A year ago, light rail was a promise, an untested idea in this desert, car-centric city.

On Dec. 27, 2009, Metro light rail marked its anniversary by looking back at a largely successful year while bracing for financial perils as the economy takes a toll on public funding.

The first year was one of trial, error and refinement for the new 20-mile light-rail system. Critics weren't silenced but were muted by Metro's better-than-expect-ed ridership. More than 10 million people boarded the sleek trains.

Metro's second year will determine if the agency builds on its successes or just hangs on, risking stagnation.

It's likely to be a study in contrasts, as was the first year.

On Dec. 27, 2008, Metro opened on time and on budget. Over the next 12 months, the $1.4 billion system carried an average of nearly 35,000 passengers a day, 34 percent over estimates. At the same time, Metro struggled to collect fares and averaged almost a collision a week, causing lingering doubts about light rail's safety.

This year, a new chief executive officer from Portland, Ore., arrives to oversee a system that has already laid off train operators, trimmed support staff and postponed expansions, some indefinitely, to make ends meet. Yet Mesa's downtown extension will gather momentum, and federal support looks likely.

YEAR OF HIGHLIGHTS

Before Metro opened, nobody really knew if people in a sprawling, auto-dominant region under a blazing desert sun would embrace urban trains.

May 13 was the first real test. That day, President Obama delivered the commencement speech at Arizona State University, hours before the Arizona Diamondbacks were scheduled to play in downtown Phoenix.

More than 50,000 people braved triple-digit temperatures to ride the trains that day, without a major incident.

Outgoing Metro CEO Rick Simonetta said then that it was his best day. Few rail systems had ever faced such a test so early.

"We didn't know what it would mean for ridership," he recalled. "We put everything we had out there."

By July, Metro had answered the clamor to begin late-night service on weekends. Popularity was building.

In September, Metro and US Airways Center teamed up to use Phoenix Suns' and other event tickets as train fares, in the first such arrangement in the country. The experiment worked: Metro came close to carrying 15 percent of Suns fans by train and added 11,000 passengers in the campaign's first month.

On Oct. 2, Metro carried a record 50,562 passengers. Phoenix's First Friday street fair took much of the credit.

GROWING PAINS

Metro's first year had its setbacks, too, with crashes remaining the most visible and lingering challenge.

In September, a sport utility vehicle ran a light and smashed into a train door at high speed, knocking the train off the tracks and bringing down a power pole. That was Simonetta's worst day.

"That morning I got an alert that we expected our first fatality," he said. "He walked out of the hospital at 2 p.m."

Early this month, a van ran a light and got pinched between the train and a curb. The van was folded in half against a power pole like a soda can, rupturing the fuel tank.

The two crashes have left two train cars out of service with significant damage. Other, more routine crashes have caused nearly $500,000 in damage to the light-rail system.

No one has died, and no pedestrians or bicyclists have been hit. Police have attributed every accident to motorists ignoring traffic signals.

Metro struggled with slow trains. An end-to-end trip was supposed to take 55 minutes. Initially, it took 75 minutes. For six months the schedule was unreliable. Metro was months late with automatic station announcements telling passengers their wait times.

"They sold us a sports car and delivered us a dump truck," said longtime Phoenix resident Bob McKnight, one of Metro's most studious critics.

Metro also struggled to collect its fares. Confusion about the employer-issued Platinum Passes cost Metro nearly $800,000, or nearly 10 percent of potential revenue. A Metro contractor was months late in delivering portable devices to scan the cards. Some fare inspectors still rely on a visual check and can't verify payment.

MORE UNCERTAINTY

Finances will be Metro's biggest challenge when new CEO Steve Banta takes the helm.

As of now, with layoffs, shorter trains during slow times and adjustments to the way on-call drivers are used, Metro expects to meet its $33 million budget. When the fiscal year ended in June, the agency topped its budget by less than 1 percent.

But despite a sharp fare increase, Metro still missed its cost-recovery goals. Also, Metro depends on Phoenix, Tempe and Mesa to subsidize its operating costs. Metro could face a battle to hold on to its current funding as cities face historic deficits.

Cuts could mean shorter hours or less-frequent trains when the next fiscal year starts in July. Sharp cuts could undo Metro's luxury of having busy trains throughout the day carrying people to and from more than just work.

"The light-rail system, in a lot of ways, has become a gathering place," Metro planning director Wulf Grote said.

Metro's ridership that includes tourists, event-goers and people out on the town makes the system more efficient than traditional systems that attract mostly commuters.

Longer term, the economy forced Metro to push back most extensions a year or two, and some expansions into northwest and northeast Phoenix are on hold indefinitely. It remains unclear whether Tempe will embrace a southern extension or turn to a simpler, cheaper rapid bus line, such as the LINK service in Mesa.

Once lukewarm about light rail, Mesa now seeks a three-mile, four-station extension into downtown to revitalize its community.

Mesa's prospects are good. The Sycamore station is Metro's busiest. Studies show a large demand for rail service east and south.

Metro points to more than $7 billion in public and private investment in developments within walking distance of the light-rail line.

The Obama administration has emphasized financial support for rail projects with the potential for development.

It created a new program to get smaller projects built sooner. Mesa's proposal falls within that category and is well-positioned to receive federal funding by the end of next year.

But McKnight and other skeptics remain unconvinced light rail is a wise investment.

"We're changing the whole economics of the valley, and we want to put this system in concrete. I'm sorry, that doesn't make sense to me," he said.

Rail fans such as Friends of Transit Executive Director David Schwartz say they expect ridership to steadily grow in the second year.

"I don't think you'll hear so much from the naysayers," Schwartz said. "I think light rail has sold itself."