Preface

Water is essential for all living things. It covers 70% of our world and is also an important part of our bodies. However, only about 0.3% of the water resources on Earth is usable and potable. The use of this limited resource varies depending on demographic, economic, technological, and climatic characteristics. The consumption of water for domestic, industrial, and agricultural purposes has increased by 15% in the last two decades, and today one out of every three people is faced with the danger of water shortage. Since the population and water resources worldwide do not show a balanced distribution, nearly a hundred countries hosting almost half of the world's population suffer from water shortages.

Today's rapid population growth, water-consuming industries brought by technological developments, and epidemics spreading much faster due to globalization have greatly increased the need for water. In addition, global climate change, evaporation, and deterioration of rainfall balances also lead to negative consequences such as floods and droughts. It has been determined that surface and groundwater resources cannot meet the increasing demand for potable and thus used water and wastewater need to be recycled. However, issues such as protection of water resources, balanced water consumption, treatment of wastewater to a certain level, and realization of water recovery have shown that versatile water management should be introduced. To conserve water, both management and public strategies have been developed, alternatives have been revealed to reduce water consumption in industrial/commercial applications, and methods such as smart irrigation systems have been proposed in agriculture. Local authorities have focused on infrastructure operations to prevent water losses, and flow measurements have begun to be followed more closely. The use of greywater for partial recycling of water for household purposes and rainwater harvesting systems have started to be encouraged.

This edited volume consists of six chapters. Chapter 1 presents the general method of planning support in the areas of water and land use. Chapter 2 evaluates diffuse runoff from the drainage basin of a small river with agricultural land in the drainage basin and discusses the measures taken to protect the river waters from pollution. Chapter 3 examines the relationship between spatiotemporal land use/cover change and watershed health by using remotely sensed data. Chapter 4 identifies the main pollutants in different seasons and estuarine reaches by multivariate statistical methods, which are expected to help managers to understand the water body system along the estuary. Chapter 5 sheds light on the design of various incentive schemes to face groundwater over-exploitation by farmers who can over-pump water typically by manipulating their water meters in an

asymmetric information context. Finally, Chapter 6 reviews the applications in which nanoparticles are used in water/wastewater treatment that play an indirect role in water conservation.

The editor would like to thank the authors for their contributions.

### **Murat Eyvaz**

Associate Professor, Department of Environmental Engineering, Gebze Technical University, Kocaeli, Turkey

### **Ahmed Albahnasawi, Ercan Gürbulak and Ebubekir Yüksel**

Gebze Technical University, Kocaeli, Turkey

### **Chapter 1**

## Regional Water and Land Use Planning: Systematic Planning Support

*Harro Stolpe, Nguyen Ngoc Ha and Christian Jolk*

### **Abstract**

Sustainable water and land use planning is an important component of regional planning. Regional planning, as a multi-sectoral concept, serves as a framework for sub-regional and local planning. Water and land use planning needs as comprehensive a system understanding as possible, of water and land uses. This forms the basis for managing water resources quantity and quality, in coordination with the existing land use. The developed systematic GIS-based planning approaches, for a sustainable water allocation and water quality conservation, as well as the resulting recommendations for actions, supports water management on a regional and local planning level. The developed concepts are illustrated by up-to-date project results of the R&D research projects "ViWaT-Planning" Stolpe et al., in the Mekong Delta in Vietnam and "iWaGSS" Jolk et al., in the Olifants River Basin in South Africa. Both R&D projects are funded by the German Federal Ministry of Education and Research (BMBF) and are coordinated directly with existing water management institutions and their measures in both countries. The focus of this publication will be on the general methodology of planning support, in the fields of water and land use.

**Keywords:** regional water and land use planning, Mekong Delta, Olifants River

### **1. Introduction**

Several research projects developed by the Institute of Environmental Engineering + Ecology (EE+E), at the Ruhr-University Bochum, assess water and land use at the regional level to support spatial planning. These research projects are located, mainly, in Vietnam and in South Africa, under different spatial and climatic conditions. **Table 1** characterizes the different investigation areas [1–5].

In each R&D project, the central core of the work was to analyses the current water and land use system, in a transparent and systematic way. This analysis aids in designing suitable management measures for water resources, with regards to water quantity and water quality.

Based on the investigated current state of water management in the different water systems, problems and problem areas are identified and needs for action are described and prioritized, on a regional scale. The results of the aforementioned R&D projects, is a systematic planning support system, for identifying problems and conflicts, in water and land use management.

Systematic water and land use planning is understood as a continuous process that must be able to respond to changing natural conditions and land use


### **Table 1.**

*Regional water and land use projects in Vietnam and South Africa, performed by the EE+E.*

innovations. Updates are, therefore, required from time to time. Such updates can be done, effectively, within a geodata management system. Such a system has to involve the planning levels relevant to water and land use issues:


This top-down process enables the higher levels to influence the lower levels. Conversely, it should be accompanied by bottom-up processes, for the lower levels to be considered at the higher levels. Only in this way can a continuous planning process be adapted to the constantly evolving innovations.

The basis for such a planning system approach is a suitable collection, harmonization and evaluation of the relevant water and land use related information, as well as a generally comprehensible presentation and visualization of the various planning issues, to support decision making. This process is to ensure the scientific soundness and application of advanced technologies, the connectivity, the forecasting ability, the feasibility, and the effective and thrifty use of the land and water resources; the objectivity, publicity, transparency and conservation (e.g. in Vietnam: Clause 5, Article 4, Law on Planning No. 21/2017/QH14).

The methodologies developed in the different R&D projects (see **Table 1**), used modern techniques of data acquisition, harmonization and processing, as *Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*

well as methods to evaluate and visualize the results with the help of Geographic Information Systems (GIS).

This publication summarizes experiences gained from several research projects, funded by the German Federal Ministry of Education and Research (BMBF), related to data management and spatial decision support.

All projects were carried out in close cooperation with a high number of responsible institutions in Vietnam (e.g. MOST Ministry of Science and Technology, MONRE Ministry of Natural Resources and Environment, NAWAPI National Center of Water Resources Planning and Investigation as well as local responsible authorities) and in South Africa (e.g. DWA Department for Water Affairs, DWS Department of Water and Sanitation, The WRC Water Research Commission, Kruger National Park and SAEON South African Environmental Observation Network, etc.).

### **2. Methodological approach**

The central objectives of the R&D projects, listed in **Table 1**, was to develop a systematic and updatable GIS-based planning support approach, to describe and analyses the current state, future states and the respective problems, on water and land use management.

A prerequisite to this work, is to acquire and develop a structured collection of the relevant data on water and land use. In both countries Vietnam and South Africa, a large amount of relevant data exists, but it is not always systematically collected, stored and evaluated.

The most important step in the methodological approach is to store the scattered data sets of varying topicality (administration, topography, population, water demand, water resources, water quality, sensitivity of water resources, etc.) in one centralized location, for example, a geodatabase. Additional steps include the harmonization of the data sets as well as to check the data sets on their plausibility.

**Table 2** shows some of the varying constraints to data collection in Vietnam and South Africa, on which the sometimes-time-consuming initial phase of regional water and land use projects, depends.

Based on the collected data and information, including the aforementioned harmonization and plausibility checks, a water and land use planning information system, as well as GIS-based water and land use planning maps for decision makers, were developed.

Based on the systematically collected, stored and evaluated database different methods to analyse water quantity as well as water quality, were developed (see **Figure 1**).

For water quantity aspects, methods were developed to compare water demands/water uses with water resources:


**Table 2.**

*Different data handing in Vietnam and South Africa.*

### **Figure 1.**

*Structure of the water and land use planning system and planning maps.*


For water quality aspects, methods were developed to combine contamination potentials of land uses (agriculture, settlements, mining, industry, etc.), with the sensitivities of the water resources (surface water, groundwater, ecology).


Based on the systematic approach outlined in **Figure 1**, a number a different water resources planning maps, have been developed. They represent water quantity as well as water quality issues. All the thematic maps were visualized in water planning maps (in some cases bundled in a Water Management Atlas or in a Web-GIS system [5]).

An important task was to design the work in such a way that it does not depict conditions that are valid in the short term, but rather derives planning-relevant statements that are valid in the longer term.

*Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*

This publication discusses examples for the determination of the usable water quantity in the Mekong Delta, in Vietnam and for the determination of contamination risks in the Olifants river basin, in South Africa.

### **2.1 Available water quantity (example of Vietnam)**

In accordance with the aforementioned planning levels, at the national level in Vietnam, the Planning Law No. 21/2017/QH14 [6], 2017, the Resolution No. 120/ NQ-CP, 2017 [7] and the Decree No. 37/2019/ND-CP [8] are of basic importance in the context of water and land use planning. At the regional level, Decree No. 37/2019/ND-CP is of importance.

Based on these legal preconditions, the starting point of any planning-oriented water and land use management consideration, is to carry out an adequate system analysis. The system analysis should present the essential qualitative and quantitative interdependencies, as a basis for the planning assessments.

The project area, situated within the Mekong Delta (see **Figure 2**), is located in the South of Vietnam. It includes seven provinces, south-west of the Hau River, with an area of 22,000 km2 and contains approximately nine million inhabitants.

### **Figure 2.**

*Mekong Delta water and land use system in the dry season (Arrows: blue = fresh water from Hau River, red = saline water exchange/intake. Water bodies: blue = fresh, red = saline, green = alternating fresh/saline).*

The Mekong Delta is a tropical delta area with terrain elevations mainly between 0 and 50 cm A.S.L. The Delta is a complex system of rivers, canals, rice paddies, aquacultures and wetland ecosystems, as well as infrastructure for water supply and irrigation.

The prominent feature of the Mekong delta is the existing dense water network of mostly human-made canals with various functions, including: ship transportation, irrigation, waste water discharge, water storage, etc. Characteristic for the Mekong Delta is the existing effective regional freshwater and saltwater management, controlled by weirs and sluice gates, with different water management functions, such as fresh water intake, fresh water and saline water separation, saline water intake and saline water discharge. These functions enable or constrain different land uses (rice and fruit production in freshwater areas, shrimp aquaculture in saltwater areas).

The driving forces for this water management are the tides and the changing water flows during the rainy and dry seasons. The tides and seasonal water levels allow for a recurrent exchange of fresh and salt water in the Mekong Delta.

The agricultural areas, such as rice and fruit production, are fed by freshwater from the Hau River. The areas with saline water from the sea are characterized by saltwater fish and shrimp farming.

Current trends show a significant decline in rice areas and an increase in aquaculture and settlement areas. Natural areas are only present in remaining areas. The land use planning under the first Mekong Delta Integrated Regional Plan (MDIRP) reinforces this trend as the influence of salt increases due to sea level rise, land subsidence and the decline of inflows into rivers.

### *2.1.1 Water demand, water resources in dry season*

In the following table, the focus is on the dry season, as this is the critical time for ensuring water supply.

Within the study area, there are different water demands related to different land uses. There is a demand for fresh surface water in the rice areas, a demand for saline seawater, as well as a demand for fresh groundwater, in the aquaculture


### **Table 3.**

*Main water and land uses in the Mekong Delta according to the map in* **Figure 2** *water demand, water resources, problems and measure need.*

*Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*


### **Table 4.**

*An example of land uses and water demands from so-called subregion III, a freshwater area in the northwest of the study area (see Figure 2) near the border to Cambodia.*

areas and alternating water demand (saline seawater and rainwater) in the rice-shrimp areas. Additionally, there is a demand for rainwater in the rainfed wetland/rice areas. **Table 3** provides the basic information on water resources and the associated water demand for the main land use types (see **Figure 2**), in the Mekong Delta.

In determining the water demand, the following water use sectors are considered: agriculture, aquaculture, domestic water, drinking water, etc. A method for estimating total water demand, according to the current land use classifications by the Vietnamese Ministry of Natural Resources and Environment (MONRE), was developed and applied.

In the freshwater areas along the Hau River in the north-east of the study area, the main user of large quantities of freshwater, in the dry season, is rice cultivation (see **Table 4**). The demand for water can be supplemented by water storage in small canals, from the rainy season, as well as inflows from the Hau River. The water demand for residential land uses, in this area, is covered by surface water from the Hau River or groundwater.

In the saline areas in the southwest, where there is no relevant demand for fresh water for irrigation, the main sources of freshwater come from groundwater extraction, rain water harvesting as well as storage (e.g., for domestic purposes, food processing, etc.).

### *2.1.2 Problems, contradictions, need for action*

The following problems with different land use and their associated water demands, become apparent:


Water demand, water use and water resources, as well as the resulting problems and contradictions, are depicted in corresponding planning maps and underpinned by results from mathematical models. Proposals for the avoidance and improvement of water and land use are derived from this.

### **2.2 Contamination risks (example of South Africa)**

South Africa is facing major challenges in the water sector. The uneven distribution within river networks and insufficient precipitation leads to water-supply shortages, especially in dry season. Additionally, water infrastructure and the management of water supply and waste water treatment, is in deficit. The rapid industrial growth, the progressing urbanization and the industrially organized agriculture, lead to increasing water demand and water quality problems [2].

The investigated Olifants River Basin is located in the provinces Limpopo, Gauteng and Mpumalanga, in the northeast of South Africa (see **Figure 3**). It has a total area of 54.626 km<sup>2</sup> .

In contrast to the Mekong Delta, the Olifants River Basin has a semi-arid climate and, therefore, stressed water resources. Economically, it is characterized by intensive mining activities, irrigated and rainfed agriculture and tourism (Kruger National Park). Surface water, stored in dams and reservoirs, supplements most of the water demand. The largest dams are: Loskop Dam and De Hoop Dam (see **Figure 3**).

**Figure 3.** *Olifants River Basin.*

*Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*

### **Figure 4.** *Lithology [9–12].*

The Olifants River Basin is characterized by two main river systems: the Olifants and Steelpoort Rivers (see **Figure 3**). Groundwater use is limited to only one exploitable aquifer, formed by basalts. The rest of the river basin consists primarily of sedimentary rocks (e.g. sandstone) and intrusive igneous rocks (e.g. granite) (see **Figure 4**).

Water quality issues are a limiting factor for the socio-economic and environmental development in South Africa. Many studies in South Africa focus on the negative side-effects of dynamic population and economic growth, industrially organized agricultural practices and contamination potential, originating from the mining sector. In addition to these topics, inefficient water infrastructure is also one of the main problems [2].

The Water Quality Report of the Department of Water Affairs [13] and the Planning Level Review of Water Quality in South Africa [14], provides an assessment of the existing conditions of water quality in the Olifants River Basin.

According to Van Veelen [13], the analysis results of the water quality in the Olifants River Basin highlight the following: salinity related impacts due to mining, power generation and industries; unacceptable EC concentrations due to irrigation return flows; acid mine drainage; mesotrophic to eutrophic dams; unacceptable phosphate concentrations in rivers; unacceptably high levels of heavy metal concentration in parts of the catchment; pesticides and herbicides in rivers due to agricultural activities.

This wide range of water quality-related problems, needs a holistic and efficient research approach. The method developed for assessing contamination risks, includes consideration of the following contamination pathways:


In this publication, only the sensitivity of the groundwater resources and the contamination potentials of agriculture, are determined and aggregated, to contamination risks on a sub-basin level.

### *2.2.1 Sensitivity of groundwater resources*

**Figure 4** illustrates the lithology of the Olifants River Basin. The runout evaluation of the uppermost groundwater aquifer was carried out, based on the lithological classes and is described via their hydraulic conductivity in the hydrogeological map series of the Republic of South Africa [9–12]. Overlying strata above the aquifers were not considered, as these cannot be safely assessed at the chosen scale of 1:1,300,000. As the protective effect of overlying strata is ignored, the classification of resource sensitivity lies within secure margins. The consideration of overlying strata is to be included in subsequent planning levels.

The resource sensitivity of groundwater is established for the uppermost groundwater aquifer, also taking into consideration groundwater use. Groundwater resource sensitivity is classified, based on runout and groundwater use as per **Table 5**.

**Figure 5** depicts the groundwater resource sensitivity in the Olifants River Basin. Areas with groundwater extraction and use are characterized by very high resource sensitivity. They are shown, using a hatched pattern. This characterization is based on existing risks through contaminant inflow, due to informal and illegal borehole construction or borehole use. A further justification for this characterization is the special need for protection of the directly used groundwater resource. In accordance with the Technical Rules for the Protection of


### **Table 5.**

*Evaluation of groundwater resource sensitivity in the Olifants River Basin [9–11].*

**Figure 5.** *Sensitivity groundwater.*

### *Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*

Groundwater (Protected Areas for Groundwater, W101 [15, 16]), which were drawn up in Germany, by the DVGW, together with LAWA, a protection zone of 500 m around each borehole was defined, in this study, for the project area.

In **Figure 5**, areas with the classification "high" resource sensitivity are depicted in red, those with "medium" resource sensitivity are depicted in orange and those with "low" resource sensitivity are depicted in green.

### *2.2.2 Contamination potentials of land uses*

Distinction is made between the following possible contamination potentials:


In the following sub-chapter, the contamination potential from diffuse sources, through infiltration of agricultural contaminants into groundwater, will be discussed.

For the different land use classes in the Olifants River Basin, contamination potential through infiltration of nutrients into groundwater, is assumed. **Figure 6** depicts land cover and its classification, based on the South African National Land-Cover Database [17]. The nutrient availability potential is differentiated, according to different land cover classes, analysed by Moolman [18], for the Olifants River Basin (see **Table 6**).

In a next step, the results were divided into three contamination potential classes. Areas with a "high" nutrient available potential are depicted in red, those with a "medium" nutrient availability potential are depicted in orange and those with "low" nutrient availability potential are depicted in green (see **Figure 7**).

**Figure 6.** *Land cover (72 classes) [17].*


### **Table 6.**

*Contamination potential land use classes [18].*

### **Figure 7.**

*Contamination potential of diffuse sources, due to infiltration of agricultural contaminants into groundwater.*

*Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*


### **Table 7.**

*Groundwater contamination risk through infiltration of agricultural contaminants.*

### **Figure 8.**

*Groundwater contamination risk due to infiltration of agricultural contaminants into groundwater.*

### *2.2.3 Groundwater contamination risk*

The groundwater contamination risk classification, is the result of aggregating the aforementioned groundwater resource sensitivity and the corresponding contamination potential.

**Table 7** represents the aggregation method used to establish the contamination risk for groundwater resources, from agriculture. These contamination risks are classified as "very high", "high", "medium" and "low".

**Figure 8** depicts the groundwater contamination risk in the Olifants River Basin. The contamination risk of areas depicted in 44 red is "high", the contamination risk of areas depicted in orange is "medium" and areas depicted in green have a "low" contamination risk.

Overall, the results for the Olifants River Basin shows large areas with an increased contamination risk. Vast areas with an increased contamination risk are highly relevant for water supply (boreholes) management interventions. A reduction of the contamination risk, for example through water protection concepts, is necessary.

### **3. Conclusions and outlook**

The discussed methodology was developed and applied, under different boundary conditions, in several river basins in Vietnam and South Africa.

Depending on the available information and data, the methods used to evaluate the water resources quantity and quality, were adapted to the different boundary conditions. The methods were also integrated into the existing spatial water and land use planning concepts.

This methodology is found to be suitable for the identification of problems and need for action, at the regional level and as an orientation for sub regional/subbasin levels, as well as water management units, with their local investigations and measurements protocols.

The thematically-oriented collection of geodata, related to water and land use, will create a centralized geodatabase, in which all relevant information will be available, across varying institutions and disciplines.

The described methodology analyses and compares water demands and water resources, in detail, as well as sensitivities of water resources and contamination potentials. Results of the methodology, define existing and expected problems and needs for action, on a river basin and sub-basin level, with regard to the availability of water resources and pollution risks.

The application of the methodology will enable stakeholders to make decisions, on a scientific basis. The identification process enables decision makers to attend effectively to the issues with high priority ratings first.

The close cooperation with the Vietnamese and South African authorities, within the projects, ensures a holistic implementation of the different methods on a local level. The participation of the responsible water agencies, on national level, guarantees a sustainable adjustment and a nation-wide transferability of the methods.

The derived results, from the developed methods, are documented in several reports and documents [4, 19–21]. This publication has outlined the methodology developed. Further publications show concrete applications for planning support at the regional level in Vietnam and in South Africa. This refers to the main planning maps (see **Table 8**), related explanations and recommendations for measures (monitoring, use restrictions, sanitation, etc.).

In addition, the GIS-based methods were transferred to web-based GIS systems. The software tools complement the sustainable use of the methodology. They


### **Table 8.**

*Outcome: main GIS-based updatable planning maps.*

### *Regional Water and Land Use Planning: Systematic Planning Support DOI: http://dx.doi.org/10.5772/intechopen.102713*

facilitate easy-to-use, standardized and quality-assured techniques for updating data and integrating new data. In a user-friendly way, the software tools also make the planning maps available, countrywide, through a web browser.

The main users of the methods and systems should be, for example, institutions for coordination of regional planning or river basin organizations. The web-based systems developed provide an important comprehensive information basis. Based on this, decision-makers can make decisions in a transparent and comprehensible manner.

### **Author details**

Harro Stolpe1 \*, Nguyen Ngoc Ha2 and Christian Jolk<sup>3</sup>

1 EE+E—Environmental Engineering and Environment, Ruhr-University of Bochum, Bochum, Germany

2 NAWAPI—National Center of Water Resources Planning and Investigation, Hanoi, Vietnam

3 Technische Hochschule Ostwestfalen-Lippe, Höxter, Germany

\*Address all correspondence to: harro.stolpe@rub.de

© 2022 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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[2] Jolk C, Zindler J, Stolpe H, Zindler B, Wössner R, Abecker A. Planning and decision support tools for integrated water resource management on the river basin level in South Africa using the example of the Middle Olifants subbasin. In: Prof. Dr.-Ing. Dr. rer. Pol. Dr. h. c. K.-U. Rudolph: MOSA integrated water resources management in the "Middle Olifants" river basin, South Africa – Phase II Summary Report. IEEM gGmbH: Schriftenr. Umwelttechnik u. Umweltmanagement. 2016;**34**(1):17-73

[3] Stolpe H et al. Regional Planning in the Mekong Delta – The System: Freshwater, Saline Water, and Land Uses Determines – Planning Questions – The R&D Project ViWaT-Mekong-Planning Develops Planning Support Tools. Vietnam: Hanoi; 2021. Available from: https://watersecurity.info/wp-content/ uploads/2021/04/WSCC\_ BookofAbstracts\_2021.pdf

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### **Chapter 2**
