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How compacts work – The Colorado River experience. Colorado River Compact (1922) Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming – and U.S. Allocates waters based on future needs and water-use priorities.
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How compacts work – The Colorado River experience • Colorado River Compact (1922) Arizona, California, Colorado, Nevada, New Mexico, Utah, and Wyoming – and U.S. • Allocates waters based on future needs and water-use priorities. • After it was ratified, Congress agreed to build Hoover Dam (1928). • Arizona refused ratification until 1944, resented “inequitable division of its share of the lower Colorado.” • Major issues: • Mexico’s share of the river? • How determine how much water is available – science and policy?
Colorado River basin Compact (modified from Harding et. al 1995)
Ongoing challenges for the Colorado River compact • How much water is available? Compact assumes 7.5 million acre-feet in upper and lower basins , rest for Mexico (16.5 MAF total) – not true most years (closer to 11 million acre-feet). • Mexico’s share: (1944 treaty – 1.5 million acre ft./year). Desalination plant built in 1970s. Deliveries reliable, but problematic. • Arizona vs. California: (1963 Supreme Court decision) – “prior appropriation” doctrine does not apply to “lower basin” states); allowed U.S. government to build Central Arizona Project – to divert water to Phoenix, Tucson (1968) – forced CA to reduce water use to 4 million acre-feet, and decline over time. • 1 acre-foot = 386,000 gallons, or enough water for a family of four/one year
Southern California Distribution of Colorado River Compact water KEY: MWD – Metropolitan Water District (LA, Orange, San Diego, portions of Ventura, Riverside & San Bernardino Counties) CVWD – Coachella Valley Water District IID – Imperial Irrigation District PVID – Palo Verde Irrigation District CRA – Colorado River Aqueduct
Other compacts, other challenges • Apalachicola-Chattahoochee-Flint water dispute: (began 1997). • Centered on three rapidly growing states; one large metro area (Atlanta). • Persistent drought – since 1980s worsens conflict, make negotiations to share water necessary. • 1st major U.S. water dispute in a generation not in West. • Led to first new river basin compact in over 30 years. • Compact will NOT take effect until three states agree on an allocation formula – they’ve been unable to agree for 13 years!
Apalachicola-Chattahoochee-Flint River Basin • 2.6 million depend on basin for supply , 75% live in metro Atlanta. • Serves urban needs , agriculture, fisheries. • Severe impacts from runoff, impoundment, channelization. • Atlanta near source of Chattahoochee; a small volume river! • Inflow to Gulf important; major source of domestically harvested seafood – 15% of nation’s oyster harvest; 80% of Florida’s.
Drought in the South “Southeast drought hits crisis point” October 21, 2007 Lake Lanier, Chattahoochee River The Southeast's worst drought in more than a century is forcing parched states and communities (like Atlanta) into crisis measures to conserve water and fight for access to more . . . "This idea of wait-and-see, because some (rain) might be around the corner, can really suppress timely responses," says Mike Hayes, director of the National Drought Mitigation Center.
Population Growth & Water Use in ACF Basin Population growth – 1990-1999 (counties in grey have lost population) Total water use/consumptive & non-consumptive: 1995
What can we learn from Colorado and ACF compacts? • Compacts need good scientific information– neither compact has fully embraced accurate information abut water availability. • Both failed to adequately embrace the reality of drought and low-flow. • There is a tendency for negotiators to focus on allocation FIRST, worry about availability 2nd. • It’s easier to allocate when you think you have lots of water! • Multi-purpose planning is needed – compacts succeed or fail depending on how they embrace regional needs (e.g., in-stream flow, urban supply, irrigation, pollution). • CRC better at this than the ACF. • Both compacts do a better job of listening to governments than to non-governmental groups (e.g., environmental activists).