Maryland State Highway Administration officials say they will double the size of the park-and-ride lot in Davidsonville to accommodate an increase in commuters.

The Davidsonville lot, located near the intersection of Route 424 and U.S. 50, has always been well used, but the number of people parking at the lot increased drastically when the Maryland Transit Administration reintroduced two commuter bus lines in 2010, according to SHA spokesman Charlie Gischlar.

The Route 922 and Route 950 commuter buses stop in Davidsonville as part of their routes between Kent Island and Washington.

"Almost overnight, we went from 75 percent usage at the Davidsonville lot to over 100 percent, with people parking all over the place," Gischlar said.

During busy weeks, especially in spring and fall, some drivers resort to parking along Route 424 when the lot is full.

The state will spend $1.7 million to add 200 spaces to the 200 now at the lot, Gischlar said.

He said when larger park-and-ride lots such as Davidsonville regularly reach 75 percent capacity, highway officials begin researching expansion options. For smaller lots with fewer than 100 spaces, expansion plans are considered when usage hits 95 percent.

The Davidsonville lot expansion will be completed by Ardent Company of McLean, Va. Workers plan to complete the work in phases so that parking spots are not lost during the workweek.

After preliminary grading and stormwater controls, workers will first build the new spaces, Gischlar said. Then workers will direct drivers to the new spaces in order to repave the old lot.

"It will be very carefully staged," he said.

There could be some loss of spaces on weekends.

Officials say the project also will include environmentally friendly features, such as a "bioswale" that will be planted with native vegetation to slow and absorb polluted stormwater runoff. Energy-efficient LED lighting will also be installed.

The project is scheduled to be complete by summer.

pwood@baltsun.com

twitter.com/pwoodreporter