Assessment of data-driven modeling strategies for water delivery canals

Conferência: CONTROLO’2012 - 16-18 July 2012 - FunchalThe aim of this work is to develop nonlinear dynamical models for the canal system of Núcleo de Hidráulica e Controlo de Canais. The canal is a nonlinear system and thus should be modeled to meet given operational requirements, while capturing all relevant system dynamics, such as the resonance waves created due to the movements of gates, and also contributing to the controller precision. The nonlinear modeling is based on data-driven methods, namely Composite Local Linear Models, Fuzzy Models and Artificial Neural Networks. These models are identified using data collected from the experimental facility, and their performance is assessed based on suitable validation criteria. The modeling results show the effectiveness of these models while capturing all significant dynamics for the canal system

Generic typology for irrigation systems operation

Irrigation management / Irrigation systems / Water use efficiency / Canals / Operations / Typology / Water delivery / Water distribution / Water conveyance / Water storage / Irrigation effects / Environmental effects / Gravity flow / Hydraulics / Constraints / Water supply / Networks / Case studies / Sri Lanka

USCID fourth international conference

Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.In response to a range of internal and external drivers and the need to protect the district's pre-1914 water rights, Oakdale Irrigation District (OID) developed a long-term Water Resources Plan (WRP). The 100-year-old irrigation district provides irrigation and domestic water service to over 55,000 acres in California's San Joaquin Valley. The study effort created a strategic roadmap for the implementation of a $170 million capital program focused on protecting OID's water rights while meeting the changing needs of its constituency and serving the region. The second phase included programmatic environmental documentation, which is being followed by design and construction of facility improvements. This multi-disciplined effort included detailed land use modeling, water balance modeling, on-farm surveys, a comprehensive infrastructure assessment, and the development of a phased infrastructure plan to rehabilitate and modernize an out-of-date system. The approach also integrated water right evaluations, groundwater studies, development and evaluation of program alternatives, financial analyses, environmental compliance, and public outreach. Key benefits resulting from WRP implementation include protecting the district's water rights, increasing reliability during droughts, and modernizing a century-old system to meet the needs of its current and future customer base. Implementation includes a balanced effort of water transfers and expansion of service into OID's sphere of influence while keeping water rates affordable. OID's infrastructure will be rebuilt, modernized, and expanded, and customer service and water use efficiency will be enhanced

Engineering and water governance interactions in smallholder irrigation schemes for improved water management.

Masters Degree, University of KwaZulu-Natal, Durban.Smallholder Irrigation Schemes (SISs) in South Africa have reported below expectation performance, despite massive investments. A diagnosis of the SISs poor performance indicates prevalence of infrastructural deficiencies, as well as poor institutional setup. The government’s Irrigation Management Transfer (IMT) initiative compounds the problem. IMT placed irrigators in self-governance, which inadvertently made irrigators carry the burden of scheme Operation and Maintenance (O&M) costs. This study sought to investigate and evaluate how technical design principles i.e., technical aspect of irrigation design, interact with irrigation water governance for SISs in KwaZulu-Natal Province. The study hypothesized that the existing current water control infrastructure does relate to the water governance frameworks in the selected study sites. The study was carried out in Tugela Ferry Irrigation Scheme (TFIS) and Mooi-River Irrigation Scheme (MRIS). An infrastructure condition assessment was carried out followed by a root cause analysis. Questionnaires were then administered to relevant stakeholders to rate the degree of identified causal factors. Key informants ranked how water governance and infrastructure aspects are related. The data was processed using a fuzzy theory approach. Finally, structured questionnaires were administered to irrigators to establish how water governance impacted on water adequacy for crop production. A binary logit regression model was employed to process the data. Assessments revealed the poor condition of the infrastructure, such as deep cracks in canals and missing latches on hydrants. The study revealed that TFIS had a strong institutional setups according to the Closeness Coefficients( = 0.18), and clearly defined goals and objectives for the scheme operation. However, other governance aspects such as procedures ( = 0.17, = 0.16) were not strong. MRIS ( = 0.20) had a good standing on rules and regulations as compared to TFIS ( = 0.14). Eight water governance related statistically significant variables that influenced water adequacy were identified. The eight variables were irrigation scheme ( = 0.000), location of plot within the scheme ( = 0.008), training in water management ( = 0.012), satisfaction with irrigation schedule ( = 0.000), irrigation training ( = 0.085), farmer knowledge of governments aims in SIS ( = 0.012), availability of water licenses ( = 0.002), and water fees ( = 0.022). A descriptive analysis showed that 24% and 86% of the farmers in MRIS and TFIS respectively, had adequate water. The study concluded that the SISs lacked an O&M plan and the farmers were not willing to opt for collective action and iii cooperate in Water Users Association (WUAs) and Irrigation Management Committees (IMCs). Some of the water governance aspects were discordant with infrastructure characteristics and requirements, consequently, impacting on the water adequacy for the irrigators. Overall, the study proved the hypothesis that the water control infrastructure does not relate with the water governance framework. This study recommends that the stakeholders involved in SISs, i.e., government, extension workers, NGOs, should aid the irrigators in policy articulation. In addition, the WUA and IMCs should provide incentives to motivate farmers to actively participate in scheme O&M

Impacts of Colombia's current irrigation management transfer program

Privatization / Irrigation management / Irrigated farming / Policy / Costs / Economic aspects / Operations / Maintenance / Agricultural production

Coupling hydrological and irrigation schedule models for the management of surface and groundwater resources in Khorezm, Uzbekistan

The irrigated agriculture in the Khorezm region of Uzbekistan is characterized by huge water withdrawals from the Amu Darya River. The vast infrastructure built for extensive irrigation, together with inappropriate drainage infrastructure, leads to a build-up of very shallow groundwater (GW) levels, followed by waterlogging and salt accumulation in the soil profile. Previous studies revealed deficits in the management and maintenance institutions, inappropriate and inflexible irrigation strategies, poor linkages between field level demands, and in the operation of the network. No flexible water management tool is currently in use that, by pre-conceiving mitigation strategies, would aim at reducing the current yield reductions. This study aimed to develop and introduce such a tool at the irrigation scheme level, illustrated at the example of the Water Users Association (WUA) Shomakhulum in Khorezm (about 2,000 ha of farmland). The tool can support managerial decisions on optimization of water use, particularly under the deficitary water supply predicted under climate change. Remote Sensing (RS) techniques (SEBAL) were used in combination with real-time hydrological measurements (e.g., ponding experiments to estimate losses in canals) to assess the operational performance of the WUA. Delivery performance ratio (DPR), relative evapotranspiration (RET), depleted fraction (DF), drainage ratio (DR), overall consumed ratio (OCR), field application ratio (FAR) and conveyance ratio (CR) were used as performance indicators. Using the current and target values for FAR and CR, three improved irrigation efficiency scenarios were developed (S-A: baseline or business-as-usual (BAU), S-B: improving CR; S-C: raising FAR; S-D: improving FAR and CR together). Recharge to the aquifer was determined for these scenarios by the water balance approach. Spatial dynamics of GW levels and soil characteristics (factors that affect recharge) were represented by dividing the WUA into ‘hydrological response units’. The FEFLOW-3D model was used to simulate GW dynamics under the scenarios. Recharge rates—through which the scenarios impact on GW— were a major input to this model. Simulated GW levels served in turn as an input to the HYDRUS-1D model used to estimate the capillary rise contribution of the GW to water demands of the key crops cotton, winter wheat and vegetables. The daily capillary rise was in turn fed into the CROPWAT model to simulate optimal irrigation scheduling (IS) and different water management scenarios. This novel hierarchical coupling of RS/GIS with the FEFLOW, HYDRUS and CROPWAT models was applied to the WUA area for an optimal management of surface and GW. Operational performance of the irrigation system under BAU is very poor. Although RET (0.82) is near to target value (0.75), a DPR >1 indicates inefficient use of the supplied water. The FAR shows that under BAU 57 % of the delivered water is lost during application. The values of DF (0.4), OCR (0.51) and DR (0.55) do not match target values postulated in the literature, suggesting severe flaws in water distribution. Results of the water balance model show that the average recharge to the WUA under BAU (4 mm d-1) can be reduced to 3.4, 1.8 and 1.4 mm d-1 in S-B, S-C and S-D, respectively. FEFLOW simulations show that improvements in irrigation efficiency alone can lower the GW levels by 12 cm (S-B), 38 cm (S-C) and 44 cm (S-D) compared to the BAU. Furthermore, HYDRUS-1D modeling shows that GW contributes up to 19% to the WUA’s total water requirement under BAU. This would be reduced to 17, 11 and 9 % for S-B, S-C and S-D, respectively, leading to lower salt accumulation but higher net irrigation requirements. Simulated IS under BAU shows a 7 % (official IS) and 41.6 % (farmers’ practice) reduction in cotton yield from the optimum IS. To mitigate adverse effects of water scarcity, the optimal IS was developed assuming 25 and 50 % reduced surface water supplies. Minimum yield losses with 25 % reduced water supply will be in the range of 10-20 %, and with water reduction of 50 % will be up to 22-30 %. Three water saving scenarios (WSS-1: introducing crops of low water demand, WSS-2: leaving marginal land out, and WSS-3: improving the irrigation efficiency) were introduced. Water savings of 9, 20 and 41 % can be achieved for WSS-1, WSS-2 and WSS-3, respectively. The results of the study provide important guidelines for the water management institutes in the region.Die Kopplung hydrologischer Bewässerungssteuerungsmodelle mit Bewässerungssteuerungsmodellen für die Bewirtschaftung von Oberflächen- und Grundwasserressourcen in Khorezm, Usbekistan Ausgedehnte Bewässerungsanlagen und hohe Wasserentnahmen aus dem Fluss Amu Darya kennzeichnen die Bewässerungswirtschaft in Khorezm/Usbekistan. Die dadurch in Verbindung mit unzureichender Entwässerung verursachten sehr hohen Grundwasserstände führen zu Vernässung und begünstigen die Bodenversalzung. Bisherige Studien belegen Defizite der für Betrieb und Unterhaltung der Systeme zuständigen Institutionen, unangemessene und starre Bewässerungsstrategien und eine unzureichende Abstimmung zwischen Feldwasserbedarf und Systembetrieb. Es fehlt ein flexibles Bewässerungssteuerungsmodell, das die Erarbeitung vorausschauender Strategien zur Verringerung von Ertragseinbußen ermöglicht. Die vorliegende Arbeit zielt auf die Entwicklung und Anwendung eines solchen Modells für die Wassernutzereinheit (WUA) Schomachulum in Choresm/Usbekistan (2000 ha bewässerte Fläche). Das Modell soll Optimierungsentscheidungen des Wassermanagements unterstützen, insbesondere für den Fall von Dargebotsengpässen, durch globale Klimaänderungen. Fernerkundungstechniken (SEBAL-Algorithmus: potenzielle und aktuelle Evapotranspiration) wurden mit hydrologischen Messungen kombiniert (ponding-Verfahren: Wasserverluste in Kanälen), um die Effizienz des Bewässerungsbetriebs einzuschätzen. Als Indikatoren dienten delivery performance ratio (DPR), relative evapotranspiration (RET), depleted fraction (DF), drainage ratio (DR), overall consumed ratio (OCR), field application ratio (FAR) and conveyance ratio (CR). Derzeitige Beträge und Zielwerte für FAR und CR wurden benutzt, um 3 Szenarien mit verbesserten Wirkungsgraden zu entwickeln (S-A: Ausgangssituation; S-B: verbesserter CR; S-C: erhöhter FAR; S-D: Kombination verbesserter CR und erhöhter FAR). Die Auswirkungen der Szenarien auf die Grundwasserneubildung wurden mit einem Wasserbilanzansatz abgeschätzt. Um räumliche Variabilitäten des Grundwasserstands und der Bodenverhältnisse (Faktoren auf die Grundwasserneubildung) zu berücksichtigen, wurde die WUA in homogene Untereinheiten aufgeteilt (hydrological response units). Das Grundwassermodell FEFLOW ermöglichte die Simulation der Grundwasserdynamik für die Szenarien. Die Neubildungsraten stellen dabei den Einfluss der Szenarien auf das Grundwassersystem dar. Die simulierten Grundwasserstände dienten als Eingangsgrößen in das HYDRUS-1D-Modell, das eine Quantifizierung des kapillaren Aufstiegs als Beitrag zur Deckung des Pflanzenwasserbedarfs für wesentliche Kulturen in der WUA (Baumwolle, Winterweizen, Gemüse) in Tagesschritten erlaubte. Diese gingen in das CROPWAT-Modell ein, womit optimale Bewässerungspläne für die Szenarien erarbeitet werden konnten. Die Effizienz des Bewässerungsbetriebs ist derzeit ungünstig. Obwohl RET mit 0,82 in der Nähe des Zielwertes liegt (0,75), belegt ein DPR-Wert >1 eine ineffiziente Wassernutzung. Das derzeitige Niveau des FAR zeigt, dass 57% des auf die Felder geleiteten Wassers verloren geht. Die Werte für DF (0,4), OCR (0,51) und DR (0,55) weichen von den Zielwerten (aus Literaturauswertung) ab und verdeutlichen Probleme der Wasserverteilung. Im Ausgangsszenario erreicht die durchschnittliche tägliche Grundwasserneubildung 4 mm d-1; für die Szenarien S-B, S-C und S-D ergeben sich 3,4 bzw. 1,8 bzw. 1,4 mm d-1. Die FEFLOW-Simulationen zeigen, dass die mit den Szenarien korrespondierenden Wirkungsgradverbesserungen zu Grundwasserständen führen, die um 12 cm (S-B), 38 cm (S-C) und 44 cm (S-D) unter denen der Ausgangssituation (S-A) liegen. HYDRUS ermöglicht die Einschätzung, dass derzeit 19% des Pflanzenwasserbedarfs durch den kapillaren Aufstieg gedeckt werden. Für die Szenarien ergeben sich Reduzierungen auf 17% (S-B), 11% (S-C) und 9% (S-D), was Salzakkumulation verringert aber den Nettobewässerungsbedarf erhöht. Im Vergleich mit optimierten Wasserverteilungsplänen (Simulation) führt die offizielle (Norm-basierte) Wasserverteilung zu 7% und die von Landwirten praktizierte Anwendung zu 41,6% Ertragsverlust bei Baumwolle. Das Steuerungsmodell wurde auch genutzt, um die Auswirkungen einer Unterversorgung auf den Ertrag zu minimieren. Bei einem um 25% (50%) verminderten Wasserdargebot läßt sich die Ertragseinbuße auf 10-18% (20-30%) begrenzen. Die Simulation von Wassereinsparoptionen (WSS-1: wasserextensivere Kulturen; WSS-2: Aufgabe marginaler Standorte; WSS-3: Wirkungsgradverbesserung) belegt Einsparpotentiale von 9% (WSS-1), 20% (WSS-2) und 41% (WSS-3). Die Ergebnisse der Arbeit liefern wesentliche Grundlagen für wasserwirtschaftliche Institutionen in der Region

The domestic benefits of tropical forests : a critical review emphasizing hydrological functions

The authors critically review the literature on the net domestic (within-country) economic benefits of protecting tropical forests, focusing on hydrological benefits and the production of nontimber forest products. (The review does not consider other important classes of benefits, including global benefits of all kinds, ecological benefits which do not have instrumental economic value, and the existence value of forests.) Their main conclusions: (1)The level of net domestic benefits from forest preservation is highly sensitive to the alternative land use and to local climatic, biological, geological, and economic circumstances. When the alternative use is agroforestry or certain types of tree crops, the preservation of natural forests may yield no instrumental domestic benefits. (2)The hydrological benefits from forest preservation are poorly understood and likely to be highly variable. They may also be fewer than popularly assumed: Deforestation has not been shown to be associated with large-scale flooding. Tropicaldeforestation is generally associated with higher, not lower, dry season flows. Although it is plausible that deforestation should affect local precipitation, the magnitude and even the direction of the effects are unknown, except in the special case of cloud forests that"harvest"passing moisture. The link between deforestation and downstream sediment damage is sensitive to the basic topography and geology. Where sediment transport is slow - as in large, low-gradient basins - downstream impacts may manifest themselves in the distant future, so that the net present value of damage is small. Steep basins near reservoirs or marine fisheries, on the other hand, can cause substantial damage if land cover is severely disturbed. But only a few pioneering studies have examined the economics of reservoir sedimentation, and improved models of both sediment transport and dam function are needed. (3) The most impressive point estimates of forest value based on nontimber forest products are often based on atypical cases of faulty analysis. Where domesticated or synthetic substitutes exist, the nontimber forest product-related rents for natural forests will usually be driven toward zero.Water Conservation,Roads&Highways,Wetlands,Hydrology,Environmental Economics&Policies,Water Resources Assessment,Forestry,Hydrology,Roads&Highways,Wetlands

Hydraulic simulations to evaluate and predict design and operation of the Chashma Right Bank Canal

Irrigation systems / Irrigation canals / Flow control / Velocity / Canal regulation techniques / Hydraulics / Simulation models / Design / Operations / Crop-based irrigation / Distributary canals / Water delivery / Policy / Protective irrigation / Water allocation / Water requirements / Sedimentation / Water distribution / Equity / Water conveyance / Pakistan / Chashma Right Bank Canal

Global water: issues and insights

This book brings together some of the world’s leading water researchers with an especially written collection of chapters on: water economics; transboundary water; water and development; water and energy; and water concepts. Introduction Freshwater governance holds a prominent position in the global policy agenda. Burgeoning water demand due to population growth and rising incomes is combining with supply-side pressures, such as environmental pollution and climate change, to create acute conditions of global water scarcity. This is a major concern because water is a primary input for agriculture, manufacturing, environmental health, human health, energy production and just about every economic sector and ecosystem. In addition to its importance, the management of freshwater resources is a complex, multidisciplinary topic. Encompassing a range of fields in the physical and social sciences, the task of sustainably meeting human and environmental water needs requires a depth and breadth of understanding unparalleled by most other policy problems. Our objective in this volume is to provide knowledge and insights into major issues and concepts related to freshwater governance. The book is divided into five themed parts: Economics, Transboundary governance, Development, Energy and Water Concepts. A part addresses each theme and opens with an introduction that provides an overview of key topics. For example, the introduction to the economics section presents two main foci: measuring the value of water and managing trade-offs between different water uses. The thematic case studies discuss issues such as water pricing in Organisation for Economic Co-operation and Development (OECD) countries, finance of water supply and irrigation infrastructure and improving agricultural production with enhanced water management. The aim of the volume is to accessibly communicate academic research from the many fields of freshwater governance. Too often, academic research is paywalled and/or written in a style that caters to colleagues in the same field, rather than a broader audience from other disciplines, the policy-making community and the general public. This open-access book presents the research of a range of global experts on freshwater governance in brief, insightful chapters that do not presume a high level of pre-existing knowledge of their respective subjects. This format is intended to present knowledge on the key problems of and solutions to global freshwater challenges. The final part presents research from several United Nations Educational, Social, and Cultural Organisation (UNESCO) supported water research Chairs and Centres. Support and coordination of the insititutions highlighted in this part of the book is provided by UNESCO. One water research Chair is The Australian National University – UNESCO Chair in Water Economics and Transboundary Governance, which was established in April 2010 and works with partners in southern Africa, UNESCO, the Global Water Partnership and other organisations to: (1) increase the skills, capacity, networks and potential of leaders and prospective water managers and policy-makers; (2) sustain and strengthen institutional capacity (especially in southern Africa) by providing a platform for collaboration and institutional development; and, (3) develop innovative research, tools, case-studies, and insights on water economics, water governance and equity. Established by the ANU–UNESCO Chair, the Global Water Forum (GWF) seeks to disseminate knowledge regarding freshwater governance and build the capacity of students, policy-makers and the general public to respond to local and global water issues. The GWF publishes accessible, subscription-free articles highlighing the latest research and practice concerning freshwater governance. A broad range of water-related topics are discussed in a non-technical manner, including water security, development, agriculture, energy and environment. In addition to publishing articles, reports and books, the GWF is engaged in a range of activities, such as the annual Emerging Scholars Award and hosting a portal to educational resources on freshwater. We hope that you enjoy reading this book and, more importantly, gain an improved understanding of the complex freshwater-governance challenges facing us all on a global scale and at a local level

Pro-poor intervention strategies in irrigated agriculture in Asia: poverty in irrigated agriculture: issues and options: Bangladesh

Irrigated farming / Poverty / Irrigation management / Water resource management / Policy / Planning / Institutions / Organizations / Local government / Non-governmental organizations / Legislation / Water users / Participatory management / Public sector / Water allocation / Cost recovery / Households / Income / Expenditure / Irrigation canals / Bangladesh