Purple Line construction work on Elm Street in downtown Bethesda, shown here in February, has disrupted some nearby businesses. (Michael S. Williamson/The Washington Post)

Some of the businesses along Maryland’s Purple Line will get help to survive the massive light-rail construction project that they fear will imperil their livelihoods as customers search for parking and navigate around bulldozers and orange barrels.

The Prince George’s County Council on Thursday allotted $200,000 to businesses along the Purple Line corridor, and the Montgomery County Council earmarked $300,000 for businesses along the route in the Long Branch area of Silver Spring.

The funding will be used for marketing campaigns, new signs directing customers to temporary parking, and technical help for businesses that want to expand their social media presence, officials in both counties said.

“At the end of the day, we want a diverse set of businesses along the corridor,” said Prince George’s Council Chair Dannielle M. Glaros (D), whose district includes much of the Purple Line alignment through the Riverdale area. “We want our Mom and Pop businesses to not only survive construction but to thrive when the Purple Line opens.”

Tina Benjamin, manager of special projects for Montgomery County Executive Isiah Leggett (D), said the $300,000 has been in the county’s capital budget for five or so years for redevelopment in Long Branch. She said the money was never spent, so the county “reprogrammed” the funding.

She said county officials didn’t consider any proposals to help businesses along other parts of the 16-mile Purple Line alignment.

The counties’ funding came after a state legislative proposal that would have offered business owners state tax credits for lost revenue failed this spring in the Maryland General Assembly. Maryland Transportation Secretary Pete K. Rahn had said that he sympathized with the business owners, but that he was concerned that compensating them financially would set a precedent for hundreds of transportation projects statewide.

Purple Line project officials have told some business owners along the 16-mile alignment that they will lose much of their parking during construction and could lose water and power at times. One bar owner in downtown Bethesda recently said business has dropped 20 percent since his street closed for construction, which started last fall.

Some state lawmakers representing business owners along the project said it didn’t make sense to build a light-rail line in hopes of generating economic development around stations if businesses didn’t survive its construction. The line is scheduled to begin carrying passengers in 2022.

Gerrit Knaap, executive director of the National Center for Smart Growth Research and Education at the University of Maryland, said he and others in the Purple Line Corridor Coalition are applying for business assistance grants from foundations and the federal government.

“It will be hard for them to maintain a client base during a period when there will be trucks and holes in the ground and dust in the air,” Knaap said, “so they’ll need help getting through the construction period.”

After the line opens, he said, “They’re going to have to try to capture additional revenues to cover higher rents. It will require a new business model.”