Amazon’s Web Services division plans to add 500 tech-related jobs in Fairfax County. (BLOOMBERG) plans to add 500 employees to its Fairfax County Web Services business, further cementing the Dulles Corridor as a major center for information technology and big data storage.

Virginia Gov. Robert F. McDonnell (R) made the announcement, highlighting the Seattle-based online retail giant’s growing role as a computer storage provider through its Amazon Web Services division, which the company established in 2006.

In a news release, McDonnell said Amazon will create a Herndon area office “to support engineering and services for commercial and government customers of AWS cloud services.”

The jobs are expected to pay an average of at least $100,000 a year. An Amazon spokesperson declined to provide more specifics, such as when the jobs would be added.

Western Fairfax and parts of Loudoun County are home to a major telecommunications artery, known as MAE-East, that serves as a key Internet hub on the East Coast and connects a growing network of data centers and other technology infrastructure.

“Virginia has delivered and has once again stood apart from the other jurisdictions,” said Raul Fernandez, who has been active in local technology circles since the 1990s and is now vice chairman of Monumental Sports & Entertainment. “The derivative effect, the other jobs that are created out of these Amazon jobs, will be significant. This adds to the diversification of the employer base in the region.”

Alhough Amazon Web Services has been expanding its reach into federal agencies in recent years, the company does not rely entirely on the government for revenue. That helps balance Fairfax County’s contractor-heavy economy, especially as sequestration diminishes government spending, said Gerald L. Gordon, the president and chief executive of the Fairfax County Economic Development Authority.

McDonnell approved a $500,000 state grant to assist Amazon’s recruitment and training.

Fairfax County agreed to match the state contribution with $500,000 to improve roadways near the firm’s new headquarters, which will require turn lanes to handle increased traffic.

“[When] you get an employer like this, with high-paying jobs, you end up with other companies generally locating around them. You end up with restaurants and other retail. So things like intersection improvements become critical,” Gordon said.

The expansion follows an announcement this month by Amazon Web Services that the federal government had put the company on a fast track to sell it cloud computing services.

The company has been gearing up to exploit the federal market since 2010, when Amazon hired Teresa Carlson, who headed Microsoft’s federal business, to lead its public sector group.

The company has jumped into cloud computing work as well as the government’s increased focus on Big Data, or huge sets of information that aren’t easily managed by typical computer programs.

Marjorie Censer and Steven Overly contributed to this story.