Lynne Kiesling offers a lengthy discussion of water privatization, with useful links. I have long thought that water is one of the tough cases for market economics. It is hard to imagine having two sets of pipes built to your home and thus it is difficult to see how competition would operate. Even Milton Friedman, to the best of my knowledge, never came out for laissez-faire for water. An obvious option is to have the pipes regulated, but allow competing carriers within a single piping network. You then have to regulate access to the piping network, and regulate the pricing of that access. Furthermore you must make sure that some institution has sufficient incentive to maintain the value of the piping network, comparable issues have proven problematic in the case of electricity. Managed competition may prove a better form of regulation than municipal ownership, or a vertically integrated natural monopoly, but it is regulation nonetheless. And unlike with electricity, it is hard to see decentralized provision of water becoming the norm anytime in the near future. Electricity offers options such as batteries, solar power, and private generators. Water without pipes is simply hard to live with, get ready to carry buckets on your head.
Nonetheless a good case can be made for the private provision of water, with unregulated pricing, in very poor developing countries, such as much of Africa. Let any private supplier sell water at any price the market will bear. Yes this sounds drastic, but the harsh reality is that otherwise many Africans have no access to piped water in the first place. Even a monopoly price is better than carrying that bucket on your head, and don’t forget that well water can cost ten or twenty times the price of piped water. I recall once reading that if the cure for AIDS were a simple glass of clean water, many Africans still would have no chance.
The problem remains that charging for water is problematic in many developing countries. Property rights are poorly defined and people are not used to paying for municipal services. If you set up water piping to the very poor and tried to collect fees in return, many people simply would not pay and legal recourse would be unclear. What can you do, report them to a credit bureau? Attach their wages? You can see the problems. Right now we know that progress in the water sector will be slow at best.