The Seattle Monorail Project (SMP) yesterday issued a new finance proposal designed to pay for a shortened line in less than four decades.

With a fifth monorail vote Nov. 8, three weeks remain for backers to convince the public that the new $1.7 billion, 10-mile route from Interbay to West Seattle's Alaska Junction is a good deal.

With interest costs included, the shorter route would cost up to $4.9 billion over 38 years. That's $6.5 billion less than an earlier $11.4 billion package, announced in June, that included some high-interest "junk" bonds.

"There's no magic to it. We reduced the cost of the project, and therefore you need less money and less debt service to build," board member Paul Toliver said at a meeting last night.

Three years ago, a thin majority of voters approved new car-tab taxes for a longer 14-mile, 19-station line that included three stops in Ballard. But a revenue shortage and rising costs have nearly doomed the monorail, and the agency drew sharp criticism this summer for a finance plan that required at least half a century of taxes for a $2.1 billion line.

Monorail board members dropped that proposal. They later capitulated to a revote after city leaders yanked a street-use agreement for monorail construction.

Yesterday, the agency said it could pay for the first 10 miles within 31 years, if tax revenue grows at the 6.1 percent annual rate its economists predict. City Finance Director Dwight Dively and Sound Transit's forecaster, Dick Conway, have suggested 5 percent or less. At 5 percent, SMP thinks the debt would be paid in 38 years.

John Haley, the SMP's interim executive director, said the tracks would still have to withstand the most-severe earthquake expected, even though SMP could have saved $50 million to $60 million by easing the standard, he said.

The route is still envisioned to wind through Seattle Center grounds, continue on Fifth Avenue through Belltown, then shift to Second Avenue near the Pike Place Market.

Board member Cleve Stockmeyer had suggested saving perhaps $80 million by skipping the Center and going straight down Second.

At this point, "It would be a shame to start with a clean sheet of paper" because a deal with builders is nearly "ready to go," Haley said. "If voters do not approve the project and the agency goes away, what's the alternative?"

Ben Porter, a transit economist and monorail skeptic, called the latest figures "a stronger plan" but still too optimistic.

The finance plan is not required under next month's Proposition 1, which would give the agency broad authority to shorten, extend or lengthen the route, subject to city review.

The agency did not release detailed cash-flow information last night.

Opponent Henry Aronson called Proposition 1 a "blank check" for an agency that withheld news of a $300 million cost increase from the public a year ago.

Stockmeyer has said a final plan would have to win city permit approval. "In effect, the City Council is the monorail board," he said.

Mike Lindblom: 206-515-5631 or mlindblom@seattletimes.com