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Water resources development and management
C. J. Jagadeesha
Scientist
Regional Remote Sensing Service Centre
Indian Space Research Organisation
Bangalore Tel: 6661003
Advantage of using
remote sensing data for hydrological modelling and monitoring is its ability to
generate information in spatial and temporal domain.
Remote Sensing
(RS) data and Geographical Information System (GIS) play a rapidly increasing
role in the field of hydrology and water resources development. Although very
few remotely sensed data can be applied in hydrology, such information is of
great value since many hydrologically relevent data can be derived from remote
sensing information. One of the greatest advantages of using RS data for
hydrological modelling and monitoring is its ability to generate information in
spatial and temporal domain, which is very crucial for successful model
analysis, prediction and validation. However, the use of RS technology involves
large amount of spatial data management and requires an efficient system to
handle such data. The GIS technology provides suitable alternatives for
efficient management of large and complex databases. Information from satellites
is becoming more and more important for environmental research; an important
part of this information concerns water - an element most essential for man, its
phases and peculiarities. If the Earth surface image are available, the
information obtained may be considered as a spatial model of a natural event.
The problem is to interpret the model, to measure its basic parameters, to
discover interrelations between the events and to determine changes introduced
to the environment. Particular problems correspond to the different spatial
scales. As for surface water problems, high resolution imagery from IRS series,
Landsat series and SPOT satellites provide basic information for the
parameterisation of conditions for different hydrological regimes and for water
resources evaluation.
Issues in water management
The
various identified issues in water resources development and management
situation in the country can be broadly classified as
- Surface water management issues.
- Ground water management issues.
- Integrated river basin
management issues, encompassing environmental issues and institutional issues.
Issues connected with surface water management are :
Theoretically, we have enough renewable water in our annual rainfall. However. considerable resourcefulness, innovative skill, lack of community participation and local involvement in design and management are required to use that water to meet our requirements.
- Attitude that water is the ‘basis of
life’ and is ‘beyond price’ - The lack of economic appraisal of
water projects ; downstream cost of upstream benefits,
internalisation, etc.
- Front end problem whereby the incentives
appear to be to build a "monument" and move on to another project
- Most planning is done incrementally and
is driven by the need to find solutions to relatively immediate
and specific problems, often requiring an unique institutional
framework.
- The issue of assurance is addressed in
the context of what are the institutional characteristics of the
successful projects else where.
- Water conservation by
controlling water loss, recycling & reuse, improving agriculture water use
by water control institutions.
Issues connected with ground water management are :
- Aquifer and draw down issues
- like depressed water table - interaction between shallow and deep aquifers
and imbalances between fresh water and salt water interfaces.
- Ground water support service
issues - technical performance of ground water utilisation in improving
command area, recovery of water charges; ownership issue of individual versus
group management and public versus private.
- Sustainability issues in
water surplus areas - like balancing surface water and ground water
development for optimal utilisation etc.,
- Sustainability issues in
water deficit areas - like planning for water conservation, water quality
management improved recharge, conjunctive use ; the progressive deepening of
wells (over - exploitation) over put small farmers at a disadvantage.
Issues in integrated river basin management
- Proper identification of
development objectives and their prioritisation with the technological choice
socio-economic milieu -regional level optimisation models using multi
objective approach providing scenarios for short listing and final selection.
- The concept of information
system (or infotech highway) which will have relevant hydrologic and
non-hydrologic data at appropriate resolution from a judicious mix of ground
and remote observations - i.e the concept of Natural Resources Accounting for
water.
- The sustainable water
development faces several obstacles like a) fragmented sector policies b) weak
or non-existent institutions and inadequate co-ordination among sector
agencies c) lack of adequately trained and motivated manpower d) use of
technologies inappropriate for developing country conditions e) lack of
community involvement f) problems of resource mobilisation and utilisation and
cost recovery etc.
- Representative issues in
water quality management including identifying levels of management viz
passive, active, proactive etc; availability of dilution water, costs of waste
treatment vs disposal, allocation of environmental costs and benefits for
biodiversity disturbance, submergence of forest, eutrophication etc.
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