The City of Seattle says operating its own broadband service would be too expensive, but that hasn’t stopped some activists from pushing the idea forward.

Those continuing to pursue the idea include Seattle City Council member Kshama Sawant, who is supporting Upgrade Seattle, a volunteer, grassroots group pushing for the city to launch its own service.

“We’ve had many studies, we don’t need any more studies,” Sawant said. The latest study shows there are viable options and there is a public mandate, she added.

But a number of city leaders dispute that. They cite the report from this spring that says it would cost upwards of $630 million to get the network off the ground.

Mayor Ed Murray has determined it isn’t worth the risk to compete against Comcast and CenturyLink, even if a survey found 65 percent of residents favored it.

But Sawant and other advocates point to Chattanooga, Tennessee, which launched a utility-run gigabit broadband service. There, customers get 1 gigabit for about the same price Comcast charges for far less speed.

“This is about making Seattle truly a 21st Century city,” Sawant said. “This is a hub of high-tech businesses.”

Among their arguments: that Internet access is no longer a luxury, but a utility. And providing equal access is a key obligation of the city.

But it won’t be easy. Sawant said the big boys won’t take the competition without a fight.

“In Chattanooga [Tennessee], Comcast went to war against the idea of municipal broadband. They launched 2,600 attacked ads on television and filed four lawsuits against the city,” Sawant explained.

But for those of us who actually live in Seattle, it’s certainly an intriguing idea. Far greater speeds for the same price or even less. And advocates say as a utility, we’d get things like redundancy, so when a line gets cut, it doesn’t take out the entire area and hours to fix it, because there would be backups the private companies don’t invest in.

In fairness, Comcast has continued to increase speeds, and CenturyLink has been adding fiber and gigabit service all over the city.