The Tasman District Council is a unitary authority which combines the functions of both a city council and a regional council. The Tasman region has over 9,000 kilometres of rivers and streams and contains more than 80 lakes. These waterways provide valued places for swimming, boating and other recreation, a home for aquatic plants and animals, a source of food, water for drinking, hydroelectricity, and irrigation for horticulture and agriculture. This region is also home to Te Waikoropupu Springs, the largest cold water springs and some of the clearest water in the Southern Hemisphere.