"'This proposal sends the wrong signal, that additional sprawl development will be supported by Metro via emphasis on one person/one vehicle transportation,' says the statement, submitted to Metro by Brandt Mannchen, chairman of the chapter's Air Quality Committee.
Metro's HOV system carries about 100,000 riders a day, the agency estimates. Opening it to some toll payers could actually reduce exhaust emissions, said spokeswoman Raequel Roberts.
'It is better to move single-occupant vehicles into unused HOV lane space than to have them idling in traffic,' she said.
Roberts provided a graph from the Houston-Galveston Area Council on which carbon monoxide emissions per mile increase dramatically at speeds less than 10 mph. Nitrogen oxides and volatile organic compounds also increase, although less sharply."