Application of Operations Research Techniques for Allocation of Water Resources in Utah

In this report a methodology is described for determining the optimal allocation of water supplies in the State of Utah to minimize the cost of meeting an assumed set of water requirements. A linear programming model was formulated to represent the ten interconnected hydrologic study areas of the state. The comprehensive model considers virtually all uses, areas, sources, transfers and costs of water. The model has 204 constraints and 3378 variables and was solved by the simplex method. Included in the results are the following: the optimal water allocation or the groundwater, surface water, and water transfers which minimize the cost; the shadow prices of the resources; sensitivity analyses to identify the critical cost coefficients in the optimal solution; parametric analyses to test the effects of changing constraints; and manipulations of the model to test other factors such as operating rules, legal policies, political and institutional limitations. The tabulated data were carefully condensed so as to be more easily understood. Flow diagrams and graphs summarize the important information. The work is fully documented so others can follow what was done and improve the method or apply the model to other areas

Goal-oriented a posteriori error estimation for the travel time functional in porous media flows

In this article we consider the a posteriori error estimation and adaptive mesh refinement for the numerical approximation of the travel time functional arising in porous media flows. The key application of this work is in the safety assessment of radioactive waste facilities; in this setting, the travel time functional measures the time taken for a non-sorbing radioactive solute, transported by groundwater, to travel from a potential site deep underground to the biosphere. To ensure the computability of the travel time functional, we employ a mixed formulation of Darcy's law and conservation of mass, together with Raviart-Thomas H(div) conforming finite elements. The proposed a posteriori error bound is derived based on a variant of the standard Dual-Weighted-Residual approximation, which takes into account the lack of smoothness of the underlying functional of interest. The proposed adaptive refinement strategy is tested on both a simple academic test case and a problem based on the geological units found at the Sellafield site in the UK

TRADING POULTRY LITTER AT THE WATERSHED LEVEL : A GOAL FOCUSING APPLICATION

We explore the transfer of poultry litter among watersheds incorporating both economic characteristics (litter demand and supply) and environmental characteristics (vulnerability to phosphorus runoff, a major pollutant). A combination of techniques was employed: the Lemunyon-Gilbert P-Index model to determine watershed environmental vulnerability, GIS for land use coverages, and a goal focusing model (incorporating Saaty's eigen-value approach for penalty weight estimation) to identify optimal litter shipments among watersheds. Both primary and secondary data were used. The results should be useful to producers and policy makers in the study area and in other areas where poultry production is linked to water quality, and contribute to a more sustainable poultry sector.Livestock Production/Industries,

PHYSICAL AND ECONOMIC MODEL INTEGRATION FOR MEASUREMENT OF THE ENVIRONMENTAL IMPACTS OF AGRICULTURAL CHEMICAL USE

Environmental Economics and Policy,

Methodology for the optimal management design of water resources system under hydrologic uncertainty

Un sistema de gestión de sequías apropiado requiere de la anticipación de los posibles efectos que un episodio de este tipo tenga sobre el sistema de recursos hídricos. Esta tarea sin embargo resulta más complicada de lo que parece. En primer lugar, debido al alto grado de incertidumbre existente en la predicción de variables hidrológicas futuras. Y en segundo, debido al riesgo de sobrerreacción en la activación de medidas de mitigación generando falsa sensación de escasez, o sequía artificial. A este respecto, los planes especiales de sequía proveen de herramientas para la gestión eficiente de situaciones con escasez de recursos y la preparación de cara a futuros eventos. De todos modos, las diferentes estrategias de operación seguidas en cada sistema de recursos hídricos hacen que las herramientas que en algunos casos resultaron altamente útiles no lo sean tanto cuando se aplican en sistemas distintos. Debido a la falta de tiempo y/o al exceso de confianza en los trabajos realizados por terceros, con excelentes resultados en sus respectivos casos, a veces se cae en el error de implementar metodologías no del todo apropiadas en sistemas con requisitos completamente distintos. El desarrollo y utilización de metodologías generalizadas aplicables a diferentes sistemas y capaces de proporcionar resultados adaptados a cada caso es, por tanto, muy deseable. Este es el caso de las herramientas de modelación de sistemas de recursos hídricos generalizadas. Estas permiten homogeneizar los procesos mientras siguen siendo los suficientemente adaptables para proporcionar resultados apropiados para cada caso de estudio. Esta tesis presenta una serie de herramientas destinadas a avanzar en el análisis y comprensión de los sistemas de recursos hídricos, haciendo énfasis en la prevención de sequías y la gestión de riesgos. Las herramientas desarrolladas incluyen: un modelo de optimización generalizado para esquemas de recursos hídricos, con capacidad para la representación detallada de cualquier sistema de recursos hídricos, y una metodología de análisis de riesgo basada en la optimización de Monte Carlo con múltiples series sintéticas. Con estas herramientas es posible incluir tanto la componente superficial como la subterránea del sistema estudiado dentro del proceso de optimización. La optimización está basada en la resolución iterativa de redes de flujo. Se probó la consistencia y eficiencia de diferentes algoritmos de resolución para encontrar un balance entre la velocidad de cálculo, el número de iteraciones, y la consistencia de los resultados, aportando recomendaciones para el uso de cada algoritmo dadas las diferencias entre los mismos. Las herramientas desarrolladas se aplican en dos casos de estudio reales en la evaluación y posibilidad de complementación de los sistemas de monitorización y alerta temprana de sequías existentes en los mismos. En el primer caso, se propone un enfoque alternativo para la monitorización de la sequía en el sistema de operación anual del río Órbigo (España), complementándolo con la utilización de la metodología de análisis de riesgo. En el segundo caso, las herramientas se emplean en un sistema con una estrategia de operación completamente distinta. Se estudia como el análisis de riesgo de la gestión óptima puede ayudar a la activación anticipada de los escenarios de sequía en los sistemas de los ríos Júcar y Turia, cuya operación es hiperanual. En esta ocasión, el sistema de indicadores existente goza de una gran confianza por parte de los usuarios. La metodología de análisis de riesgo es, sin embargo, capaz de anticipar los eventos de sequía con mayor alarma, aspecto que es deseable si se quiere evitar que los episodios en desarrollo vayan a más. En ambos casos se muestra como la evaluación anticipada de las posibles situaciones futuras del sistema permiten una definición confiable de los escenarios de sequía con suficiente antelación para la activación efectiva de medidas de prevención y/o mitigación en caso de ser necesarias. La utilización de indicadores provenientes de modelos frente a indicadores basados en datos observados es complementaria y ambos deberían utilizarse de forma conjunta para mejorar la gestión preventiva de los sistemas de recursos hídricos. El empleo de modelos de optimización en situaciones de incertidumbre hidrológica es muy apropiado gracias a la no necesidad de definir reglas de gestión para obtener los mejores resultados del sistema, y teniendo en cuenta que las reglas de operación habituales pueden no ser completamente adecuadas en estas ocasiones.Haro Monteagudo, D. (2014). Methodology for the optimal management design of water resources system under hydrologic uncertainty [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/45996TESI

New directions in water resources management: The role of water pricing policies

Water resources will face increasing competition and higher environmental concerns during this century. To meet these challenges, the new Water Framework Directive has drawn up an integrated framework and established the basic principles for a sustainable water policy in the European Union. The introduction of water prices reflecting the true cost of irrigation is one of its most innovative components. In this paper, a positive mathematical programming model is developed to assess the environmental and socio-economic impacts of water pricing policies in Spanish irrigated lands. The model interface allows friendly use and easy replication in a large number of irrigation districts, selected throughout the Spanish territory. The model results show the impact on environmental indicators, water consumption, cropping patterns, technology adoption, labor, farmers' income, and the water agency revenues when different scenarios of cost recovery are considered. It is argued that this modeling approach may be used as a management tool to assist in the implementation of the cost recovery approach of the new Water Framework Directive

Optimizing Conjunctive Use of Groundwater and Surface Water

Mathematical models for groundwater and surface-water systems are formulated and solved on a digital computer using linear programming for optimizing the water use of the system. Post-optimal analysis, including sensitivity analysis of the objective function coefficients and right-hand side terms, is also applied to the models. The models which are developed include a general deterministic model, a general stochastic model in which hydrologic inputs are allowed to be probabilistic, and models of two simple, but real, river basins. The advantages of linear programming analysis are demonstrated by the computer solutions which can be obtained by this method of optimization. The method is shown to be effective as a guide to optimal water resources systems design and planning

Groundwater Development in Arid Basins

Summary: Groundwater development frequently provides a means whereby tremendous new economic opportunities are opened up. If supplies are overdrawn (mined) the ensuing regional economy may be able to affort replacements from more costly sources. In the United States the Salt River Valley of Arizona and the valleys of California provide examples. Two cases are treated in this paper, Israel and West Pakistan. In Israel, besides furnishing more than half of the basic source of water suppply, groundwater development provides opportunity for both quantity and quality management, which makes possible use of surface supplies and reclaimed sewage as firm rather than marginal sources. This development will permit the total water resources of this small country, where agricultural production ranks among the world\u27s most efficient, to be utilized effectively down to almost the last drop by the mid 1970\u27s. Israel must then look to desalted water from the sea for further expansion of its overall water supply. In West Pakistan a combination of level terrain and leaky canals since about 1890 led to threatened waterlogging and salinity of more than 25 million acreas of irrigated land, even though supplies were less than half adequate for good productivity. By the 1950\u27s low yields and increasing population threatened starvation. However, initiation of groundwater development, first by the government and later by pricate entreprise, has, since 1960, let to construction of 3,500 governmental tube wells of about 3 cfs capacity and 30,000 private tube wells of slightly less than 1 cfs capacity. Results have been dramatic. Agricultural production and use of fertilizer are rapidly increasing, and opening of well development of pricate enterprise is providing the irrigator with benefits of free competition for his water custom which he did not previously enjoy. Ultimately, besides providing full supplies for an estimated 26 to 30 million acrea, drainage and salinity problems will be mitigated if about 50 million acre-feet are pumped each year from groundwater including about 28 million acre-feet to be mined from a reserve of about 1,900 million acre-feet. With some difficult surface storage development due to terrain, mining may eventually be reduced. Through an eventual technological solution for the continuing overdraft is not now in sight, perhaps an economy may be built which can affort such a solution when the time comes

The green revolution and the productivity paradox : evidence from the Indian Punjab

The author provides district-level estimates of the contribution of technical change to agricultural output growth in the Indian Punjab from 1960 to 1993. Contrary to widespread belief, productivity growth in the Punjab was surprisingly low during the green revolution (in the mid-1960s), when modern hybrid seed varieties were being adopted. It improved later, after adoption of the new varieties was essentially complete. The author proposes three reasons for this pattern: (1) The standard measure of total factor productivity overstates the contribution of capital to output growth at the expense of the productivity residual. High-yielding varieties introduced in the 1960s helped spur output growth by making crops responsive to water and fertilizer, which not only allowed but indeed encouraged far greater use of capital inputs. This increase in the elasticity of the output response to capital inputs is incorporated into the index of factor accumulation and therefore excluded from the measure of total factor productivity growth. As a result, the contribution of technical change to growth in Punjab's agriculture during the green revolution is probably underestimated. (2) The overstatement of the capital contribution during the green revolution is exacerbated by indivisibilities in capital inputs. (3) Productivity growth did not come from the adoption of modern varieties alone. Improved resource management and public investment in infrastructure also helped improve productivity.Crops&CropManagement Systems,Economic Theory&Research,Agricultural Research,Water Conservation,Environmental Economics&Policies,Crops&Crop Management Systems,Agricultural Research,Environmental Economics&Policies,Economic Theory&Research,Economic Growth