Watershed management – objectives and approaches
of watershed management
12.1 Introduction
Soil, water and vegetation are the three important natural resources. As these
resources are interdependent there is a need to have a unit of management for most
effective and useful management of these resources. In this context, watershed is an
important unit for the management of the natural resources
12.2 Concept of watershed management
A watershed is defined as any spatial area from which runoff from
precipitation is collected and drained through a common point or outlet. In other
words, it is a land surface bounded by a divide, which contributes runoff to a
common point (Fig.12.1). It is defined as unit of area, which covers all the land, which
contributes runoff to a common point. It is synonymous with a drainage basin or
catchment area. The basic unit of development is a watershed, which is a manageable
hydrological unit. The watershed is also known as ridgeline in U.K.
Fig. 12.1 watershed with main and sub drains
As the entire process of Agricultural development depends on status of water
resources, watershed with distinct hydrological boundary is considered ideal for
planning developmental programmes. It is essential to have various developmental
programmes on watershed basis in conjunction with basic soil and water
conservation measures. The developmental activities need to be taken up from
ridgeline to outlet point (ridge to valley). Watershed management programme in
drylands aimed at optimizing the integrated use of land, water and vegetation in an
area for providing an answer to alleviate drought, moderate floods, prevent soil
erosion, improve water availability and increase food, fodder, fuel and fibre on
sustained basis.
Watershed management implies the wise use of soil and water resources
within a given geographical area so as to enable sustainable production and to
minimize floods.
Watershed management is the rational utilization of land and water
resources for optimum production with minimum hazard to natural resources.
Watershed management has been taken up under different programmes
launched by Government of India .The Drought Prone Area Development Programme
(DPAP) and the Desert Development Programme (DDP) adopted watershed
development approach in 1987. The Integrated Watershed Development Project
(IWDP) taken up by the National Wasteland Development Board (NWDB) in 1989
also aimed at development of wastelands on watershed basis. The fourth major
programme based on watershed concept is the National Watershed Development
Programme for Rainfed Areas (NWDPRA) under the ministry of Agriculture .The
ministry of Rural development funds watershed development schemes under DDP,
DPAP and IWDP.
Based on the size the watersheds may be classified as
Micro watersheds: The size of the watershed range from few hectares to hundreds
of hectares. These can be designed within the crop fields.
Small watersheds: The watershed has few thousands of hectares as drainage area.
Large watersheds: The river basins are considered as large watersheds.
12.3 Principles of watershed management
– Utilizing the land based on its capability
– Protecting the fertile top soil
– Minimizing the silting up of the reservoirs and lower fertile lands
– Protecting vegetative cover throughout the year
– Insitu conservation of rain water
– Safe diversion of surface runoff to storage structures through grassed
water ways
– Stabilization of gullies and construction of check dams for increasing
ground water recharge.
– Increasing cropping intensity through inter and sequence cropping.
– Alternate land use systems for efficient use of marginal lands
– Water harvesting for supplemental irrigation
– Ensuring sustainability of the ecosystem
– Maximizing farm income through agricultural related activities such as
dairy poultry, sheep, and goat farming
– Improving infrastructural facilities for storage transport and agricultural
marketing
– Setting up of small scale agro industries and
– Improving socio-economic status of farmers.
12.4 Objectives of watershed management
The term watershed management is synonymous with soil and water
conservation with the difference that emphasis is on flood protection and sediment
control besides maximizing crop production. The watershed aims ultimately at
improving standards of living of common people in the basin by increasing their
earning capacity, by offering facilities such as electricity, drinking water, irrigation
water, freedom from fear of floods, drought etc.,
The objectives are
– Recognition of watershed as a unit for development and efficient use of
land according to land capabilities
– Flood control through small multipurpose reservoirs and other water
storage structures at the headwater of streams and problem areas.
– Adequate water supply for domestic, agricultural and industrial needs
– Reduction of organic, inorganic and soil pollution
– Efficient use of natural resources for improving agriculture and allied
occupations so as to improve socio- economic conditions of the local
residents and
– Expansion of recreation facilities such as picnic and camping sites.
The objectives of watershed management programme can also be described in
symbolic form by the expression: POWER. Here the letters symbolize the following:
P = Production of food-fodder-fuel-fruit-fibre-fish-milk combined on
sustained basis
– Pollution control
– Prevention of floods
O= Over exploitation of resources to be minimized by controlling excessive
biotic interferences like over grazing
– Operational practicability of all on farm operations and follow
up programmes including easy approachability to different locations in
watershed
W = Water storage at convenient locations for different purposes
– Wild animal and indigenous plant life conservation at selected places
E = Erosion control
– Ecosystem safety
– Economic stability
– Employment generation
R = Recharge of ground water
– Reduction of drought hazards
– Reduction of siltation in multipurpose reservoirs
– Recreation
12.5 Action plan for watershed development (steps in watershed
management)
1. Identification and selection of watershed: The boundary of the watershed has
to be marked by field survey starting from the lowest point of the water course and
proceeding upwards to the ridge line. The area may vary as low as 100 ha to as high
as 10000 ha.
2. Description of watershed.
Basic information has to be collected on
Location
Area, shape and slope
Climate
Soil – geology, hydrology, physical, chemical and biological properties, erosion level
Vegetation-native and cultivated species
Land capability
Present land use pattern
Crop pattern, cropping system and management
Farming system adopted
Economics of farming
Man power resource
Socio economic data
Infrastructural and institutional facilities
3. Analysis of problems and identification of available solutions
4. Designing the technology components
a. Soil and moisture conservation measures
b. Run off collection, storage and recycling
c. Optimal land use and cropping system
d. Alternate land use system and farming system
e. Other land treatment measures
f. Development of livestock and other allied activities
g. Ground water recharge and augmentation
5. Preparation of base maps of watershed incorporating all features of geology,
hydrology, physiography, soil and proposed development measures for each part of
watershed.
6. Cost-benefit analysis to indicate estimated cost of each component activity, total
cost of project and expected benefit.
7. Fixing the time frame to show time of start, duration of project, time frame for
completion of each component activity along with the department / agency to be
involved in each component activity
8. Monitoring and evaluation to assess the progress of the project and to suggest
modification if any
9. On-farm research to identify solutions for site-specific problems.
10. Organizational requirement: Crucial component of watershed development
project is the organization. Land use problems can only be tackled in close
association with owners. As such local people should be involved in the project. To
promote such an interaction the size of watershed should be 300-500 ha at micro
level and a cluster of about 10 such watersheds could be managed by a single
organizational unit. Watershed development agency at unit level may be an ideal
organization for implementing the project. Since no project can be successful without
people’s participation, the watershed development agency should incorporate
selected representatives of the local people. The organizational requirement include
a. Water shed development agency with multidisciplinary staff
b. Training to personnel
c. Training to farmers
d. Credit institution
e. Farmers forum /village association
f. Non governmental organization