In the book, Karaji includes groundwater exploration techniques such as wells and qanats—techniques still used today in many parts of the Middle East and Asia. By the late 1960s, too many water rights had been allowed, allowing overdevelopment of the High Plains aquifer, resulting in the extraction of groundwater resources (Sophocleous 1998).
Incorporating Ecohydrology into Integrated Groundwater Management
These examples show the importance of understanding the eco-hydrological processes specific to the problem – in this case water uptake by trees – in order to design effective methods for integrated groundwater management. In this way, integrated groundwater management provides a relevance that may be lacking in simple academic ecohydrological endeavors.
Summary
Reilly TE, Dennehy KF, Alley WM, Cunningham WL (2008) Groundwater availability in the United States, United States Geological Survey Circular 1323, 70 p.http://pubs.usgs.gov/circ/. Robinson T (1965) Introduction, distribution and surface area of salt cedar (Tamarix) in western United States, United States Geological Survey Professional Paper 491-A, 12 p.http://pubs.er.
Introduction
Classes of GDEs and Relevant Groundwater Attributes .1 GDE Classification
Depth to groundwater (from the land surface) is perhaps one of the most important groundwater characteristics for GDEs (Eamus et al. 2006). An increased depth to groundwater can lead to reduced plant growth, mortality and changes in species compositions (Shafroth et al.2000).
Identifying GDEs
An idealized representation of the groundwater depth soil pattern in a shallow, unconfined aquifer is shown in Figure 13.2. An example of using 18O isotope analyzes of xylem water, soil water, and groundwater is shown in Figure 13.3.
Estimating Rates of Groundwater Use by Class III GDEs
Further examples of estimating groundwater consumption rates using the White method can be found in Lautz (2008), Martinet et al. Methods for estimating vegetation water use rates include eddy covariance (Eamus et al. 2013), measurement of sap flow rates (Zeppel et al. 2008), and remote sensing estimates (Nagler et al. 2009).
Threats to GDEs
Seasonally, the depth to groundwater fluctuates around 0.5-3 m, with a maximum depth occurring in late summer. This result highlights the importance of the rate of increase in groundwater depth in determining the response of species and communities.
Concluding Remarks
Hershler R (1998) A systematic review of the hydrobiid gastropods (Gastropoda: Rissoidea) of the Great Basin, western United States. Leblanc M, Razack M, Dagorne D, Mofor L, Jones C (2003b) Using Meteosat thermal data to map soil infiltrability in the central part of the Lake Chad Basin, Africa.
Introduction
Given this wide range of concerns, this chapter focuses on examples of how water quality issues affect integrated groundwater management. This chapter will present three examples that demonstrate how water quality factors can affect groundwater use and related management options. Because the range of potential socially relevant water quality issues is large, we focus here on transferable elements contained in the examples.
Contaminants that Affect Acceptable Water Quality Determinations
These actions are often used in combination and include a range of capital costs incurred during initial implementation as well as ongoing operation and maintenance costs. As might be expected given the range of costs and the range of potential concerns shown in Table 14.2, there is no single or universally recommended approach to addressing water quality issues in an integrated groundwater management framework. . Therefore, groundwater management examples are used to illustrate applications where one or more of the actions described above are considered.
Three Examples of Water Quality Issues and Integrated Groundwater Management
For example, near Tampa, Florida, much of the downward movement of groundwater is along flow paths that follow natural conduits in the limestone soil (Jagucki et al. 2009). Human activities can recharge or alter groundwater flow in ways that lead to changes in aquifer geochemical conditions (Eberts et al. 2013). They can affect the quality of drinking water; especially groundwater near land surface (e.g. Schreiber et al.1993).
Implications for IGM
Focazio MJ, Szabo Z, Kraemer TF (2000) Occurrence of selected radionuclides in groundwater used for drinking water in the United States - an exploratory study, 1998. Focazio MJ, Kolpin DW, Barnes KK et al (2008) A national exploratory study for pharmaceutical products and other organic wastewater contaminants in the United States – II) untreated drinking water sources. Szabo Z, dePaul VT, Fischer JM, et al (2012) Occurrence and geochemistry of radium in aquifers used for drinking water in the United States.
Introduction
Finally, there is a section on integration and conclusions where we illustrate how management to mitigate salinization should be integrated with policy to reduce the threat to productivity that occurs with groundwater degradation. The first is representative of a developing country and explores the management of salt-affected soils in the Indus Valley, Pakistan, while the second looks at a developed country and illustrates how through monitoring we can infer the causes of shallow aquifer salinity in the catchment. Namoi of NSW. Finally, this chapter will show how management to mitigate salinization should be integrated with policy to reduce the threat to groundwater productivity and degradation.
Major Types of Soil Salinity Based on Groundwater and Soil Processes
Salts eventually reach the surface via the discharge zone through capillary rise, and high salinity levels in the soil can develop that are not conducive to agricultural production. Salt accumulation in root zone layers where the water table is deep is called transient salinity and generally salt concentrations fluctuate due to soil processes. Several sources of salts (as outlined in subsequent sections) contribute to the salts in the soil profile, and these are concentrated due to evapotranspiration and lack of adequate leaching.
Physical and Chemical Processes Causing Salinization of Root Zone Layers and Aquifers
These salt stores in the root zone can greatly affect plant growth and soil processes (Figure 15.3a) and can also affect groundwater supplies deeper in the landscape if recharge conditions change and there is a net downward flow of water and thus salt. 15.3 (a) Salt accumulation in the root zone and effects on plant growth and soil processes. b) Development of transient salinity (after Rengasami 2006). CROSS includes the different effects of Na+ and K+ in the scattering soil. Table 15.1 Categories of salt-affected soils based on ECe (dS/m), SARe and pH1:5 of soil solutions and possible mechanisms of effect on plants.
Salinization Case Studies
Wheat and cotton yields begin to decrease with increasing salinity levels for each year. First, for the extremely degraded soil type D1, the agronomic strategy will result in the highest farm profits in the next 25 years. In the late 2000s, the Namoi Catchment Management Authority (CMA) commissioned a study to assess groundwater salinity changes in both the Lower and Upper Namoi catchments (Timms et al. 2009).
Integration and Conclusions
As shown in the two case studies, management strategies to reduce salinity both in the root zone and/or in aquifers also need to be carefully integrated with policy. Andersen MS, Acworth RI (2009) Stream-aquifer interactions in the Maules Creek catchment, Namoi Valley, New South Wales, Australia. Kahlown MA, Azam M (2002) Individual and combined effect of water logging and salinity on crop yield in the Indus basin.
Introduction
It is commonly performed in the United States, and now increasingly in Europe (Levantesi et al. 2010). Consequently, traditional urban drainage systems now cause many technical and environmental problems, especially the pollution of surface receiving media (Chocat et al. 2007). The main objective of the MAR here is to create a hydraulic barrier to prevent the intrusion of pollutants and saline waters (Casanova et al. 2007,2008).
MAR Technologies .1 Infiltration Methods
However, rainwater can be one of the main sources of pollutants (heavy metals, hydrocarbons and other organic compounds) produced by cities. This results in an inversion of water circulation in the well casing and in the surrounding aquifer, thereby reducing plugging (Dillon et al. 2006; Pyne2005, 2006). The main purpose of this technology is to use the geocleaning capacity of the river bank to filter and clean the recharge water.
Sources of Water Used for MAR
Due to the relatively small quantities produced and their very high cost (Dabbagh2001), desalinated water is almost never used for MAR, the purpose of which is to significantly increase the volume of groundwater. The discharge of this water is subject to a specific study and pre-treatment is usually required. This means that this water is not systematically discharged into the municipal sewage system, thus limiting its use.
Hydrogeological and Regulatory Constraints
Regarding water quality, when selecting a MAR site, one must be sure that the quality of the recharge water is compatible with the reactive potential of the aquifer matrix and especially that of the unsaturated zone. It is therefore essential that the safety for public health and the environment of the artificial recharge caused by the addition of water to a pack and its transport to the aquifer through the unsaturated zone is ensured. If this catchment area includes a MAR installation, the restrictions on the quality of the infiltrated water are even stricter.
Health and Environmental Risks
Wells used for drinking water supply can be placed downstream of the target MAR sector with water of degraded quality. The potential theoretical risk is related to any disturbance that could affect the various characteristics of the aquifer as a result of the installation of the MAR system. A theoretical risk assessment therefore requires the determination of: (i) possible sources of contamination of the used filling water, such as long-term contact with minerals rich in trace metals, industrial discharges or the presence of a nearby hospital; and (ii) the internal chemical and microbiological quality of the recharge water.
Implementing MAR .1 Hydrogeology Study
Analysis of the mineralogy of the unsaturated zone makes it possible to determine the concentrations of oxyhydroxides and clay minerals, which are the solid phases that have the greatest affinity for contaminants. However, an initial, generic approach should make it possible to identify and approximate the potential biological activity (of the soil itself, or of the injected water) that will play a role in the evolution of the main mineral phases of interest in terms of concerns. : physical and chemical characteristics of the soil (dissolution/precipitation), and in some global reactions to be determined (decomposition of organic matter, redox reactions of Fe, S, Mn, etc.) depending on the nature of the injection. water and land (Azaroual et al Pettenati et al.2012). The costs and benefits of different management solutions (including environmental costs and benefits) should be systematically assessed in close collaboration with the hydrogeological study (Shah2014).
Case Study of the MAR in France
MAR is one of the instruments that can be used for an integrated quantitative (and/or qualitative) management of ground and surface water resources. In most of the cases identified in France (Casanova et al. 2013), the main objective of MAR is to sustain an overexploited groundwater aquifer. However, stormwater is one of the main sources of pollution (heavy metals, hydrocarbons and other organic compounds) produced by cities.
Conclusions
MAR is one of the strategies that can be used for quantitative and qualitative water management and adaptation to climate change in the field of water resources. The selection of a MAR site therefore requires that the quality of the recharge water is compatible with the reactive processes in the soil, especially in the unsaturated zone. Azaroual M, Pettenati M, Casanova J, Rampnoux N (2009) Reactive transport modeling of contaminant transfer through an unsaturated soil zone under artificial aquifer recharge under seawater intrusion constraints.
Introduction
Managed Aquifer Recharge to Date
There are countless examples around the world that demonstrate the value of managed aquifer recharge. Water quality is rarely managed intentionally, so it can be argued that this recharge is not yet managed aquifer recharge. A progression is now underway from uncontrolled disposal via swamps, basins, wells and karst features to managed aquifer recharge through implementation measures to improve and protect water quality.
Potential for Managed Aquifer Recharge from Urban Stormwater in a Suburban Area of SA, Australia
For low-permeability formations, levelized recharge costs increase because capital and operating costs are amortized over smaller water volumes and because additional water treatment may be required to avoid plugging the well. A more recent study of stormwater recharge in the Northern Adelaide plains (Dandy et al. 2013) found levelized costs of A$1.57/KL (including the land value of the harvesting facility and capital and operating costs of distribution system for open public space irrigation This is exacerbated where local groundwater has high enough salinity that density-influenced flow occurs (Ward et al. 2009) and a freshwater injection lens forms at the top of the aquifer.
Potential of Managed Aquifer Recharge from Large Floods Events in a Rural Irrigation Area of NSW, Australia
Within existing rights for consumptive uses, Rawluk et al. 2013) discussed the potential sources of water for MAR in the Murray Darling Basin. Figure 17.5 shows the proportion of irrigation and environmental water for each of the supplementary water events in Lower Namoi from 1972 to 2012. In the base case, the only cost considered is the cost of harvesting 200 ML of flood water and the cost of annual farm maintenance .
Conclusion
Arshad M, Qureshi M, Jakeman A (2013) Cost-benefit analysis of farm water storage: surface storage versus managed aquifer disposal. Dillon P, Fernandez EE, Tuinhof A (2012) Management of aquifer recharge and discharge processes and aquifer conservation balance. Pyne RDG (2010) Aquifer conservation recovery: economics and recent technical advances in achieving sustainability and reliability of groundwater supplies through managed aquifer recharge.
