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CHAPTER 2
LITERATURE REVIEW
2.1 Introduction
Increasing demands for water by competing users in semiarid regions pose new
challenge for water resources managers. Decision makers must understand the
interactions between surface water, groundwater and environmental system.
Additionally, the decisions made with regard to water transfer and allocation must take
into consideration the diverse objectives that include water supply, cost efficiency and
ecosystem protection. The literature review presented here includes various aspects of
the water resources development and management in canal irrigated areas.
Hydrological studies in irrigation command area includes study of the rainfall
patterns, estimation of crop evapotranspiration, impacts of water logging and soil
salinity, cropping pattern and agro-climatic conditions. In canal command area
conjunctive use of surface and groundwater resources is essential for sustainable
agricultural development. A conjunctive use policy is termed stable when the policy
results in a negligible change in the ground water storage over a normal year. The work
done by different researchers in the area of conjunctive water use is reviewed in this
chapter at length.
The spatial and temporal variations of groundwater levels in canal irrigated areas
are high, with few observation points in large area. Geostatistics based methods,
particularly Kriging, is considered as one of the robust methods in regional studies. The
geostatistical approach have been used by many researchers to generate groundwater
surfaces and other aquifer parameters like hydraulic conductivity, transmissivity etc.
Some of the studies are presented here in brief.
For the effective development and management of groundwater of a basin, it is
essential that a careful water balance study shall be carried out. A variety of studies have
been reported which dealt with the groundwater modeling to understand the subsurface
flow system and groundwater balance under different natural and man induced stresses.
The scarcity of water and the competition for freshwater demand from domestic,
industrial, navigational and recreational uses are also increasing and thus the share of
water in the irrigation sector is bound to reduce drastically. The management of water in
irrigation sector must be taken up on priority basis. The database management
capabilities of GIS have the potential to expedite the collection of information from
geographically diverse sources. The spatio-temporal attribute of water use data are
ideally suited for analysis using a GIS approach. The literature reported in the last two
decades indicates that the water resources planning and management problems can be
well addressed using GIS.
2.2 Hydrological Studies in Irrigation Command Area
Molden and Gates (1990) developed the performance measures that facilitate analysis of
irrigation‐water delivery systems in terms of adequacy, efficiency, dependability, and
equity of water delivery. The measures provide a quantitative assessment not only of
overall system performance, but also of contributions to performance from the structural
and management components of the system. The performance measures can be
incorporated in an irrigation system monitoring program and can provide a framework
for assessing system improvement alternatives. The usefulness of the measures in system
evaluation was discussed with the example applications to systems typical of Sri Lanka
and Egypt.
A less planned growth of irrigation intensity by canal systems, tube wells and
other schemes have led to undesirable effects of water logging, especially in the alluvial
regions of India. Serious repercussions of these effects involve loss of cultivable land,
reduction in the crop yield and contamination of aquifers. Sreenivas et al. (1992)
examined certain aspects of water logging problems in MRBC Command Area in central
Gujarat, India. The major causes for water logging are poor sub-soil drainage,
over/excess irrigation and the proposed measures are properly lining of canal, improved
drainage system and conjunctive water use.
Poor drainage and return flow from excess irrigation, along with continuous
seepage from canals is certainly responsible for the rising trend of water table and hence,
water-logging conditions in the command areas. The quantity of water being added to the
subsurface storage is required so that a conjunctive water management scheme involving
adequate ground water withdrawals may be used to control the rising trends. Rastogi and
Prasad (1992) carried out numerical (FEM) modeling to investigate seepage losses from
Nadiad branch canal in MRBC command area of Kheda district in Gujarat, India.
Water table depth, piezometric head, and precipitation were measured by Beke et
al. (1993) at nine sites in southern Alberta over a period of 28 years to determine the
effect of irrigation on long‐term groundwater levels. Irrigation and precipitation directly
recharge the unconfined aquifer. High water tables are most frequent during May–July,
when irrigation water is applied and precipitation is high. Highest levels generally
occurred in soils with glacial till at depths less than 1.50 m from the surface. It was
concluded that as increasing water table levels predominated at sites with till within 1.50
m of the surface, special management schemes need to be developed for these soils.
Gutwein and Lang (1993) carried out the study of irrigation water demand at the
field level and checked whether field‐level estimates can be applied to predict the water
usage of a region. They used the crop and water‐use data for a 30‐year time period to
analyze a 200,000 ha desert region in southern California. They attempted to correlate
water usage with crop acreage and climatic variables were using the Blaney‐Criddle
evapotranspiration method, but showed limited success.
Yamashita and Walker (1994) used the cumulative water demand (CWD) curve
to validate and calibrate the Unit Command Area (UCA) model, which predicts the
aggregate water demands of individual command areas for the entire crop season. The
logistic function with three parameters, namely management‐allowable depletion,
irrigation application uniformity, and initial soil moisture, was adopted for fitting the
CWD curve. High correlations were observed between the individual curve parameters
and the field variables. Effectiveness of the equation developed for a particular UCA
using the regression analysis was successfully demonstrated.
The ASCE Task Committee on Defining Irrigation Efficiency and Uniformity has
provided a comprehensive examination of various performance indices such as irrigation
efficiency, application efficiency, irrigation sagacity, distribution uniformity, and others.
Consistency is provided among different irrigation methods and different scales. Burt et
al. (1997) provided the clarification of common points of confusion and proposed the
methods whereby the accuracy of numerical values of the performance indicators can be
assessed.
Goyal and Chawla (1997) presented the solution for estimation of seepage from a
canal to symmetrically placed drainages founded on infinite pervious soil medium with
uniform infiltration from the free surface zone. They obtained the integral equations
using Zhukovsky's function and the Schwarz-Christoffel transformation and solved them
numerically to obtain the seepage losses. The problem was analysed for different
parameter values such as canal width, infiltration rate, the distance between the canal and
drainages. The effect of different parameters on the seepage discharge and the free
surface profile were presented in form of graphs and Nomographs were prepared for the
evaluation of canal seepages.
Sen (1998) suggested a percentage weighting (PW) method as an alternative to
the Thiessen polygon method to calculate the average areal precipitation (AAP) over a
catchment area. The basis of the method is to divide the catchment area into subareas by
considering the rainfall percentages considered at three adjacent station locations. The
method was found more reliable and flexible than the Thiessen polygon method where
the subareas remain the same independent of the recorded rainfall. In PW method, higher
precipitation values are attached with smaller subareas. It was observed that the PW
method yield relatively smaller error of estimate as compared to the other available
methods.
Ambast et al. (2000) presented a methodology to estimate the regional
evapotranspiration (RET). The methodology was based on surface energy balancing and
utilizes the digital data in visible and infrared region along with the ancillary
meteorological data to derive various fluxes involved in the computation. The FAO
Penman Monteith was selected as the standard method for comparison to evaluate the
other temperature based methods. The study revealed that among the different
temperature based methods, the Blaney-Criddle method gave estimate of RET closest to
the FAO Penman Monteith method.
Irrigation scheduling deals with two questions: when and how much to irrigate.
When adequate water supply is assured, irrigation can be scheduled to saturate the crop
root zone depth up to the field capacity and the timing of irrigation may be estimated by
the time it takes for the soil moisture to deplete to the critical level. Such an irrigation
schedule ensures that the crop will grow at its potential rate provided all other
agricultural inputs are supplied at optimal levels. Optimal resources allocation strategies
for a canal command in the semiarid region of Punjab, India were developed by Paul et
al. (2000) in a stochastic regime, considering the competition of the crops in a season,
both for irrigation water and area of cultivation. The proposed strategies were divided
into two modules using a multilevel approach. The first module determines the optimal
seasonal allocation of water as well as optimal cropping pattern. The stochastic dynamic
programming algorithm was used to determine the expected values at various risk levels.
The second module was a single crop stochastic dynamic programming intra-seasonal
model that took the output of the first module and gave the weekly irrigation allocation
for each crop by considering the stress sensitivity factors of crops.
The estimation of RET is of great importance for agricultural, hydrological,
atmospheric circulation and climatic change detection models. The estimation of ET at
regional scale in currently used models is based on point source information pertaining to
meteorological data. This is mainly due to difficulty involved in measuring it over a large
diverse areas or lack of spatial information to estimate it. Remote Sensing offers a
potential means of measuring outgoing fluxes, surface temperature and leaf area index.
Ambast et al. (2002) presented a methodology to estimate RET. The methodology is
based on surface energy balancing and utilizes the digital data in visible and infrared
region along with the ancillary meteorological data to derive various fluxes involved in
the computation. The developed methodology was utilized to estimate RET using
Landsat-TM data for a part of the Western Yamuna Canal (WYC) command in the state
of Haryana, India. The described methodology was found computationally stable and can
be used in practice for most real life applications without sacrificing much accuracy.
Arora and Goyal (2002) carried out a systematic study for the factors responsible
for water-logging and soil salinity in Hanumangarh and Sri-Ganganagar districts of
Rajasthan, India. They incorporated various meteorological, geological, hydrological and
environmental characteristics of the study area to arrive at the causes of water-logging
and soil salinity. It was concluded that a comprehensive socio-economic survey of the
affected villages shall be carried out for the assessment of the impact of water-logging.
They suggested that, incorporating the remote sensing data for the area, a mathematical
model may be developed to understand the environmental impacts of water-logging and
soil salinity.
Water and energy are two important resources for human development and have
inextricable inter-linkages between them. Gupta (2002) analyzed the demand-supply
situation of both sectors for Gujarat state and found the overexploitation of groundwater
in some parts of the state and also, the worsening water quality. The serious impact on
energy balance is due to the fact that more than 40% energy is consumed for extracting
groundwater. The feasible options available to meet the crisis i.e. development of mega
projects like Sardar Sarovar Project and Kalpsar project and micro water harvesting
structures, water pricing, consumer training etc. were reviewed by him.
Multi temporal remote sensing data based crop inventory, generation of
vegetation spectral index profiles and ETc estimation were carried out in MRBC
command area, Gujarat by Ray et al. (2002). Distributary-wise performance indices,
namely adequacy index, equity index and water use efficiency index, were computed. It
was found that water availability was in excess along main canal and branch canals
whereas it was less and crop condition was poor towards the tail ends of the command
area. The authors concluded that the integration of RS data and GIS tools to regularly
compute performance indices could provide irrigation managers with the means for
managing efficiently the irrigation system.
Suratgrah branch is a major canal system of Indira Gandhi Nahar Pariyojana
(IGNP). Water table in the Suratgrah branch command area is continuously rising,
causing more and more area covered under water logging. Water logging not only
results in depleted fresh water resources but also causes salinisation, health hazards,
ground water contamination and adverse environmental effects. Keeping in mind the
serious ill-effects of water logging, a socio-economic survey was conducted by Chahar
and Choudhary (2003) in six chaks in water logged command area of Suratgrah branch
canal of IGNP. The survey revealed that the income of the farmers increased after the
commencement of the canal, it reached to a maximum and then started to decline due to
water logging. Water logging in the study area may have resulted mainly due to seepage
from canals, return flow from irrigated fields and lack of natural drainage.
Sustainability relates to both physical as well as socioeconomic environment.
IGNP command area of Hanumangrah and Sriganganagar districts in Rajasthan are
facing problems of water logging and salinity. The ill-effects of water logging have not
only led to loss of agricultural land and properties, but also have resulted in
environmental degradation and change in socioeconomic pattern of affected households.
Arora et al. (2005) carried out the socioeconomic survey of the affected villages in the
study area. It was concluded that the social cost of water logging and salinity is much
more than the cost of submerged and degraded land and agriculture.
Gujarat, in western India is not endowed with plentiful of water resources. The
present utilization of water in North Gujarat already exceeds the assessed potential. The
assumption in present strategy of water resource development is that the technologies are
well known and/or are sufficiently developed and what is required is essentially a proper
management of the system. It is however felt that in addition to conventional remedies
suggested, there is a strong need for innovative technological solutions for the various
hydrology related problems of the state. Gupta and Deshpande (2005) identified some of
the specific areas of research that need to be pursued in the immediate future and
suggested the research strategies.
Basin and inter-basin transfers of surface waters through major irrigation
networks and easy availability of tube well technology converted arid and semi-arid
regions of India into intensive agricultural areas. Farmers adopted new cropping patterns,
which include the water-loving crops such as rice and sugarcane over traditional crops
like pearl millet, maize, pulses and oil seeds. Adoption of intensive irrigated agriculture
without planned irrigation development disturbs the regional water and salt balances in
some parts. A one-dimensional water and solute transport UNSATCHEM model was
calibrated and validated by Kaledhonkar and Keshari (2006) with a saline water use
experiment for wheat and cotton crops. The model was further employed for regional
scale salinity modeling with distributed data on soil, irrigation water supply and its
quality from six locations in the Kheri command of the Bhakra irrigation system.
Guidelines for sustainable conjunctive water use planning were prepared for Kheri
command to get optimum agricultural production despite the use of saline water for
irrigation under prevailing scenarios of water availability and its quality.
Mohan and Sangeeta (2006) tested different infiltration models based on the soil
type and land use variations for the estimation of the groundwater recharge in a basin.
Green Ampt model, Modified Kostiakov model and Horton model were found to be fit to
the observed data to estimate infiltration rates and their parameters were determined
using least square method. The infiltration results were compared with standard Soil and
Water Assessment Tool (SWAT) model. It was concluded that Horton model is the most
appropriate infiltration model for estimating recharge in the study area.
Periodic monitoring of Agro climate of a given location is essential to verify the
apprehensions of the climate change affecting agro ecosystem. Roorkee is agriculturally
advanced revenue subdivision of Haridwar District in Uttarakhand state in India. A study
was taken up to assess the Agro climate variability of Roorkee by Tripathi et al. (2007).
The weather data was statistically analysed for standard deviation and coefficient of
variability. Reference crop evapotranspiration (ET0) was calculated using FAO
CROPWAT. The Agro climate was classified using Moisture Availability Index (MAI)
as recommended by Thornthwaite and Mather and it was found that Roorkee fall in Dry
Sub Humid class.
Kaledhonkar and Keshari (2007) employed models dealing with water and solute
transport under variably saturated conditions for regional scale modeling to understand
irrigation induced salinization processes in the command of Kheri distributory of Bhakra
irrigation system. The CROPWAT software was used to estimate ET values of the crops.
Considering the crop area and canal supplies, pumping of water was estimated.
Interpretations based on regional water balance and distributed modeling was used to
assess the sustainability of the prevalent conjunctive use policy of utilizing poor quality
ground water along with canal water. Ambast et al. (2008) presented a remote sensing
based procedure to estimate the sensible heat flux incorporating the local meteorological
conditions and in turn to determine the regional evapotranspiration. The model utilized
satellite-derived surface albedo, surface temperature, and leaf area index along with a
very few agro-meteorological data as inputs. The procedure was tested on a part of the
Western Yamuna Canal system, India, and was found to be computationally simple and
stable. Results revealed that the percentage change in mean sensible heat flux for the
image was less than 5% in all cases, thus indicating the acceptability of the model
against the uncertainties. The model was also applied to three sets of Landsat-TM data
covering the Sone Low Level Canal system, India, to demonstrate its usefulness in
evaluating water delivery performance.
Monitoring changes in wetland vegetation is a useful tool for detecting changes
to groundwater hydrology, as vegetation is a basic ecosystem feature able to reflect the
state of vitality and maturity of the system. Serrano et al. (2008) observed the changes in
hydrology in 6 temporary ponds in the Do-nana National Park, Huelva (Spain) over 17
years by recording the fluctuation of their shallow water table and the duration of their
wet phase during each hydrological cycle. The changes in vegetation cover and
distribution were also quantified using aerial photographs. The water table oscillations
were analyzed in relation to rainfall variability and groundwater extraction, and it was
shown that both pond hydro-period and plant community changes were useful tools for
monitoring hydrological changes.
Dhar and Datta (2010) developed a methodology based on an optimization model
solution for the design of groundwater quality monitoring network. Redundancy
reduction is an important issue in the optimal design of a monitoring network. The model
incorporated the inverse distance weighting method for spatial interpolation of
concentration data. The formulated logic-based mixed-integer linear optimization model
was solved using the branch-and-bound algorithm. Performance of the proposed
methodology was evaluated for different scenarios using available historical
concentration data. The results demonstrated the potential applicability of the proposed
methodology for groundwater contaminant monitoring network design, while
incorporating reduction in redundancy of monitoring locations.
Prats and Pico (2010) presented the study of the performance and uncertainty
associated with an irrigation scheduling method based on a soil-water balance. A Monte
Carlo simulation of the irrigation scheduling model was developed using a series of
actual daily weather data of evapotranspiration and precipitation. Performance evaluation
measurements and their uncertainty were studied by means of several parameters. Total
Available Water (TAW) is the most important hydraulic property of the soil as far as
irrigation scheduling performance is concerned. The statistical relationship between
evaluation performance measures and TAW was calculated. Soils with high values of
TAW perform better. It was found that the root zone depth and fraction of TAW that can
be depleted from the root zone before moisture stress are two variables that directly
affect the TAW.
Irrigated agriculture faces serious threats of water-logging and soil salinization in
the arid and semiarid regions. An integrated spatial-agro-hydro-salinity model
(SAHYSMOD) was used by Singh and Panda (2012) to analyze water and salt balances
of an irrigated semiarid area located in the Haryana State of India. The sensitivity
analysis revealed that hydraulic conductivity is the most sensitive model parameter for
both groundwater levels and salinities, followed by effective porosity of the aquifer. The
results showed a good agreement between the simulated and observed groundwater
levels and salinities during the calibration and validation periods.
Fischer et al. (2013) analyzed the hydrological long-term dry and wet periods for
the Xijiang River basin in South China. They evaluated the impact of long-term
precipitation pattern on the discharge of the Xijiang River. At a 24-month timescale, the
standardized precipitation index (SPI-24) for the six sub-basins of the River and the
standardized discharge index (SDI-24) for Gaoyao station were applied. The monthly
values of the SPI-24 averaged for the Xijiang River basin was found to correlate highly
with the monthly values of the SDI-24. It was concluded that the discharge of the Xijiang
River (SDI-24) is a direct response to the area weighted SPI-24 of the entire Xijiang
River basin. Hence, changes in precipitation are directly responsible for changes in
discharge.
American Society of Civil Engineers–Environmental and Water Resources
Institute had recommended the ASCE-EWRI Penman-Monteith (ASCE PM)
combination equation by as the standard equation for estimating ET0. The standardized
model was intended to simplify and clarify the presentation and application of the
method; however, it requires numerous inputs that frequently are not available at most
weather stations. Rojas and Sheffield (2013) provided the comparisons between
daily ET0 estimates from five different approaches using limited data to those computed
with the ASCE PM equation. The results revealed that the differences
between ET0 obtained with complete and limited data were influenced by the underlying
surface, the weather conditions during the study, and the application of empirical
methods to determine missing inputs.
2.3 Conjunctive Use of Water
The need for more efficient management of available water resources is gaining
increased recognition, particularly in regions where industrial, residential or agricultural
expansion causes present and future water demands exceed the natural supply. A
common characteristic of most regions is a space and time imbalance in water demands
and natural supplies. It is very common that the period of lowest natural water supplies
coincides with largest demand and vice versa. Any region deficient in surface water
supplies may be underlain by excessive groundwater reserves. Aron and Scott (1971)
stressed on the need and advantages of conjunctive operation of ground water and
surface water resources. They applied the technique of dynamic programming to the
study area for the purpose of developing an optimal policy of water-resources operation
to meet a given forecast demand.
In river basins where aquifers are intimately associated with streams, the
unrestricted development of groundwater can reduce stream-flows and jeopardize the
rights to the flow of surface water. A simulation model to aid in the solution of such
problems was developed by Young and Bredehoeft (1972). The model composed of (i) a
hydrologic model that represents the physical response of the stream-aquifer system to
changes in river flows, diversions and pumping, and treats stream-flow as a stochastic
input and (ii) an economic model that represents the response of irrigation water users to
variations in water supply and cost. These elements were incorporated into a decision
framework so that the net income to the water resource system associated with
alternative management schemes could be measured.
A complex problem of optimal conjunctive use of groundwater and surface water
resources was handled by Yu and Haimes (1974) by developing a general systems
analysis approach. A two-dimensional asymmetrical grid network model was chosen to
represent the aquifer system. A water resources management problem was considered for
a hypothetical region that was composed of several adjoining sub-regions over a
common aquifer basin. It was suggested that the regional water authority regulate
optimally the inter-sub-regional aquifer boundary conditions and impose a pumping tax
on the local water agencies of the sub-regions. The pumping tax would provide revenue
for the regional authority to recharge the aquifer basin.
Haimes and Dreizin (1977) developed a methodology for solving the problems of
conjunctive use of a large-scale complex ground water system, a network of streams, and
reservoirs all interacting with one another. Decomposing the model of a large-scale
aquifer system as well as that of a stream network into interacting sub-models provided
an improved mathematical model of the entire physical stream. A theorem was proved
that establishes the necessary condition for the existence of a solution to the optimal
control problem associated with the management of the groundwater system. A sample
problem was formulated in which the option of groundwater operations and surface
water supply are conjunctively utilized to meet the water needs of several water users in
a basin. The management problem was solved via decomposition and multilevel
approach.
Kashyap and Chandra (1982) developed a mathematical model for arriving at an
optimal conjunctive use policy incorporating (i) spatially and temporally distributed
ground water withdrawal for a predefined pattern of surface water availability and (ii)
spatially distributed cropping patterns. The groundwater withdrawals are constrained by
the need to keep the water table elevations over the entire area within an appropriate
range. The monthly ground water withdrawals and areas under seven feasible crops were
estimated for each zone by nonlinear programming.
Conjunctive use of surface water and ground water can usually increase yields at
lower costs than more dams and reservoirs operated separately. Implementation is more
difficult in countries where surface water development has historically dominated water
supply project formulation. Coe (1990) discussed the various constraints and advantages
of conjunctive use implementations and operations in the areas in California that have
experienced basin overdraft and increasing water demands.
In India, future demands for water cannot be met entirely from new surface
reservoirs and maximum groundwater development can only be obtained by conjunctive
use of groundwater and surface water reservoirs. Murty (1990) identified the
characteristics of conjunctive use systems and detailed the principles of planning based
on the past experiences for guidance in the actual planning process. He observed that for
conjunctive use practice, the planning process does not really envisage the
complementary use of surface and ground water systems.
Onta et al. (1991) used a three-step modeling approach for comprehensive
analysis of the planning problem involving integrated use of surface and groundwater in
irrigation. In the first step, a stochastic dynamic programming model was used to derive
the long-term operation policy guidelines for alternative plans. A lumped simulation
model was then used to evaluate the alternative plans and policies, considering a number
of mutually related synthetic sequences of stream flows and rainfall. Finally, a multi-
criteria decision-making method (compromise programming) was used to select the most
satisfactory alternative plan for indicating the system design capacities and water
allocation policies.
A conjunctive-use model was developed by Latif and James (1991) to maximize
water user’s return under limited and dynamic water supply for long-term conditions.
The main objective of the study was to find the optimal groundwater extraction for
stabilizing the water table at specific depths below land surface, while at the same time
supplementing the surface irrigation supply. Concepts of limited and stressed irrigation
were used to maximize net return.
A conjunctive use management model was presented by Matsukawa et al. (1992)
to develop planning and operational strategies for the Mad river basin in Northern
California. Operational constraints included hydropower production limits, water-quality
constraints on the blended surface water and ground water used to meet the municipal
demand, and minimum in-stream flow needs downstream of the water-supply abstraction
point. The optimization model was solved using MINOS, a large-scale non-linear
programming algorithm.
In conjunctive use of groundwater and surface water of a river system the main
points to be considered are (i) the availability of groundwater, (ii) the scope for recharge
and (iii) the quality of groundwater. In Krishna Delta, there is enough scope for
utilization of groundwater for agricultural purpose, subject to the quality considerations.
Viswanadh and Reddy (1994) examined the water quality in different regions of Krishna
Delta to adopt a suitable mix of groundwater and surface water in their conjunctive use.
The groundwater and surface water samples were collected and examined under different
canal systems of Krishna Delta and an appropriate average mix of groundwater and
surface water of 28:72 was suggested. Working tables were prepared for Nagarjuna
Sagar reservoir with mean monthly inflows with and without groundwater utilization in
Krishna Delta ayacutt. It was found that 751.7 Mm3 of surface water can be conserved at
Nagarjuna Sagar reservoir with this policy.
Panda et al. (1996) developed three nonstructural management models and linked
together to aid in planning the optimum allocation of land and water resources to achieve
the objective of maximizing return in the command area of a canal distributor. A
groundwater simulation model simulated water table depths, the seasonal crop water
response model computed crop yields and inter seasonal irrigation system planning
model maximized net annual return through conjunctive use of surface and gypsum-
treated sodic ground water to achieve an optimal cropping pattern using LP algorithm.
The LP model was operated at five different mixing proportions of surface and poor
quality groundwater and seven probabilities of exceedence levels where rainfall, canal
water supply and crop water requirements were assumed supply.
Mohan and Jothiprakash (2000) formulated fuzzy linear programming (FLP)
model to derive optimal crop plans for an irrigation systems with the aim of conjunctive
utilization of water from surface reservoir and ground water aquifer. Considering the
fuzziness involved in the input variables such as inflows and ground water pumpage, the
FLP model maximizes the degree of satisfaction or truthness subject to objective
function, physical and economic constraints. It was found that the fuzziness in the
ground water pumpage plays a prominent role in deriving the optimal operational
strategies.
The irrigation water requirements of major crops and the total available water
through canal and groundwater in the command of Shahi distributory were estimated by
Singh et al. (2001). A linear programming model was formulated to suggest the optimal
cropping pattern giving the maximum net return at different water availability levels. The
model gave the optimal cropping pattern for a command area of 11818 ha at water
availability levels of 100%, 70% and 50%. It was found that the water available in the
command area may support optimally 4981, 3560, 1817, 632, 355, 87 and 3653 ha of
wheat, sugarcane, mustard, lentil, potato, chick pea and paddy crops, respectively, to get
a maximum net return of Rs. 185 million at 100% water availability. Wheat appeared to
provide most consistent profit in the command area.
Alluvial valley stream-aquifer systems are important sources of water supply in
many hydro-geologic regions and along many major river systems. Under natural
conditions, the aquifer is recharged by precipitation on the valley, groundwater moving
from adjacent aquifers, over-bank flooding, and infiltration from tributary streams.
Commonly, nearly all of the water pumped from these aquifers is derived from stream
flow depletion by the processes of captured groundwater discharge and induced
infiltration. Stream flow depletion by wells has become an environmental issue because
of the adverse effects that reductions in stream flow can have on aquatic and riparian
ecosystems. Barlow et al. (2003) developed conjunctive management models that couple
numerical simulation with linear optimization to evaluate trade-offs between
groundwater withdrawals and stream flow depletions for alluvial valley stream-aquifer
systems. They used the model to assess the effect of inter annual hydrologic variability
on minimum monthly stream flow requirements. It was found that increase in current
withdrawal from the aquifer by as much as 50% was possible by modifying the
withdrawal schedules, modifying the number and configuration of the wells in the supply
well network.
Jehangir et al. (2003) assessed the on-farm financial gains for paddy growing
farms through different models of irrigation and compared them with conjunctive use of
surface and groundwater. The problem of increased use of tube well water in the saline
groundwater zones that had resulted in the deterioration of the soils and groundwater
quality was highlighted. The SWAGMAN Farm Model had been used to evaluate the
financial and environmental trade-offs for effective conjunctive water management in the
Rechna Doab, Pakistan. The optimization results showed that it was possible to increase
the total gross margins while keeping the salinity levels and changes in depth to water
table in the acceptable limits through conjunctive water management.
Mohan and Jothiprakash (2003) noted that the conjunctive use of surface water
and ground water was practiced more by accident than by deliberate planning. They
found that no significant work have been carried out on applications of the conjunctive
use model for optimal water resources management in the context of controlling water-
logging in irrigation command area. A combined optimization-simulation approach was
used to develop and evaluate the alternate priority-based policies for operation of surface
and ground water systems. Three alternate priority-based policies differing in level of
ground water pumping and area of cultivation of rice crop were evaluated: (i) Irrigation
with surface water only, (ii) Irrigation with conjunctive use of surface and ground water,
without socio-economic constraints and (iii) Irrigation with conjunctive use operation
and with socio-economic constraints.
Karamouz et al. (2004) discussed a systematic approach to surface and
groundwater resources modeling in the Tehran metropolitan area. A dynamic
programming optimization model was developed for conjunctive use planning, with
objective function to supply the agricultural water demands, to reduce pumping costs and
to control groundwater table fluctuations. The mathematical model developed has the
flexibility to model different conditions and assumptions and can be used for future
planning and operation of water resources in the complex aquifer region.
Management of water resources in coastal and deltaic regions irrigated by the
river schemes involves primarily two issues: First, availability of water resources in
space and time, and second, seawater intrusion. Improper management arising out of
excessive irrigation or increased groundwater exploitation often leads to water-logging
or seawater intrusion problems, respectively. Any conjunctive use model must address
these two issues for application to coastal and deltaic regions. Rao et al. (2004)
developed a regional conjunctive use model for a near-real deltaic aquifer system,
irrigated from a diversion system with reference to hydro climatic conditions prevalent in
the east coastal delta of India. Surface water availability showed temporal fluctuations in
terms of floods and draughts and groundwater availability in terms of quality and
quantity due to hydro geologic setting, boundary conditions and aquifer properties. The
combined simulation-optimization model proposed in the study was solved as a
nonlinear problem using a simulated annealing algorithm and a sharp interface model.
In saline groundwater areas, optimal beneficial use of water resources can be
obtained by the conjunctive use. Optimal allocation of land and water resources to
different crops plays an important role for maximizing the net returns from the irrigated
area. The allocation of these precious resources is usually made based on applied water-
yield relationships of different crops. However, in saline groundwater areas, average
salinity of applied water-yield relationships of these crops should also be taken into
account. Srinivasulu and Satyanarayana (2005) developed a linear Programming model
for allocation of land and water resources to different crop activities in canal irrigated
saline groundwater areas. The model was run by LINDO software for maximizing the
net return. It was applied for irrigation water management at Agricultural College Farm,
Bapatla, India.
Vedula et al. (2005) developed a mathematical model to arrive at an optimal
conjunctive use policy for irrigation of multiple crops in a reservoir-canal-aquifer
system. The integration of the reservoir operation for canal release, groundwater
pumping and crop water allocation during different periods of crop season was achieved
through the objective of maximizing the sum of relative yields of crops over a year
considering three sets of constraints: mass balance at the reservoir, soil moisture balance
for individual crops and governing equations for groundwater flow. The conjunctive use
model was formulated with these constraints linked together by appropriate additional
constraints as a deterministic linear programming model. The applicability of the model
was demonstrated through a case study of an existing reservoir command area in
Chitradurga district, Karnataka, India. A conjunctive use policy was defined by
specifying the ratio of the annual allocation of surface water to that of groundwater
pumping at the crop level for the entire irrigated area.
Shortages of surface water supplies necessitate development of groundwater in
many commands. Khare et al. (2006) explored the potential and feasibility of conjunctive
use planning for Krishna-Pennar link canal. A simple economic engineering optimization
model was presented to explore the potential of conjunctive use of surface and
groundwater resources using linear programming with various hydrological and
management constraints and to arrive at an optimal cropping pattern for optimal use of
water resources for maximization of net benefits. The LINDO 6.1 optimization package
was used to arrive at optimal allocation plan of surface water and groundwater. The
results substantiated that conjunctive use planning is beneficial and feasible for the
proposed canal command.
As a non-structural measure to rapid drawdown of groundwater table in coastal
Balsor district in Orissa, India, Sethi et al. (2006) developed the deterministic linear
programming (DLP) and chance-constrained linear programming (CCLP) models to
allocate available land and water resources optimally on seasonal basis so as to maximize
the net annual return. They considered net irrigation requirement of crops as stochastic
variable. The quantitative system for business (QSB) software was used to solve the
models. Sensitivity analysis of the models was carried out by varying cropping scenarios
and combinations of surface water and ground water at various risk levels. The study
revealed that 40% deviation of the existing cropping pattern with conjunctive use of 20%
surface water availability and 30% ground water availability were optimal.
Jha and Singh (2008) focused on methodology for developing optimal allocation
of resources like land, crop and water of Kosi Irrigation System in Nepal. The system is
characterized by adequate water supply and distribution facilities with less utilization of
its resources due to lack of proper planning. A multi-objective model for irrigation
development was presented with integrated use of surface and ground water resources.
Alternative plans for irrigation development were identified by analyzing trade-offs
among the specified objectives of maximizing total net economic returns from
agriculture (economic efficiency), nutrition requirements of the area (health) and total
irrigated cropped area (balanced regional development) by using Goal programming.
In canal command area conjunctive use of surface and groundwater resources is
essential for sustainable agricultural development. A linear programming model was
formulated for the left Dadupur and its associated distributories and minors in
Bulandshahar district of Uttar Pradesh State, India by Mane et al (2010). The attempt
regarding the temporal conjunctive water use plan was demonstrated successfully in
terms of feasible solutions to the optimization problems for various scenarios.
Marques et al. (2010) applied the two stage stochastic quadratic programming to
optimize conjunctive use operations of groundwater pumping and artificial recharge with
farmer’s expected revenue and cropping decisions. The two-stage programming
approach allowed the modeling of water and permanent crop production decisions, with
recourse for uncertain conditions of hydrology and annual crops. The evaluation if the
results indicated potential gains in expected net benefits and reduction in income
variability from conjunctive use, with increase in high value permanent crops along with
more efficient irrigation technology.
Optimal crop planning and the conjunctive use of surface water and groundwater
resources are imperative for the sustainable management of water resources, especially in
semiarid regions. In recent years, considerable attention has been given to crop planning
and water resources management under uncertainties caused by climate changes that
affect irrigation planning. Safavi and Alijanian (2011) developed an optimal crop
planning and conjunctive use of surface water and groundwater for the Najafabad Plain,
in west-central Iran. The objective function of the optimization model was to minimize
shortages in supply of irrigation demands. The fuzzy inference system was used to
account for the experience and expert judgments of decision makers and farmers to
obtain optimal crop planning with a reliable water demand based on climate conditions.
Devi et al. (2012) carried out a study in Parambikula-Aliyar-Palar (PAP) basin,
Coimbatore, India where the command area is divided in two zones which receive the
canal supply in alternate years. The water demand and available water resources were
evaluated considering surface water, ground water and rainfall. The aquifer response and
recharge due to rainfall in PAP basin were examined. The efficiency of canal water
delivery system in a distributary was evaluated and the conjunctive use of available
water resources and its optimal allocation were arrived using an optimization model. The
model simulation resulted in a cropping pattern for the optimal utilization of the
available water resources.
Raul et al. (2012) developed an Irrigation Scheduling Model (ISM) and a Linear
programming Optimization Model (LPM) under hydrologic uncertainty with a view to
effectively manage the available land and water resources of the canal command. The
crop yield obtained by the ISM under different irrigation management strategies was
used in the LPM to optimize the land and water resources of the canal command. It was
found that the most beneficial crops with comparatively lower water requirements, like
pulses and vegetables, should be given priority, and the present practice of extensive rice
cultivation should be limited to minimum possible extent for sustainable protection
against global warming.
2.4 Geostatistical Analysis
Groundwater level and groundwater quality as well as quantity parameters can be
considered as regionalized variables with spatial distributional structures. The theory of
regionalized variables accounts for both the local randomness of variables as well as
their spatial structure. Semivariogram acts as summary information of all available
information on the structure of the variability of the phenomena at the site.
Semivariogram is a key function upon which the application of a branch of the
geostatistics is based. Various researchers have used different geostatistical methods in
their studies in the areas of groundwater, estimation of ET and rainfall, locations of the
rain gauge stations and monitoring wells, contaminant transport etc.
Smith (1981) checked the spatial variability of hydraulic conductivity in
predictive analysis of mass transport using kriging. A stochastic simulation of mass
transport was carried out using Monte Carlo simulation. Kriged estimates were
generated for the blocks in which hydraulic conductivity was not known. The results
showed that the spatial variation in hydraulic conductivity play a critical role in
controlling the contaminant transport in groundwater flow systems. The uncertainties
would have been better controlled if the measurement points were located along
pathways followed by contaminants.
Bastin et al. (1984) used statistical approach to the real time estimation of the
average rainfall over a catchment area of two river basins in Belgium. The average real
rainfall was computed by kriging using simple power function to fit the experimental
variogrm. The procedure also yielded a simple method for selection of the most
informative rain gauge amongst a set of existing ones and for selection of an optimal
location to install additional rain gauge stations. The work has a great significance in the
design of all types of monitoring networks.
The comparative study of spatial interpolation techniques was reported by Tabios
et al. (1985). The study area of about 52000 sq. km. consisted of 29 rain gauge stations in
north central Continental United States. The methods which were analyzed include
Thiessen polygon, the classical polynomial interpolation by least squares and the
Lagrange approach, the inverse distance technique, optimal interpolation and kriging
technique. The methods were compared in relation to estimating the annual precipitation
at five selected sites. Considering the various performance criteria, results indicated that
kriging and optimal interpolation techniques are the best among all other techniques.
Russo et al. (1987) examined the uncertainty of the estimation of correlation
scales of stationary fields using kriging. The study was carried out by generating
rehabilitation of a set of two dimensional isotropic second order stationarity function
with a given correlation scale. The results from 100 independent realizations showed that
the uncertainty about variogram values decreases as the number of sample points
increases. The coarser grid size results in the overestimation of the correlation scale.
Reasonable estimate could be obtained when the minimum distance between the
sampling points was smaller than half the range of the underlying process.
Texture analysis is a basic step in soil classification. Springer et al. (1987)
applied semivariogram and kriging algorithm for predicting hydraulic properties from
texture. The study compared the predicted hydraulic parameters from texture with field
measured ones. The field data for analysis was collected over a single field season on
agriculture field in north Utah. The parameters of the fitted exponential theoretical
semivariogram were identified using kriging in conjunction with the point suppression
method.
Cokriging could be a powerful tool to estimate water table in hilly terrain.
Hoeksma (1989) estimated water table elevation at unsampled locations with a water
table and ground elevation data measured at wells and points along flow streams using
cokriging. The exponential function was fitted to the experimental semivariogram and
validity of the fitted model was done by the cross validation method.
The concept of cumulative semivariogram could be useful to model
semivariogram when standard conditions of decreasing semivariogrems are not seen to
be valid. Subyani and Sen (1989) applied semivariogram approach in modeling and
mapping of hydrological parameters of Wasia aquifer in Saudi Arabia. When values of
variables were irregularly distributed and where data were scarce, inconsistency
increased and it was highly unreliable to fit non decreasing curve. It was found that
cumulative semivariogram possesses all the objective properties of classical
semivariogram. Gaussian model was fitted to the cumulative semivariograms and kriging
was used to estimate the variables at the locations other than the measurement points.
The krigged maps of transmissivity, storativity, porosity, TDS, piezometric level and
groundwater velocity were prepared.
Thangrajan and Shakeel (1989) applied universal kriging to estimate the water
levels in Vaippar basin in Southern India. More hypothetical locations were selected to
reduce the estimated variance near the boundaries. A bivariate interpolation technique
and the intrinsic random function of higher order were applied to compare the results.
Gaussian model was fitted to the experimental variogram. It was confirmed that
universal kriging using directional semivariograms could give better results to estimate
water levels. The kriging technique performed better than other two interpolation
techniques.
ASCE Task committee report on geostatistical techniques (ASCE, 1990a &
1990b) provide an extensive review of geostatistical applications in the area of civil
engineering. The report contains the basic concepts of geostatistics, characterization of
spatial variability of natural phenomena by semivariogram approach and various kriging
methods such as kriging, ordinary kriging, universal kriging, disjunctive kriging,
indicator kriging etc. It has reviewed the usefulness of geostatistical techniques in
mapping groundwater variables, conditional and unconditional simulation of geophysical
fields and local sampling design and geostatistical groundwater studies. The report has
also, explored the application areas as parameter uncertainty in ground water
management models. The concise report is very useful starting point for research work in
the field of geostatistics.
The semivariogram approach was applied by Shafer (1990) to characterize spatial
correlation for seasonal nitrate-nitrogen concentration in shallow groundwater in
northern Illinois. Monte Carlo simulation approach was used to verify the accuracy and
validity of the estimation. The confidence limits on sample variograms from different
time periods were used to evaluate the significance of temporal change in spatial
correlation. The average variations for spring and fall nitrate concentration appeared very
similar to visual inspection. It was concluded that the Jack-knife method of variogram
estimation resulting in calculation of confidence limits could be used as a part of
groundwater monitoring programs so that the sampling well network remains optimum.
McKinney and Loucks (1992) developed a network design algorithm for
improving the reliability of ground water simulation model predictions, using a network
design example. Kriging was used in first order uncertainty analysis to estimate model
parameters. The algorithm was to minimize the simulation model prediction variance by
choice of new locations for measurement of aquifer properties. It was found that
significant increase in the reliability of simulation model prediction could be achieved
measuring aquifer properties at locations selected by algorithm. The selection of
measurement locations was found to be greatly influenced by the type and extent of
boundary conditions existing in the aquifer.
To develop quantitative description of unsaturated water flow in spatially
variable porous materials, White and Sully (1992) used the semivariogram approach. A
grazed pasture area at the centre for environment mechanics field station, Prickle farm,
Bungenlore, New South Wales was chosen for the study. The soil at the site was loamy
sand. An exponential semivariogram was found to fit for porous material parameter. The
autocorrelation function revealed that autocorrelation was significant at the 90% level
only because of the small number of measurements. It was felt that the use of a single
parameter i.e. porous parameter was inadequate to describe the hydraulic conductivity.
A study was aimed to develop a set of appropriate models for point area rainfall
estimation in South Florida. Abtew et al. (1993) examined six methods to interpolate
point rainfall data and integrate area rainfall. Spatial correlation and variogram functions
were developed for study area using monthly rainfall data from 25 rain gauge stations.
The semivariogram was found best fitting to an exponential model. Mean, variance,
standard error, maximum absolute error and coefficient of determination were used to
compare the performance of various interpolation methods. The multi-quadratic
interpolation, kriging and optimal interpolation were found better methods for rainfall
interpolation.
Desbarats (1993) reported geostatistical analysis of steady state flow between an
injection well and a pumping well in a heterogeneous aquifer. A geostatistical conceptual
model for inter-well flow was obtained combining the deterministic spatial averaging
law for inter-well transmissivity with stochastic model for point-scale transmissivities. It
was reported that results may also be useful in the interpolation of the inter-well flow and
tracer tests for relating observations to statistical parameters of the transmissivity field.
Jemaa (1994) examined a multivariate approach based on the geostatistical
method of cokriging for the design of groundwater monitoring network. The
methodology was applied to a case study to design an optimal network to observe
transmissivity and specific capacity in California. The observations of the existing
sampling sites were used for estimation of variogram and cross variogram models
wherein the spherical model was best fitting. To generalize optimality, the branch and
bound algorithm with simultaneous search technique was used. The results were
compared with univariate kriging and it was reported that multivariate approach
improved the design by obtaining lower variance estimation.
The impact of various types of activities at the soil surface on the spatial
distribution of pore structure needs to be investigated. Such investigations, when
successful, could perhaps lead to predictions of modifications in hydraulic conductivity
due to various activities. Mohanty et al. (1994) used semivariogram approach to
determine spatial variability of surface hydraulic properties. The intrinsic and extrinsic
factors which contribute to spatial structure under different field conditions for
infiltration and runoff processes were differentiated. Infiltration rates were measured in
corn rows, no track inter rows and wheel track inter rows using automated disc
infiltrometer at the Agronomy and Agriculture Engineering Research Center near Boone
in Central Iowa.
Chang and Teoh (1995) selected thirteen wells in the Scioto river basin in Ohio to
study characteristics of groundwater droughts using kriging. Groundwater drought events
were derived by taking a truncation level through the time series of the daily
groundwater depths recorded as elevation difference between the water table and land
surface at a well site. Droughts of various levels were obtained. Conditional probabilities
from one level of drought to the next higher severity level estimated at all thirteen well
locations were treated as regionalized variable. Distances and directions were computed
between pairs of data for the semivariogram analysis and modeling. Cross validation of
the spatial estimator was conducted to check its capacity to represent spatial variability
and the validated estimator was used to obtain the regional estimates and their associated
errors. The estimator errors varied depending on the location and increased where data
points were sparse.
Assessment of rainfall is a key input in the planning of water resources projects.
Where the spatial variability of rainfall is quite high, event based and temporally
aggregated assessment is highly dependent on the location of rain gauge stations.
Rajaram and Gelhar (1995) examined the kriging theory to study spatial rainfall patterns
in basins of Japan for optimal selection of rain gauge stations. Three basins were selected
and heavy rainfall events were used to determine pattern of variogram. Power function
was fitted to the experimental variograms. Kriging was used to calculate variance at all
stations including hypothetical points. Points with minimum variance were selected as
rain gauge stations and the rainfall was estimated by the identified kriging model on the
basis of variogram.
Govindaraju et al. (1996) used semivariogram approach to determine the spatial
variability of soil hydraulic properties that governed infiltration. To understand the
influence of tillage operations on infiltration and surface runoff properties, the nature of
spatial variability of surface infiltration properties at two sites was investigated and
compared. It was found that variogram at the one site (agricultural site) differ from the
other site (plain site) in a distinct manner. The variogram for infiltration properties at the
agriculture site could be represented by spline function to bring out the periodic nature of
the soil infiltration properties. It was concluded that the spatial variability of the
infiltration properties have range of order of two to three meter over plain site while six
meter range would adequately represent the variability of the field study.
The use of variogram in the study of hydraulic head and the specific discharge
fluctuations was reported by Lent and Kitandis (1996). For the variogram analysis of
hydraulic head, Monte Carlo simulations tended to a much higher sill, indicative of the
higher overall total variance. A qualitative comparison of the variogram of the specific
discharge fluctuation perpendicular to the direction of flow from the Monte Carlo
simulations and Perturbation approximation were illustrated. It was concluded that the
large scale components of the transverse components of the specific discharge were not
correctly predictable by the small perturbation approximation, particularly for large scale
components of variability transverse to the direction of the flow.
Design of optimal networks in monitoring of contaminant transport is an
important area in environmental monitoring and geostatistics can be advantageously used
in this context. Mackey et al. (1996) demonstrated the use of geostatistics in the
probabilistic risk assessment of the potential hazards arising from the burial of waste
repository in Bedfordshire, U.K. The spatial structure of hydraulic conductivity was
characterized by variogram modeling by fitting a spherical variogram assuming zero
variance at the origin. Simulation of the pattern of contaminant migration was performed
using Monte Carlo experimental design involving geostatistical simulation of the
hydraulic properties principal conducting formation at the site. A sampling technique for
the quantification of uncertainty in the spatial and temporal distribution of the escapes of
contaminant to the biosphere was proposed.
The irregularity of sampling in space and the fact that groundwater levels exhibit
substantial variability with topography, make spatial estimation more difficult. Patel and
Remadevi (1996) used Kriging algorithm for spatial estimation of groundwater levels in
Thasara, Nadiad and Borsad regions in MRBC command area. The results showed that
the there exist a strong spatial correlation among different groundwater level
observations in the study area. It was found that Kriging gives better quality estimates in
comparison to other widely accepted methods and has the additional advantage in giving
the error variance at a point.
Different statistical approaches were examined for interpolating climatic data
over large regions of Maxico by Hartkamp et al. (1999). The paper provided a brief
introduction to interpolation techniques for climate variables of use in agricultural
research. Three approaches namely, Inverse distance weighted averaging, Thin plate
smoothing splines and Co-kriging, were evaluated for a 20,000 km2 area. Taking into
account valued error prediction, data assumptions, and computational simplicity, use of
thin-plate smoothing splines was recommend for interpolation of climate variables.
Dhiman and Keshari (2002) presented a methodology that utilizes GIS to
quantify the spatial geologic data and statistical analysis to determine the relation
between groundwater quality parameters and geological units. The areal extents of
geologic units in the study area in Western Indian Aquifer system were identified and
their spatial distributions were quantified using GIS. The spatial extents of identified
geological units were then correlated with the groundwater quality parameters using
statistical analysis. It was concluded that the study within GIS environment helps in
better understanding of the water-rock interactions and will prove useful in formulating
numerical models to study transport mechanisms of various chemical species in different
hydro-geologic and chemical environments.
The sustainable management of groundwater resources needs quantitative
information on its behavior in space and time. The spatial information of groundwater
levels at a grid pattern is necessary to obtain reliable results. Kumar and Remadevi
(2003) applied Kriging to incorporate spatial structure of the parameter and achieve
accuracy in estimation. Experimental semivariogram was constructed from the data
points in IGNP command area in Rajasthan and spherical, exponential and Gaussian
models were fitted to it. The Gaussian model which gave the minimum standard error
was used to finally develop the groundwater table contour map. The map was compared
with the similar map prepared using inverse square distance method. The results
suggested that Kriged map provide more regular gradient of groundwater table than the
inverse square distance method.
Asefa et al. (2004) presented a Support Vector Machines based methodology for
designing long-term groundwater head monitoring networks in order to reduce spatial
redundancy. It makes use of a uniquely solvable quadratic optimization problem that
minimizes the bound on generalized risk, rather than just the mean square error of
differences between measured and predicted groundwater head values. The nature of the
optimization problem results in sparse approximation of the function defining the
potentiometric surface that was utilized to select the number and locations of long-term
monitoring wells and guide future data collection efforts, which is a prerequisite in
building and calibrating regional flow and transport models.
Costa et al. (2008) presented a geostatistical analysis to provide an insight of the
geographic distribution of extreme precipitation events in the Southern region of
continental Portugal, as a basis for a future study of the relationships between extreme
rainfall patterns, both spatial and temporal, and desertification processes. They selected
three indices of extreme precipitation for an exploratory analysis: one index representing
dry conditions, another one representing extremely heavy precipitation events and
another index representing flood events. For each of these three indices, annual trends
and decadal space-time patterns were investigated. Ordinary Kriging was used to
estimate in space and time extreme precipitation indices and exponential model was
chosen that capture the major spatial features of each attribute under study by
subjectively fitting the model to the experimental semi-variogram values. The
geostatistical study concluded that the spatial patterns are more continuous in the last
decade than the other ones before.
Chatterjee and Purohit (2009) used the groundwater resources estimation
methodology1997 to estimatet the dynamic groundwater resourcesof India. They used
the water-level fluctuation technique and the norms for the recharge estimation. Based on
the stage of groundwater development and long-term water level trend, the assessment
units were categorised. The overall stage of groundwater development was calculated as
58% and about 70% of the assessmentunits were found in ‘safe’ category while the rest
fall under ‘semi-critical’ and ‘critical’ category. It was found that the over-exploitation
ofgroundwater prevails in northwestern, western and Penensular India: and eastern India
posseses good potential for future groundwater development. It was concluded that re-
assessment of groundwater resources at regular intervals is necessary because of the
changing groundwater scenario.
Eldeiry and Garcia (2010) conducted a study to compare Ordinary Kriging (OK),
Regression Kriging (RK) and CoKriging (CoK) techniques in an area in the southern part
of the Arkansas River Basin in Colorado. Six LANDSAT images in conjunction with
field data were used to estimate soil salinity. OK, RK and CoK were applied to 2,914 soil
salinity data points collected in alfalfa, cantaloupe, corn, and wheat fields in conjunction
with the selected LANDSAT image band combination subsets. The results showed that
the best band combinations for estimating soil salinity with different crops are as
follows: alfalfa [red, near infrared, and normalized difference vegetation index (NDVI)];
cantaloupe (blue and green); corn (near, thermal, and NDVI); and wheat (blue and
thermal).
Eldeiry and Garcia (2011) presented a practical method to manage soil salinity
and yield in order to obtain maximum economic benefits. The method was applied to a
study area located in the southeastern part of the Arkansas River Basin in Colorado
where soil salinity is a problem in some areas. Soil salinity data were collected in the
fields using an EM-38 and the location of each soil salinity sample point was determined
using GPS. Different scenarios of crops and salinity levels were evaluated. Indicator
Kriging (IK) was applied to each scenario to generate maps that show the expected
percent yield potential areas and the corresponding zones of uncertainty for each of the
different classes. The results showed that IK can be used to generate guidance maps that
divide each field into areas of expected percent yield potential based on soil salinity
thresholds for different crops.
Disjunctive kriging (DK) is a nonlinear geostatistical model that provides
unbiased estimates of the conditional probability (CP) that the true value of the property
of interest does not exceed a defined threshold. It has important implications in aiding
management decisions by providing growers with a quantitative input that can be used
for evaluating the variability of the crop productivity at different zones in fields.
Eldeiry and Garcia (2012a) applied the DK technique to data from a project conducted in
the southeastern part of the Arkansas River Basin in Colorado to generate CP maps and
to evaluate the expected Yield Potential Percentage (YP%). The results of the study
showed that the CP maps generated by using the DK technique give an accurate
characterization and quantification of the different zones of the fields. On knowing the
YP% of different areas, a management decision action can be undertaken to manage the
productivity of a field by selecting another crop or adjusting inputs.
The performance of Ordinary Kriging (OK) is impacted by different factors that
characterize the data sets being interpolated. Eldeiry and Garcia (2012b) evaluated the
performance of the OK model against different factors influencing the interpolation. 36
different data sets were selected from data collected in a study area in the Lower
Arkansas River Valley in Colorado for the assessments of the OK model residuals. The
cross-validation techniques were used to evaluate the performance of the model. The
results showed that the model performance was accurate when using the field-scale data
sets and poor when using the sub-basin scale data sets. The performance of the model
was better when using random or aggregated data sets than when using regular data sets.
The model was found performing better using normally distributed data sets rather than
the skewed ones and also using homogeneous rather than heterogeneous data sets.
2.5 Groundwater Modeling
Water plays a vital role in the development of any activity in the area. Thus, the
availability of surface and groundwater governs the process of planning and
development. The surface water resources are inadequate to fulfill the water demand.
Productivity through groundwater is quite high as compared to surface water, but
groundwater resources have not yet been properly developed in many irrigation
command areas. There are different studies reported for the estimation and management
of the groundwater resources in irrigated areas.
Detailed knowledge of the aquifer characteristics and water table conditions is
most critical for the success of a groundwater management plan. Aguado et al. (1977)
presented a method for sensitivity analysis to determine how variations in parameters
and input data affect the optimal solution of a linear programming management model.
The model uses finite difference approximation of the groundwater equations as
constraints. The optimal locations and discharge rates of wells were determined for
dewatering a rectangular area to a specified level while minimizing steady state total
pumping rate. Sensitivity analysis showed that the optimal steady state solution is most
sensitive to hydraulic conductivity at and near the aquifer boundaries parallel to the
length of the dewatered area. It was concluded that field explorations and testing should
be concentrated on determination of hydraulic conductivity in the area.
The use of embedding technique as a mechanism for coupling the simulation
model of a particular groundwater system with an optimization model was extended to
multi-aquifer systems by Yazicicil and Rasheeduddin (1987). The combined
management model was used to determine the optimal groundwater management
schemes in a hypothetical multi-aquifer system under transient and steady state
conditions. The model enables the determination of optimal allocation of wells in
different aquifers and their pumping rates to achieve a system-wide maximum head
distribution while satisfying the water production targets, well capacity restrictions and
lower bounds on hydraulic heads at critical points. The generated trade-off curves may
enhance the decision maker’s ability to select the best development policy from a set of
alternative policies by considering other technological, financial and legal constraints.
In many surface irrigation projects, the potential for groundwater development
has increased significantly. The additional potential can be used to develop conjunctive
water management plans for augmenting canal water supplies and increasing agricultural
productivity in the project area, if its spatial distribution is known. Sondhi et al. (1989)
presented a methodology for determining the available additional groundwater potential
and its distribution in MRBC Project in Gujarat, India. They estimated groundwater
recharge from the water conveyance and distribution system and the annual water
balance of the project. The spatial distribution of groundwater potential was determined
by recharge distribution coefficients derived from a digital simulation model of the
groundwater basin of the project area.
To address the fundamental question of the ability of the aquifer to yield
sufficient quantity of water for public supply in Nassau County, New York, Maimone
(1991) used two approaches. (i) The hydrograph analysis of water levels over a 45-year
period. (ii) A three-dimensional finite element groundwater model. The results include
an analysis of the aquifer response to the stress of increased consumption and severe
drought. Water balances were developed for each aquifer under predevelopment and
present conditions. It was concluded that purely technical information is not sufficient to
reach a consensus on water issues. Education of the people and other participating
agencies, as well as consensus-building techniques and public relations, are needed to
develop an effective plan.
Excessive stress on aquifers has led to the lowering of water table levels, sea
water intrusion and land subsidence in many parts of the world. The system approach to
groundwater resources is used to investigate different groundwater flow issues. Rastogi
(1993) examined the techniques studying the response of system to various schemes of
groundwater withdrawals from the aquifers and discussed the advantages and limitations
of the techniques. It was concluded that though the development in the techniques of
solution must be kept in mind, however, due to the complexity of the real life problems,
the groundwater system’s approach alone was not enough to address the on-field issues.
In order to optimize well field design and analyze aquifer stress problems,
Richards et al. (1993) applied the USGS MODFLOW code to develop a numerical
model of the Floridian aquifer in the coastal area of Santa Rosa County, Florida. GIS is
the primary tool used in the development of the model grid, performance of the modeling
procedure and model analysis. From the grid coverage, pertinent information is queried
within the GIS environment and used to generate the input files for the MODFLOW
simulation. After MODFLOW execution, simulated heads and drawdown are imported
into the grid coverage where residual error and recharge rates are calculated and contour
surfaces are generated for simulated heads, drawdown, recharge rates and residual error.
Yu, F. and Singh, V. (1994) made a number of theoretical improvements to the
finite‐element formulation for modeling three‐dimensional steady and unsteady
ground‐water flow. The Galerkin method was combined with the collocation method to
handle the time‐derivative term of the governing equation and the resulting system of
ordinary differential equations was solved by using finite integration. More detailed
treatments to leaky boundaries, surface flux boundaries, non-homogeneous and
anisotropic aquifers, and sources/sinks were presented. It was found that the model is
stable, accurate, and numerically oscillation free if proper time‐step size is used.
A general solution scheme for determining ground-water levels for
channel/group-water systems with recharge was developed and verified by Ostfeld et al.
(1999). The analytical solution used the Laplace transform method to solve a linearized
form of the Boussinesq equation. To verify the analytical scheme, three one-dimensional
case studies of flow between two line sources in an unconfined aquifer were explored
through a base run and a set of sensitivity analyses. These runs involved comparisons to
MODFLOW and changes in the boundary conditions and dimensions. Results of the
proposed method matched very well with MODFLOW solutions for all times and
locations using an optimal linearization point.
Rastogi (2001) carried out the simulation of the groundwater flow behavior of the
water table aquifer of MRBC canal command area in Gujarat state, India. Considering
the aquifer recharge occurring from various sources and aquifer withdrawals due
evapotranspiration, pumping and outflow from the region, finite element solutions in
terms of aquifer heads were estimated for the entire flow domain using the technique of
recharge distribution coefficient. A close agreement was noted between the observed and
simulated groundwater head contours for the simulation period.
Hanumangarh and Sri-Ganganagar districts in IGNP command area are facing
severe water-logging and soil salinity problems. Goyal and Arora (2003) used the pre-
monsoon and post-monsoon images of IRS 1C LISS III to generate the maps of water-
logged area and land use/ land cover for the IGNP command in the districts. The analysis
of the generated maps found that 5.9% of the area was water-logged while 10.5% area
sensitive to water-logging. Based on the generated maps, they developed various GIS
data layers using AutoCAD Land Development Desktop (LDDT) software. The GIS data
layers were proposed to be used in the groundwater model MODFLOW to predict the
response of the aquifer to different stresses. It was concluded that RS data can be very
useful for the rapid and accurate assessment of the water-logged area.
Groundwater is a vital water resource in the Choushui River alluvial fan in
Tiwan. A significantly increased demand for water, resulting from rapid economic
development has led to large scale ground water extraction. Overdraft of groundwater
has considerably lowered the groundwater level, and caused seawater intrusion, land
subsidence and other environmental damage. For the sound groundwater management,
Chen (2004) presented a Decision Support System (DSS) for managing water resources
in the Choushui River alluvial fan. The DSS integrates geographic information,
groundwater simulation and expert systems. The GIS effectively analyses and displays
the spatially varied data and interfaces with the ground water simulation system to
compute the dynamic behavior of groundwater flow and solute transport in the aquifer.
Also, a groundwater model, MODFLOW-96 was used to determine the permissible yield
in the Choushui River alluvial fan. Additionally, an expert system of DSS employs the
determined aquifer permissible yield to assist local government agencies in issuing water
rights permits and managing groundwater resources.
McPhee and Yeh (2004) demonstrated the use of groundwater simulation and
optimization to construct a Decision Support System (DSS) for solving a groundwater
management problem associated with the Upper San Pedro River Basin, located in
southeastern Arizona. The case was treated as a multi-objective optimization problem in
which environmental objectives were explicitly considered by minimizing the magnitude
and extent of drawdown within a prescribed region. The proposed algorithm identified a
set of efficient solutions to assist decision makers in selecting a suitable policy.
Sambaiah et al. (2004) presented a study to analyse the impact of canal seepage
and groundwater pumping on groundwater fluctuations to predict the waterlogged area
inan irrigation command area of Indo-Gangetic plains of western Uttar Pradesh, India.
The spatial variation of groundwater heads were predicted using groundwater model
MODFLOW and it was found that post-monsoon groundwater table levels in 1994 had
gone up by 2 to 5 m as compared to those in the year 1990. The simulation results
revealed that the groundwater recharge from different sources, groundwater pumping and
outflow from the aquifer are more or less in equilibrium in the head and tail reaches of
the command area.
Accurate estimation of groundwater recharge is extremely important for proper
management of groundwater system especially in semi-arid regions. Many different
approaches exist for estimating recharge. Sekhar et al. (2004) dealt with groundwater
modeling for assessing the groundwater balance and estimating the recharge in the
Gundal sub-basin, which is located in a semi-arid portion of the Kabini river basin. A
two- dimensional fully distributed groundwater model on the concept of predominantly
lateral flow conceptualized as an unconfined aquifer was used in this study. The
modeling was supported through remote sensing data and GIS. The results of
groundwater modeling, further supported through the groundwater chemistry analysis,
showed the impact of pumping resulting in regional groundwater flows influencing the
hydro-geological regime in the recharge zone.
The Musi river sub-basin which is one of the main tributaries of the Krishna
River, located in Andhra Pradesh, India. The Musi sub-basin is mainly covered by
Archaean granites with Deccan Traps at the Eastern edge. As in a typical hard rock
aquifer region, the yield of the bores decreases with depth due to the reduction of the
fracture density. Hence the risk of water scarcity in case of a drought year is exacerbated.
In order to access aquifer renewable reserves and help groundwater management
authorities, Massuel et al. (2007) calibrated and validated a fully distributed physical
model of the aquifer for a transient state experienced during 1989-2004 by using
MODFLOW. The key variables such as aquifer storativity and transmissivity were
determined by inverse fitting of simulated and observed groundwater levels. The results
presented illustrate that at the sub-basin scale, groundwater modeling in a hard rock
semi-arid context can be a well suited tool for estimating general groundwater resource
evolution.
Groundwater management models are often applied to problems in which the
aquifer state is a mildly nonlinear function of managed stresses. Ahlfeld and Baro-
Montes (2008) used the successive linear programming algorithm to solve such
problems. The algorithm solves a series of linear programs, each assembled using a
response matrix. Stresses were used to estimate response coefficients. The algorithm was
tested on a water supply problem in Antelope Valley, California where large volumes of
water are injected and extracted each year producing a significant nonlinear response in
the unconfined aquifer. The algorithm was found to perform well under a variety of
settings.
Ashraf and Ahmad (2008) used a finite element model (FEFLOW) for regional
groundwater flow modeling in Indus Basin, Pakistan. They generated the thematic layers
of soils, land use, hydrology, infrastructure and climate GIS and developed the numerical
groundwater flow model to estimate the hydraulic heads and groundwater budget of the
aquifer. The model showed a gradual decline in water table from the year 1999. They
studied the impact of extreme climatic conditions i.e. drought and flood, and variable
groundwater abstraction on the regional groundwater system. The results provided the
vital information of the behavior of aquifer in order to organize management schemes on
local and regional basis to monitor future groundwater development in the area.
Due to increasing agricultural requirements, the abstraction of groundwater has
increased manifold in the last two-to-three decades in western Uttar Pradesh. For the
effective ground water management of a basin it is essential that a careful water balance
study should be carried out. Ahmed and Umar (2009) carried out the ground water
modeling to simulate the behavior of the flow system and evaluate the water balance for
the part of Yamuna-Krishni interfluves. The horizontal flows, seepage losses from
unlined canals, recharge from rainfall and irrigation return flows were applied using
different boundary packages available in Visual MODFLOW, Pro 4.1. The river-aquifer
interaction was simulated using the river boundary package. The sensitivity of the model
to input parameters was tested by varying the parameters of interest over a range of
values, monitoring the response of the model and determining the root mean square error
of the simulated groundwater heads to the measured heads. The analysis showed that the
model is most sensitive to hydraulic conductivity and recharge parameters. Three
scenarios were considered to predict aquifer responses under varied conditions of
groundwater abstraction.
Sunderrajan et al. (2009) presented a ground water quality scenario of alluvial
aquifer in central Gujarat, India to highlight the poor drinking water condition. High
salinity, fluoride, nitrite and pollution from industrial effluents have caused
contamination of aquifer. It was suggested that continuous monitoring of the aquifer
water quality is very much necessary along with proper water treatment before its use.
Large amount of groundwater in this aquifer is being used for irrigation.
The radial collector (RC) wells are often preferable to the installation of several
small diameter tube wells, for the withdrawal of large quantity of groundwater from the
alluvial aquifers near riverbeds. Due to the complexities of flow, no exact analytical
solution exists to provide steady state discharge-drawdown relationship for RC well.
Patel et al. (2010) developed a steady state simulation model based on Analytic Element
Method (AEM) to simulate the discharge-drawdown relation for RC well in an
unconfined riverbed aquifer. The Line-sink elements were used to represent stream and
radial laterals with specified conductance. The model was used to study the effects of
different lateral configurations, hydraulic conductivity of riverbed aquifer, radius of
influence and conductance of laterals on the well discharge and drawdown. The results of
simulations were used to arrive at an approximate empirical equation for the discharge of
RC well. The developed model was used for a field problem to obtain the results for
different plausible configurations of RC wells.
Chen et al. (2011) proposed a groundwater level forecasting model based on the
combination of the back-propagation network (BPN) and the Self Organizing map
(SOM). In the proposed model, named as improved multisite SOM-BPN model, the
SOM was used to determine the number of hidden layer neurons, and the Auto-
Regressive Integrated Moving Average (ARIMA) model and semivariogram were used
to determine the number of input neurons. It was found that the single-site and multisite
BPN models can forecast more precisely than the ARIMA model. Moreover, the results
showed that the multisite model is more competent in forecasting groundwater level as
compared to the single-site model.
In order to avert the adverse effects of groundwater overexploitation and also for
developing the groundwater resource potential, it is necessary to augment the
groundwater resource by some artificial means. Provision of percolation tanks in the
ground water basin is one of the best methods of artificial recharge. Venugopal and Lal
(2011) used a finite element based digital simulation model of a groundwater basin for a
hard rock aquifer basin BM 58-59 in Maharashtra, India. The finite element based
numerical groundwater model was used to simulate the groundwater levels for assessing
the performance of percolation tanks for artificial recharge to augment groundwater
resource.
Subsurface drainage models can contribute to the selection of a proper drainage
system and its proper placement in the field. Mirlas (2013) used the groundwater flow
modeling program MODFLOW to simulate groundwater levels in a date palm orchard in
Argaman, in the Jordan Valley, Israel. Using a three-layer groundwater flow model, the
most efficient drainage system was installed at a different spacing between drains.
Installation of the drainage system would cost approximately 30% less than the initially
proposed project. It was concluded that a spatially distributed groundwater flow model
such as MODFLOW can provide more reliable information than different analytical
solutions for planning an effective subsurface drainage system.
2.6 Applications of GIS in Water Resources Management
The collection, analysis and reporting of water use data is a time consuming and
multifaceted process. The inherent complexity of managing a large and diverse database
presents a number of logistical problems that contribute to the lag-time between when
the information is gathered and when it can be used in the planning process. The
database management capabilities of GIS have the potential to expedite the collection of
information from geographically diverse sources. The spatio-temporal attribute of water
use data are ideally suited for analysis using a GIS approach.
The use of GIS can make the task of compiling necessary spatial data and the
required hydrologic parameters for modeling watersheds runoff relatively easy.
Furthermore, recent advances in hydrologic modeling of watersheds have favored the use
of physically based methods such as the geo-morphological instantaneous unit
hydrograph for simulating watershed runoff. The application of this concept in
hydrology can be facilitated by using a GIS to compile the required data base, composed
of various geomorphic and other hydrologic characteristics as spatial data input. Bhaskar
et al. (1992) demonstrated this process for select watersheds within the Big Sandy River
basin in northeastern Jentucky using ARC/INFO.
Schoolmaster and Marr (1992) analyzed Texas water use data for selected
categories in ARC/INFO to demonstrate the utility of GIS for water resources
information management. Examples of data analysis and display were presented to
illustrate the effectiveness of cartographic representation to communicate water use data.
The water resources management is a very complex problem. Any approach in
solving this problem should take into account its wide range of physical, administrative
and land planning components. Jemma (1993) reported a new methodological approach
to water resources management, at basin scale, achieved using GIS data processing
scheme and characterized by a complexity increase with a contemporary synthesis level
increment of the information.
The GIS implementation process starts with the initial decision to use a GIS;
proceeds through system selection, installation and training; and up to data-base
development and product generation. Leipnik et al. (1993) discussed considerations
related to each phase and focuses on other facets of GIS pertinent to water resources
planning and management. Many of these considerations involve critical choices that can
pose significant challenges and impose substantial costs. Understandings of these
challenges can expedite the GIS implementation process.
The sand and gravel aquifer is the sole source of potable water in Escambia
County, Florida. In order to better understand the hydraulics of the aquifer, a numerical
computer model of the aquifer was developed by Roaza et al. (1993). The model applied
a finite element technique which allowed for density-dependent transport and flow in
three dimensions. The model grids were generated by the GIS where nodal and element
sequencing were recorded. The grid topology was stored in the GIS environment with
the element numbers, node numbers and related hydro-geologic attributes. Triangulated
Irregular Network (TIN) allowed a fit of the model grid to the physical dimensions of the
aquifer and for interpolating boundary values for telescopically refined grids. Model
calibration was conducted in GIS through a combination of visual and relational
querying. Thus, the modeling technique was integrated with GIS to develop a system for
optimal management of the resources.
Increasing public awareness, stricter measures and spread of new laws in the area
of water resources have made the use of advanced technologies indispensable. The
application of GIS in water resources is constantly on the rise. Vassilios et al. (1996)
addressed and evaluated the use of GIS in water resources management to stress its
importance for efficient future research and development. They presented and reviewed
different GIS applications including surface hydrologic and groundwater modeling,
water supply and sewer system modeling, storm water and nonpoint source pollution
modeling for urban and agricultural areas, and other related applications. Based on the
reviews, future research and development needs were presented. It was suggested that,
because of the spatial nature of the required data GIS can be utilized effectively in water
resources modeling.
Many regional groundwater models require large, unwieldy data sets and
calibrating them has been a trial-and error, hit-or-miss process. GIS provides automatic
data collection, systematic model parameter assignment, spatial statistics generation and
the visual display of model results, all of which can improve and facilitate modeling.
Researchers and practitioners have achieved this interface in three ways: (i) linking a
GIS to a groundwater model through data-transfer programs; (ii) integrating a model
with a GIS database: and (iii) embedding modeling capabilities within a GIS. Watkins et
al. (1996) emphasized the usefulness of GIS in ground water modeling and evaluated
these three methods of GIS-model interfacing. The current needs were identified and the
suggestions for future work were made.
Lohani et al. (1999) presented a study for water-logged area mapping of Mokama
Group of Tals in Bihar state, India using RS and GIS. IRS 1A LISS II data for pre-
monsoon and post-monsoon conditions were used for identification and delineation of
the water-logged area. The post-monsoon water-logged area map generated using
ArcInfo GIS software was compared with the available submergence data, matching to
the satisfactory level.
India is amongst the largest irrigator countries in the world today. There is,
however, increasing concern about some of the irrigation potential created not brought
into the functional system, low operating efficiency, less crop productivity etc. System
performance monitoring, evaluation and diagnostic analysis are keys to appreciate the
improvement or inefficiency in our irrigation projects. Irrigated lands’ baseline inventory
in spatial and time domains using spatial information technologies provides an array of
performance evaluation matrices to address this issue. Chakraborty et al. (2002) cited a
case study of Nagarjunasagar irrigation project in Andhra Pradesh, India as a realization
of this modern information technology tool. They highlighted how Satellite Remote
Sensing, Digital Image Processing, GIS and GPS help in performance evaluation of an
irrigation project.
Dhiman and Keshari (2002) observed that increasing amount of multiple data sets
available from various sources has created a need for efficient capture, storage,
management, retrieval and analysis of geo-environmental data to address various
groundwater pollution problems of varying nature, dimension and complexity, cropping
at local, regional and basin scale worldwide. They presented a methodology that utilizes
GIS to quantify the spatial geologic data and statistical analysis to determine the relation
between groundwater quality parameters and geological units.
Singh et al. (2002) attempted to select suitable location for groundwater
exploration in hard rock areas using an integrated approach of RS, geoelectrical and GIS.
They assessed the groundwater potentiality of the area through integration of the relevant
layers which include hydro-geomorphology, lineament, slope, aquifer thickness and clay
thickness, in Arc/Info grid environment.
Garcia et al. (2006) introduced a model that utilized GIS to predict relative
reductions in crop yield due to salinity and water-logging at a field scale by
incorporating spatially and temporally variable crops, climatic, and irrigation data to
simulate crop yields. The model utilized soil and water data collected in field scale
studies. The model algorithms were integrated into a GIS as an extension. The resulting
model did not require extraordinary data collection but provided practical insight into the
spatial effects of salinity and water-logging on crop yields.
Indian agriculture is prone to climatic extremes such as flood and drought. Arid
and semi-arid regions, practicing largely rain-fed agriculture are drought prone. Under
such situations, resources conservation for drought proofing can be achieved through
successful implementation of watershed management programs. It accommodates the
interest of the widest possible number of people. Watershed management serves to
conserve and sustain water availability for conjunctive use, food, fodder and fuel, and
livestock production to bring sustainability in livelihood and to improve socio-economic
condition of the people. An over-view of watershed management programs and
experiences in a selected watershed are presented by Khan (2006). Institutional and
policy considerations are discussed to place watershed management into a proper
perspective.
A conjunctive use model was developed by Sarwar and Eggers (2006) to evaluate
alternate management options for surface and groundwater resources. A simple water
balance approach was used to estimate net recharge to the aquifer. The groundwater
model FEFLOW takes net recharge as an input for the water balance calculation and
simulates flow in the groundwater under all boundary stresses. GIS was used to assemble
various types of spatial data. The study revealed that an increase in pumping would
further strain the scarce water resources. Lining of watercourses and adjustment in
cropping pattern could be adopted as alternatives for better management of surface and
groundwater resources.
An understanding of regional groundwater dynamics is required to implement
land and water management strategies. Khan et al. (2007) quantified the impact of flood
and rain events on spatial scales using GIS in the Wakool irrigation district located in the
Murray. Piezometric data were interpolated to generate a water table surface for each
event by applying the Kriging method. Spatial and temporal analysis of major flood
events over the last four decades was conducted using calculated water-table surfaces to
quantify the change in groundwater storage and shallow water table levels. The results
showed that flooding and local rainfall have a significant impact on shallow
groundwater. The study also found that post-flood climatic conditions play a significant
role in the groundwater dynamics of the area. The spatial visualization of the net
recharge in the GIS environment can help prioritize management actions by local
communities.
The United Nations International Decade for Action (2005-2015) of 'Water for
Life’ seeks to prioritize groundwater conservation, possible through remediation and
groundwater engineering. Geospatial technique is fast emerging as the castle of
documentation for effective planning and management. Deogawanka (2011) examined
the various Geospatial applications in groundwater management for effective policy
implementation. It was emphasized that there is a need for the paradigm shift from a
quantitative approach of broad-based aquifer systems or groundwater reservoirs to
localized thematic information mapping, modeled towards native problem resolution and
vulnerability assessment. The paper highlighted the need for groundwater mapping in an
urban environment, where the data can be analyzed for effective rainwater harvesting,
urban flash-flood controls and water engineering decisions.
Groundwater is known as an important source of water supply due to its
relatively low susceptibility to pollution in comparison to surface water, and its large
storage capacity. Moayedi et al. (2011) observed various water quality parameters from
the different monitoring wells through the Labuan Island, Malaysia. The maps of the
different water quality parameters were prepared using GIS. The maps were classified
based on the Malaysia water quality standard. The results clearly showed the different
parts of the study area which are susceptible to groundwater contamination.
Application of GIS provides an accurate and manageable way of estimating
model input parameters, integration of different data layers, conceptualization of model
recharge and discharge sources and visualization of the model output. Ashraf and Ahmad
(2012) presented a numerical groundwater modeling approach integrating RS and GIS
for Indus basin, Pakistan to provide insight in controlling groundwater behavior. They
generated maps for different data layers in ILWIS 3.1GIS software to simulate the
groundwater flow in the basin. Six different scenarios of groundwater recharge/pumping
were simulated in the model to predict the water table behavior. They concluded that the
developed model would provide a decision support tool for evaluating better
management options for sustainable development of land, surface and groundwater
resources on micro as well as on macro levels in future.
Growing demands of water resources along with increasing quality and quantity
issues as a result of rapid urbanization have made water resource management imperative
in India. As the management of water resources and their allocation among competing
demands assumes vital importance due to increasing opportunity costs of water, the
demand management must receive preference over traditional supply management.
Integrated water resource management (IWRM) with multi sectoral convergence is a
very big challenge and is a long procedure for organizing various processes in a single
domain. Nayar and Kavitha (2012) used GIS for integrating the spatially referenced data
in a problem-solving environment. They carried out a study in upper vellar sub basin
located in the Vellar river basin in Tamilnadu state of India and demonstrated the use of
GIS as a powerful planning, implementation, evaluation and monitoring tool for IWRM
and enhance the transparency and accountability of the water Governance. The spatial
database of 25 layers on 8 major themes covering 10187 hectares comprising 150
villages and 500 individual farmers was analyzed in GIS for ensuring transparency and
future service delivery for an effective way. It was concluded that the technology can be
used for linking the spatial data with Aadhaar card or Kissan card, which might become
a reality in future.
Saeed et al. (2012) conducted a study to determine the groundwater quality of
Mardan salinity control and reclamation project (SCARP) area and its suitability for
irrigation purposes. Spatial data of the locations of the water sample wells were taken by
Magellan GPS Receiver. The samples were analyzed in the laboratory and then
compared with the irrigation water quality guidelines suggested by Water and Power
Development Authority Pakistan and FAO. They generated maps for different data
layers in ILWIS 3.1GIS software to simulate the groundwater flow in the basin. The
results indicated that majority of the ground water samples were in the range of marginal
fit category of irrigation water quality. It was concluded that the groundwater at certain
locations get polluted due to seepage and percolation losses from surface.
The long-term sustainability of irrigated agriculture is contingent on application
of cost-effective water conservation measures and improved management in the face of
intense competition for limited freshwater resources from municipal, industrial, and
environmental/ecological interests. A GIS based DSS was presented by Triana
and Labadie (2012) to maximize water savings from efficiency improvements and
conservation measures through integrated management of large scale irrigation systems.
The simulated system predicted the substantial water savings from mixtures of strategies
of varying cost for improved water management and increased delivery system
efficiency and on-farm water conservation.
2.7 Irrigation Water Management and Management Strategies
Irrigation water to the crops is an effective means of enhancing agricultural production
and productivity. Over the past few decades, increase in food production has been
attributed mainly to the expansion of irrigated areas. In addition, irrigation provides the
basis for a better and more diversified cropping pattern and growing of high-value crops,
and thus facilitates overall improvement in socio-economic conditions of the farming
community. Biswas (1990) have highlighted various issues related to water resources
management. He concluded that in spite of the increasing awareness regarding
performance improvement of the irrigation system it may be difficult to identify any
irrigation project that has been monitored and evaluated properly and regularly and
where results of monitoring and evaluation are used to improve the management of
irrigation projects.
Paudyal and Gupta (1990) solved the complex problem of irrigation management
in a large heterogeneous basin by using a multilevel optimization technique. The real
problem consisted of determining the optimal cropping patterns in various subareas of
the basin, the optimal design capacities of irrigation facilities including both the surface
and ground water resources, and the optimal water allocation policies for the conjunctive
use. Various alternative activities, such as surface water diversion and pumpage, ground
water withdrawal and recharge, and alternative future operational scenarios, were
analyzed. A computationally efficient algorithm was developed to solve the multilevel
linear programming model by an iterative procedure.
Karajagi (1991) reviewed the state of the art in water management in India and
presented different methods for its up-gradation. He discussed the basic concepts of
sound water management. It was emphasized that the command area development
programmes and irrigation management and training projects should be implemented
simultaneously in the command area. It was concluded that continuous up-gradation of
the techniques in better water management should be the aim in Five Years Plans to
derive the optimal benefits from the irrigation facilities created.
Mizyed et al. (1991) analyzed the improvements in performance of a water
storage and water distribution system in response to improved monitoring of irrigation
demands. They simulated Mahaweli system in Sri Lanka using a regression model
obtained through implicit stochastic optimization. Spatially independent,
cross‐correlated, and systematic errors in irrigation demands were considered. When the
Mahaweli system was operated optimally, both energy shortages and irrigation shortages
decreased with decreasing standard deviations of error. This indicates that improving the
measurements of irrigation demand would be beneficial to both farmers and hydropower
recipients.
A linear programming model was developed by Afzal et al. (1992) to optimize
the use of different quality waters by alternative irrigations. In a situation of poor‐quality
ground water and limited good quality canal water, the model decided how much land to
put under each crop and how much ground water to abstract and apply to each crop in
each time period. The irrigation system, based on an area in Pakistan, was modeled to
maximize the net returns. To overcome the difficulties of nonlinearity and therefore
greatly reducing computation time, a number of irrigation strategies were identified for
each crop. The developed model presented a solution procedure wherever low rainfall
and limited and different quality waters are the basic parameters governing the irrigation
system.
Steiner and Keller (1992) developed the Irrigation Land Management (ILM)
model to simulate the demand and response of a multiple‐field multi-crop irrigation
system in a variety of environments to assist managers in exploring strategies to improve
system performance. It determined the aggregate irrigation water requirement for a
command area represented by multiple landowners, cropping patterns, and
water‐management schemes. Once the water is delivered, the model simulates the
response of the command area to the water supply. The model was validated using field
data from a large irrigation system in Utah and used to analyze its current management
program.
A software package called Command Area Decision Support Model (CADSM)
was developed by Prajamwong et al. (1997) to estimate aggregate crop-water
requirements and to study management options for irrigated areas. They simulated daily
water and salt balances for individual fields based on crop type and stage of
development, field characteristics, soil properties, possible ground-water contribution
and salinity level. A queuing system was used to allocate available water to command
areas and fields. Average crop yield response was predicted considering root-zone water
deficit, salinity concentration, and water logging. Model verification and calibration
studies were conducted using various climatological data, cropping patterns, and
simulated field conditions.
Carvallo et al. (1998) developed a nonlinear optimization model to determine the
optimal cropping patterns in irrigated agriculture. The objective function of the model
was based on crop-water production functions, irrigation technology used, and costs and
prices of the products. The model was solved using the GAMS-MINOS package and
gave the optimal distribution of areas and crops, irrigation water needs, labour
requirements, and total profit. Sensitivity of the optimal solution to land, labour, and
water resources was examined. Results of the model showed that changes in the prices of
exportable products and water cost have a large impact on the cropping patterns and
profit.
Monitoring and evaluation of the performance of irrigation systems have seldom
been carried out properly and effectively probably because of the reason that the
conventional methods of data collection through field observation are difficult, time-
consuming and cannot be carried out at the same time particularly in large irrigated
commands. Remote sensing techniques are the powerful tools for efficient management
of irrigation systems on large irrigated areas. Ambast et al. (2002) presented the state of
the art on applications of satellite remote sensing that support management of irrigation
systems. They briefly reviewed different approaches being utilized for management of
irrigation systems and also discussed the future perspectives of remote sensing
applications in quantifying irrigation system performance indicators for better
management of water use in irrigated agriculture.
Most of the water resources researchers are sure that the climate changes (natural
and anthropogenic) are likely and they are essentially unpredictable on a local scale,
therefore water resources management should be flexible so as to be able to cope with
changes in availability and demand for water. Bouwer (2002) have discussed at length
various aspects of handling the water related issues which poses threats for the water
availability for different purposes in the 21st century. He emphasized on integrated water
management where all pertinent factors are considered in the decision making process.
Such a holistic approach requires not only supply management but also demand
management (e.g. water conservation and transfer of water to uses with higher economic
returns), water quality management, recycling and reuse of water, economics, conflict
resolution, public involvement, public health, environmental and ecological aspects,
socio-cultural aspect, water storage, conjunctive use of water, water pollution control,
regional approaches and sustainability.
A fundamental shift in irrigation practice is likely to evolve over the next few
decades. Economic pressures on farms, increasing competition for water and the adverse
environmental impacts of irrigation will inactivate new approach to irrigation based on
economic efficiency rather than crop water demand. This new approach which may be
described as optimization has been characterized as a new paradigm by English et al.
(2002). As originally conceived and as generally practiced, irrigation scheduling is
practiced on maximizing yield, hence current scheduling procedures do not explicitly
account for costs and revenues. Optimization, on the other hand, explicitly accounts for
these economic factors.
The water resources problems require the integration of technical, economic,
environmental, social, and legal aspects into a coherent analytical framework. Cai et
al. (2003) presented the development of an integrated hydrologic-agronomic-economic
model for a river basin with major water use in irrigation sector. The irrigation-induced
salinity was a major environmental problem. The main advantage of the model was its
ability to reflect the interrelationships between essential hydrologic, agronomic, and
economic components and to explore both economic and environmental consequences of
various policy choices. The model components were incorporated into a single consistent
model, which was solved by a simple and effective decomposition approach.
Water resources planning involve institutions/groups with different objectives,
responsibilities and interests, and it requires collaboration for resolution of the conflicts.
Cai et al. (2004) discussed the characteristics and modeling requirements of conflict
resolution in water resources planning. They proposed a method based on compound
models for regional water resources planning involving multiple decision makers. It
combines modeling techniques such as multi-objective analysis and multi-participant
decision methods, and supports plan generation and evaluation, preference elicitation,
and negotiation. They concluded that computer models can be effective and useful for
group decisions in water resources planning by facilitating information sharing,
participative model development, and learning processes.
The planning for irrigation water management in an irrigation scheme consists of
the preparation of an allocation plan for distribution of land and water resources to
different crops up to farm level. Optimum land and water allocation to different crops
grown in different regions of an irrigation scheme is a complex process, especially when
these irrigation schemes are characterized by different soils and environment and large
network of canals. At the same time if the water supply in the irrigation schemes is
limited, there is a need to allocate water both efficiently and equitably. Gorantiwar et al.
(2006) described the approach to include productivity (efficiency) and equity in the
allocation process and to develop the allocation plans for optimum productivity and/or
maximum equity for such irrigation schemes. The simulation-optimization technique was
used for optimum allocation of land and water resources to different crops grown in
different allocation units of the irrigation schemes.
Sample and Heaney (2006) presented an approach that incorporated decentralized
options for management of both storm water and urban water supply. The approach can
evaluate the management options of restrictive irrigation policies and rainwater
harvesting. Based upon Soil Conservation Service hydrology, a model was calibrated to
the more complex model using a nonlinear optimizer. They also presented a method for
the comparison of costs and benefits of the selected options.
Smout et al. (2006) presented a case study on Nazare medium irrigation scheme
in India. The allocation plans were developed for optimization of different performance
parameters (productivity and equity) for different management strategies based on
irrigation amount and irrigation interval and cropping distribution strategies of free and
fixed cropping. The results showed that the two performance objectives conflict with
each other and in this case, equitable water distribution may be preferred over free water
distribution at the cost of a small loss in productivity.
Zoltay et al. (2010) developed a generic integrated watershed management
optimization model to select the optimal combination of management strategies and
associated water allocations for designing a sustainable watershed management plan. The
watershed management model integrated both natural and human elements of a
watershed system including the management of ground and surface water sources, water
treatment and distribution systems, human demands, wastewater treatment, water reuse
facilities, aquifer storage and recharge facilities, storm water, and land use. The model
was formulated as a linear program and applied to the upper Ipswich River Basin in
Massachusetts. The results demonstrated the merits of integrated watershed management.
The management of the resource is lagging behind the pace of development, and
often, very little control is exercised in its exploitation in Nigeria. With the rapid growth
in population, urbanization, industrialization and competition for economic development,
groundwater resource has become vulnerable to depletion and degradation. Management
of this valuable resource is determined by its acceptability and utilizability in terms of
quantity and quality. Nwankwoala (2011) emphasized upon the needs of an urgent
overhauling of the machinery of groundwater resources development and management
with the aim of streamlining the overlapping functions of the various agencies that have
operated the system up till now. He suggested the integrated approaches for sustainable
management as well as offered some relevant policy recommendations for groundwater
management.
Raul et al. (2011) observed that the present cropping system in the Hirakud canal
command area in Orissa state, India is under threat due to imbalance between irrigation
water supply and demand. The canal water supply meets merely 54% of the irrigation
demand. They carried out a Quasi-three-dimensional groundwater flow simulation
modeling by using Visual MODFLOW to detect the change in hydraulic head due to
transient pumping stresses. The enhanced pumping scenarios showed that groundwater
extraction can be increased up to 50 times of the existing pumping without causing any
adverse effect to the aquifer but the aquifer does not permit to exploit water in order to
fulfill the irrigation water demand. Hence, it was suggested to develop an optimal land
and water resources management plan for the command area.
Groundwater is a treasured earth resource that will continue to be the most
important sources of fresh water in future. Rejani et al. (2011) discussed a case study of
the coastal groundwater basin of Balasor district in the state of Orissa, India. They
determined the optimal cropping pattern and net annual returns for different seasons
(monsoon and non-monsoon), soils (saline and non-saline) and irrigation practices
(rainfed and irrigated) in three administrative blocks of the basin by considering the safe
yield of the aquifer and the maximum permissible pumpage of the wells as the major
constraints. The results of the study revealed that by adopting cropping pattern
corresponding to wet, normal and dry years, the net return of the basin can increase by
257%, 167% and 112% respectively. The sensitivity analysis showed that the market
price of the high valued crops, availability of land and water resources and the cost of
cultivation are the most sensitive factors affecting the net profit of the basin. The
adoption of optimal cropping patterns, coupled with on-farm rainwater harvesting is
strongly recommended for the study area for the sustainable management of vital
groundwater resources.
Integrated water resources management (IWRM) is considered a path to bring
many elements within the development schemes together toward a unified land-water
planning and management process. An IWRM model was developed by Ahmadi et al.
(2012) to connect three groups of decision makers in pollution control, agricultural
planning, and water resources allocation with economic, environmental, and social
objectives. They developed a genetic algorithm–based optimization model for providing
desirable water quality and quantity while maximizing agricultural production in the
upstream region, mitigating the unemployment impacts of land use changes, and
providing reliable water supply to the downstream region. The study presented a
practical mean of integrating water quality and quantity management and land use
planning on a watershed scale.
The climate change is likely to have impact on the hydrological cycle and
consequently on the available water resources and agricultural water demand, there are
concerns about the effects of climate change on agricultural productivity. Karamouz et
al. (2013) developed an agricultural planning model in order to optimize the cultivated
area, crop pattern, and irrigation efficiency based on the estimations of crop water
requirements, water availability, and water allocation to irrigation. The Aharchay
watershed located in the northwestern part of Iran was selected as the case study. For
crop water requirement estimation, the output of an atmosphere- ocean general
circulation model was statistically downscaled and used as inputs to a computer model.
The results of the study showed the significance of using different tools and methods in
assessing and allocating water resource in regions with scarce water resources.
Liu et al. (2013) described a coupled modeling approach to analyze sustainable
management strategies in surface–groundwater conjunctive use irrigation districts in the
lower Yellow River Basin. An appropriate irrigation schedule and an optimal range of
groundwater levels were first established using the soil water atmosphere plant (SWAP)
model. The integrated surface water and groundwater model was then set up using
modified SWAT2000 and MODFLOW models. The two models were connected through
standardized simulation grids and calibrated using field measurements. Five scenarios
that were designed according to different well-canal irrigation supply ratios and the
irrigation schedule determined by SWAP were tested using the integrated modeling
approach. It was proved that conjunctive management strategies of canal diversions and
tube-well pumps can effectively reduce phreatic evaporation losses, increase water use
efficiency, and sustain groundwater levels while maintaining crop yields at current
levels.
Karamouz et al. (2014) presented an economic framework of all potential benefits
and costs arising from present activities and implementation of policies. It included the
crop production costs, capital and operating costs of development projects, pumping
costs, and costs imposed by reduced crop production. The water supply and demand
system of the Rafsanjani Plain, in the central part of Iran was simulated into two
different models. The management scenarios were generated considering different
strategies including the inter basin water transfer, improvements in irrigation techniques,
limiting future expansion of cultivated area, and restricting withdrawal from
groundwater. The study demonstrated how combining multiple tools and techniques
along with an economic framework could effectively assist decision makers to
understand the consequences of a taken strategy in a specific region.
2.8 Concluding Remarks
The water resources problems encounters a unique set of physical condition to which it
must confirm, hence standard solution can rarely be possible. It is imperative to
formulate a sustainable, self-reliant and integrated water resources development plan for
the future keeping in mind the hydrological, climatological and socio-economic
constraints of the region. Conjunctive use of surface water and groundwater in the
irrigation command area has been recommended by the researchers since long back. The
review of the geostatistical studies carried out in the past reveals that most of the
researchers in the area related to groundwater seem to have worked with Kriging. As
perhaps the best estimation technique, Kriging provide results that can be used as
reference in comparative performance evaluation.
In order to take advantage of GIS in improving water resources planning and
management, it needs to be linked with traditional mathematical models. GIS based
groundwater modeling is found to be the ultimate choice of the researchers in the present
time. Different researchers have contributed to address the issues of water resources
management in the canal command areas considering various aspects such as:
hydrological conditions, geostatistical modeling of groundwater levels, conjunctive use
of water, groundwater modeling and irrigation water management. Different researchers
have worked for the irrigation related problems in the MRBC command area in the past.
The branch canal command level issues appeared to remain less addressed in the studies
comprising the large canal command area of MRBC. The present research is taken up
with the idea of a comprehensive study for the Matar branch canal command area,
incorporating hydrological aspects, geostatistical analysis, groundwater modeling and
budgeting, future predictions for groundwater levels and estimation of safe aquifer yields
under various uncertainties of the rainfall; and to identify the water resources
management options for the Matar branch canal command area of MRBC.