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Groundwater resources are shared across management boundaries. Multiple management units that differ in scale, constraints and objectives may manage a shared resource in a decentralized approach. The interactions among water managers, water users, and the water resource components influence the performance of management strategies and the resilience of community-level water supply and groundwater availability. This research develops an agent-based modeling (ABM) framework to capture the dynamic interactions among household-level consumers and policy makers to simulate water demands. The ABM is coupled with a groundwater model to evaluate effects on the groundwater table. The framework is applied to explore trade-offs between improvements in water supply sustainability for local resources and water table changes at the basin-level. A group of municipalities are simulated as agents who share access to a groundwater aquifer in Verde River Basin, Arizona. The framework provides a holistic approach to incorporate water user, municipal, and basin level objectives in evaluating water reduction strategies for long-term water resilience.

We determined reference hydro-climatic and land use/cover sensitivities of stormwater runoff and quality in the Miami River Basin of Florida by developing a dynamic rainfall-runoff model with the EPA Storm Water Management Model. Potential storm runoff in the complex coastal-urban basin exhibited high and notably different seasonal sensitivities to rainfall; with stronger responses in the drier early winter and wetter late summer months. Basin runoff and pollutant loads showed moderate sensitivities to the hydrologic and land cover parameters; imperviousness and roughness exhibited more dominant influence than slope. Sensitivity to potential changes in land use patterns was relatively low. The changes in runoff and pollutants under simultaneous hydro-climatic or climate-land use perturbations were notably different than the summations of their individual contributions. The quantified sensitivities can be useful for appropriate management of stormwater quantity and quality in complex urban basins under a c...

Much research has been conducted to quantify stormwater runoff and quality using both mechanistic (i.e. process-based) and empirical (i.e. data-driven) techniques. Mechanistic models generally include the mathematical representation of relevant physico-chemical processes to generate storm runoff quantity and quality. Empirical approaches analyse available data for potential response and predictor variables to trace the interactions of major processes and develop data-driven explanatory and/or predictive relationships. This paper reviews major, mostly unresolved, challenges with both mechanistic and empirical modelling of stormwater, sheds light on the scientific gaps with conventional practices, and offers important perspectives by taking the highly urbanized Miami River Basin of Florida as an analytical example. Appreciating the varying levels of process complexity in different urban river basins, we discuss the relative applicability of mechanistic and empirical methods for robust predictions of stormwater quantity and quality. Copyright © 2013 John Wiley & Sons, Ltd. RESUME Beaucoup de recherches ont ete menees pour quantifier les eaux pluviales generees par les tempetes, et leur qualite. Elles utilisent a la fois des techniques mecaniques (basees sur les processus) et empiriques (deduites des donnees). Les modeles mecanistes comprennent generalement la representation mathematique des processus physico-chimiques pertinentes pour generer la quantite et la qualite des eaux de ruissellement en condition de tempete. Les approches empiriques analysent les donnees disponibles pour que potentiellement les variables de reponse et les variables predictives retracent les interactions entre les processus majeurs, et developpent des relations explicatives et/ou predictives pilotees par les donnees. Ce document passe en revue les principaux defis, pour la plupart non resolus, avec la modelisation a la fois mecaniste et empirique des eaux pluviales; il met en lumiere les lacunes scientifiques avec les pratiques conventionnelles et offre d'importantes perspectives en prenant comme exemple d'analyse le tres urbanise bassin de la riviere Miami, en Floride. En appreciant le niveau de complexite variable des processus dans des differents bassins hydrographiques urbains, nous avons discute de l'applicabilite relative des methodes mecanistes et empiriques pour des predictions robustes de la quantite et de la qualite des eaux pluviales. Copyright © 2013 John Wiley & Sons, Ltd.

response of reinforced concrete columns under lateral load has always been an area attracting research and practical interest. The importance of columns in building frame in terms of lateral stiffness has been subjected to growing attention in relation to soft storey phenomena and other seismic response analysis over times. Various numerical approaches has been attempted to correlate deflection with lateral load according to theories and field performance. A numerical analysis has been carried out in this study on column behavior subjected to lateral load. Cantilever columns have been modeled using finite element analysis package ANSYS considering non linear stress-strain relationship of concrete and bilinear behavior of steel. Effect of lateral reinforcement in terms of confinement has also been associated. For simplicity of analysis, only rectangular columns with single story height have been considered. The results have been compared with field experimental data. The response of load-deflection curve to change in column geometry has also been discussed. The load deflection curve found in this manner is almost linear with constant stiffness initially as suggested by ACI in the elastic zone. However stiffness gradually decreases in the plastic zone and finally tends to zero. Column response to change in column geometry is also according to the prescribed relations in ACI. Increase in stiffness has been found with decrease in height and increase in cross section. Finally the test results are compared with field experimental value where they show almost similar behavior.

Growing population centers in the arid southwest increase the demand for water, which is typically met through increased groundwater withdrawals. Hydro-climatic extremes due to climate change may also increase demands and decrease the replenishment of groundwater supply. Groundwater aquifers typically cross watershed, municipal, and management boundaries, and as a result, multiple diverse agencies manage a shared resource. Municipalities and management districts define individual demand management strategies that adapt water consumption to falling groundwater levels. The interactions among governing agencies, consumers, and the environment influence the performance of local management strategies and the availability of regional groundwater resources. This research develops an agent-based modeling (ABM) framework to analyze the dynamic interactions among changing water demands and limited groundwater resources under the stresses of population growth and climate change scenarios. Households are initialized as agents with properties and attributes to define indoor water use, outdoor water use, and water use reduction. Policy-maker agents are encoded to represent governing agencies that mandate or encourage water use restrictions. Demand management strategies are simulated as the response of a policy-maker agent to groundwater levels, safe yield, and climate variables. The framework is applied for municipalities located in the Verde River Basin, Arizona that withdraw groundwater from the Verde Formation-Basin Fill-Carbonate aquifer system. The effects of management strategies on water savings and basin-wide groundwater levels are explored, based on water use demands and reductions in different sectors of municipal water use. Insights gained through this simulation study can be used to guide groundwater policy-making under changing hydro-climatic scenarios for a long-term planning horizon.