scholarly journals Evaluation of Irrigation Water Resources Availability and Climate Change Impacts—A Case Study of Mwea Irrigation Scheme, Kenya

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2330
Author(s):  
George Akoko ◽  
Tasuku Kato ◽  
Le Hoang Tu

Rice is an important cereal crop in Kenya, where it is mainly grown in the Mwea Irrigation Scheme, MIS. The serious challenges of MIS include low water use efficiency and limited available water resources. The objective of this study is to analyze the current and future irrigation water resource availability for the improvement of future water management. A Soil Water Assessment Tool (SWAT), a public domain software supported by the United States Department of Agriculture’s Agricultural Research Service in Bushland, TX, USA, was used to estimate the current and future water resources availability from the MIS’s main irrigation water supply sources (River Thiba and River Nyamindi). CropWat, a computer program developed by the Land and Water Division of the Food and Agriculture Organization (FAO), Rome, Italy, was used to estimate irrigation water requirements from 2013–2016 and into the future (2020–2060 and 2061–2099). Future climatic data for total available flow and irrigation requirement estimations were downloaded from three General Circulation Models (GCMs). The data was bias corrected and down-scaled (with observed data) using a Climate Change Toolkit, a toolkit for climate change analysis developed by the Water Weather and Energy Ecosystem, Zurich, Switzerland. The results indicated that the highest irrigation water deficits were experienced in July and August based on the existing cropping pattern. Under a proposed future pattern, estimates show that MIS will experience water deficits mainly from June to October and from January to February. This study recommends that MIS management should put into strong consideration the simulated future estimates in irrigation water availability for the improvement of water management.

2003 ◽  
Vol 4 (7) ◽  
pp. 35-60
Author(s):  
Luis Ernesto Cervera Gómez ◽  
Rodolfo Rubio Salas

This article aims to analyze some basic criteria for a sustainable use of water in an international watershed shared by Mexico and the United States. The study area comprises the region of Ambos Nogales, which is located inside the Upper Santa Cruz River Basin. This portion of the watershed represents the main ecosystem and the main source of water for urban and rural populations located in this region. Following criteria of sustainability the authors revise and adapt to the case of Ambos Nogales, a set of guidelines proposed by the Pacific Institute for Studies in Development, Environment, and Security. These guidelines include the following elements: basic water requirements needed to maintain quality of life in the population and the health of ecosystems; water quality that meets certain minimum standards; human actions and their impact on long-term renewability of freshwater stocks and flows; collection of data concerning water resources, use and quality of water; institutional mechanisms to prevent and resolve conflicts; and a democratic process of water-planning and decision-making. These twin cities have a long history of cooperation and conflict linked to water resources, which makes available enough information to create a diagnostic about the water management inside a binational arena, and allowing to explore possibilities for a better water resources management under a sustainable regime and from an international perspective. Keywords: Sustainability, binational water management, ambos Nogales region.


Author(s):  
Vadim Yapiyev ◽  
Kanat Samarkhanov ◽  
Dauren Zhumabayev ◽  
Nazym Tulegenova ◽  
Saltanat Jumassultanova ◽  
...  

Both climate change and anthropogenic activities contribute to the deterioration of terrestrial water resources and ecosystems worldwide. Central Asian endorheic basins are among the most affected regions through both climate and human impacts. Here, we used a digital elevation model, digitized bathymetry maps and Landsat images to estimate the areal water cover extent and volumetric storage changes in small terminal lakes in Burabay National Nature Park (BNNP), located in Northern Central Asia (CA), for the period of 1986 to 2016. Based on the analysis of long-term climatic data from meteorological stations, short-term hydrometeorological network observations, gridded climate datasets (CRU) and global atmospheric reanalysis (ERA Interim), we have evaluated the impacts of historical climatic conditions on the water balance of BNNP lake catchments. We also discuss the future based on regional climate model projections. We attribute the overall decline of BNNP lakes to long-term deficit of water balance with lake evaporation loss exceeding precipitation inputs. Direct anthropogenic water abstraction has a minor importance in water balance. However, the changes in watersheds caused by the expansion of human settlements and roads disrupting water drainage may play a more significant role in lake water storage decline. More precise water resources assessment at the local scale will be facilitated by further development of freely available higher spatial resolution remote sensing products. In addition, the results of this work can be used for the development of lake/reservoir evaporation models driven by remote sensing and atmospheric reanalysis data without the direct use of ground observations.


2021 ◽  
Author(s):  
Ronan Abhervé ◽  
Clément Roques ◽  
Laurent Longuevergne ◽  
Stéphane Louaisil ◽  
Jean-Raynald de Dreuzy ◽  
...  

<p>While it is well understood and accepted that climate change and growing water needs affect the availability of water resources, the identification of the main physical processes involved remains challenging. It notably requires to filter interannual to interdecadal fluctuations and extreme events to isolate the underlying trends. Metropolitan areas are specifically subject to growing pressures because of the significant and increasing demand, combined with the strong anthropization of land uses.</p><p>The Meu-Chèze-Canut catchment supplies the city of Rennes with drinking water (680 km² - 500 000 users, Brittany, France). In this field laboratory, we explore the dynamics of the water cycle and water resources availability. In this context, water supply is mostly coming from reservoir storage for which levels shows a medium-term vulnerability in response to frequent relatively dry years. Based on retrospective data analysis, we describe the relationship between climatic forcing (precipitation, temperature) and water availability (aquifer storage, river discharge and reservoir storage) in different parts of the catchment that are characterized by distinct lithological and topographical settings. We then evaluate the resilience of both surface and groundwater resources, their past evolution and their resilience to climate change and increasing societal needs.</p><p>Water resources availability in these catchments relies on two geological formations with distinct hydrodynamics properties: the Armorican sandstone and Brioverian schist. To assess the resilience of the system, we specifically analyzed the relationships between monthly effective precipitation and stream discharge within nine sub-catchments over the past 30 years. We observe annual hysteresis relationships - that is, a time lag between precipitation and discharge highlighting the capacity of the landscape to temporarily store water - with significant variability in shapes across the catchments. We argue that topographic and lithological factors play key roles in controlling this variability through their impacts on subsurface storage capacity and characteristic drainage timescales. We propose perspectives based on the complementary use of calibrated groundwater models to leverage these results and provide adaptive water management strategies.</p>


2020 ◽  
Vol 163 (3) ◽  
pp. 1247-1266 ◽  
Author(s):  
Hagen Koch ◽  
Ana Lígia Chaves Silva ◽  
Stefan Liersch ◽  
José Roberto Gonçalves de Azevedo ◽  
Fred Fokko Hattermann

AbstractSemi-arid regions are known for erratic precipitation patterns with significant effects on the hydrological cycle and water resources availability. High temporal and spatial variation in precipitation causes large variability in runoff over short durations. Due to low soil water storage capacity, base flow is often missing and rivers fall dry for long periods. Because of its climatic characteristics, the semi-arid north-eastern region of Brazil is prone to droughts. To counter these, reservoirs were built to ensure water supply during dry months. This paper describes problems and solutions when calibrating and validating the eco-hydrological model SWIM for semi-arid regions on the example of the Pajeú watershed in north-eastern Brazil. The model was calibrated to river discharge data before the year 1983, with no or little effects of water management, applying a simple and an enhanced approach. Uncertainties result mainly from the meteorological data and observed river discharges. After model calibration water management was included in the simulations. Observed and simulated reservoir volumes and river discharges are compared. The calibrated and validated models were used to simulate the impacts of climate change on hydrological processes and water resources management using data of two representative concentration pathways (RCP) and five earth system models (ESM). The differences in changes in natural and managed mean discharges are negligible (< 5%) under RCP8.5 but notable (> 5%) under RCP2.6 for the ESM ensemble mean. In semi-arid catchments, the enhanced approach should be preferred, because in addition to discharge, a second variable, here evapotranspiration, is considered for model validation.


2019 ◽  
Vol 20 (2) ◽  
pp. 679-687 ◽  
Author(s):  
Angelos Alamanos ◽  
Stamatis Sfyris ◽  
Chrysostomos Fafoutis ◽  
Nikitas Mylopoulos

Abstract The relationship between water abstraction and water availability has turned into a major stress factor in the urban exploitation of water resources. The situation is expected to be sharpened in the future due to the intensity of extreme meteorological phenomena, and socio-economic changes affecting water demand. In the city of Volos, Greece, the number of water counters has been tripled during the last four decades. This study attempts to simulate the city's network, supply system and water demand through a forecasting model. The forecast was examined under several situations, based on climate change and socio-economic observations of the city, using meteorological, water pricing, users' income, level of education, family members, floor and residence size variables. The most interesting outputs are: (a) the impact of each variable in the water consumption and (b) water balance under four management scenarios, indicating the future water management conditions of the broader area, including demand and supply management. The results proved that rational water management can lead to remarkable water conservation. The simulation of real scenarios and future situations in the city's water demand and balance, is the innovative element of the study, making it capable of supporting the local water utility.


Energies ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7709
Author(s):  
Günter Müller-Czygan ◽  
Viktoriya Tarasyuk ◽  
Christian Wagner ◽  
Manuela Wimmer

Water is increasingly taking center stage when it comes to coping with climate change. Especially in urban areas, negative consequences from heavy rainfall events and prolonged dry periods are rising worldwide. In the past, the various tasks of urban water management were performed by different departments that often did not cooperate with each other (water supply, wastewater disposal, green space irrigation, etc.), as the required water supply was not a question of available water volumes. This is already changing with climate change, in some cases even dramatically. More and more, it is necessary to consider how to distribute available water resources in urban areas, especially during dry periods, since wastewater treatment is also becoming more complex and costly. In the future, urban water management will examine water use in terms of its various objectives, and will need to provide alternative water resources for these different purposes (groundwater, river water, storm water, treated wastewater, etc.). The necessary technological interconnection requires intelligent digital systems. Furthermore, the water industry must also play its role in global CO2 reduction and make its procedural treatment processes more efficient; this will also only succeed with adequate digital systems. Although digitization has experienced an enormous surge in development over the last five years and numerous solutions are available to address the challenges described previously, there is still a large gap between the scope of offerings and their implementation. Researchers at Hof University of Applied Sciences have investigated the reasons for this imbalance as part of WaterExe4.0, the first meta-study on digitization in the German-speaking water industry, funded by the German Federal Ministry of Education and Research. Only 11% of roughly 700 identified products, projects and studies relate to real applications. For example, the surveyed experts of the water sector stated that everyday problems are considered too little or hardly at all in new solutions, which greatly overburdens users. Furthermore, they see no adequate possibility for a systematic analysis of new ideas to identify significant obstacles and to find the best way to start and implement a digitization project. The results from four methodologically different sub-surveys (literature and market research, survey, expert interviews and workshops) provide a reliable overview of the current situation in the German-speaking water industry and its expectations for the future. The results are also transferable to other countries.


2020 ◽  
Author(s):  
Simonetta Paloscia ◽  
Giacomo Fontanelli ◽  
Simone Pettinato ◽  
Emanuele Santi ◽  
Giuliano Ramat ◽  
...  

&lt;p&gt;This project deals with the implementation of an innovative water management system in Mediterranean countries (i.e. Tunisia and Egypt), which suffer from chronic water scarcity, together with two European countries (Germany and Italy). The consortium is developing and applying synergic methods and algorithms for investigating the water cycle, using remote sensing techniques.&lt;/p&gt;&lt;p&gt;The focus is on the use of satellite data (both optical and microwave) for monitoring vegetation cover and water status along with soil moisture temporal evolutions in order to improve the knowledge of the water cycle in arid areas. Both local and regional monitoring are carried out in order to investigate different spatial scales.&lt;/p&gt;&lt;p&gt;Environmental models and algorithms for the retrieval of hydrological parameters have been developed in the frame of this project in order to match the main goal of the project, i.e. to propose practical and cost-effective solutions for driving and updating a method for the sustainable use of water in agriculture.&amp;#160;&lt;/p&gt;&lt;p&gt;An optimized management of water resources for cultivated lands on Egyptian Delta (Northern part) and Tunisian territory will be realized by analyzing the available spatial and temporal data for the areas of interest appropriately selected for this purpose. As such, an efficient water use, equitable distribution of water resources, community participation in decisions, and sustainable system operation over time can be supported.&lt;/p&gt;&lt;p&gt;First of all, we aim to localize different crop and irrigation techniques for the study regions. This information is required as a basis for further investigations and assessments. Secondly, the water efficiency for different lands, crop types and irrigation systems will be assessed.&lt;/p&gt;&lt;p&gt;Afterwards, possible improvements in agricultural practice with respect to climate change scenarios and information on water efficiency will be determined by rating the outcome from the assessment.&lt;/p&gt;


Sign in / Sign up

Export Citation Format

Share Document