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Phoenix Area Office

Native Aquatic Species of the Gila River Basin
in Arizona and New Mexico

Biological Opinions

Biological Opinion on the Transportation and Delivery of Central Arizona Project Water to the Gila River Basin in Arizona and New Mexico

Central Arizona Project Waddell Dam and Lake Pleasant The Central Arizona Project was constructed to provide a long term, renewable water source for municipal, industrial, and non-Indian agricultural users in Arizona. An average of 1.5 million acre-feet of Arizona's allocation of 2.8 million acre-feet of Colorado River water is delivered annually through the CAP aqueduct system (MAP HERE). The water is diverted from the Colorado River at Lake Havasu and is conveyed across the state in a series of siphons, tunnels and large open aqueducts: Hayden Rhodes, Fannin-McFarland, and Tucson. In 1993, PXAO completed construction of New Waddell Dam which enlarged the storage capacity of Lake Pleasant, an existing reservoir on the Agua Fria River north of Phoenix. Water is pumped from the CAP canal during the winter months for storage; in the warmer months water is released to meet increased demand and simultaneously generates electricity.

The CAP system was declared substantially complete on Septemeber 30, 1993.

Ashurst-Hayden  Diversion Dam The waters conveyed by the CAP can connect both directly, via existing canals and reservoirs, or indirectly, via return flows, to the rivers of the Gila River basin. This connection opens potential conduits for the transfer of non-native species of fish to the lower Gila River basin tributaries and to the middle and upper Gila River basin above Ashurst-Hayden Dam. The Hassayampa, Agua Fria, Salt and Verde Rivers, as tributaries of the Gila, could also enable any fish species introduced into their waters from the CAP to reach the Gila River and eventually move upstream to the base of Ashurst-Hayden. Ashurst-Hayden Dam is not an effective fish barrier for several reasons, both structural and operational, and any fish species that reach the base of the dam would have the opportunity to move beyond it to the middle Gila and San Pedro Rivers. The presence of the CAP connection creates a perennial waterway from the Colorado River to the major streams of the Gila River Basin, potentially connecting rivers and canal systems that otherwise would be more isolated by dams and intermittent stream reaches.

Gila River In the early 1990s The Phoenix Area Office of the Bureau of Reclamation entered into formal Section 7 consultation with the Fish and Wildlife Service (FWS) over the issue of transportation and delivery of Central Arizona Project water to the Gila River Basin (Hassayampa, Agua Fria, Salt, Verde, San Pedro, Santa Cruz, middle and upper Gila Rivers, and associated tributaries) in Arizona and New Mexico. Federal agencies must consult with FWS whenever it is determined that a project that is being built or funded by the agency may affect a species listed under the Endangered Species Act. In its Biological Opinion (April 20, 1994), FWS found that these deliveries would jeopardize the continued existence of the Spikedace (Meda fulgida), Loach Minnow (Tiaroga cobitis), Gila Topminnow (Poeciliopsis occidentalis), and Razorback Sucker (Xyrauchen texanus) and would adversely modify the critical habitat of the spikedace, loach minnow, and razorback sucker.

In order to remove jeopardy to these species the FWS proposed a reasonable and prudent alternative containing five primary elements:
  1. Construction and operation of upstream barriers to fish movement from the CAP aqueduct into native fish habitats
  1. Monitoring of nonnative fish
  1. Transfer of funding to FWS for the recovery and protection of listed and candidate Gila basin fishes as mitigation for adverse project effects which cannot feasibly be alleviated below the jeopardy threshold
  1. Transfer of funding to FWS for management against nonnaitve fish and research to support that management
  1. Implementation of an information and education program regarding nonnative aquatic fishes.
In a 2001 reconsultation with FWS, these reasonable and prudent alternatives were voluntarily made conservation measures (part of the CAP project) by Reclamation. More recently a 2008 resconsultation with FWS expanded the list of conservation measures to include the following:
  1. Reclamation will construct physical drop structures that act as barriers to upstream fish movement at 12 locations (see Fish Barrier Page for specifics). Reclamation or their designee will maintain the barriers throughout the life of the project.
  1. Reclamation or their designee will maintain and operate the existing electrical barriers on the Florence-Casa Grande Canal near China Wash and Salt River Project on the Arizona and South Canals throughout the life of the project.
  1. Reclamation will implement a baseline study and long-term monitoring of the presence and distribution of non-native fish in the following areas:
    • CAP aqueducts
    • SRP canals
    • Florence-Casa Grande Canal
    • Gila River between Coolidge Dam and Ashurst-Hayden Diversion Dam
    • Salt River between Stewart Mountain Dam and Granite Reef Dam
    • San Pedro River downstream of the US / Mexico border
    • Cienega Creek Preserve
  1. Reclamation will transfer $275,000 annually for 21 years in addition to 9 years of funding that has already been provided to FWS for conservation actions (recovery and protection) for the spikedace, loach minnow, Gila topminnow, razorback sucker, or other Gila Basin listed or candidate fish species. Expenditure of these funds shall be jointly agreed upon by FWS and Reclamation in consultation with the Arizona Game and Fish Department and the New Mexico Department of Game and Fish.
  1. Reclamation shall transfer $275,000 annually for 21 years (in addition to 9 years of funding that has already been provided) to FWS for research on, and control of non-native aquatic species. Expenditure of these funds shall be jointly agreed upon by the Service and Reclamation in consultation with the Arizona Game and Fish Department and the New Mexico Department of Game and Fish.
  1. Reclamation will develop and implement an information and education program directed to conservation of native fishes and their habitat. Emphasis is be placed on problems caused by bait-bucket transfer, dumping of pet aquarium fish, and other forms of transport by the public.
  1. Reclamation will provide $100,000 to FWS toward development of a Chiricauha leopard frog rearing facility, or other conservation actions.

Reports:

April, 1994: Biological Opinion on the Transportation and Delivery of Central Arizona Project Water to the Gila River Basin (Hassayampa, Agua Fria, Salt, Verde, San Pedro, Middle and Upper Gila Rivers, and Associated Tributaries) in Arizona and New Mexico

April, 2001: Revised Biological Opinion on Transportation and Delivery of Central Arizona Project Water to the Gila River Basin (Hassayampa, Agua Fria, Salt, Verde, San Pedro, Middle and Upper Gila Rivers and Associated Tributaries) in Arizona and New Mexico and its Potential to Introduce and Spread Nonnative Aquatic Species

May, 2008: Reinitiated Biological Opinion on Transportation and Delivery of Central Arizona Project Water to the Gila River Basin in Arizona and New Mexico and its Potential to Introduce and Spread Nonindigenous Aquatic Species



Last Reviewed:
August 30, 2010

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Joseph J. Billerbeck - jbillerbeck@usbr.gov