The vote paves the way for construction of the resort, which could open in July 2016.
The casino is slated to have 3,600 slot machines and 140 table games. Plans also call for a 300-room hotel.
MGM officials now will seek a building permit, which could be obtained next month.
The council heard presentations last Monday on the site and traffic plan for the $925 million casino.
“Right now we have grading permits, and the next step will be go get building permits,” said MGM’s attorney Arthur Horne.
He says a successful vote will mean the site plan for the project can get certified, which will then allow for MGM to pull the permits it needs.
“We’re hoping to get the building permits in the end of July. That may move into the first or second weekend of August,” Horne said.
During last week’s meeting, the Maryland-National Capital Park and Planning Commission presented the applications received for the project, including a study on the impact the casino will have on traffic.
The study found that the casino, which will have a theater, will see the most traffic around 7:30 p.m., two hours after the peak time for the normal daily rush.
Some people who live near the future home of the casino say they are not satisfied with the plans.
Will Nuckols lives near the site and says the traffic study didn’t account for special events and big shopping days at National Harbor.
“It’s not that we want to keep people away and say,