Residents and light rail train passengers here have a message for the Maryland suburbs: If a Purple Line is ever built, expect the trains to be popular, but first brace for years of construction that can be brutal for motorists and potentially crippling for businesess along the route.

Washington area drivers also would have to learn to share streets with Purple Line trains — the nearly three-year-old Phoenix-area system averaged one collision a week during its first year — and a new “ding ding” sound would fill the air. Light rail trains are quieter than Metrorail — the trains’ low hum is often drowned out by passing traffic — but the frequent bells of trains approaching intersections and stations can be heard a block or two away.

Maryland officials who hope a Purple Line would rejuvenate older communities along the 16-mile route, such as Langley Park and Riverdale, would see new development around stations, but that transformation takes time, Arizona officials say. Along the 20-mile line between Phoenix and the suburbs of Tempe and Mesa, high-rise apartment buildings, shops and restaurants have sprung up around stations. But trains still pass plenty of weed-filled lots and dilapidated buildings.

Arizona light rail passengers rave about their trains’ reliability and convenience.

“I love it,” said Guy Carpenter on a recent Monday morning as he stepped off a train near the Phoenix airport to walk two blocks to his engineering firm in a new office building near a chic new hotel. “I wish it were more extensive, but I love it.”

By the time Carpenter drives to the station, his light rail commute takes 15 minutes longer than driving, but he said the 25-minute train ride lets him get a jump on e-mail rather than fume behind the wheel. The buses had never been a good option, he said, because they were too slow.

What Phoenix now offers — more reliable public transportation, another alternative to gas-guzzling vehicles, new development rejuvenating areas around stations — is what the Maryland Transit Administration envisions for a 16-mile Purple Line between Bethesda and New Carrollton. State planners have said they expect to be granted federal permission this summer to do more detailed engineering on the $1.93 billion project. It’s still unclear where construction money would come from.

Consultants who worked on the Phoenix system are helping to design a Purple Line, said Henry Kay, who oversees projects for the MTAMTA. He said Maryland planners like the Arizona system’s sleek trains and the attention to detail in stations, such as public art and shade for waiting passengers.

“Every new project solves a lot of problems or uses new technology,” Kay said. “The industry always wants to share those with each other.”

Surprise success

Even the Phoenix system’s biggest boosters say they are surprised by its success. Ridership in 2010 — the line’s second full year of operation — averaged 39,000 on weekdays and exceeded projections by 51 percent, according to Valley Metro, the transit agency. What strikes a Metrorail rider is the less herky-jerky ride and low-profile stations. Light rail “stations” are merely 100-yard platforms with seating and an overhang in medians or along curbs.

Critics say the cost of the Phoenix line — $1.4 billion, with $646 million of that from the federal government and the rest from local sales taxes, plus $24 million in local operating subsidies annually — is too expensive and unfair to the vast majority of taxpayers who don’t live or work near it. Maryland transit officials say they estimate a Purple Line would require $18 million in annual operating subsidies.

Byron Schlomach, chief economist at the Goldwater Institute, a Phoenix think tank that promotes limited government, said it would have been cheaper to improve bus service or even drive people in small shuttle vans.

“It’s a very costly system for what’s being accomplished,” Schlomach said. “There are a relatively small minority of people who like to live in the kind of urban environment that light rail benefits, but they’re few and far between. . . . It doesn’t serve the bulk of the community well.”

But those who can’t afford a car — people whom Maryland planners say would be a prime market for a Purple Line — say their previous bus commutes have been cut in half.

Randi Bembry, 21, said she used to spend at least two hours taking a series of buses to work as a U-Haul sales employee in downtown Phoenix. Now she takes one bus to the train, cutting her commute to about an hour.

“It’s really reliable,” Bembry said after stepping off the train. “It’s always on time. I can’t say that for the buses. The bus is always late.”

College student Preston Thymes, 20, said he takes the train for 45 minutes to Arizona State University in Tempe, a vast improvement over his previous 21 / 2-hour bus ride.

“Light rail has made a huge difference in the way of life around here,” Thymes said as he walked to the ASU campus, three blocks from a station. “Before people didn’t leave campus much, or they only left to go home or to [nightlife on] Mill Avenue. Now they explore the city a lot more.”

Safety precautions

Unlike Metrorail trains that run in their own rights-of-way, light rail trains operating on local streets must be synced with traffic lights.

In the Phoenix area, trains automatically send a signal as they approach any of the 150 intersections. Depending on traffic volumes in the opposite direction, the signal usually favors the approaching train with a slightly longer green light or with a shorter red light if it arrives after the green cycle, Valley Metro spokeswoman Hillary Foose said. Motorists are then given red arrow lights to caution them against turning across the tracks when a train is approaching, Foose said.

The Arizona transit agency spent $300,000 on a two-year safety campaign as the system opened. Even so, train operators, motorists and pedestrians are still learning how to stay out of one another’s way. After 52 collisions the first year, the second year saw 25, and this year is on pace to match that, according to Valley Metro figures.

Most of the collisions have been fender-benders, and no one has been seriously injured or killed, Foose said. No train operators have been cited in any collisions, she said, but police have ticketed motorists for turning across the tracks illegally on a red signal.

“I think it’s a combination of impatience, distraction and why else people run red lights,” Foose said. With tourists and people constantly moving into the area, she said, “I think it’s always going to be a challenge for us.”

Patience required

Residents say their biggest challenge was living through construction. Because light rail is designed to serve the most dense residential and commercial areas, the streets where tracks are laid are some of the busiest and most difficult to avoid.

Brad Brauer, who lives three blocks off the Central Avenue line, said he enjoys taking the train out for drinks and to Phoenix Suns basketball games. But living off a major thoroughfare that was ripped up for three years as underground utilities were relocated, tracks were laid and sidewalks were rebuilt, required plenty of patience, he said.

“It changes your life for quite some time,” said Brauer, a real estate agent. “People just stayed away from Central. There was just no way for people to get there easily.”

Foose said Valley Metro spent $5.5 million to help businesses along the route before and during construction by erecting signs, organizing promotional events and offering business counseling and loan programs.

“We learned it’s important to start that communication early about [business] assistance programs rather than when construction is outside your front door,” Foose said.

Nathan Johnson, who co-owns a flower shop near a Tempe station, said about 10 businesses near him closed during construction. He said his family’s 84-year-old store survived only because he took out more loans to cover expenses.

So far, light rail passengers aren’t getting off to buy flowers, he said. Even so, Johnson said he believes the early development that the rail station attracted — primarily new apartments with street-level stores replacing run-down buildings — caused his property value to double before the local real estate market crashed.

“That’s probably the most effective benefit of light rail,” Johnson said. “For 20 years we were in decline, and then light rail came, and it cleaned up the street. A lot of the seedy motels and prostitution are pretty much gone. It brings a lot of money to the area.”

The line has generated $4.2 billion worth of public and private development built or under construction within a half-mile of the route, according to Valley Metro.

Attracting investment

Trains still pass plenty of worn strip malls and vacant lots. The main reason, local officials say, is that the line opened just as the tanking economy hit the Southwestern real estate market particularly hard. They expect light rail stations will be the first places developers invest once the economy recovers.

Tempe Mayor Hugh Hallman (R) said he initially objected to taxpayer subsidies for light rail. But he said he changed his mind after seeing the transformation of a dilapidated stretch between downtown Phoenix and Tempe. The city of Tempe had spent “tens of millions of dollars” over three decades trying to attract the kind of investment that the light rail line drew in just a few years, he said.

As high-rise condo and apartment buildings went up with new street-level stores around stations, he said, nearby neighborhoods attracted new residents who spruced up older homes.

“As a transportation investment,” Hallman said, “the payment back to the community pretty well takes care of the investment.”