“In the last 25 years, light rail systems have been built in Baltimore, Buffalo, Dallas, Los Angeles, Pittsburgh, Portland, Sacramento, San Diego, San Jose and St. Louis. These rail systems were sold with promises that they would attract more riders than buses, reduce pollution, and ease congestion.

“Not even one of them has had any impact on either congestion or pullution. Typical ridership has been 50 to 60 percent below initial projections, and the total cost per rail passenger has been underestimated by 200 to 400 percent. Only in Houston, where planners choose to concentrate on road based solutions, has transit produced measurable improvement.”
Linda Gorman – Independence Institute

The real funny thing here is that Houston built one in spite of this.