PHOENIX — U.S. Department of Transportation’s Federal Transit Administration announced a $100 million grant Tuesday for a Phoenix light rail extension, money that will go away if voters pull the plug on the project next month.

The 5.5-mile South Central Avenue extension from the existing downtown tracks to Baseline Road has become a contentious issue, with opponents calling it a waste of money and saying it will negatively impact the neighborhood.

In February, the City Council approved an initiative to put the project up for a vote, which will be held Aug. 27.

The city is responsible for under a quarter of the approximately $1 billion price tag, with its $220 million portion covered as part of a long-term transportation tax approved by voters in 2015.

Just announced: $300M in FY19 allocations to projects in AZ, CA & WA through FTA’s #CIG Program: $100M each for S. Central Light Rail Extension in Phoenix; Westside Subway Section 3 in LA & and Seattle's Federal Way light rail https://t.co/SCvhJaykB5 pic.twitter.com/YnfUxTBucl — Federal Transit Admn (@FTA_DOT) July 9, 2019

Federal and regional funds are earmarked for the remainder the cost, but that money will be available only for the approved Central Avenue plan.

Light rail supporters, including Mayor Kate Gallego, say the project will spur economic development in the South Phoenix area.

“Today’s announcement is also an important reminder of the federal dollars that our city would lose out on should Proposition 105 pass in the city’s August election, effectively ending light rail in Phoenix,” Gallego said in statement Tuesday.

“Ensuring that federal dollars go to important projects such as the light rail expansion means that our city tax dollars can fund priorities such as public safety and additional road improvements.”

The approved plan for the nine-station extension would reduce Central Avenue from four lanes to two lanes, a major concern for those who want to see the project killed.

In April, project gained approval to move into its next phase, which made Valley Metro eligible to use up to $530 million from an FTA grant program.

Valley Metro, the Phoenix area’s public transportation agency, said that funding would let the agency continue with preconstruction activities and procurement.

Preconstruction work was scheduled to begin this summer, and construction on the line was expected to begin in spring 2020. The goal was to begin service in 2023.

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