What are Lakes?



There is no universal definition for a lake. The International Glossary of Hydrology (UNESCO and WMO 1992) briefly states, that a lake is an "inland body of water of considerable size". 

In the broadest sense, lakes, wetlands and reservoirs can be considered “standing water” systems.

In scientific terms, standing waters are termed “lentic” systems, whereas flowing waters (rivers) are known as “lotic” systems. 

• In general, because lakes usually have both inflowing and out flowing rivers, a lake basin can be characterized as a complex combination of both lentic and lotic waters, with this distinction between the two being of great importance for lake management . 

The EU Water Framework Directive, WFD (2000/60/EC) has defined a lake as a body of standing inland surface water. The Annex II of the WFD has in a way also determined also the minimum size of a lake, which should be taken into account to be 0.5 km2 (50 ha).




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