[This post has been updated.]

Both houses of Congress have approved an appropriations bill for transportation that will have two major impacts in the D.C. region. It provides much-needed money for Metro and changes the makeup of the board that governs Dulles and Reagan airports.

The bill, which President Obama signed Friday, expands the size of the board of the Metropolitan Washington Airports Authority (MWAA) from 13 to 17 and would allow members to be removed by their appointing bodies — moves that Congressman Frank R. Wolf (R-Va.) has been pushing. Its members serve six-year terms and are not paid.

The transportation bill will also give Metro $150 million to help improve its deteriorating system. The money is part of a federal funding commitment to spend $1.5 billion over 10 years to improve Metro safety and infrastructure. It requires a match from Maryland, the District and Virginia.

MWAA also oversees the construction of the new Silver Line to Loudoun County, which Metro will operate and maintain.

Wolf’s legislation expands the airports board from 13 to 17. Virginia would get two new appointments and Maryland and the District would each get one additional member. Of the 13 members currently on the board, five are from Virginia; three from the District, two from Maryland and three are federal appointees.

The bill also prohibits members of the MWAA board from serving past the end of their terms. Members could be “removed for cause.”

The governors of Maryland and Virginia and the mayor of the District could remove their respective members. The executive branch of the federal government already has that authority.

MWAA’s board voted in September against the changes Wolf had proposed to its board.

Watchdog groups have expressed concern about the airports authority’s operations and the board’s oversight.

It was unclear Friday if Virginia and the District, parties to the compact governing the airports authority, have to approve the change.

“We’re studying the bill and any available supporting language to understand what is required to have the changes implemented,” airports spokeswoman Tara Hamilton wrote in an e-mail.

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