A central premise behind a controversial proposal to add toll lanes to the I-405 freeway came under attack Tuesday evening as dozens of local residents and elected officials gathered to voice their steadfast opposition.

Officials at the forum in Westminster said the entire effort is being pushed by the state Department of Transportation or Caltrans, supposedly because of a new federal mandate to keep traffic flowing in carpool lanes used by low-emission vehicles.

But that “technicality” risks only about $12 million in funding, said Ron Casey of the Rossmoor Community Services District, while adding the toll lanes is expected to cost an extra $100 million.

“This is being done to us. It’s not being done with us,” County Supervisor John Moorlach said of Caltrans’ approach.

“It’s a power play by Caltrans,” said Westminster Councilwoman Diana Carey.

The proposal, known as “Alternative 3,” would create two toll lanes in each direction on I-405 between Seal Beach and Costa Mesa and add one general-purpose lane.

It’s one of three options set for a vote by the Orange County Transportation Authority board next Friday.

At least 16 elected officials came to the forum to show their opposition to toll lanes, representing the cities of Huntington Beach, Westminster, Costa Mesa, Fountain Valley, Los Alamitos and Seal Beach, and unincorporated Rossmoor.

Also attending was Assemblyman Allan Mansoor, R-Costa Mesa, and representatives of Rep. Alan Lowenthal, D-Garden Grove; state Sen. Lou Correa, D-Santa Ana; Sen. Mimi Walters, R-Irvine; and Assemblyman Travis Allen, R-Huntington Beach.

While OCTA and Caltrans were invited to the event, organizers say, they declined to participate.

Much of the frustration at the forum was directed at what many view as a “double tax.”

The new lanes would be paid for by Measure M2, the local officials said, which was approved by voters in 2006 without mentioning anything about toll roads.

“Toll lanes on top of those taxes was never part of the deal,” said Fountain Valley Councilman John Collins. Adding toll lanes would be an “insult” to voters, he said.

“This would be a tax on a tax on a tax,” said Huntington Beach Mayor Connie Boardman.

In a letter that was read aloud, Irvine Councilwoman Beth Krom declared she couldn’t think of anything that could damage OCTA’s credibility more than adding toll lanes.

“It is an absolute breach of faith with County residents who are on the hook until the year 2041 for an additional half cent in sales tax which would never have been supported if voters thought tolls would be introduced on our freeways,” Krom wrote.

Meanwhile, OCTA staff say that any toll lanes would funded not by taxes, but through bonds paid off by toll revenue.

Local chambers of commerce also showed up to voice concern that the toll lanes would hurt businesses.

Most of the car dealerships in the area are along Beach and Harbor boulevards, which wouldn’t have exits from the toll lanes, an official said.

Instead, the local officials are proposing “Alternative 2,” which would keep the current carpool lane as is and add two general-purpose lanes in each direction.

“Bottom line, you can move more cars and more traffic with free lanes than you can with the HOT [high occupancy toll]” lanes, said Costa Mesa Mayor Jim Righeimer.

OCTA officials expected such criticism at the meeting and pointed out that the board has yet to make its vote. They said a final decision on the project rests with Caltrans, which owns and operates the freeway system.

“While we certainly do take into consideration [comments from] the community directly next to the freeway, … it’s also important to look at it from a big-picture, regional transportation perspective,” said OCTA spokesman Joel Zlotnik.

Any excess toll revenues would go toward making improvements to freeways and public transit, he added.

“The people that choose to pay for the toll lanes actually end up benefiting everyone in the area with additional transportation improvements,” said Zlotnik.

Yet local electeds say they still don’t know where exactly the money would go.

“I’ve asked that question. I’ve never seen a clear” answer,” said Collins.

In light of the fact that each of the proposed I-405 widening options would cost more than $1 billion, other meeting attendees suggested that policymakers need to start devising more creative options for reducing traffic. “Just expanding the freeway is not going to cut it,” said a Costa Mesa resident.

Another resident suggested running buses along the existing carpool lanes as a type of rapid-transit system, with vans then shuttling commuters from transit stops to their workplace.

OCTA officials, meanwhile, point out that I-405 is the busiest freeway in the country and that meeting its traffic needs would require doubling its capacity.

The local officials called on residents to become involved and express their displeasure regarding the toll lane option to OCTA board members and Gov. Jerry Brown’s office.

Rossmoor resident Nia Hartman also created an online petition on the issue that has attracted more than 700 supporters.

OCTA’s Regional Planning and Highways Committee is set to make a recommendation next week to the full board. The committee meets Nov. 4 at 10:30 a.m. at OCTA headquarters, 550 S. Main Street in Orange.

The full board meeting is Nov. 8 at 9 a.m.

Update: This story has been updated to reflect OCTA staff’s explanation that the toll lanes would only be funded through toll revenue.

You can reach Nick Gerda at ngerda@gmail.com, and follow him on Twitter: @nicholasgerda.

Join the conversation: In lieu of comments, we encourage readers to engage with us across a variety of mediums. Join our Facebook discussion. Message us via our website or staff page. Send us a secure tip. Share your thoughts in a community opinion piece.