Maryland will be able to build highways and upgrade its mass transit system because of a federal transportation bill that was recently approved after a two-year delay, state and federal officials say.

With the state scheduled to receive more than $4 billion over the next six years, the construction of the intercounty connector and plans to add rail cars to Metro can proceed, officials say. Numerous other projects across the region will also be funded under the $286 billion bill Congress approved late last month.

Maryland will be able to continue construction on several projects and begin others that have long been in the pipeline. And some of the money will be used to study future endeavors.

"We are talking about projects that reach into every corner of the state," said Robert L. Flanagan, the state transportation secretary.

Maryland will receive $583 million a year for the next six years for highway improvements and construction, and it will get a total of $846 million for mass transit projects. The state was authorized to proceed with what are known as the Bi-County and Corridor Cities transit.

Also called the Purple Line, the bi-county project would be a Metro line that could eventually connect southern Montgomery County and Prince George's County. The corridor cities project, a proposed light-rail link between Frederick and Shady Grove, was also authorized.

Both projects are now eligible for planning, design and construction money. But because they still must clear legal and funding hurdles, construction wouldn't begin for years.

Other transit projects, most notably the boosting of Metro trains from six to eight cars, will proceed much more quickly. Congress approved $100 million for the Metro cars.

Ragina Averella, manager of public and government affairs for AAA Mid-Atlantic, said the money is "a shot in the arm for our ailing highway and transit systems."

"The passage of this bill is critical to Marylanders . . . although it's been a long time coming," Averella said. "We believe this much-needed federal funding will aid in reducing gridlock and the long commutes Marylanders face."

Flanagan said the federal funds will become part of Gov. Robert L. Ehrlich Jr.'s six-year, $12 billion transportation plan.

"This bill is the final piece of the puzzle that has been put together by Governor Ehrlich to support both highway improvements and public transit," Flanagan said. Last year, Ehrlich (R) and the General Assembly raised vehicle registration fees by 87 percent to pay for transportation projects.

Ehrlich hopes to break ground next fall on the $2.4 billion intercounty connector, his top transportation priority, which would connect Interstate 270 in Montgomery County with Route 1 in Prince George's County. Congress appropriated $18 million for the project.

Several other projects are underway or will be soon.

In Charles County, construction of the Hughesville bypass should be completed next year, Flanagan said. Congress allocated $11 million for it.

Construction of a new interchange at Interstate 70 and Route 85 in Frederick County is scheduled to begin this fall. Work on a proposed interchange at Route 32 and Burntwoods Road in Howard County is set to begin in the spring of 2007. And the widening from two lanes to four of Route 124 in Gaithersburg from Warfield Road to Midcounty Highway is to start in two years.

Several members of Congress also secured funding for projects in their districts. There are 101 such Maryland projects in the federal bill.

In Montgomery, Rep. Albert R. Wynn (D) and Rep. Chris Van Hollen (D) announced $21 million to build a transit center in Silver Spring. The site will serve as a key crossroads for bus, MARC and Metro service.

Van Hollen also secured $1.6 million for engineering and construction of a new interchange where Route 355 meets Montrose and Randolph roads.

In addition, $4 million in federal funds requested by Van Hollen will be used to improve pedestrian access in Rockville and Wheaton and in Mount Rainier in Prince George's County.

In Prince George's, Wynn and Rep. Steny H. Hoyer (D) announced $15 million toward a new interchange at Route 4 and Suitland Parkway and money to build a new flyover ramp from the inner loop of the Capital Beltway to Route 5.

Rep. Benjamin L. Cardin (D) announced $12.5 million to expand Route 175 in Howard and Anne Arundel counties.