The test of Santa Rosa's first bike boulevard originally expected to take six months will now stretch to 10 as the city scrambles to find middle ground between warring factions.

The City Council has asked the Bicycle and Pedestrian Advisory Board to study two controversial traffic-reducing measures, which will postpone until May council consideration of the project's fate, said Transportation Planner Nancy Adams.

The delay arose over proposals to prohibit left turns from College Avenue onto Humboldt and to install a concrete diverter to block the intersection at Pacific Avenue to prevent traffic crossing from one side of Humboldt to the other.

Supporters say both approaches would make the street even more bicycle friendly, while neighborhood opponents told the City Council on Tuesday that the experiment is making it harder for them to use their cars.

A city traffic survey indicates the College Avenue prohibition would reduce the number of cars turning onto Humboldt during peak hours to around 40.

The Pacific Avenue diverter, which would impact traffic continuing north and southbound on Humboldt as well as those attempting to make left turns from Pacific onto Humboldt, would reduce traffic on Humboldt by more than 230 cars during peak afternoon hours.

Adams said the proposals should further reduce traffic on Humboldt by hundreds of additional cars a day while creating a less threatening environment for cyclists.

A survey in September of four sections of the roadway found vehicular traffic dropped from 2,887 to 2,333 cars daily compared to 2008 and the number of cyclists riding specific sections of Humboldt during the heaviest hours of use — morning, mid- and late-afternoon — rose from 385 to 485.

Adams said the two new proposals are efforts to make the 1.5-mile-long boulevard, which stretches from Lewis Road to Fifth Street, safer for cyclists.

The idea of a bike boulevard is to have a street that cyclists and motorists share equally.

The concept requires motorists and cyclists to follow each other in single file but allows drivers to pass bike riders when there is no oncoming traffic. To improve traffic flow, the raised dots that divided Humboldt into two lanes have been removed.

The test, which began in August, also includes temporary traffic circles installed at four intersections along the 15-block straightaway, the removal of many stop signs and installation of numerous signs to warn of the roadway's dual role.

The two proposals to test if the roadway can be made safer were widely assailed at Tuesday's council meeting by a dozen residents living in the area. They said it would force hundreds of motorists to take detours to reach their homes, pick up their children at school or patronize a Humboldt Street business.

"You're turning the neighborhood upside down for a minority," said Humboldt Street resident Diane Whitmire. She recently turned in 225 petition signatures from mostly area residents demanding the city put an end to the experiment they say has made the narrow street more dangerous to travel.

Another Humboldt Street resident, Kenneth Foster, accused the cycling community of trying to take control of Humboldt for themselves. "They don't want to share it. The bikers want us off the road."

Supporters including Christine Culver, executive director of the Sonoma County Bicycle Coalition, said the two proposals would be a "small inconvenience" to insure greater safety.

Culver said pushing forward with a bike boulevard, partly as an effort to reduce greenhouse gas emissions, is an important step.

"This is the first bike boulevard in all of Sonoma County and blogs are talking about this internationally," she said.

Steve Frye, a Humboldt Street resident, member of the bike advisory board and supporter of the project, said those on both sides "agree it's still not safe."

Frye said the College and Pacific avenue ideas should be tested to see if an increased level of safety can be achieved.

Traffic Engineer Jason Nutt said the project seemingly has an equal number of opponents as supporters making it difficult to move ahead with a consensus course of action.

"It all depends on who is showing up at what meeting," he said. "We think more needs to be done to have a complete test."

The continued debate clearly flustered the council, which directed the bike advisory board to review the two proposals and determine if there might be options that would be more acceptable to both sides.

"It doesn't seem to feel like we've gotten it quite right yet," said Mayor Susan Gorin.

Councilman Gary Wysocky, a co-founder of the bicycle coalition and resident of the area, supports moving ahead with at least the Pacific Avenue diverter.

"We're talking about a little bit of inconvenience for a lot of livability," he said.

Councilman John Sawyer, however, said adding new measures should wait.

"Accept the fact Humboldt will never be a perfect bike boulevard," he said. "Accept it as a success and stop the changes and let it rest for awhile to get the people there used to it."