Trump signs law clearing path for Southern Nevada water pipeline

Sen. Catherine Cortez Masto, D. Nev., speaks during the third annual water summit hosted by Congresswoman Susie Lee, D-Nev., at the Las Vegas Springs Preserve Thursday, Aug. 28, 2025. Photo by: Steve Marcus

The Southern Nevada Water Authority has won federal authorization to build a 40-mile water pipeline beneath a Clark County conservation area, a project lawmakers say will safeguard the region’s water supply for generations. 

The White House said President Donald Trump signed H.R. 972, the Sloan Canyon Conservation and Lateral Pipeline Act, into law Tuesday.

The law directs the Department of the Interior to grant the Southern Nevada Water Authority rights-of-way for the construction and operation of a 40-mile water pipeline beneath the Sloan Canyon National Conservation Area. The pipeline would have the capacity to carry 375 million gallons of water per day to Henderson and the southern Las Vegas Valley.

The project, known as the Horizon Lateral pipeline, addresses what lawmakers have described as a dangerous gap in Southern Nevada’s water infrastructure. Currently, the water authority operates one large pipeline — the South Valley Lateral — that serves approximately 40 percent of the residents and businesses in the Las Vegas Valley, including the entire city of Henderson.

The new underground route is expected to save residents in the region $200 million and ensure water delivery redundancy in the case of emergencies.

The law also expands the Sloan Canyon National Conservation Area in Clark County by nearly 9,300 acres. The conservation area, designated by Congress in November 2002, includes the Sloan Petroglyph Site, which is home to more than 300 rock art panels containing 1,700 petroglyphs created by Indigenous cultures dating thousands of years.

Without congressional approval, rights-of-way may not be located through or under areas designated as wilderness, and construction of the pipeline may not permanently adversely affect surface resources within the conservation area.

U.S. Rep. Dina Titus, D-Nev., who introduced the House version of the bill in February 2025, hailed the signing as a landmark for the region.

“Southern Nevada is the epicenter of the climate crisis with rising temperatures and dwindling water resources,” Titus said in a statement Wednesday. “Our precious water supply must be protected. The Horizon Lateral pipeline strikes an important balance.”

U.S. Sen. Catherine Cortez Masto, D-Nev., who led the legislation in the Senate, said the stakes could not be higher for Las Vegas Valley water consumers.

“That’s a dangerous situation in which one system failure could cut off the water supply for close to 40 percent of Las Vegas residents and businesses,” Cortez Masto said in a statement. “This law will increase the reliability of Southern Nevada’s water supply for generations to come.”

The bill passed the Senate without amendment by unanimous consent. The House had passed the bill Dec. 15, 2025.

Some critics have said the construction of the pipeline could encourage further urban sprawl in the valley, especially if passed in coordination with the Southern Nevada Economic Development and Conservation Act, which would make about 25,000 acres of public land south of Las Vegas available for development.

Southern Nevada is one of seven states that rely on the Colorado River system. In recent years, Lake Mead and Lake Powell have experienced historically low levels due to prolonged drought and reduced runoff.

The Congressional Budget Office estimated the law would have a negligible effect on net direct spending. The rights of way would be provided at no cost to the water authority, and the public land added to the conservation area and used for the rights of way is currently withdrawn from mineral leasing, so the federal government would not forgo any receipts from those activities.