Dynamic Analysis of
Water Resources
Distribution in the
Wang Li
April 2006
Abstract
The vitality of all
life on Earth and our economic prosperity depend on fresh water. The maintenance
of a reliable fresh water supply will be one of the greatest challenges in the future
for our cities, agriculture and the well being of people throughout the world. Especially
in arid regions, the lack of fresh water resources has become a barrier to economic
and social development. Increasingly, conflicts occur between water users. Effective
water resources management is vital for these countries and regions. The management
of the response to water shortages depends heavily on good decisionmaking. Such
decision-making relies however, on accurate and reliable models.
The main objective of
the research described in this thesis is to build an integrated river model,
which consists of a flow routing sub-model, and sub-models for the abstraction water
from the river and the simulation of groundwater. The integrated model is
applied to water resources distribution in a drought-stricken river basin where
data are scarce, to assess the water resources distribution plans for such
river basins.
Three separate
sub-models operating at different time scales are integrated to generate the
water resources model. A key component of the model addresses flow routing
along the main river reach and is based on a solution of the simplified Saint
Venant equations. With a single assumption based on the water surface gradient
the Saint Venant equations reduce to a single equation in the discharge that
includes two parameters c0 (kinematic wave speed) and a0 (attenuation
parameter), which are non-linear functions of discharge Q. These parameters
describe the river geometry including the roughness of the channel. In
addition, they are peculiar to each river and independent of any flood event.
The other key sub-models are for water resources distribution and the simulation
of the groundwater. These sub-models are integrated with the flow routing
sub-model through the removal of water by the intakes from the river channel,
and the exchange of groundwater with the river.
The case study is
focused on the middle and lower
ecosystem degradation in the
lower basin has become more and more serious. Therefore, efficient water
resources distribution plans need to be established for the middle river basin
to ensure water supply to meet the demands of agriculture, industry and
domestic use, as well as satisfying
the needs of the ecology in the lower basin. The objective of the model is to
calculate the water volumes that can be reasonably extracted from every intake
along the middle