NORTH COUNTY -- Even if extra money is found to pay for widening Highway 78 between Escondido and Oceanside, motorists driving the freeway in 2030 will have to put up with the same stop-and-go traffic they face today, a planner said Thursday.

The San Diego Association of Governments, San Diego County's regional transportation planning agency, is in the process of writing a new blueprint for freeway, rail and bus improvements between now and 2030.

As a result of skyrocketing construction costs, the agency disclosed recently that it won't have enough money to beef up Highway 78 if it concentrates limited funds on Interstates 5, 15 and 805.

To avoid condemning North County's primary east-west artery to ever-worsening congestion, the agency is hoping to raise additional funds by boosting gasoline or sales taxes or introducing new fees.

Under the assumption that billions will be found, the agency included Highway 78 improvements in its $58 billion draft 2007 regional transportation plan released in June.

Final approval for the plan is anticipated in November.

The improvements will help for a few years, but by 2030, congestion will be as bad as it is today, said Mike Hix, a principal planner for the association.

"What we're proposing in the plan isn't enough," Hix said. "It looks like on the east end, especially, that it won't be enough."

Hix delivered the sobering news to an audience of about 25 North County residents who attended a community workshop on the plan at the San Marcos Civic Center this week. Many of the questions that surfaced at the workshop dealt with Highway 78.

The road is a six-lane freeway between Interstates 5 and 15, and serves as the main link between coastal and inland North County. In Escondido, it changes into a winding two-lane state highway that leads to Ramona, Julian and Anza-Borrego Desert State Park.

"When 78 was first built, it was basically built as a rural highway," Hix said.

Now, he said, it is poised to become an eight-lane freeway between Oceanside and Escondido, with the six existing general-purpose lanes and two new car-pool lanes. The association's proposed $863 million expansion also envisions special ramps that would drop car pools directly into express lanes being built on I-15.

The plan calls for building the lanes and ramps sometime between 2020 and 2030.

At the workshop, San Marcos Mayor Jim Desmond stressed the need to build the projects sooner rather than later.

"We can't wait until 2030 to fix it," Desmond said. "Our surface streets will just fail."

San Marcos resident Peggy Johnson said that city streets already are under enormous pressure because of the congestion that plagues Highway 78.

"Everybody's on the surface streets, trying to cut through town," Johnson said. "Nobody gets on the 78 anymore because it's insane."

Her husband, retiree Brian Johnson, said he avoids the highway like the plague if he has an appointment in Escondido after 2 p.m. in the afternoon.

"I'll take Mission, I'll take Barham, I'll take any other way into Escondido before I'll take 78," he said.

When the car-pool lanes get added, they will provide relief for motorists traveling on that east end. But the relief will be short-lived, Hix said.

He said the association's computer models show stop-and-go traffic returning to the section between Twin Oaks Valley Road and I-15 by 2030, and possibly to other spots farther west.

Part of the problem, Hix said, is that there is no room for more than two additional lanes -- and those will be a tight squeeze as it is.

Hix said the association is hoping that the Sprinter light-rail line, scheduled to debut this December, will take some pressure off the freeway. But the train won't be enough, either. At some point, he said, the region will have to figure out another way to accommodate the swelling numbers of people traveling back and forth between coastal and inland North County.

Contact staff writer Dave Downey at (760) 740-5442 or ddowney@nctimes.com.