Profiling residential water users’ routines by eigenbehavior modelling

Developing effective demand-side management strategies is essential to meet future residential water demands, pursue water conservation, and reduce the costs for water utilities. The effectiveness of water demand management strategies relies on our understanding of water consumers’ behavior and their consumption habits and routines, which can be monitored through the deployment of smart metering technologies and the adoption of data analytics and machine learning techniques. This work contributes a novel modeling procedure, based on a combination of clustering and principal component analysis, which allows performing water users’ segmentation on the basis of their eigenbehaviors (i.e., recurrent water consumption behaviors) automatically identified from smart metered consumption data. The approach is tested against a dataset of smart metered water consumption data from 175 households in the municipality of Tegna (CH). Numerical results demonstrate the potential of the method for identifying typical profiles of water consumption, which constitute essential information to support residential water demand management

PROCESS BASED CLASSIFICATION OF SEDIMENT CONNECTIVITY AT THE RIVER BASIN SCALE.

Novel modelling approaches allow to trace the fate of sediment contributions from individual river reaches throughout the river network and to assess the resulting sediment connectivity at the basin scale. The derived information is an unprecedented source of information to assess from where and over which times a downstream river reach recruits its sediment. This information links strongly to the reach sensitivity to anthropic disturbance or restoration efforts. In this paper, we demonstrate how to make the complex data-sets resulting from basin scale connectivity models accessible for river basin management applications. We introduce the concept of “connectivity signatures” that epitomizes the timing, magnitude, and quality (grain size) domain of connectivity at the reach scale. We use data driven classification techniques to identify a reduced set of typical connectivity classes. Spatial distribution of connectivity classes reveals that these classes represent specific, functional “connectivity styles” with specific locations and functions for sediment routing in the river network. Results concretize the interpretation of sediment connectivity from an operational perspective and open the way for its application to large river basins

Benefits and challenges of using smart meters for advancing residential water demand modeling and management: a review

Over the last two decades, water smart metering programs have been launched in a number of medium to large cities worldwide to nearly continuously monitor water consumption at the single household level. The availability of data at such very high spatial and temporal resolution advanced the ability in characterizing, modeling, and, ultimately, designing user-oriented residential water demand management strategies. Research to date has been focusing on one or more of these aspects but with limited integration between the specialized methodologies developed so far. This manuscript is the first comprehensive review of the literature in this quickly evolving water research domain. The paper contributes a general framework for the classification of residential water demand modeling studies, which allows revising consolidated approaches, describing emerging trends, and identifying potential future developments. In particular, the future challenges posed by growing population demands, constrained sources of water supply and climate change impacts are expected to require more and more integrated procedures for effectively supporting residential water demand modeling and management in several countries across the world

Partitioning the impacts of streamflow and evaporation uncertainty on the operations of multipurpose reservoirs in arid regions

Ongoing changes in global climate are expected to alter the hydrologic regime of many river basins worldwide, expanding historically observed variability as well as increasing the frequency and intensity of extreme events. Understanding the vulnerabilities of water systems under such uncertain and variable hydrologic conditions is key to supporting strategic planning and design adaptation options. In this paper, we contribute a multiobjective assessment of the impacts of hydrologic uncertainty on the operations of multipurpose water reservoirs systems in arid climates. We focus our analysis on the Dez and Karoun river system in Iran, which is responsible for the production of more than 20% of the total hydropower generation of the country. A system of dams controls most of the water flowing to the lower part of the basin, where irrigation and domestic supply are strategic objectives, along with flood protection.We first design the optimal operations of the system using observed inflows and evaporation rates. Then, we simulate the resulting solutions over different ensembles of stochastic hydrology to partition the impacts of streamflow and evaporation uncertainty. Numerical results show that system operations are extremely sensitive to alterations of both uncertainty sources. In particular, we show that in this arid river basin, long-term objectives are mainly vulnerable to inflow uncertainty, whereas evaporation rate uncertainty mostly affects short-term objectives. Our results suggest that local water authorities should properly characterize hydrologic uncertainty in the design of future operations of the expanded network of reservoirs, possibly also investing in the improvement of the existing monitoring network to obtain more reliable data for modeling streamflow and evaporation processes

A convex optimization approach for automated water and energy end use disaggregation

A detailed knowledge of water consumption at an end-use level is an essential requirement to design and evaluate the efficiency of water saving policies. In the last years, this has led to the development of automated tools to disaggregate high resolution water consumption data at the household level into end use categories. In this work, a new disaggregation algorithm is presented. The proposed algorithm is based on the assumption that the disaggregated signals to be identified are piecewise constant over the time and it exploits the information on the time-of-day probability in which a specific water use event might occur. The disaggregation problem is formulated as a convex optimization problem, whose solution can be efficiently computed through numerical solvers. Specifically, the disaggregation problem is treated as a least-square error minimization problem, with an additional (convex) penalty term aiming at enforcing the disaggregate signals to be piece-wise constant over the time. The proposed disaggregation algorithm has been initially tested against household electricity data available in the literature. The obtained results look promising and similar results are expected to be obtained for water data

Improving the Protection of Aquatic Ecosystems by Dynamically Constraining Reservoir Operation Via Direct Policy Conditioning

Water management problems generally involve conflicting and non-commensurable objectives. Assuming a centralized perspective at the system-level, the set of Pareto-optimal alternatives represents the ideal solution of most of the problems. Yet, in typical real-world applications, only a few primary objectives are explicitly considered, taking precedence over all other concerns. These remaining concerns are then internalized as static constraints within the problem's formulation. This approach yields to solutions that fail to explore the full set of objectives tradeoffs. In this paper, we propose a novel method, called direct policy conditioning (DPC), that combines direct policy search, multi-objective evolutionary algorithms, and input variable selection to design dynamic constraints that change according to the current system conditions. The method is demonstrated for the management problem of the Conowingo Dam, located within the Lower Susquehanna River, USA. The DPC method is used to identify environmental protection mechanisms and is contrasted with traditional static constraints de fining minimum environmental flow requirements. Results show that the DPC method identifies a set of dynamically constrained control policies that overcome the current alternatives based on the minimum environmental flow constraint, in terms of environmental protection but also of the primary objectives

Climate change awareness, perceived impacts, and adaptation from farmers’ experience and behavior: a triple-loop review

Individuals and communities socially construct risk, and societies with greater risk perception may be more apt to mobilize or adapt to emergent threats like climate change. Increasing climate change awareness is often considered necessary in the first stages of the adaptation process to manage its impacts and reduce overall vulnerability. Since agriculture is affected by climate change in several ways, farmers can provide first-hand observations of climate change impacts and adaptation options. This paper aims to identify the current research trends and set the future research agenda on climate change awareness, perceived impacts, and adaptive capacity from farmers’ experiences and behavior. We analyzed a portfolio of 435 articles collected from WoS and Scopus databases between 2010 and 2020 using bibliometrics. From the original portfolio, we select 108 articles for a more comprehensive and systematic review. Publication trends and content analysis have been employed to identify influential work, delineate the mental structure of farmers’ beliefs and concerns, and identify main research gaps. The comprehensive analysis reported (1) farmers’ socio-demographic characteristics influencing farmers’ perceptions; (2) awareness and changing climate evidence due to human activity; (3) the main perceived effects (rising temperatures, changing rainfall patterns, and extreme events); (4) the most relevant adaptation measures (crop changing and soil/water conservation techniques); and (5) factors and barriers limiting adaptation (lack of information, credit, and expertness). The review outlines the main gaps and their drivers to help future researchers, managers, and decision-makers to prioritize their actions according to farmers’ concerns and their adaptive capacity to reduce farming vulnerability

Scenario-based model predictive control of water reservoir systems

The optimal operation of water reservoir systems is a challenging task involving multiple conflicting objectives. The main source of complexity is the presence of the water inflow, which acts as an exogenous, highly uncertain disturbance on the system. When model predictive control (MPC) is employed, the optimal water release is usually computed based on the (predicted) trajectory of the inflow. This choice may jeopardize the closed-loop performance when the actual inflow differs from its forecast. In this work, we consider - for the first time - a stochastic MPC approach for water reservoirs, in which the control is optimized based on a set of plausible future inflows directly generated from past data. Such a scenario-based MPC strategy allows the controller to be more cautious, counteracting droughty periods (e.g., the lake level going below the dry limit) while at the same time guaranteeing that the agricultural water demand is satisfied. The method's effectiveness is validated through extensive Monte Carlo tests using actual inflow data from Lake Como, Italy.Comment: Modeling, Estimation and Control Conference, Lake Tahoe, Nevada, USA, October 2-5 202