King County Metro Transit will update its service on more than 80 bus routes starting Saturday.

The Metro Transit service changes include adding or reducing trips, adjusting schedules, or changing routing.

The most significant revisions include:

• New Metro Route 156 service between Southcenter and SeaTac, replacing portions of the current Route 140;

• Route 140 routing adjusted to serve the Tukwila International Boulevard Link light rail station. Route 140 will no longer serve Sea-Tac Airport, which will reduce travel time between Burien and Renton on that route;

• Bus-service revisions at Sea-Tac Airport to connect Metro and light rail service at the new SeaTac/Airport Link station;

• Discontinuation of Metro Route 194, now that light rail serves the airport;

• More frequent service on routes 8, 9, 36 and 60 in southeast Seattle as Metro makes a second set of service changes to better connect bus service with light rail;

• More bus trips on existing routes between West Seattle, SODO, and downtown Seattle to keep people and businesses moving during the first stages of Alaskan Way Viaduct construction;

• Moving routes 76, 77, 216, 218 and 316 into the Downtown Seattle Transit Tunnel;

• Long-term reroutes related to construction in the Northgate area for routes 73, 77, and 373; and

• Trip reductions on approximately 40 Metro routes.

While the number of trips on some routes will be reduced to deliver more efficient service, overall those reductions will be offset by expanded service on other routes in the next two years, according to a Metro Transit press release.

Metro projects a slight increase in total service hours through the end of 2011 as a result of scheduling efficiencies and new partnerships.

The increase in service between West Seattle and downtown Seattle will help mitigate impacts associated with early work on the Alaskan Way Viaduct. The Washington state Department of Transportation is contributing approximately $30 million, which will allow Metro to increase frequency on several routes. In future months, Metro will seek funding for additional service when the central waterfront and bored tunnel are under construction.

Also beginning Saturday, Metro will allow bicyclists to load and unload bicycles at any regular bus stop in downtown Seattle’s Ride Free Area at any time of the day. This will be a one-year demonstration project. Over the past several years, Metro has eased its limits on bike loading at regular stops. The restrictions during peak hours in the busy downtown core are the last in place. Once they are lifted on Feb. 6, Metro will do a one-year safety and operations evaluation to decide whether to make the changes permanent.

Metro updates its routes and scheduling three times a year to improve service and keep up with the changing needs of transit customers. The entire February service change is posted online, and route-specific information is available in the new red timetables.

Bus riders can also find the February changes detailed in the Special Rider Alert brochure available on buses and in Metro information racks. Information is available in the Trip Planner. Enter a travel date for Feb. 6 or later to find trips that reflect Metro’s changed service.

Metro customer information also is available by phone at 206-553-3000.