Many regions around the world experience both chronic and intermittent needs for residents to reduce their water consumption. Recent advances in water metering infrastructure offer opportunities to provide customers with detailed feedback about their consumption, but research in behavioral science suggests that feedback by itself is not enough to motivate conservation. The current empirical work builds on previous studies showing the ability of an augmented feedback approach to promote reductions in residential water consumption, and extends previous research by exploring the variability in responses to this feedback. A sample of Sacramento customers was provided with printed home water reports in which they could see their household water consumption compared with similar homes in their area. The results showed that households that received the report used 8.35% less water in the subsequent 6 months than did similar households that did not receive the printed reports. Additional analyses showed that the effect was particularly strong for high-consuming households, and that the discrepancy between household consumption and similar homes influenced the amount of water savings.

Advanced metering infrastructure (AMI) allows for hour-by-hour monitoring of water usage and has created new opportunities to communicate with customers. This article summarizes the results from a large-scale deployment of an AMI system with more than 85,000 residential customers. Households were provided with access to a secure customer online portal where they could view their consumption information, use a leak detection algorithm to monitor their consumption patterns, and set alerts when a potential leak was detected. Analyses showed that, subsequent to signup, households that accessed the customer portal were less likely to have a leak, and when a leak did occur, they repaired it more quickly, compared with similar households that did not sign up for online access. The results provide strong evidence for the value of leak detection analytics and alerts at minimizing water loss and damage due to leaks.Water leaks are of critical interest to both water utilities and consumers. Water leaks range from small losses, such as slow-dripping faucets (<1 gph) to moderate losses from sources like toilets or irrigation lines (~1-10 gph) to large leaks from broken pipes and water lines (upward of 100 gph). Water leaks can often go undetected for long periods of time, resulting in mounting damage and wasted water. Property damage and insurance claims resulting from water damage each year are considerable, and for water-stressed regions of the world, leaks represent a major source of wasted water.With regard to residential water consumption, the Water Research Foundation (2016) estimates that 12% of all indoor water use in the United States is lost to leaks. Smart water meters can monitor and detect leaks on the basis of anomalous flow patterns, especially continuous water flow. In instances in which water flows continuously over a 24 h period, there is a high probability of a leak. Alerting residents to possible leaks can potentially spur quicker repairs and result in reduced water loss and less property damage (Britton et al. 2013). However, to date, few systematic studies have directly tested strategies for communicating leak detection to residents.While an estimated 12% of water is lost to leaks, it is not clear how much of the water loss is due to small versus large leaks. Estimates for the number of residential accounts that have a leak vary widely and depend on the size of the leak threshold. The US Environmental Protection Agency estimates that 10% of households have leaks of ≥90 gpd (≥3.75 gph; WaterSense 2017). For smaller leaks of <1 gph, estimates often exceed 50% of residential accounts. Water leaks also tend to follow seasonal trends, with higher leak rates during summer months, primarily associated with outdoor landscape irrigation. To aid in detection and repair, water utilities across the country typically conduct leak surveys to estimate water losses across their service territory, and many utilities provide their customers with free or discounted leak assessments. THE CURRENT STUDYThe current study repor...

ESL is a new Continuous System Simulation Language (CSSL) which is being developed under contract from the European Space Agency. It is based on the concepts outlined in Reference 6. The main features of the new language are:(1) Models can be built from submodels(2) Separation of model and experiment(3) Advanced discontinuity-handling (4) A parallel segment feature. The implementation of ESL requires both an interpreter and a translator version of the language. The interpreter translates the user's program into an intermediate code (H-code) which is then interpreted at run-time. The translator may be used to convert the H-code to FORTRAN-77 to produce a more efficient executable program of production runs. The entire system (with the exception of a few low-level routines) is being written in A prototype version of the language was installed in August 1983 and is currently undergoing evaluations. Details of this version are given with examples of its use.

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In the conclusion of the paper "Solving Stiff Differen tial Equations in the Simulation of Physical Systems (Simulation, Aug. 1981) T.D. Bui states, "The results ... show that LSTIFF is much more effective and reliable than the well-known GEAR program." This statement could be misleading to readers who are not familiar with stiff integration methods, and the main purpose of this note is to clarify this point.