Most of the early ventures and attempts at public private partnerships in the 1990's were either single project legislation or a limited number of "demonstration" projects.
For example, the Dulles Greenway legislation was enacted in 1988 for a single private road using a regulatory model. By that I mean, the private entity was to be established as a public utility and regulation of the tolls and rate of return were to be regulated as a utility by the State Corporation Commission (the Virginia equivalent of a public utilities commission).
In 1989, California AB680 authorized up to four projects in a franchise model, i.e., the construction phase was held by a franchise and then turned over to the state. The state then had the ability to lease each facility to the developers for up to 35 years.
In Washington State, five projects were authorized and proposals were submitted for many more than that. However, when the legislature changed parties, the bill was changed dramatically and sent all proposals back to the drawing boards. This undermined the private sector confidence in the Washington State model. (One project survived but not as originally envisioned).
Arizona enacted legislation in 1991 combining some of the Virginia utility model and some of California franchise model, It allowed for privately financed transportation facilities. Three projects were selected however never went to final financing. A final toll road project met with major local political opposition and in the end, it did not move forward.
Minnesota enacted legislation in 1993, however the project moving forward was vetoed by a locality.
All of this as a quick summary to demonstrate that the USA did not have a good track record in the public private partnership arena. And in Virginia, the 1994 the General Assembly enacted legislation that looked like the 1988 legislation (public utility model) for any number of projects. Governor George Allen asked that the legislation be rewritten so that it could be enacted in 1995, using a "market based" approach. The responsibility for the rewrite came directly to the Secretary of Transportation's office.