It is touted as light rail on rubber tires, a bus service with all the perks of rail — fast, predictable and easy to board, with nice stations and fewer stops — at a fraction of the price.

But as Minnesota's first line of bus rapid transit (BRT) begins service Saturday on Cedar Avenue S. between Apple Valley and the Mall of America, officials will be watching the $112 million project closely to see if it attracts riders, with hopes of expanding it to other parts of the metro area.

"We are developing the service that we hope will become the model for the state," said Dakota County Board Chairwoman Kathleen Gaylord.

"Everyone wants light rail. Light rail is cool, it's sexy. But in some corridors it's too much of an investment for what you are going to get out of it," she said. In terms of perks and service, Cedar BRT lands between light rail and the local bus line, Gaylord said. The question is: "Is this what people want? Will people ride it?"

Using seven new buses, the Cedar BRT line will provide all-day daily service in a continuous north-south loop between the Apple Valley Transit Station and the Mall of America. On the way, it will make two stops in Apple Valley and one in Eagan.

Its 11 miles of bus-only shoulder lanes make up the second leg of a growing network of metro transitways distinguished by "higher quality, higher amenity" service seven days a week, said Arlene McCarthy, director of Metropolitan Transportation Services for the Metropolitan Council, which owns the new busway. It's calling the Cedar busway the Red Line.

The Hiawatha Avenue light-rail line between downtown Minneapolis and the Mall of America was the first transitway segment. Cedar BRT will link Dakota County to Hiawatha — now called the Blue Line — at the Mall of America.

Then, in 2014, the third leg of the network, the Central Corridor light-rail line or Green Line, will open between downtown St. Paul and Minneapolis, connecting with the Blue Line.

"We want to keep building this network," McCarthy said. "We are trying to have a stronger transit system across the board, more of a world-class transit system."

The network of transit lines is poised to keep growing with a mix of rail and BRT service. BRT on Interstate 35W between Lakeville and downtown Minneapolis is scheduled to open in 2018. Light-rail lines are being planned for southwest and northwest Hennepin County, and Washington County is evaluating BRT and rail options.

How many riders?

With operating costs of $3.2 million a year, what kind of ridership will make BRT a success?

Everyone knows what a packed commuter bus looks like, but it's not as easy to say how full BRT buses should be when they run all day in both directions and "people get on and off and on and off and on and off," McCarthy said. "An express bus drives one way full and turns around and drives back empty."

Given the differences, McCarthy said, "I don't expect to see [BRT ridership] even-keel all day."

The Met Council projects weekday ridership of 975 in the first year of operation and 1,600 by 2017.

To meet those marks, it will have to take people to work, school, shopping and entertainment. It will be very clear how ridership is doing: The BRT's passenger counters will keep data by the hour.

Ridership won't necessarily come from the typical suburban commuter heading downtown for work. Express buses along the same route actually make fewer stops and will remain a quicker option for many commuters. BRT will supplement that service and make using transit on the Cedar corridor possible during midday, evenings and weekends when traditional commuter buses don't run.

The busway will have three years to prove itself — giving people and businesses time to locate along the line and car-wed suburbanites time to work it into their lives, McCarthy said. "When you start a new service like this, you need to give it time to mature."

As for technology, BRT buses use beams of light to count passengers as they get on. The buses carry global positioning systems that communicate with traffic signals to keep the buses on schedule. Riders will hear and see stops announced.

To get people on board, rides will be free the first week.

"I want it to be a huge success," said Will Branning, the former Apple Valley mayor and Dakota County commissioner who shepherded the project for years.

A transit alternative

The astronomical cost of building a light-rail bridge over the Minnesota River Valley between Bloomington and Eagan ruled out light rail for Dakota County, Branning said. "This is going to prove that BRT is an economical alternative to light rail. We can pump a lot of money into BRT just to make it happen because it will never catch up with the cost of putting in light rail."

Dakota County Commissioner Chris Gerlach, a former Republican legislator from Apple Valley, said the affordability of BRT compared with light rail won the project support from Republicans at the Capitol, including former Gov. Tim Pawlenty.

"To do that stretch with any kind of light rail would have been 10 times" the amount spent on the busway, Gerlach said. "Light rail would have been literally over a billion."

The fact that it's been built in phases pleases Gerlach. It will be extended southward to Lakeville as use increases, he said. "I am a conservative. I like to see a system with as little subsidy and high farebox recovery as possible."

Laurie Blake • 952-746-3287