Mike Zdon is hardly a household name, but no one has played a bigger role these past eight years in shaping Napa County's transit and highway programs.

The consolidation of city bus systems, the design for the Highway 29/Trancas interchange, the failed half-cent transportation sales tax -- all were projects shaped by Zdon.

Zdon leaves his job Friday as executive director of the Napa County Transportation Planning Agency to look for new challenges. It is up to his successor to sell voters on a sales tax hike, he said.

Zdon, 60, arrived in 1998 when agency was taking form. Right off, he was charged with bringing together the many transit services from American Canyon to Calistoga.

Today, the agency runs them all, including the VINE and Vine Go paratransit, while helping the county and its five cities divvy up state and federal transportation funds and select highway projects for Caltrans.

Under Zdon, the agency became a model for how cities and the county could cooperate, said Napa County Supervisor Bill Dodd, until recently the transportation agency chair.

"He was able to balance all of the needs of all the cities and the county without anyone feeling he was favoring one over another," Dodd said. "He did it with such skill and class."

"He was really good for Napa," said Kathryn Winter, a former agency chair. "He's the consummate staffer to an elected official."

Napa Mayor Jill Techel echoed Winter. "We wanted someone who would take a brand new organization and give it meat and be successful," she said. "He's one of my favorites. He's great. I will miss him."

In an interview Tuesday, Zdon ticked off a handful of accomplishments during his eight years, but conceded his replacement will have a full plate of unresolved issues.

Number one is crafting a transportation plan, funded by an increased sales tax, that voters can support, ideally in 2008, he said. "The need for a local funding source -- that's the struggle for the agency," he said.

Napa is a rural county with urban traffic problems caused by commuters and tourists, Zdon said. Until local voters pass a transportation sales tax, congestion and pavement conditions will only get worse, he said.

Measure H, a proposed half-cent increase in sales tax to fund county transportation initiatives, was trounced in June because of high gas prices, national pessimism over the Iraq war and distrust of government, Zdon said. The voters' mood may be better in November 2008, a presidential election when turnout would be much greater, he said.

Zdon, who announced his retirement shortly before the Measure H election, said it could be helpful to have a new person work with city and county leaders to decide what happens next.

"A lot of this stuff takes creative thinking and energy," Zdon said. "It takes a fresh approach, not someone encumbered by eight years of history."

His successor will be paid more than $130,000, said Zdon, who earns $128,000 salary. The salary was increased to be competitive with what surrounding counties are paying, he said.

The executive director is in charge of an agency with a staff of eight and a budget of $10 million. State sales tax totaling $6 million pays for county transit services. Another $4 million in state and federal dollars pays for local roads and highway projects.

Zdon will recommend that his successor push to make the agency independent. The agency is a division of the county Public Works Department, but functions autonomously, Zdon said. A formal split would eliminate a potential conflict of interest, giving the agency greater credibility with the cities, he said.