Scientific Results

This catalogue is obtained by conducting a systematic literature review of scientific studies and reviews related to monitoring, forecasting, and simulating the inland water cycle. The analysis maps scientific expertise across research groups and classifies findings by the type of inland water studied, application focus, and geographical scope. A gap analysis will identify missing research areas and assess their relevance to policymaking.

ID ▲ Type Year Authors Title Venue/Journal DOI Research type Water System Technical Focus Abstract Link with Projects Link with Tools Related policies ID
publications-4651 article 1990 Griffin, Ronald C. and Griffin, Ronald C. and Chan, Chang and Chang, Chan Pretest analyses of water demand in thirty communities Water Resources Research 10.1029/wr026i010p02251 Using 3 years of monthly data for 30 carefully selected Texas communities, several characteristics of community water demand are investigated. The average price versus marginal price specification issue is examined in the same manner as preceding literature and again demonstrates the superiority of the average price approach. More original contributions identify (1) the need to include sewer rates in water demand models, (2) the importance of studying seasonal demand rather than annual demand, (3) seasonal variations in the price elasticity of demand, and (4) an interesting index for relating monthly community water demand to monthly climatic conditions.
publications-4652 article 1990 Goulter, I. C. and Goulter, Ian C. and Bouchart, F. J.-C. and Bouchart, Francois Reliability‐Constrained Pipe Network Model Journal of Hydraulic Engineering 10.1061/(asce)0733-9429(1990)116:2(211) A new methodology for incorporating reliability considerations directly into least‐cost optimization design models for looped water distribution networks is presented. The essence of the methodology is the measurement of reliability and making changes to the distribution system if the reliability is found to be unsatisfactory. The optimization model constrains the probability of pipe failure for each link and the probability of demand exceeding design values at each node for a fixed flow pattern in the network. The probabilities of pipe failure and demand exceedance are combined into a single reliability measure, the probability of no node failure. Due to the relationship between changing pipe breakage rates and pipe capacity, changing the demand exceedance probability also tends to reduce the probability of pipe failure. On the basis of earlier work, a simple reduction in the probability of the node demand exceeding the design values, through increasing the severity of the design flow, is used to achieve...
publications-4653 article 1990 Walski, Thomas M. and Walski, Thomas M. and Walski, Thomas M. and Walski, Thomas M. Sherlock Holmes Meets Hardy‐Cross: or Model Calibration in Austin, Texas Journal American Water Works Association 10.1002/j.1551-8833.1990.tb06933.x One would think that water distribution model calibration would be a straightforward, logical process. Sometimes, however, the best tools for model calibration consist of a lot of detective work, a little intuition, and just a pinch of luck. Some anecdotes on model calibration in Austin, Texas, illustrate this principle
publications-4654 article 1991 Chandapillai, Jacob and Chandapillai, Jacob Realistic Simulation of Water Distribution System Journal of Transportation Engineering-asce 10.1061/(asce)0733-947x(1991)117:2(258) Due to financial constraints in developing countries, water supply to various consumers is quite less than actual demand. A technique for simulation of water distribution network duly considering this low supply situation is presented. This is accomplished by satisfying an additional constraint of head-flow relationship at each node. The conventional methods just give the resulting pressures at various nodes in the prescribed demand condition. This is meaningless in a low-supply situation. The proposed method gives actual supply quantity from each node based on inherent characteristics of the system. The practical advantages are also discussed.
publications-4655 article 1992 Cullinane, M. John and Cullinane, M. John and Lansey, Kevin and Lansey, Kevin E and Mays, Larry W. and Mays, Larry W. Optimization-availability-based design of water-distribution networks Journal of Hydraulic Engineering 10.1061/(asce)0733-9429(1992)118:3(420) A practical measure for water‐distribution system reliability, based on hydraulic availability is presented and incorporated in an optimal design procedure for component sizing. The measure combines hydraulic and mechanical availability in a form that defines the proportion of the time that the system will satisfactorily fulfill its function. However, rather than a simple discrete failure relationship with absolute failure if pressure heads fall below a prescribed minimum the hydraulic availability is modeled with continuous increasing acceptability as higher pressures occur. Availability is considered in a nonlinear optimization model that is. reduced in complexity by linking the optimizer with a network solver to implicitly solve the hydraulic constraints. The results of the model application show an increasing marginal cost for higher levels of availability, and the optimal designs tend to follow the engineering rules of thumb for system design.
publications-4656 article 1993 Berk, Richard A. and Berk, Richard A. and Schulman, Daniel and Schulman, Daniel and McKeever, Matthew and McKeever, Matthew and Mckeever, Matthew and Freeman, Howard E. and Freeman, Howard E. Measuring the impact of water conservation campaigns in California Climatic Change 10.1007/bf01091831 The reductions in water use achieved by urban households in California during the recent drought are well documented. What is not documented is how those reductions were achieved. In this paper, we report on survey data from the Los Angeles and San Francisco Bay Areas describing the water conservation activities undertaken. We also examine variation in water conservation activities across households and adjust statistically for social desirability biases in the self-reports.
publications-4657 article 1995 Clark, Robert M. and Clark, Robert M. and Rossman, Lewis A. and Rossman, Lewis A. and Wymer, Larry and Wymer, Larry J. Modeling Distribution System Water Quality: Regulatory Implications Journal of Water Resources Planning and Management 10.1061/(asce)0733-9496(1995)121:6(423) Passage of the Safe Drinking Water Act in 1974 and its Amendments in 1986 (SDWAA) is changing the way water is treated and delivered in the United States. Under the SDWAA the U.S. Environmental Protection Agency (EPA) is required to regulate chemical contaminants and pathogenic microorganisms in drinking water. Emphasis has shifted from a primary concern with treated drinking water to attainment of standards at the point of consumption. Two regulations promulgated under the SDWAA, the Surface Water Treatment Rule (SWTR) and the Total Coliform Rule (TCR) specify treatment and monitoring requirements that must be met by all public water suppliers. This paper will examine the effect of various system variables on chlorine residual propagation. A recently proposed model (EPANET) will be utilized to examine the extent of fluid velocity and pipe radius on chlorine demand. The effect of these variables on the maintenance of chlorine residuals will be demonstrated. It will be shown that the same variables that affect the propagation of chlorine residual levels can potentially affect disinfection efficacy and the formation of disinfection by–products.
publications-4658 article 1998 Bousquet, François and Bousquet, François and Bakam, Innocent and Bakam, Innocent and Proton, Hubert and Proton, Hubert and Page, Christophe Le and Page, Christophe Le Cormas: Common-Pool Resources and Multi-agent Systems 10.1007/3-540-64574-8_469 This paper describes a simulation environment, called Cormas, that relies on multi-agent systems and has been achieved in Smalffalk, using VisualWorks software. Such a simulation tool may prove useful to better understand the complex interactions between natural and social dynamics when studying renewable resource management. The general principles of the Cormas platform are first presented, then the implementation is described. Two models built with Cormas allow to illustrate the use and the genericity of this tool.
publications-4659 article 1998 Billings, R. Bruce and Billings, R. Bruce and Agthe, Donald E. and Agthe, Donald E. STATE-SPACE VERSUS MULTIPLE REGRESSION FOR FORECASTING URBAN WATER DEMAND Journal of Water Resources Planning and Management 10.1061/(asce)0733-9496(1998)124:2(113) State-space and multiple regression methods were compared with each other and with simple monthly averages for the accuracy of their short-term forecasts of urban water demand. Seven sets of 24 monthly forecasts of water demand were computed. Each set is based on a different 7-year historic period, using a total of 15 years of monthly data. Based on a variety of measures of forecast error, the state-space models exhibited less bias than the other models, whereas the size of a typical forecast error was about the same for state-space and simple monthly averages. Forecast errors showed considerable variability within both state-space and multiple regression. The mean absolute forecast error ranged from 7.4 to 14.8\% for multiple regression, and from 3.6 to 13.1\% for state-space. For this sample data, the multiple regression model forecasts were least accurate and also had larger biases than the other methods.
publications-4660 article 1999 Barthélemy, Marc and Barthelemy, Marc and Barthelemy, Marc and Amaral, Luı́s A. Nunes and Amaral, Luís A. Nunes Small-World Networks: Evidence for a Crossover Picture Physical Review Letters 10.1103/physrevlett.82.3180 Watts and Strogatz [Nature (London) 393, 440 (1998)] have recently introduced a model for disordered networks and reported that, even for very small values of the disorder $p$ in the links, the network behaves as a ``small world.'' Here, we test the hypothesis that the appearance of small-world behavior is not a phase transition but a crossover phenomenon which depends both on the network size $n$ and on the degree of disorder $p$. We propose that the average distance $\ensuremath{\ell}$ between any two vertices of the network is a scaling function of $n/{n}^{*}$. The crossover size ${n}^{*}$ above which the network behaves as a small world is shown to scale as ${n}^{*}(p\ensuremath{\ll}1)\ensuremath{\sim}{p}^{\ensuremath{-}\ensuremath{\tau}}$ with $\ensuremath{\tau}\ensuremath{\approx}2/3$.