One month after Gov. Schwarzenegger used a section of Highway 99 in Fresno County as a backdrop to tout his massive infrastructure plan, there are fears that portions of a promised $1 billion for the aging highway might disappear as the plan works its way through the Capitol.

The chief concern is a long-running one: that the central San Joaquin Valley will lose out to larger urban areas, which have more votes and carry more clout.

For instance, funding formulas might be used that steer money toward more populated areas, said Carol Whiteside, president of the Modesto-based Great Valley Center.

"Historically what happens when you do that is that areas with lower population don't get enough money to take care of their needs," she said.

The concerns led six Valley lawmakers to sign a letter this week urging support for the highway, which many see as the economic lifeline of the Valley.

Removal of $1 billion for the highway "would undermine the major reason why California's fastest-growing region should support an infrastructure bond," states the letter. It was addressed to Schwarzenegger, Senate President Pro Tem Don Perata, D-Oakland, and Assembly Speaker Fabian Nunez, D-Los Angeles.

Noting that the three leaders are from big cities, Sen. Dean Florez, D-Shafter, said, "If we don't fight to make sure that the leadership understands that this is a priority then ... it can easily be cut in half and pushed to more urban-dedicated projects like bridges and subways."

Legislative leaders continue to express support for Highway 99 spending.

"Highway 99 is a mess. It's dangerous," Perata said in an interview this week.

"It is inhibiting facile movement of trade throughout the state, so of all the things that need to get done, the spinal cord of the Valley should be at the top of the list."

Steven Maviglio, spokesman for Nunez, said Highway 99 "is a high-priority project," adding, "the speaker believes there needs to be a solution to 99."

But the fear is that the highway will get shortchanged as a compromise is worked out among competing infrastructure proposals.

Officials from across the state are angling to get a piece of whatever plan emerges. Just this week, the mayors of Los Angeles, San Francisco and San Jose visited Sacramento to urge more spending on affordable housing.

In making their case for Highway 99, Valley lawmakers noted in the letter that goods movement via truck traffic accounts for 19% to 27% of the traffic on the highway, compared with 9% statewide.

"This estimate is a clear indication that Highway 99 is clearly an essential component to long-term growth of the state's economy," the letter states.

The letter is signed by Florez and fellow state senators Roy Ashburn, R-Bakersfield, and Jeff Denham, R-Merced, along with Assembly Members Nicole Parra, D-Hanford, Juan Arambula, D-Fresno, and Mike Villines, R-Clovis.

In addition to the governor's plan, infrastructure proposals have been put forward by Assembly Democrats as well as Perata.

Assembly Republicans have emphasized a "pay as you go" approach that would set aside a portion of the budget each year for projects.

In order to put an infrastructure bond on the June ballot, a compromise must be reached by March 10.

So far, the nonprofit Great Valley Center is supporting the governor's plan, "but if other proposals pony up to the bar, we'll support them too," Whiteside said.

Schwarzenegger's proposal dedicates $1 billion to Highway 99 out of a planned $68 billion in infrastructure bond issues that would be placed before voters in stages between now and 2014.

Assembly Democrats unveiled a plan this week that called for roughly $30 billion in bonds spread over two election cycles.

The plan's transportation component is short on specifics at this point. Among the priorities are congestion relief and more money for public transit, according to a statement from N??ez's office.

Perata's plan calls for a $13 billion bond that includes money for flood protection, roads, bridges and ports.

It would distribute $1.5 billion to the State Transportation Improvement Program.

Known as STIP, the program distributes road money to regions based partly on formulas that give weight to population and road miles.

The program has been underfunded in recent years as gas sales tax revenue was diverted to the general fund.

Valley transportation officials are worried that if new infrastructure spending relies too heavily on formulas, there might not be enough for Highway 99, stretches of which run through sparsely populated regions.

They favor the governor's plan because they say it reserves a set-aside amount for the highway.

"The other plans do not address that at this point," said Barbara Goodwin, executive director of the Council of Fresno County Governments, whose mission is regional transportation planning.

Sen. Chuck Poochigian, R-Fresno, who did not sign the letter, cautioned against relying too much on set-aside spending because he said it's a scenario under which areas like the Valley often lose.

Formula spending, by contrast, "tends to be more protective in the ideal for areas that have less political clout," he said.

Perata indicated a willingness to reserve money for Highway 99, saying it could be listed as a "priority statewide project."

The rise in popularity of inland ports has made the highway a critical trade route, he said.

His plan calls for $2 billion to make "highway, rail, or port infrastructure improvements in the state's most heavily congested trade areas."

"In trade infrastructure, the Valley's playing a brand new role," he said. "And the state needs to support that role."

The reporter can be reached at eschultz@fresnobee.com or (916) 326-5541.