All-American Canal Lining Project

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Authorized and constructed pursuant to the Boulder Canyon Project Act, the All-American Canal is operated and maintained by IID under a contract with the United States Bureau of Reclamation. The 2009 completion of the All-American Canal Lining Project resulted in the concrete lining of 23 miles of the unlined AAC.

The project consisted of the planning; environmental compliance and permitting activities; preparation of schedules, plans, specifications and cost estimates; administration; design; construction; and implementation of environmental mitigation measures required to construct a 23-mile concrete lined canal parallel to the existing earthen canal, from one mile west of Pilot Knob to Drop 3. The new concrete lined section of the AAC will conserve 67,700 acre-feet per year of Colorado River water that was previously lost to seepage.

History
In the late 1990's the USBR concluded that an estimated 70,000 acre-feet per year of water is lost due to seepage along a 23-mile section of the All-American Canal running through the sand dunes from Pilot Knob to Drop 3. Until recently, the cost associated with seepage recovery was considered prohibitive.

In 1998, Public Law 100-675 was enacted. It authorizes the secretary of the interior to line the All-American Canal or to recover seepage from it.

In August 1998, the state legislation was approved and $235 million was appropriated for a water project that ensures continued flows from the Colorado River. Of the appropriation, $200 million was used to concrete line part of the All-American Canal and its Coachella branch. The remaining $35 million will increase underground water storage along the Colorado River aqueduct.

The interior department notified IID in November 1999 that the 1994 Environmental Impact Statement/Environmental Impact Report and Record of Decision on the lining of the canal continued to meet the requirements of the National Environmental Policy Act and the California Environmental Quality Act and was valid until construction was completed in 2009.

Enviromental Mitigation
Throughout the AACLP, the IID has worked with the U.S. Bureau of Reclamation to minimize impacts to the environment from construction activities. IID conducted detailed studies to identify sensitive plants, wildlife and habitat that could be affected. IID implemented an environmental mitigation-monitoring program to ensure environmental protection during construction. The mitigation monitoring program included:

  • Avoiding and minimizing impacts to sensitive biological resources
  • Preserving offsite mitigation lands
  • Compensating for impacts by restoring affected habitat

Environmental studies conducted along the AACLP identified sensitive cultural sites, and sensitive plant and wildlife species that may be impacted by the work activities. The AACLP mitigation program included the restoration of desert dune plant species, flat-tailed horned lizard compensation, a wetland enhancement between Drops 3 and 4, large mammal tracking, canal fishery mitigation compensation, razorback sucker retrieval, and treatment for cultural resources.

Wetland Enhancement Project – The Chanan Remington Memorial Wetland
The AACLP has the potential to cause the loss of hundreds of acres of seepage wetlands as well as 34 acres of canal bank vegetation between Drops 2 and 3. IID has committed to expand/enhance the seepage wetlands complex between Drops 3 and 4 as compensation for the anticipated loss.

The habitat is characterized by several community types, including Freshwater Marsh, riparian woodlands, and scrub communities. Modifications to the physical characteristics of the canal (location and lining) may significantly impact groundwater elevations and water quality. Changing the groundwater characteristics may consequently affect existing and created/enhanced wetlands. Lining of the canal would reduce percolation of surface water. The resulting reduction in seepage and groundwater recharge and availability may impact the surrounding wetland habitat by reducing the water level and potentially eliminating wetlands at higher surface elevations. In addition, reduction in groundwater recharge with surface water from the canal may also influence water quality. Mitigation for potential loss of wetlands is one component of the AACLP and involves the creation and enhancement of 44 acres of wetland and riparian habitat within the approximately 2,000-acre wetland complex between Drops 3 and 4. This expanded/enhanced acreage will include 43 acres of honey mesquite and/or conttonwood willow, and one acre of marsh vegetation. 

Download Construction Monthly Progress Report
July 2006 [PDF]
August 2006 [PDF]
September 2006 [PDF]
June 2007 [PDF]
July 2007 [PDF]
August 2007 [PDF]
September 2007 [PDF]
October 2007 [PDF]
November 2007 [PDF]
December 2007 [PDF]
January 2008 [PDF]
February 2008 [PDF]
March 2008 [PDF]
April 2008 [PDF]
May 2008 [PDF]
June 2008 [PDF]
July 2008 [PDF]
August 2008 [PDF]
September 2008 [PDF]
October 2008 [PDF]
November 2008 [PDF]
December 2008 [PDF]
January 2009 [PDF]

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