Hydraulic Performance Evaluation of Community-Managed Irrigation Scheme, North Shewa, Amhara, Ethiopia

Background: Irrigation scheme performance assessment is vital to evaluate the impacts of irrigation practices, to identify performance gaps and to improve system performances. However, irrigation performance assessment has not been carried out for Yelen irrigation scheme since its operation. Therefore, this study has been done with the purpose of identifying and understanding the current level of irrigation performance of Yelen irrigation scheme. The indicators of adequacy, efficiency, dependability, deficiency and equity were used to determine hydraulic performance. Primary data were collected through flow measurement using current meter and Parshall flume, transect walk, household surveys and group discussions, whereas Secondary data were collected from different sources. CROPWAT 8.0 model, SPSS, Microsoft excels and GIS software was used to analyze the data. Water delivery indicators were evaluated from the amounts of water which was actually applied and which should have been applied.Results: According to the results of the study, the value of adequacy, dependability, efficiency, deficiency and equity were found to be 0.84, 0.26, 0.93, 0.17and 0.34 respectively. Generally, the performance of the irrigation system is poor. It mainly resulted due to water scarcity, illegal water abstraction, sedimentation of canals and inadequate operation and maintenance provisions.Concussions: Therefore, adequate maintenance and suitable management approaches are required to improve the irrigation system performance. Under the water scarce situations, improving the performance of water delivery systems can offer an opportunity to realize field level water savings.

Securing the Environmental Water Requirements of Seasonally Ponding Wetlands: Partnering Science and Management Through Benefit Sharing

Although environmental flow regime assessments are becoming increasingly holistic, they rarely provoke water managers to enact the adaptive water reallocation mechanisms required to secure environmental water for wetlands. The conditions that cause science-based environmental flow assessments to succeed or fail in informing the management of environmental water requirements remain unclear. To begin to resolve these conditions, we used process tracing to deconstruct the sequence of activities required to manage environmental water in four case studies of seasonally ponding wetlands in Mediterranean and Mesoamerican watersheds. We hypothesized that, when the flexibility and equitability of the socioeconomic system do not match the complexity of the biophysical system, this leads to a failure of managers to integrate scientific guidance in their allocation of environmental water. Diagnostic evidence gathered indicates that science-management partnerships are essential to align institutional flexibility and socioeconomic equitability with the system’s ecohydrological complexity, and thus move from determination to reallocation of environmental water. These results confirm that institutions e.g., river basin organizations need to be supplemented by motivated actors with experience and skill to negotiate allocation and adaptive management of environmental water. These institutional-actor synergies are likely to be especially important in water scarce regions when the need to accommodate extreme hydrological conditions is not met by national governance capacity. We conclude by focusing on benefit sharing as a means to better describe the conditions for successful science-based environmental flow assessments that realize productive efficiency in environmental water allocation i.e., recognition of multiple values for both people and ecosystems.

Sustainable water resources management under water-scarce and limited-data conditions

Urbanization and population growth increase the demand for freshwater abstraction, food production, rising thus the agricultural, economic, and productivity expectations. The need for improved water services, sustainable and resilient management under changing climate, are major drivers to set forth the redesigning of water planning. Water scarcity combined with the limited expansion of new infrastructure create competition among water uses and further stress the satisfactory coverage of the increasing needs. Integrated modeling is a way to simulate and address the above challenges, however, poor monitoring, incomplete databases, and complexity make its applications difficult. Questions such as what data to use, how to best exploit the (limited) available databases, what parameters to calculate, and how to satisfy both economic and environmental objectives, occur. This study presents a novel Decision Support System (DSS), combining hydrology, economics, engineering, and social aspects, aimed to participatory management, using simple concepts, and discussing assumptions for working with limited data, and useful parameters to estimate. Water availability and demand, water quality, profits, costs, and management scenario analysis, including nature-based solutions, are explored under climate change scenarios, and alternative policies are evaluated. The combination of the above and the useful modeling insights, under water- and data-scarcity conditions are novel elements, while the aim is to encourage integrated and sustainable water resources management through understandable and user-friendly DSSs.

Interbasin water transfer in a changing world: A new conceptual model

Water scarcity is a global issue, affecting in excess of four billion people. Interbasin Water Transfer (IBWT) is an established method for increasing water supply by transferring excess water from one catchment to another, water-scarce catchment. The implementation of IBWT peaked in the 1980s and was accompanied by a robust academic debate of its impacts. A recent resurgence in the popularity of IBWT, and particularly the promotion of mega-scale schemes, warrants revisiting this technology. This paper provides an updated review, building on previously published work, but also incorporates learning from schemes developed since the 1980s. We examine the spatial and temporal distribution of schemes and their drivers, review the arguments for and against the implementation of IBWT schemes and examine conceptual models for assessing IBWT schemes. Our analysis suggests that IBWT is growing in popularity as a supply-side solution for water scarcity and is likely to represent a key tool for water managers into the future. However, we argue that IBWT cannot continue to be delivered through current approaches, which prioritise water-centric policies and practices at the expense of social and environmental concerns. We critically examine the Socio-Ecological Systems and Water-Energy-Food (WEF) Nexus models as new conceptual models for conceptualising and assessing IBWT. We conclude that neither model offers a comprehensive solution. Instead, we propose an enhanced WEF model (eWEF) to facilitate a more holistic assessment of how these mega-scale engineering interventions are integrated into water management strategies. The proposed model will help water managers, decision-makers, IBWT funders and communities create more sustainable IBWT schemes.

Willingness to Pay for Irrigation Services in the Cold Winter Deserts of Uzbekistan

Irrigation facilities in the cold winter deserts (CWDs) of Uzbekistan are very traditional and poorly managed, resulting in low water use efficiency and low productivity. Improving the irrigation facilities in these deserts is a key priority for the country. This study intended to contribute towards the development of the irrigation systems through identification and quantification of the relative implicit values smallholder farmers confer to the key characteristics of irrigation facilities. We elicited preferences with discrete choice experiments, estimated willingness to pay for these attributes using random parameters logit models, and analyzed heuristics in the choice process using a series of latent class models. Our results show that farmers have clear preferences for higher watering frequency and no interest in sharing irrigation water with downstream users. We also observed that there are distinct groups of farmers with comparable but different levels of preference. The development of irrigation facilities in the water-scarce parts of Uzbekistan would benefit from careful consideration of the preferences of the target communities and targeting of the schemes based on the broad heterogeneities within the communities. This will aid in the maintenance of irrigation systems and, as a result, increase agricultural production and productivity.

Effect of soil and crop management practices on sodicity stress alleviation and rice productivity under water scarce condition

The prominent issue faced by the farmers of Cauvery Delta regionin Tamil Nadu particularly Tiruchirapalli District is the lack of timely release of water for rice nursery preparation and transplanting. Hence wet seeding of rice is recommended for timely cultivation. On the other hand, sodic nature of the soil warrants rice cultivation only. Therefore, the present investigation was carried out to study the different soil and crop management practices on alleviating sodicity stress and improving rice (variety ADT 3) productivity under water-scarce conditions. The experiment was laid in a split plot design with six mainplots,including rice wet seeding, daincha (Sesbania aculeata) application as green manure, anti-oxidant microbial consortia (AOMC) spray and four sub-plots with graded levels of NPK based on soil test values with three replication. Results showed that the daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 125 % soil test based NPK had significantly increased thechlorophyll content, SPAD values, proline content and grain and straw yields which remained on par with daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 100 % soil test based NPK.Significantly lower ESP at 5% level and higher phosphatase activity in soil was also recorded by daincha incorporation @ 6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 125 % and 100 % soil test based NPK. Gross return, net return and B:C ratio were also higher in the plot, which received daincha incorporation @6.25 t/ha followed by rice wet seeding + AOMC spray @1.5 % with 100 % soil test based NPK. The present study reveals that the inclusion of ectophytic microbial population spray in rice plants and the management practices helps the crop to tolerate the sodicity stress under water-scarce condition by maintaining required physiological functions like proline synthesis and enzyme activities etc which need to be further explored at the genotypic level.

Drinking Water Insecurity in Southwest Coastal Bangladesh: How Far to SDG 6.1?

Substantial progress has been seen in the drinking water supply as per the Millennium Development Goals (MDG), but achieving the Sustainable Development Goals (SDG), particularly SGD 6.1 regarding safely managed drinking water with much more stringent targets, is considered as a development challenge. The problem is more acute in low-income water-scarce hard-to-reach areas such as the southwest coastal region of Bangladesh, where complex hydrogeological conditions and adverse water quality contribute to a highly vulnerable and insecure water environment. Following the background, this study investigated the challenges and potential solutions to drinking water insecurity in a water-scarce area of southwest coastal Bangladesh using a mixed-methods approach. The findings revealed that water insecurity arises from unimproved, deteriorated, unaffordable, and unreliable sources that have significant time and distance burdens. High rates of technical dysfunction of the existing water infrastructure contribute to water insecurity as well. Consequently, safely managed water services are accessible to only 12% of the population, whereas 64% of the population does not have basic water. To reach the SDG 6.1 target, this underserved community needs well-functioning readily accessible water infrastructure with formal institutional arrangement rather than self-governance, which seems unsuccessful in this low-income context. This study will help the government and its development partners in implementing SDG action plans around investments to a reliable supply of safe water to the people living in water-scarce hard-to-reach coastal areas.

Enhancing the Method of Decentralized Multi-Purpose Reuse of Wastewater in Urban Area

The reuse of treated wastewater is attractive as a communal source of excess water source in water-scarce counties and nations. The expansion of the urban population and the increase in the coverage of water supply networks and sewage networks will raise the amount of municipal sewage. This can turn into a new-fangled water resource. In the current research, the new campus city was selected as the first case study to design a wastewater reuse and recycling system. Accordingly, one of the most important innovations in the proposed research is the unique applied dimensions, in addition to its first-time performance, and the application of the Geo-land method in wastewater recycling as the theoretical dimension of the design. Clustering the decentralized reuse of wastewater for urban areas showed that significant parts of residential areas are located in the first high priority group. Urban planners can consider the results in establishing a comprehensive plan to prioritize the decentralized use of wastewater in the urban area.

The consecutive disparity of precipitation in conterminous Spain

Precipitation irregularity constitutes a constraint for natural systems and socio-economic activities, particularly in water-scarce environments. Standard variability statistics such as the standard deviation, variance, and coefficient of variation do not consider the chronological order of these values. In Climatology, however, the temporal order of meteorological events is a relevant factor that can affect natural and socio-economic systems. In order to evaluate the disparity between consecutive values in precipitation series, we applied the Consecutive Disparity Index (D) to the monthly grid with the highest spatial resolution (10×10 km) existing in Peninsular Spain for the period December 1915–November 2015. Monthly, seasonal, and annual D values show an increase from north to southwest, especially in July and August. The D values for the month-to-month correlative series and for monthly mean precipitation reveal a relatively similar pattern. In the latter case, however, the low values are recorded towards southern Spain, following some mountain ranges in the Centre-East of the territory. Monthly, seasonal, and annual precipitation values are also negatively correlated with the corresponding D values.