basins hinders water planning and management

• Water quality issues in the Douglas/Agua Prieta and Ambos Nogales pose a threat to local water supplies

• Lack of access to renewable water supplies to support increasing demand

Challenges - BorderChallenges - Border