Watershed:
An area that drains surplus rain or snow melt water.It is so because water holding capacity of the area is less than the amount of precipitation received.
• It is independent drainage unit for surface water runoff.
• One watershed is separated from other by natural boundaries known as the Water divide or Ridge line.
• It is independent drainage unit for surface water runoff.
• One watershed is separated from other by natural boundaries known as the Water divide or Ridge line.
Watershed line:
“ A line on the highest ground that separates two adjoining watersheds”.
Types of Watershed:
The types of watershed are classified on the basis of shape, size,drainage and land use pattern.
• Macro watershed (> 50,000 Ha)
• Sub-watershed (10,000 to 50,000 Ha)
• Milli-watershed (1000 to 10,000 Ha)
• Micro watershed (100 to 1000 Ha)
• Mini watershed (1-100 Ha)
Watershed Management:
“ Application of science for getting maximum yield of clean water on sustained basis or manipulation of hydrological cycle to serve the best interest of the dam”.
Objectives of watershed management:
• Get clean water
• Get maximum amount of water
• Get regular (sustained) flow of water
• To develop the productivity of watershed
• Pollution control
• Water storage,flood control,checking sedimentation
• Erosion control
• Recharging ground water
Distinct Features of Watershed Management:
It is generally said that watersheds are more difficult to manage than forest, range or crop lands. Let us examine the distinctive features of watersheds that make the above statement true.
Large Size:
• Watershed generally comprises very large tracts and are, therefore, unmanageable. The watershed of a specific stream or river may be extended over many districts,provinces or even adjoining countries.
• Many of watersheds are highly inaccessible and are without any roads or trails are very difficult to traverse.
Extremely Heterogeneous:
• Watersheds are highly variable in terms of climate, physigraphy, soil. vegetation, soil structure, social problems, local languages, civil administration and political system etc.
• This variation creates additional hurdles in the management of such areas.
Absence of LandOwner-ship by the Watershed Management Authority:
• The land in a watershed is generally owned by a large number of agencies and people; each owner having his own objective of management and distinctly different land use.
• The Watershed Manager is the only option of getting work done through persuasion, education and cooperation.
Place of activity always different from place receiving benefits:
• Watershed are the area where all management activities are concentrated,land use laws and restrictions are observed, sacrifice of varied nature are made.
• The area which receive most of the benefit of all above activities, effort and sacrifices are generally outside the watershed limits.
Principles of Watershed Management:
Watershed management is classified into seven broad groups or guidelines for the purpose of clean comprehension and easy understanding and for reference. These broad guidelines are called “Principles”.
The following are seven principles of Watershed Management
• Objective of Watershed Management
• Suitable administrative cum, research cum and field work organization
• Clear comprehension of the watershed area
• Conducting different types of surveys
• Vegetation/Biological operations( operation related to Forestry,Range,Wild lands,Farm lands,stream bank consolidation)
• Education and motivation of the people
• Engineering Operations.
