A Montgomery County Council member abandoned his push Thursday for single-tracking on the Purple Line after a new study found it would slow trains, reduce ridership and save few trees.

Councilman Roger Berliner, D-Bethesda, wanted a single track between Bethesda and Columbia Country Club in Chevy Chase, saying it could salvage trees along the planned, 16-mile light rail line. But he relented Thursday, effectively killing prospects for any single-track segments on the transit system that would connect the Bethesda and New Carrollton Metro stations.

"I had hoped to be able to convince you that single-tracking would not compromise the integrity of the system," he said during a council committee meeting. "I grudgingly will come to the same conclusion [as those against single-tracking]."

The study by the Maryland Transit Authority found that implementing a single track for the 3,500-foot stretch would add at least a minute to trips and reduce passenger loads by roughly 20 percent. And because of enhancements needed for an adjacent walking and biking trail, trees would be eliminated anyway.

A mishmash of federal, state and local money is expected to fund the $1.6 billion project, and elements of the plan were further crystallized Thursday.

Replacing the Capital Crescent Trail, running adjacent to the Purple Line, would cost at least $65 million rather than the $25 million originally projected, according to the MTA. The new price tag is the result of regrouping costs previously tied to rail expenses, transportation officials say.

The funding for the trail is still not clear, but Councilman George Leventhal, D-at large, said, "The trail is historically a county project."

Montgomery County Public Schools officials also pushed a plan that would combine the Talbot Avenue Bridge with the Georgetown Branch Trail near Rosemary Hills Elementary School in Silver Spring. However, council members largely resisted the plan, as it would likely displace homeowners near the school.

The Purple Line has been in the works for two decades, but trains could start running in 2016.