Alameda County voters will decide Nov. 6 whether to double their sales tax for transportation in a campaign being widely watched to gauge the public's appetite for paying more taxes for roads, freeways and public transit.

Passage of Measure B1 by a two-thirds majority would make Alameda the first county in Northern California to boost its transportation sales tax to 1 cent. The current rate is a half-cent.

The tax would become permanent, too, unlike two previous half-cent taxes on Alameda County measures that had sunset dates.

The extra money -- $7.8 billion over three decades -- would be used to fix potholes, make a $400 million down payment on a BART extension to Livermore, reduce congestion with improvements to Interstates 680, 580 and 880, and partially restore service cuts at AC Transit and for other public transit.

County leaders and several business, labor and environmental groups say the measure is essential to provide local help for a transportation system beleaguered by dwindling and unreliable state and federal aid.

"We need to take action to help ourselves or else our transportation system will decay as it has in many other counties," said Alameda County Supervisor Scott Haggerty of Dublin, a member of the 22-member commission that crafted the tax measure over two years. "This is local money the state cannot take away."

Critics say county leaders want too much in sales taxes, and that a regressive tax hits poor people the hardest.

The current tax rate in most Alameda County cities is 8.75 cents for $1 of taxable goods. Measure B1 would boost that rate to 9.25 cents.

Critics also say it's wrong to enact a tax that lasts forever. Even if economic conditions change, there is no requirement that the 1 cent tax be put back before voters for renewal.

"Why should the Alameda County Transportation Commission be given a blank check at taxpayers expense?" wrote Alameda County resident Estes Phillips, Christopher Pareja and Mary Steel in ballot arguments against Measure B1.

There has been little organized opposition to the measure.

County leaders assert it's folly to think the state or federal government will return to past levels of financial assistance for roads and public transit.

"It's a fantasy," said Mark Green, the Union City mayor and chairman of the Alameda County Transportation Commission, the agency that proposed the higher tax.

Yet the need for public transit and paratransit is growing as more baby boomers reach their golden years and pressure builds to reduce congestion and get cars off the road to reduce greenhouse gases, Green said.

Green and Haggerty said the higher and permanent sales tax is needed because roads, freeways, public transit systems need permanent attention and upkeep.

"You aren't going to plan to fund a police department for 15 years and then say, 'Let's just forget about it after that,'" Green said. "The proposition is an admission of the reality that transportation is not a one-time fix."

Some of the tax money would be used to secure state and federal grants, such as the $400 million in local taxes that BART hopes to use to secure larger grants for the BART-to-Livermore extension.

The sales tax would be divided up with 48 percent going to public transit and paratransit and 30 percent going to maintain streets and roads. The rest goes to projects for freeways, bicycling and pedestrian travel and encouraging compact development near transportation centers.

There would also be grant money for pilot projects with free transit passes for students.

Measure B1 supporters say there is public accountability and oversight over the tax spending.

A citizens watchdog group will annually review the tax spending. Also, voters countywide must approve a long-term list of transportation projects to be funded by the tax in 2042 and every 20 years afterward.

Contact Denis Cuff at 925-943-8267. Follow him at Twitter.com/deniscuff.

SPENDING PLAN FOR ALAMEDA COUNTY SALES TAX

Highlights of the spending plan for Measure B1, which would raise $7.8 billion over 30 years by doubling the transportation sales tax to 1 cent.
Public transit and paratransit: $3.7 billion, or 48 percent of total
Includes $400 million for BART to Livermore; $120 million for BART station at Irvington in Fremont; $120 million for Dumbarton Rail commuter service between East Bay and the Peninsula; $1.45 billion for AC Transit; $464 million for East Bay Paratransit Consortium; $100 million to modernize BART stations
Local streets and roads, $2.34 billion, or 30 percent
Includes $1.55 million in pass-through funds to cities and Alameda County to maintain roads; $800 million for improvements on major commuter corridors
Highway efficiency and freight: $677 million or 9 percent
Includes interchange and/or widening improvements along I-80, I-580, I-680, and Highway 84
Bicycle and pedestrian projects: $387 million or 8 percent.
Includes improving bike lanes and biking and hiking trails
Sustainable land use and transportation links: $300 million or 4 percent
Includes funds to plan, develop and provide infrastructure for housing or developments near transit stations or centers
Technology innovation: $77 million or 1 percent
Includes investments in technologies to decrease auto use, increase vehicle occupancy rates, manage parking or use clean vehicles

For details: Go to www.alamedactc.org and click on Learn More about the TEP (Transportation Expenditure plan.

Source: Alameda County Transportation Commission