Congestion pricing and the environment
Congestion pricing is an issue that taxpayer advocates and environmentalists can rally behind. Environmentalists in other states and countries have been advocating for congestion pricing, and it's only a matter of time before environmental groups in Utah catch up with their counterparts in other places.
Congestion pricing slows the growth in vehicle miles traveled by incentivizing car pooling, telecommuting, living closer to work, and leaving earlier/later. This is good for the environment due to reduced pollution and good for taxpayers because growth in transportation spending is reduced while congestion is reduced.
Congestion pricing will also shift discretionary non-commuting traffic to off-peak hours. According to the US Department of Transportation, up to 50% of rush-hour traffic is discretionary (that is, non-commuting) Even if discretionary traffic is merely shifted instead of reduced, this still reduces pollution because fewer drivers will be stuck for longer periods of congestion burning more fuel than if they were just able to drive at normal freeway speeds.
According to the Texas Transportation Institute's 2005 Urban Mobility Report, Americans waste more than 2.3 billion gallons of fuel per year due to congestion, and that's bad for our wallets and for the air we breath.