CBS Radio will start an all-news station in the Washington area next year, taking on news powerhouse WTOP for a share of the lucrative market for round-the-clock news, weather and traffic broadcasts.

WTOP, which has not had a direct competitor for decades, is by far the dominant station in news-hungry Washington, with the highest annual revenue of any station in the nation.

But New York-based CBS — which operates profitable all-news stations in New York, Chicago, Los Angeles, Philadelphia and other cities — sees Washington as ripe for another station offering news, particularly local news.

The new station, whose call letters have not been determined, will broadcast at 99.1 FM, currently the home of CBS-owned WLZL, a Spanish-language music station and the former dial position of beloved rock station WHFS.

CBS said WLZL, known as “El Zol,” will move to 107.9 FM, a frequency that CBS will buy from Family Stations of California. The news station will promote itself as “All-News 99.1” and will debut next year.

CBS Radio will launch an all-news station in 2012, challenging local powerhouse WTOP. (Astrid Riecken/FOR THE WASHINGTON POST)

“I’ve [worked] in New York and Washington, and I can tell you, the appetite for news in both markets is really intense,” said Steve Swenson, an all-news radio veteran who is CBS’s top manager in Washington. Regarding WTOP, he said, “I don’t look at this as going up against Goliath, or we versus them. I look at this as an expansion of the news market.”

The new station will have a formidable competitor in WTOP, the Washington area’s most popular radio station. WTOP’s formula of brief news reports and “traffic and weather together” every 10 minutes draws a massive audience of traffic-trapped commuters. At most hours, its share of the radio audience is double that of its nearest competitor.

WTOP racked up $60 million in ad revenue last year, according to the station, its most ever despite the recession. That made it the largest station in this category in the country, according to the radio research firm BIA/Kelsey. The station’s financial success is especially noteworthy, considering that Washington was only the ninth-largest market by population in the nation.

It’s perhaps because WTOP is so successful that CBS sees opportunity for a direct competitor. Although the all-news format is the most expensive to produce in radio — a station has to bear the cost of dozens of journalists’ salaries rather than simply playing music — a station that grabs just a fraction of WTOP’s ad revenue could become profitable quickly, industry experts say.

What’s more, local news is one of the few radio formats that isn’t subject to competition from satellite radio, iPods or Internet streams, all of which have eroded the radio business over the past decade or so.

“We’ve got lots of competition — it’s not just radio, it’s newspapers, it’s TV, it’s digital,” said Jim Farley, WTOP’s vice president of news and programming, in reaction to the CBS announcement. “It will be fun to compete with people we like and respect. Competition can only make us better. It will make us work better, faster and smarter.”

The CBS station will seek to differentiate itself from WTOP by concentrating its coverage on Washington’s suburbs, although it will also report stories from the District, Swenson said. It will broadcast traffic reports every 10 minutes and weather updates every four minutes or so.

The station will have eight anchors, five producer-editors and eight to 10 reporters at its launch, Swenson said. It has a program director, radio news veteran Robert Sanchez, and a news director, former WTOP news manager Michelle Komes-Dolge.

WTOP employs about 70 full-time reporters and editors and 20 or so part-timers.

CBS starts at some disadvantage to WTOP in terms of its signal strength. WTOP broadcasts primarily at 103.5 FM, a frequency that blankets much of the metropolitan area. It supplements its reach by simulcasting on two other frequencies, 107.7 FM in Manassas and 103.9 FM in Frederick.

CBS owns five Washington area stations: “urban” music station WPGC-FM, sports-talk WJFK-FM, soft-rock WIAD-FM, WLZL and WHFS-AM, which has a news and talk format.

Swenson was general manager of WTOP until 1997, when he left to manage CBS Radio’s twin all-news stations in New York, 1010 WINS and WCBS. Among those Swenson hired while he worked at WTOP: Jim Farley, who built the station’s newsroom.

One thing listeners won’t hear on CBS’s new news station: CBS News broadcasts. WTOP has an exclusive contract with the network to carry its news reports.