If a Purple Line is built, Montgomery County would spend $57.6 million to link the light-rail line with Metrorail’s Bethesda station and another $95.8 million to rebuild a popular running and cycling trail between Bethesda and Silver Spring, under legislation approved Tuesday.

The money was already in the county’s six-year capital budget but required separate legislation because of a county mandate for certain construction projects costing more than $13 million.

County officials said the money will not be spent unless the Maryland Transit Administration builds a 16-mile Purple Line between Bethesda and New Carrollton. The state would use county money to build both the Metrorail connection and trail as part of the larger Purple Line project, county officials said.

Under the legislation, elevators on Elm Street, west of Wisconsin Avenue, would connect the western terminus of a street-level Purple Line with the southern entrance of Metro’s underground Red Line station in downtown Bethesda.

(Interactive graphic: Mapping the proposed Purple Line)

The existing three-mile Georgetown Branch trail between Bethesda and Silver Spring would be rebuilt alongside light-rail train tracks and would be extended about another mile into downtown Silver Spring. That proposal has been one of the most controversial aspects of the state’s plan to link Montgomery and Prince George’s counties via light-rail trains.

Trail advocates have said completing the trail as an extension of the Capital Crescent Trail would provide a critical missing link in the Washington region’s trail network. Critics, including seven Montgomery residents who testified before the County Council on Tuesday, said the rail line’s construction would destroy the wooded trail by cutting 20 acres of trees, be unsafe for local high school students, and bring unhealthy noise levels to neighboring homes.

The Purple Line, with an estimated cost of $2.37 billion, has been recommended for $900 million in federal funding, but no funding agreement has been finalized. The line, which state officials have said they hope to open in 2020, would run two-car trains primarily along local streets and would connect Maryland’s spokes of the Metrorail system with Amtrak and MARC commuter rail stations.

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