Car-pool lanes waste valuable space on freeways.

Laudably, California car-pool lanes now accept hybrids and other fuel-efficient cars to reduce the loss.

Planners are discussing whether to open car-pool lanes to all between peak travel periods, but just the opposite is needed because experience shows more drivers use restricted lanes during peak periods.

Experience with extensive car-pool lanes in Los Angeles and Orange Counties shows more than a 10 percent loss in the number of vehicles that are moved compared with free-flow on all lanes as in San Diego County.

High Occupancy Toll lanes permitting single-occupant cars have been tried on Interstate 15 in San Diego in an attempt to compensate. Tolls for the single-occupant vehicles based upon demand indeed keep traffic flowing in these special lanes.

But there is a net loss to the whole freeway from their underuse.

Contrary to all this evidence, planners including the San Diego Association of Governments want to expand these HOT or "managed" lanes. Applied to about 90 percent of badly needed freeway expansion, they would cost about $7 billion. Why add to the complexity and segregate vehicles when a 10 percent penalty results?

Other advocates argue that tolls will be used for more roads, thus compensating for gas tax reductions as cars get more efficient. But unfairly, only 7 percent of I-15 users pay tolls. Hybrids will diminish this further.

Contrary to intentions, all tolls now and under the 40-year TransNet plan will go to build and subsidize transit projects that few people use. Consider the bus that runs now on I-15: It carries only 200 commuters out of more than 50,000 who are using the freeway during peak periods.

Competent planners have shown how intelligent, computer-operated ramp meters can let all lanes operate at maximum capacity. No need for Mickey Mouse toll collections and law enforcement attention to car-pool lanes. A bonus is less local street congestion because freeway onramp waits are less.

Many leaders still think the people attracted to the car-pool lanes compensate for bigger losses in capacity elsewhere in the transportation system.

Adding freeway lanes is the most cost-effective way to fight congestion. But we should not waste money on complexities that actually reduce their performance.

Former North County resident Walt Brewer is a frequent commentator on local transportation policy.