The New York City's Catskills programme is an example of a local-level public scheme (The Catskills/ Delaware Watershed Protection programme (New York) Stanton et al. For example, the nitrate strategy of Switzerland encourages farmers to enhance the environment of their farmland (UNECE, 2007, pp. Similar schemes also used to payforthe maintenance of forest areas and afforestation or reforestation to ensure high quality drinking water supply for municipalities, such as the canton of Basel (see Example 3).