Here is an article on Seeking Alpha that I would like to bring to your attention. Toll roads can be classify as an infrastructure asset that acts like a 30 year bond like stream of income.
Basically the company uses equity or debt cash to pay for operating a concession for 30 years, using the cash flow to pay back the interest, maintenance and dividends to the share holders.
Typically debt levels are high.
This article by Clemens Scholl goes into:
- How toll roads comes about, the history of it
- Where are the publicly listed toll roads around the world
- Summary of the toll roads and their financial data
- Different characteristics of the companies
Have to say that out of all the tolls, Bangkok Expressway listed on the thailand stock exchange looks interested with a debt to asset of nearly 45% and dividend yield of 7.1%.