Flow measurement in various streams and channels is governed by various
principles of hydraulics and hydrodynamics and is known as hydrometry. The
hydrometry has been practiced since long in the country, and the status of the same
is discussed subsequently.
The surface flows are strongly affected by the precipitation phenomena and are
also random in nature in line with the precipitation. It becomes necessary to have
data lengths of appropriate lengths in order to arrive at a reasonable assessment of
the yield again based on stochastic concepts as well as on the basis of
hydro-meteorology of the basin. For the purpose of yield assessment, the volumes
that are available in a given interval of time become quite relevant, and assessment
of yields in intervals of week, 10 days, month or year is common. However, it is
required to be understood that the longer the time interval, the anomalies within the
intervals are levelled out, and any disaggregation of the data for planning at a
smaller interval is fraught with risks of failure.
2.3 Disaster Preparedness and Management
Water is not merely associated with beneficial uses but also is a cause of disasters
like floods and droughts. Especially, the floods which still occur regularly over the
large parts of eastern and north eastern India require management in real time for
generating advance warnings and putting relief measures in place.
Floods are primarily caused by the surface flows, and the occurrence is generally
confined to the monsoon period of the year. Measurement and assessment techniques require extensive surface water flows data in real time so as to make a
prediction about the eventuality of submergence and damage to land and people.
Rainfall and surface flows data collected in real time in key catchments and streams
provide most important measurements. While the yield assessment exercises require
the measurement frequencies of once in a day, the floods management in real time
often require measurements with frequencies of once an hour. Disaster management
also requires additional data in terms of topography, facilities and land use for
assessing the potential effects and also planning for the relief measures.
Data Usage for Development, Management of Water Resources
137
principles of hydraulics and hydrodynamics and is known as hydrometry. The
hydrometry has been practiced since long in the country, and the status of the same
is discussed subsequently.
The surface flows are strongly affected by the precipitation phenomena and are
also random in nature in line with the precipitation. It becomes necessary to have
data lengths of appropriate lengths in order to arrive at a reasonable assessment of
the yield again based on stochastic concepts as well as on the basis of
hydro-meteorology of the basin. For the purpose of yield assessment, the volumes
that are available in a given interval of time become quite relevant, and assessment
of yields in intervals of week, 10 days, month or year is common. However, it is
required to be understood that the longer the time interval, the anomalies within the
intervals are levelled out, and any disaggregation of the data for planning at a
smaller interval is fraught with risks of failure.
2.3 Disaster Preparedness and Management
Water is not merely associated with beneficial uses but also is a cause of disasters
like floods and droughts. Especially, the floods which still occur regularly over the
large parts of eastern and north eastern India require management in real time for
generating advance warnings and putting relief measures in place.
Floods are primarily caused by the surface flows, and the occurrence is generally
confined to the monsoon period of the year. Measurement and assessment techniques require extensive surface water flows data in real time so as to make a
prediction about the eventuality of submergence and damage to land and people.
Rainfall and surface flows data collected in real time in key catchments and streams
provide most important measurements. While the yield assessment exercises require
the measurement frequencies of once in a day, the floods management in real time
often require measurements with frequencies of once an hour. Disaster management
also requires additional data in terms of topography, facilities and land use for
assessing the potential effects and also planning for the relief measures.
Data Usage for Development, Management of Water Resources
137