It costs taxpayers more than $57 for each rider to take the Sounder commuter train from Everett to Seattle — and that’s just one way.

For Sound Transit Express buses, it costs taxpayers $4.33 for each rider between the same destinations.

The standard adult train fare between Everett and Seattle is $4.50. The bus fare is $3.50.

That’s why the agency should discontinue the Sounder north line and replace it with more buses, according to a retired transportation planner from Bellevue who crunched the numbers. He based his conclusions on operating and capital costs and ridership figures over the next 30 years.

“If properly informed of the situation, Snohomish County taxpayers should be pressing to stop continuance of Sounder north,” James MacIsaac said in a letter to Sound Transit in January.

Sound Transit officials dispute MacIsaac’s method — he includes capital costs in cost-per-rider figures while Sound Transit does not, per industry standard.

Still, Sound Transit’s own figures show cost-per-rider at $32 last year without capital costs, compared to about $7 for Express buses systemwide.

One of the biggest expenses for the system is $258 million the agency paid up front to Burlington Northern Santa Fe Railroad for the permanent right to use the rail lines between Seattle and Everett. MacIsaac counted this payment as a capital cost in his cost-per-rider numbers, along with stations, trains and other costs.

This access to the rail line is a long-term investment that will pay off in the future as the population grows and the roads become more congested, Sound Transit spokeswoman Kimberly Reason said.

“It was really a pioneering move because we have access to that rail line forever. You really can’t put a price tag on that,” Reason said.

MacIsaac, 70, worked for the precursor of today’s Puget Sound Regional Council, a planning organization, in the 1960s. He ran his own transportation planning firm, the Transpo Group, from 1975 to 1995, and worked as an independent consultant afterward.

MacIsaac in January sent a report with all his calculations to Sound Transit. It’s been forwarded for review to the agency’s Citizen Oversight Panel, a 13-member group that provides input to the staff and board of directors.

Sounder commuter rail and Express bus service both were approved by voters in 1996 as part of the original Sound Move ballot measure.

Last year, nearly 10 times as many trips were taken on Sound Transit Express buses between Everett and Seattle than on the Sounder — roughly 2.3 million versus 280,000.

The Sounder figure includes an average of 515 riders each way per weekday in 2011. It also includes 48,000 riders who took the train to sporting events on weekends during the year.

By contrast, Sound Transit Express buses between Everett, Edmonds, Lynnwood and Seattle carried about 3,950 people a day each way, according to MacIsaac’s figures.

Sounder trains runs eight trips per day, four each way, while the 510 and 512 routes from Everett run a combined 161, according to a Sound Transit schedule.

Those 500-plus-per-day round trip riders on the Sounder line could be moved to new buses and commute for that much less, MacIsaac says.

Add in the fact that the Sounder north line has at times been plagued by mudslides that have forced the cancellation of many runs over the years, and that means an inefficient operation, he says.

MacIsaac said that to make his projections, he used raw data he obtained from Sound Transit through public disclosure requests. Sound Transit supplied only annual ridership and cost figures for the past few years.

Harold Wirch of Brier, who recently retired from the Snohomish County public works department, is on the Citizen Oversight Panel. He said a sub-group has been formed and has just begun examining MacIsaac’s report.

“You really need to take a look at everything,” he said. “We don’t want to jump to conclusions.”

Everett City Councilman Paul Roberts, a member of the Sound Transit board of directors, said Sounder north ridership is a legitimate concern, but that it doesn’t mean the service should be discontinued.

The trains began running between Everett and Seattle in December 2003. After ridership hit an all-time high of more than 1,200 riders per day in June 2008, it began a slow decline, hitting a low of fewer than 800 per day in late 2010, according to agency figures. That winter the line was plagued by a record number of mudslides.

Ridership rebounded in 2011 and in January of this year, but agency officials are nonetheless discussing how to increase ridership, Roberts said.

“It’s a fair question and we need to see if we can’t do better. They’re trying to set up some discussions and brief us in more detail,” Roberts said of Sound Transit staff.

Ridership on the southern Sounder line from Tacoma to Seattle, a longer trip with more stops and nine trains per day each way, is much higher than in the north: about 2.5 million trips were taken last year, an average of nearly 9,500 per weekday. The operating cost per rider last year was slightly more than $10, according to Sound Transit figures.

Mukilteo Mayor Joe Marine, also a member of the Sound Transit board, said one way to increase ridership on the north line would be to add parking at the Sounder stations in Edmonds and Mukilteo.

The parking lots are full to overflowing every day, he said. Sound Transit already is planning to add parking in Mukilteo.

“How can you possibly get more ridership if you can’t get people down there?” he said.

Either way, Marine said, the $258 million investment for the right to use the rail line has been made.

“Even if we stop it tomorrow, none of that goes away,” he said.

MacIsaac says Sound Transit’s belief in future ridership doesn’t hold up based on its own figures. He notes that the agency predicts 310,000 trips in 2030 — only a modest increase from today and still far fewer than buses.

Sounder is limited in part by the fact that the railroad so far has not agreed to allow Sounder to run more than four trains per day each way even though the agency paid $258 million. Much of the line is a single track that Sounder and Amtrak must share with freight trains.

MacIsaac said other factors favor buses as well. They make multiple stops in downtown Seattle while Sounder stops only at King Street Station, and the buses generally take less time to travel from Snohomish County to downtown than Sounder.

On the other hand, as noted in a Sound Transit PowerPoint presentation, the state recently received more than $16 million in federal money for mudslide prevention projects. The agency contends that in the long term, population and employment growth will increase demands for all kinds of public transportation.

It’s one thing for ridership not to meet expectations, but it’s another to conclude that the service should be discontinued, Roberts said.

“It’s very easy to take a snapshot in time today,” he said, “and say, ‘Let’s make a decision that’ll have an effect 50 years out.’”

Bill Sheets: 425-339-3439; sheets@heraldnet.com.