Two new flights helped lift commercial airline passenger numbers through Charles M. Schulz–Sonoma County Airport north of Santa Rosa last month nearly 30 percent, and a new Southern California route is set to start this month.

Amid a steady rise in airline passengers, the number traveling through Santa Rosa in February rose 28.9 percent from a year before, based on figures released March 2 by the county of Sonoma, which runs the airport. Alaska Airlines is the only commercial carrier serving Santa Rosa.

Since January 2015, the airline passenger count gone up every month. In February, 20,554 traveled through the facility, compared with 19,979 in January, a rise of 2.9 percent, and 15,951 the previous February.

The overall increase was mainly due to a third flight to Los Angeles and a second flight to Seattle, according to airport officials. A route between Santa Rosa and Orange County is set to start March 16.

The airport saw a slight increase in ridership as well. The load factor — how full the seats were on each plane — was 77 percent last month, up 1.4 percent.

In February, there were 174 arrivals and 173 departures.