The main terminal and control tower of Washington Dulles International Airport. (Photo courtesy of the Metropolitan Washington Airports Authority)

The Metropolitan Washington Airports Authority’s board of directors is slated to meet on Wednesday and has a number of items on its agenda, including the latest news on the Silver Line rail extension and updates on a series of internal audits examining everything from employee travel to toll road collections.

Also on the agenda, is an update on air traffic statistics for the month of August. Within those numbers is some good news for Dulles International Airport: Passenger traffic increased 0.9 percent in August — the first such increase since May 2011. The bump largely was due to an increase in international travel.

While Dulles has continued to post strong international numbers, its domestic business has declined. In August, the number of domestic passengers declined 2.5 percent, while the number of international passengers increased 8.2 percent. In total, 2.1 million passengers traveled through Dulles in August.

By contrast Reagan National posted a 1 percent decrease in passenger activity in August. MWAA officials said the decrease — a rarity for an airport which has been booming — was due to cuts in service by United and Frontier airlines. Spirit Airlines also recently discontinued service from Reagan. In total, 1.8 million passengers traveled through Reagan in August.

The board’s Audit and Legal Committee will receive an update on a series of audits that have been conducted. In most instances, the audits evaluate how well MWAA officials or contractors hired by the authority are adhering to rules and standards. While the presentations are brief, they do offer some insight into areas where more scrutiny may be needed into MWAA operations.

The board also will receive its monthly update on progress of the first phase of the Silver Line rail extension. MWAA officials said at the meeting last month that they expect to turn over the project next month to officials at the Washington Metropolitan Area Transportation Transit Authority. WMATA is expected to conduct testing on the rail system in preparation for opening it to passenger service.