A new report from U.S. DOT Inspector General, “Financial Analysis of Transportation-Related Public-Private Partnerships,” says Public-Private Partnerships (PPPs) rarely generate “new” money.

PPPs “change the timing with which funds become available, but generally do not increase overall funding levels,” the report says, because investors who provide funds up front assume risk and expect to be rewarded with a profit over the length of an agreement.

The report examines financial disadvantages of PPPs over traditional public methods; identifies factors that help PPPs derive value; and assesses whether PPPs close the infrastructure funding gap.  The authors did not analyze the advantages of risk-sharing arrangements or the ability of the private sector to deliver a project more expeditiously.

(See a 28-page PDF of the DOT report here.)