Project details - Boulder Canyon Project - All-American Canal System

Mean Annual	74.4 ?F
Daily Maximum - 07/28/1995	124 ?F
Daily Minimum - 02/18/1995	5 ?F
Yuma, Arizona 1948-1996
Growing Season	365 days
Elevation of irrigable area	-229 to 75 ft

Colorado River

Drainage area at Imperial Dam	mi2
Annual discharge:
Maximum	acre-ft
Minimum	acre-ft
Average	acre-ft

Streamflows

Colorado River below Imperial Dam, California-Arizona (USGS)

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Project Water Quality

Facilities in Operation

Facilities in Operation

Storage Dams	1
Diversion Dams	1
Canals	203 mi
Laterals	463 mi
Coachella Distribution System	495 mi
Imperial Distribution System	1,474 mi
Pumping Plants	16
Drains
Coachella	16.0 mi
Imperial	1,454.5 mi
Powerplants	4

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Storage Facilities

Hoover Dam

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Diversion Facilities

Imperial Dam

Type	Concrete slab and buttress, ogee weir
Location	Colorado River, 18 miles northeast of Yuma, Arizona
Construction period	1936-1938
Dimensions:
Structure height, overflow section	31 ft
Structural Height, nonoverflow section	85 ft
Hydraulic height	23 ft
Base width of weir	76 ft
Crest Width, nonoverflow section	12 ft
Crest Length, overflow section	1,198 ft
Total Length	3,475 ft
Crest Elevation, overflow section	181.0 ft
Crest Elevation, nonoverflow section	196.3 ft
Volume	196,800 yd3
Spillway	Overflow ogee weir
Overflow capacity at 191.0 ft	180,000 cfs

All-American Canal Headworks

Type	Concrete-lined channel 360 feet wide, controlled by four 75- by 23-ft roller gates. Downstream from the gates, four channels direct water into the desilting basins
Location	Adjacent to California abutment
Construction period
Diversion capacity	15,155 cfs
Sluiceway	Concrete-lined channel, bottom width ranges from 241.5 to 216 feet, controlled by twelve 16- by 8-feet radial gates
Capacity:
At elevation 191.0 ft	42,500 cfs
At elevation 179.5 ft	31,000 cfs

Gila Gravity Main Canal Headworks

Type	Concrete-lined channel controlled by three 35.67- by 14.5-ft radial gates
Location	Adjacent to Arizona abutment
Construction period
Diversion Capacity	2,200 cfs
Roadway	Service bridge consists of a concrete deck carried by 4 plate girder spans 91.5 ft long overall and 76 ft between bearings. The single lane has design load of 20 tons. Maintenance bridge consists of eight 37 ft spans supported on concrete pile bents with concrete caps

All-American Canal Desilting Works

Adjacent to the All-American Canal Headworks, three desilting basins are laid off at an angle of 60 degrees from the intake canal and each is divided into half by a long V-shaped influent channel. The dimensions of each half-basin are 269 ft wide by 769 ft long. Each basin is designed to handle a maximum of 2,000 cfs and each pair of basins is fed by an influent channel. Twelve rotating scraper mechanisms are installed in each half-basin to collect and remove the silt that settles out of the water. The water depth is 12.5 ft. The velocity of water is about 0.25 ft/s. Silt deposited in the basins during the passage of water from influent to effluent channels is removed by means of 72 rotary-type scrapers, each 125 ft in diameter, which force the deposited silt into collecting trenches from which it is flushed into a system of sludge disposal pipes, to the sluiceway channel, and then into the Laguna Settling Basin about 2 mi south of Imperial Dam.

The designed desilting capacity at a canal discharge rate of 12,000 cfs equals 70,000 tons per day; 600,000 to 700,000 yd? of sediment are removed annually.

Gila Canal Desilting Works, Gila Gravity Main Canal

The Gila Canal Headworks were constructed at the Arizona end of Imperial Dam. Downstream from this structure, the desilting works for the Gila Gravity Main Canal were installed. The Gila desilting works consists of one concrete-lined basin with space allowed for the construction of two additional basins. This basin was designed for desilting a maximum flow of 2,200 cfs. It is formed by two levees extending perpendicularly to the axis of Imperial Dam on either side of the third gate structure of the Gila Canal Headworks. The basin is roughly 1,175 ft long, including inlet and outlet transitions. The bottom width ranges from about 115 to 104 ft between the transitions. The average depth of water is about 20 ft, and the average velocity is 0.66 ft/s. Flow from The basin is controlled by two sets of eight 7- by 16-ft fixed wheel gates, one set located above the other. The upper eight are for diverting and the lower eight are used during sluicing operations. The sluicing water is returned to the river by a curved channel 1,800 ft long. The Gila Canal desilting works are capable of removing about 8,130 tons per day.

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Carriage Facilities

All-American Canal - Imperial Division

Location	From Imperial Dam west-southwest about 80 miles to the vicinity of Calexico, California
Construction period	1934-1940
Length	80 mi
Diversion capacity	15,155 cfs
Typical section (earth lined):
Bottom width	160 ft
Side slopes	1.75:1
Water depth	21 ft
Lining:	Compacted clay on bottom; loose clay on sides
Bottom thickness	4 in
Side thickness	6 in

New River Siphon - All-American Canal

Location	At the New River, about 2 miles west of Calexico, California
Construction period	1937-1938
Description	Twin barrels welded 0.5-in thick, plate-steel pipes on reinforced concrete piers resting on reinforced concrete pile footings
Length of siphon	374 ft
Diameter each barrel	15.5 ft
Capacity	2,700 cfs
Distribution system:1
Main canals	235.5 mi
Open channel	224.1 mi
Concrete lined	11.4 mi
Lateral canals	1,472.1 mi
Open channel	686.6 mi
Concrete lined	776.7 mi
Pipeline	8.8 mi

1 Constructed and operated by the Imperial Irrigation District

Coachella Canal

Location	From Drop No. 1 on All-American Canal, about 18 miles west of Yuma, Arizona, northwest to vicinity of Indio, California
Construction period	1938-1948
Length	123 mi
Diversion capacity	2,500 cfs
Typical section, earth lined:
Bottom width	40-60 ft
Side slopes	2:1
Water depth	10.3 ft
Lining, clay-blanket	12 in
Typical section, concrete lined:
Bottom width	12 ft
Side slopes	1.5 :1
Water depth	10.8 ft
Lining thickness	3.5 in

Coachella Canal Replacement

Distribution system, underground concrete pipe. Pipe sizes range from 1 to 7 feet in diameter

495 mi

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Pumping Plants

Designation	Number of units	Total capacity, cfs	Total dynamic head, feet	Total horsepower
Major Pumping Plants
Pumping Plant L-1	3	16.8	45	120
Pumping Plant L-2	4	39	37	230
Pumping Plant L-3
High Lift	3	12.6	32.5
Low Lift	1	3	17
Pumping Plant L-4	4	46.8	40	300
Pumping Plant L-5	6	36.9	35-37	160
High Lift	3	15.6	37
Low Lift	3	15	35
Pumping Plant L-6	2	9	37	50
Coachella 0-1	2	21	38	120
Coachella 0-2	2	6	42	40
Relift Pumping Plants
Lateral 113.0	1	3	11
Lateral 114.3	1	3	9
Lateral 114.8	1	3	7
Lateral 115.3	1	3	10.5
Wistaria No. 1	2	20	7.8
Wistaria No. 2	2	20	3.04
Woodbine Canal	1	9	2.74
West Side	1	5	2.75

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Power Facilities

The Imperial Irrigation District has constructed powerplants at Pilot Knot Check and Wasteway, and at Drop Nos. 2, 3 and 4 of the All-American Canal. Installed capacities of these plants are:

Pilot Knob	33.0 MW
Drop No. 2	10.0 MW
Drop No. 3	9.8 MW
Drop No. 4	19.6 MW

The district also operates the 189.1 MW steam plant at El Centro. The 75 MW axis steam plant at Yucca is operated by the Arizona Public Service Company, but the Imperial Irrigation District has rights to 25 MW of the plant's production. Imperial's electrical distribution system interties with the Department of Energy's Parker-Davis system.

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Last updated: Feb 01, 2012