Water Resources Management at the Mexican Boundary with

the USA

Javier Aparicio

Mexican Institute of Water Technology

Ministry of Environment and Natural Resources

México

Instituto Mexicano de Tecnología del Agua

Deals primarily with water related issues in order to help reaching the sustainable development for the country, by conducting research and technological development (R&D) in collaboration with public and private institutions, universities and other research centers such as NGO’s.

Four main research divisions

• Hydrology

• Water Quality

• Irrigation and drainage

• Hydraulics

• Professional development

In the near future, it is expected that conflicts between neighbour municipalities, counties and even countries will be related to water.

To avoid that, it is necessary to create transboundary water use policies in which all the parts involved agree to make the efficient use and proper long and short term planning.

• 3000 km

• 14 cities

• 10.6 million in 2000

• 55% US, 45% México

• 14 million in 2020

México/USA Boundary

Watersheds México/USAWatersheds México/USA

N

WYOMING

COLORADO

U T A H

CALIFORNIAARIZONA

NUEVOMEXICO

TEXASSONORACHIHUAHUA

COAHUILA

DURANGO NUEVOLEON

GULF OF

MEXICO

OCEANPACIFIC

NEVADA

1944 Treaty

BRAVO/GRANDE RIVER WATERSHED

TOTAL = 444,560 km2

U S A = 229,798 km2

MEXICO = 214,762 km2

COLORADO RIVER WATERSHEDTOTAL = 634,840 km2

U S A = 631,000 km2

MEXICO = 3,840 km2

TIJUANA RIVER WATERSHEDTOTAL = 4,424 km2

U S A = 1,221 km2

MEXICO = 3,203 km2

Colorado River• 634,840 km2

• 7 USA States: Colorado River compact

• 2 Mexican States

Gulf of California or Gulf of Cortés

Colorado River flows

•Droughts are shared

Hoover Dam

Glen Canyon Dam

•One of the most exploited rivers in the world: 20,700 5,200 hm3 in 100 years

•1,850.2 hm3/yr to México; 2097 when there are excedents

1000 acre-ft=1.233 hm3

•Nearly 100% of water is used for agriculture & urban supply

Droughts, Colorado River

• In case of extraordinary droughtextraordinary drought or a serious accident in the irrigation system in the USA which would prevent delivering the guaranteed volume, the assigned volumes to Mexico would be reduced in the same proportion as the consumption reduction in the USA.

Colorado River: Salinity

• Salinity not in the Treaty

• 1961: Increase in salinity above 2,500 ppm

• IBWC Negotiations: Act 242 (1973)

• Bypass channel

• Salinity < Imperial Dam +121 ppm; higher at San Luis

Imperial Valley

Mexicali Valley

Imperial dam

Morelos dam

San Luis Río Colorado

500

600

700

800

900

1000

1100

1200

1300

1400

1500

1600

1700

1800

E-

96

E-

96

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96

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96

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M-

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J -

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96

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J -

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J -

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J -

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E-

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J -

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S-

98

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98

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98

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98

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98

E-

99

F-

99

M-

99

A-

99

M-

99

J -

99

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99

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99

A-

99

S-

99

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99

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99

E-

00

F-

00

Year

Colorado River: Salinity

Source: CILA

San Luis

Morelos

Imperial

Delta Region

• One of the biggest desert estuaries in the world

• 780 000 ha

• Highly diversified collection of plants, birds and marine species

•Dry and dead system of small wetlands and salt marshes

•Highly salinized desert

• Floods, surplus, return flows

• 60 000 ha restoration

• Significant wetland ecosystem in SW USA and NW México in danger

70´s and 80´s Last 2 decadesBefore 1930

Delta Region

• Significant population increase

• Pressure over land, water and other resources

• Permanent flows vs. Interim Surplus Criteria

• Legal issues

Near future

SEA

OF CORTÉS

LAGUNA

SALADA

SANTA CLARA

SLOUGHALTAR DESERT

IMPERIAL VALLEY

SALTON

SEA

MEXICALI VALLEY

Actions

• Establishment of the Alto Golfo de California y Delta del Río Colorado Biosphere Reserve

• Wastewater treatment plants in Border Cities and recycling• Efficient water use programs• Legal framework modifications: New National Water Law

– Ecological priority– Incentives to water consumption reduction

• Program Border XXI– Public participation– Capacity building– Interinstitutional cooperation

• Binational workgroups for R&D

Bravo/Grande River

• Boundary: 2,001 km

• Total runoff : 11,000 hm3/year

• Total storage capacity: 23,000 hm3

• 1944 Treaty: Fort Quitman to mouth

P LUIS L. LEÓN

P FRANCISCO I. MADERO

P LA BOQUILLA

P SAN GABRIEL

P LA AMISTAD

P VENUSTIANO CARRANZA

P FALCÓN

P MARTE R. GÓMEZ

P EL CUCHILLO

P SAN

MIGUELP LA FRAGUA

Río Salado

Río C

onch

os

Río San Pedro

Río

Flo

rido

Río San Diego

Río San Rodrigo

Río

San

Jua

n

Río Conchos

Río Chuviscar

Arroyo Las Vacas

Río Escondido

Rio B

ravo

DR CDDR CDJUÁREZ 009JUÁREZ 009

DR BAJO RÍODR BAJO RÍOCONCHOS 090CONCHOS 090

DR DELICIASDR DELICIAS005005

DR RÍODR RÍOFLORIDO 103FLORIDO 103

DR PALESTINADR PALESTINA006006

DR DONDR DONMARTÍNMARTÍN

004004DR ACUÑADR ACUÑAFALCÓN 050FALCÓN 050

LASLASLAJASLAJAS031031

DR BAJO RÍODR BAJO RÍOSAN JUAN 026SAN JUAN 026

DR BAJO RÍODR BAJO RÍOBRAVO 025BRAVO 025

P CENTENARIO

P CHIHUAHUA

P EL REJÓN

Fort Quitman

Agricultural use, Bravo Basin

Bravo/Grande River

USAC

onch

os

Sal

ado

Fort Quitman

Gulf of México

Gauged rivers

Bravo/Grande

1/3 US

2/3 México

•74 hm3/yr at Juárez (1906)

•431.7 hm3/yr in 5-yr cycles

•1953-2002: 26 periods

•Cycle 25 completed in 2001

•Deficit in cycle 26

•Droughts are not shared

Falcón Dam

1/2

1/2 1/2

1/2

La Amistad Dam

Droughts, Bravo/Grande River

• In case of extraordinary droughtextraordinary drought or a serious accident in the Mexican hydraulic system which would prevent Mexico to deliver such volume, any undelivered volume at the end of the 5-year period would be distributed in the following period with water from the same tributaries.

Actions• Wastewater treatment plants

in Border Cities• Efficient water use programs • Binational workgroups for

R&D• Río Bravo water distribution

rule• Irrigation modernization and

technology improvement in Conchos River Basin

Río Bravo water distribution rule

• Define Extraordinary drought

• Distribute US assignment among Mexican tributaries

• Propose to subject deliveries to US with the same deficit restrictions as Mexican irrigation assignments

• Consensus building on distribution rule among users

Modernization and technology improvement, Conchos Basin

•Channels and network lining

•Control structures and wells rehabilitation

•Low pressure, drip and sprinkler systems

•Land leveling

•Real-time irrigation forecast

•Efficiency: 33 55%

•Recover 396 hm3/yr in 4 years

•2002-2006, US $150 million

•NADBank Fund and Federal investment

Water quality, Tijuana• 32 hm3 of treated

residual water with organic contaminants to the Pacific Ocean

• Industrial residuals discharges 8 hm3/year.

• Volumes generated are higher than plant capacity: serious pollution problems

Transboundary aquifers

Mapa de la región

1. Mexicali Valley2. Sonoita River3. Santa Cruz River4. San Pedro River5. Conejos-Médano aquifer6. Juárez Valley7. La Amistad observation wells

N

Chihuahua

Coahuila

N. L

eón

Tamaulipas

Sonora

Baj

a C

alifo

rnia

Nte

1

3 45

6

7

2

• Mexicali: Recharge/ exploitation: 150/ 102 hm3; All-American channel lining?

• Juárez Valley: Drawdowns > 45 m; quality problems

Conclusions

• México and USA share a politically, sociologically and hydrologically complex and rapidly evolving boundary

• International agreements have been the result of long negotiations made in good will and with the benefits of both countries in mind: examples by other Countries

Conclusions• Population growth and comprehensive water use:

careful joint water resources management in the boundaries

• Sustainable development binational plans, including Colorado Delta ecology

• Integrated international hydrometeorological information system along the Border

• Efficient water use programs

• Binational R&D programs