Projects & Facilities
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of the Interior
The Robert B. Griffith Water Project (formerly Southern Nevada Water Project) was constructed as a single-purpose project capable of supplying 299,000 acre-feet of supplemental municipal and industrial water annually from Lake Mead to the service area of Las Vegas, North Las Vegas, Henderson, Boulder City, and Nellis Air Force Base in southern Nevada. The project was constructed in two stages. The first stage became operational in November 1971, and was capable of providing 132,200 acre-feet of Lake Mead water annually to the project service area. Construction of the second stage of the project was initiated in 1977 and completed in 1983.
In the early 1990's, the project was incorporated into the Southern Nevada Water System, which is managed by the Southern Nevada Water Authority (SNWA), a political subdivision of the State of Nevada. Also included in the Southern Nevada Water System is the Treatment and Transmission Facility (TTF), which is being constructed by the Southern Nevada Water Authority. The Colorado River Commission of Nevada approved development of this independent water treatment and delivery system in 1994. The SNWA TTF will join with and supplement the capabilities of the Griffith Project, and provide Nevada full access to its 300,000 acre-foot Colorado River water entitlement.
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When the project was being planned, the decision was made to construct it in stages. This provided flexibility in the timing of future installations, and allowed for deviations from the projected future growth rates of population and industry. This plan proved valuable, since it was impossible to foresee the dramatic population increase of the Vegas Valley in the 1960's, 1990's and early 2000's.
The first stage is comprised of a main aqueduct, a 3.78 mile tunnel through the River Mountains, eight pumping plants, and 31.4 miles of pipeline. This stage has a peaking capacity of 26.7 million cubic feet of potable water per day.
The second stage enlarged the first stage system by expanding some of the existing facilities. New features included five pumping plants, the second barrel to the main aqueduct, and about 30 miles of pipeline and laterals with surge tanks, regulating tanks, and other delivery facilities. In conjunction with this stage, the State of Nevada enlarged and modified the Alfred Merritt Smith water treatment facilities to accommodate additional water supplies.
The River Mountains Tunnel was constructed to full capacity in the first stage, and the Saddle Island intake facilities were oversized to accommodate both stages. The aqueduct system has a peaking capability of 53.4 million cubic feet of water per day.
Lake Mead is tapped below the water level on the east side of Saddle Island in Las Vegas Bay, and the water is conveyed through the island to the west through a 13-foot-diameter tunnel which terminates in a pump chamber below Pumping Plant No. 1. The tunnel is generally unlined and about 1,400 feet long. The pumping galley and vertical pump shafts were designed to accommodate the pumping requirements of both stages of the project.
A new lake tap and pumping plant are being constructed by the Southern Nevada Water Authority just south of Pumping Plant No. 1 as part of SNWA's new Treatment and Transmission Facilities.
Constructed by the State of Nevada, the Alfred Merritt Smith Water Treatment Facility currently treats most of the Las Vegas Valley's drinking water. This facility receives Colorado River water through the intake located in Lake Mead. After the water is treated, it is returned to the water transmission system for delivery.
The first stage of the project, in tandem with the first stage of the water treatment facilities and collectively called the Southern Nevada Water System, can deliver up to 132,200 acre-feet of water annually to the project service area. Construction began in 1968 and the first water delivery was made on June 16, 1971.
Recent improvements to the facility increased the plant's reliability and capacity. The facility can treat up to 600 million gallons a day (mgd), and the addition of ozone treatment in 2003 modernized the plant with cutting-edge water treatment technology.
The Main Aqueduct extends 2.97 miles from Pumping Plant No. 1 to River Mountains Tunnel. The first reach consists of 0.60 mile of 120-inch-diameter pipe, has a 585 cubic foot per second (cfs) capacity, and extends from Pumping Plant No. 1 to Alfred Merritt Smith Water Treatment Plant. The second reach is comprised of 2.37 miles of 96-inch-diameter pipe, has a capacity of 300 cfs, and extends from Pumping Plant No. 1A to Pumping Plant No. 2A on to the inlet portal of River Mountain Tunnel.
SNWA has modified this aqueduct to include two outlets to deliver water to a new ozone treatment plant that is being constructed adjacent to the existing Alfred Merritt Smith treatment plant. The modification involved removal of a portion of the original aqueduct as well as a flowmeter structure.
This tunnel was constructed during the first stage to accommodate second stage expansion. It is 3.78 miles long and was excavated through the River Mountains, which lie between Las Vegas Valley and Lake Mead. The concrete-lined tunnel has an inside diameter of 121.5 inches, and a maximum capacity of 608 cfs. The SNWA also constructed a larger tunnel, parallel to the River Mountains Tunnel for further expansion. The River Mountains Tunnel is used to convey raw water from Lake Mead to the River Mountains Water Treatment Facility that SNWA constructed near Henderson, NV.
The River Mountains Facility, which began delivering treated water in October 2002, treats up to 300 million gallons of water per day, and was designed so it can expand to meet Southern Nevada's needs. In the future, the River Mountains facility will be able to treat up to 600 million gallons of water a day. This facility provides additional reliability and capacity to Southern Nevada's municipal water treatment and distribution capabilities.
The Las Vegas Valley Lateral begins at the outlet portal of River Mountains Tunnel. From the tunnel portal to the Henderson Bifurcation, a distance of 0.97 mile, the lateral is a 96-inch-diameter pipe with a 289 cfs capacity. From the Henderson Bifurcation and extending 6.02 miles to the Whitney Bifurcation where the lateral ends and the Whitney and North Las Vegas Laterals begin, the lateral is constructed of 90-inch-diameter pipe with 261 cfs capacity.
This lateral has been modified by the SNWA to connect to the new tunnel through the River Mountains.
The 10-mile-long North Las Vegas Lateral begins at the Whitney Bifurcation and terminates near Nellis Air Force Base. The lateral consists of 1.8 miles of 72-inch-diameter pipe with a capacity of 101 cfs, 3.07 miles of 66-inch-diameter pipe with a capacity of 86 cfs, 1.41 miles of 48-inch-diameter pipe with a capacity of 56 cfs, and 3.75 miles of 24- and 27-inch-diameter pipe with a capacity of 16 cfs at its terminus.
This lateral begins at the Whitney Bifurcation and terminates at a receiving reservoir built by the Las Vegas Valley Water District near the intersection of Flamingo and Pecos Roads. The lateral includes 1.63 miles of 66-inch-diameter continuous steel pipe and 1.65 miles of 66-inch-diameter jointed steel pipe. The capacity is 160 cfs.
This lateral begins at the Sahara Bifurcation on the North Las Vegas Lateral near the end of Sahara Avenue and extends eastward to the Sahara Flow Control Station. The lateral is constructed of 24-inch diameter pipe and has a total length of 0.34 mile. The capacity is 15 cfs.
The Henderson Lateral begins at the bifurcation with the Las Vegas Valley Lateral and terminates at a tank built by the city of Henderson. It is a gravity-flow lateral from its beginning to Pumping Plant No. 3. A pumping plant lifts the water the remaining distance to the terminal tank. The 28 cfs-capacity lateral required 4.53 miles of 36-inch-diameter pipe.
Boulder City Lateral begins at Pumping Plant No. 1A and terminates at the twin 5-million-gallon receiving tanks built by the City of Boulder City. The 36- and 27-inch-diameter pipe delivers 30 cfs and has a total length of 7.48 miles.
Construction of the second stage provided an additional annual delivery capability of 166,800 acre-feet of Colorado River water. Peak delivery capacity is now 53.4 million cubic feet per day. This was accomplished through the addition of five new pumping plants, modifications to four existing pumping plants, a 2.39-mile-long second barrel to the main aqueduct, about 30 miles of new aqueducts and pipelines, and a major expansion of the existing Alfred Merritt Smith water treatment facility. Since the Saddle Island intake facilities and the 3.78-mile tunnel through the River Mountains were sized during construction of the first stage to accommodate flows of the second stage, there was no need for new tunnel works.
The Main Aqueduct runs from Pumping Plant No. 1B to the River Mountains Tunnel inlet portal. The aqueduct consists of two sections. The first section, from Pumping Plant No. 1B, to Pumping Plant No. 2B, consists of 1.35 miles of 96-inch diameter pipe with a design capacity of 306 cfs. The second section, from Pumping Plant No. 2B to the River Mountains Tunnel inlet (Regulating Tank No. 2), consists of 0.82 mile of 96-inch diameter pipe and 0.22 mile of 108-inch diameter pipe with a design capacity of 306 cfs. The River Mountains Tunnel and the Saddle Island Intake Tunnel and Pumping Chamber on Lake Mead were initially constructed at full size and did not have to be enlarged to accommodate the design flows of the second stage.
The Pittman Lateral begins at the outlet portal of River Mountains Tunnel. From the tunnel portal to the Foothill Turnout, the lateral is 102-inch diameter pipe, 0.31 mile long, with a design capacity of 319 cfs. From the Foothill Turnout to the North Lateral Turnout, it is 102-inch diameter pipe, 1.05 miles long, with a design capacity of 310 cfs. From the North Lateral Turnout to the Mesa Lateral Bifurcation, the lateral is 102-inch diameter pipe, 5.21 miles long, with a design capacity of 302 cfs. From the bifurcation to the Hacienda Control Station, the lateral has 3.14 miles of 96- and 90-inch-diameter pipe, and a capacity of 270 cfs. From Hacienda Pumping Plant to the Valley View Regulating Tank, the lateral has 6.45 miles of 90-inch-diameter pipe with a peak capacity of 270 cfs. From the regulating tank to Oakey Turnout, the terminus of Pittman Lateral, the pipe is 84 inches in diameter, 3.63 miles long, with a design capacity of 232 cfs. The Oakey Turnout diverts 150 cubic feet per second into Oakey Forebay.
This lateral has been modified by SNWA to connect to the new tunnel through the River Mountains.
Hacienda Forebay and Pumping Plant is located at the intersection of Annie Oakley Drive and Hacienda Avenue. The pumps lift water from a forebay to a regulating tank near the intersection of Tropicana Avenue and Valley View Boulevard. The plant has six pumping units of 43.75 cfs capacity each, for a peak capacity of 250 cfs and a head of 365 feet. An extra pumping unit was installed as a standby unit and will is used when a peak flow of 270 cfs is needed.
The Fayle Lateral runs from Valley View Regulating Tank to Fayle Reservoir. The lateral has 0.34 mile of 72-inch diameter pipe placed parallel to Pittman Lateral, and a peak capacity of 140 cfs.
The Twin Lakes Lateral begins where Pittman Lateral ends at the Oakey Turnout. From Oakey Turnout to Charleston Heights Turnout, the lateral is 48-inch diameter pipe, 1.24 miles long, and has a design capacity of 82 cfs. From Charleston Heights to Twin Lakes Pumping Plant and Forebay, the lateral is 33- and 36-inch diameter pipe, 2.32 miles long, with a design capacity of 42 cfs. From Twin Lakes to Carlton Square Reservoir, the terminus of Twin Lakes Lateral, the lateral has 1.80 miles of 42-inch diameter pipe with a design capacity of 32 cfs.
Foothill Lateral begins at the Foothill Turnout on Pittman Lateral. From the turnout to the Foothill Forebay, where the lateral ends, it is 21-inch diameter pipe, 0.20 mile long, with a design capacity of 12 cfs.
The North Lateral begins at the North Lateral Turnout on Pittman Lateral. From the turnout to a reservoir built by the city of Henderson, the lateral is 24-inch diameter concrete pipe, 0.58 mile long, with a design capacity of 11 cfs.
Mesa Lateral begins at the Mesa Lateral Bifurcation on Pittman Lateral. From the bifurcation to a receiving tank built by the city of Henderson, the lateral is 42-inch diameter pipe, 2.17 miles long, with a design capacity of 46 cfs.
Charleston Heights Lateral begins at the Charleston Heights Bifurcation on Twin Lakes Lateral. From the bifurcation to the Las Vegas Valley Water District's tanks, the lateral is 42-inch diameter pipe, 0.14 mile long, with a design capacity of 40 cfs.
Robinson Lateral begins at Twin Lakes Pumping Plant and Forebay. From the pumping plant to the end point of the lateral at a water tank owned and operated by the city of North Las Vegas, the lateral is 24-inch diameter pipe, 1.52 miles long, with a design capacity of 10 cfs.
Beginning at Pumping Plant No. 7B, the Colorado Street Lateral extends 0.52 mile to Boulder City`s west tank. The lateral is 18-, 21-, and 27-inch-diameter pipe and has a capacity of 7.5 cfs.
The Hemenway Lateral is located on the Boulder City Lateral about 2,500 feet before it reaches Surge Tank No. 5. The lateral is 8- and 12-inch-diameter pipe, with a capacity of 2.5 cfs.
RECENT CONSTRUCTION - River Mountains Treatment Facility
The River Mountains Treatment Facility began delivering treated water in October 2002. Designed so it can expand to meet Southern Nevada's growing needs, it presently treats up to 300 million gallons of water per day, but will be able to treat up to 600 million gallons of water a day. It uses uses both ozone and chlorine in its disinfection process.
The federal government transferred ownership of the Robert B. Griffith Water Project to the Southern Nevada Water Authority on July 3, 2001. The transfer, which cost $121.2 million, gave the Water Authority control over the facilities it operates and relieved the federal government of liabilities associated with ownership.
The first caravan of pioneers stopped in the Las Vegas area in about 1832. In 1905, the San Pedro-Los Angeles Railroads (later the Southern Pacific Railroad) were linked, and Las Vegas was established as a division point. The Las Vegas Land and Water Co. was formed on May 2, 1905, to supply water to the locomotives and domestic water to the new town that was established by the railroad company. In 1931, thousands of workers moved into the area for the building of Hoover Dam. Boulder City was constructed as part of the Boulder Canyon Project to house the workers who were building the dam, along with their families.
By 1944, Las Vegas and the surrounding area were running out of groundwater. In 1947, the Nevada State Legislature passed a bill authorizing the establishment of the Las Vegas Valley Water District to purchase the Land and Water Co. and to bring water into Las Vegas Valley via pipeline from Lake Mead. The ownership of the company`s facilities was transferred to the district in 1954.
On August 25, 1967, a contract was executed between the United States and the Colorado River Commission of Nevada for delivery of water and construction of project works. In 1969, the contract with the Government was revised to include the Las Vegas Valley Water District as a participant in the Southern Nevada Water Project.
Under the contract, the State committed 132,200 acre-feet of its allocated 300,000 acre-feet of Colorado River water to municipal and industrial use in Clark County, Nevada.
In November 1967, Congress approved the first funding of the Southern Nevada Water Project, and work began in 1968. The Alfred Merritt Smith Water Treatment Plant was completed in 1970 and the first stage of the project was completed in 1971.
Forecasts made in the late 1960's and early 1970's of the water needs in the Las Vegas Valley indicated that, with the existing water supply systems, the first stage of the Southern Nevada Water Project would be able to meet the water requirements of the area until 1990. However, the economy of the area had entered a new era of rapid growth, which placed an unanticipated load on the system during the first four years of operation. New water demand projections indicated the capacity of the project's first stage would be used or exceeded in the early 1980's, resulting in the initiation of construction of the project's second stage in 1977. This stage, completed in 1983, is capable of delivering 166,800 acre-feet of Colorado River water annually.
The delivery portion of the project, including a pipeline and pumping stations, built by the Bureau of Reclamation was called the Southern Nevada Water Project, until it was renamed the Robert B. Griffith Water Project in 1982. Meanwhile, the state built and paid for the Alfred Merritt Smith Water Treatment Facility. These two projects comprise the Southern Nevada Water System.
Construction began in 1968, and the system began operations in 1971. A second construction phase began in 1977 and was completed in the early 1980's. Additional capital improvements were made in the 1990's, increasing the treatment and delivery of water up to 600 million gallons each day.
The Bureau of Reclamation made appraisal field inspections of areas in Clark County, Nevada, that were considered to be irrigable with water from the Colorado River in 1932 and 1944. The findings of the 1944 studies were included in a March 1946 report as the Las Vegas Pumping Project. A report on the preliminary investigations, March 1955, presented information on water supply and future requirements for the Las Vegas Valley area. From 1953-1956, cooperative land classification and soil surveys were made of the Las Vegas Valley and Eldorado Valley subareas. The report covering these surveys was issued in February 1967. The potential of providing municipal, industrial, and agricultural water for developing Eldorado Valley, near Boulder City, was described in an October 1959 report on reconnaissance investigations. The August 1963 feasibility report on the Southern Nevada Water Project, and the 1965 supplement to the report, recommended authorization and construction of the project. The report and supplement were printed as House Document No. 177, 89th Congress, 1st session. Results of the advance planning studies for the first stage of the project were in the definite plan report on "Southern Nevada Water Project (First Stage)" in August 1967. The definite plan report on the second stage was prepared in October 1976 and the final environmental statement on the second stage was issued June 6, 1977.
On October 22, 1965, the President signed Public Law 89-292, authorizing construction, operation, and maintenance of the project. Public Law 89-510, July 19, 1966, clarified water rights and amended Public Law 89-292.
On December 22, 1982, the name of the project was changed to the Robert B. Griffith Water Project by Public Law 97-381.
Construction of the first stage started with the award of a contract for the construction of the River Mountain Tunnel and Outlet Portal on March 26, 1968. The first water deliveries were made to the Las Vegas Valley District on June 16, 1971, and the first stage became operational on November 1 that year. Construction of the project's second stage began in June 1977. Initial water delivery from this stage occurred on March 19, 1982, and all construction was completed in 1983. Additional capital improvements were made in the 1990's.
The project provides the Las Vegas Valley with more than 90 percent of its annual water supply, serving Colorado River water to more than two million people in the Las Vegas Valley and Boulder City areas. It also provides potable water to the 250,000 visitors who occupy Las Vegas Strip resorts on an average day.