investment in water and sanitation continues to be constrained by a lack of clarity over the assignment of regulatory powers across different levels of government. This has held back much-needed investment" (Dean, 2005). Overall, the water sector appears to be in a good position to strengthen its institutional foundations. However, recent construction projects to improve sewage treatment by building large new facilities in Porto Alegre, Greater Sao Paulo and other major conurbations have had problems due to financing and are proceeding in a "stop-start" manner. Elsewhere in South America the situation is similar, with virtually no sewage treatment in El Salvador and Paraguay and highest levels in Nicaragua and Brazil. Where treatment exists, system performance may be poor, unmonitored or badly regulated. Waterborne diseases are thus endemic in a number of countries, such as Colombia. Citing a review in 1991, UNEP (2002) reports that the major issues in Latin America are: poor political support for wastewater treatment, linked to lack of environmental policies; financing, including a lack of indigenous institutional capacity and the form of financial models imposed by international agencies; and the need for more appropriate technologies. Canada Canada's water resources are considerable. It has an estimated 7% of the world's renewable water supply, the third highest percentage after Brazil and Russia. Almost 9% of its land area is covered by freshwater, including some 25% of the world's wetlands. However, for a country of just over 31 million people in 2003 and with a per capita GDP of CAD 29 700 (putting it in the top 15 in the world), it is not without water problems. Some 85% of the population lives within 300 km of the southern border with the United States while 60% of the country's freshwater drains northwards. The amount of INFRASTRUCTURE TO 2030: TELECOM, LAND TRANSPORT, WATER AND ELECTRICITY - ISBN 92-64-02398-4 - © OECD 2006 5. THE IMPACTS OF CHANGE ON THE LONG-TERM FUTURE DEMAND FOR WATER SECTOR INFRAST