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Delft, Netherlands

Crochemore L.,IRSTEA | Ramos M.-H.,IRSTEA | Pappppenberger F.,European Center for Medium Range Weather Forecasts | Van Andel S.J.,Institute for Water Education | Wood A.W.,U.S. National Center for Atmospheric Research
Bulletin of the American Meteorological Society | Year: 2016

A role-playing approach to better understand the challenges of using monthly probabilistic forecasts in sequential decision-making in water management. © 2016 American Meteorological Society.

Bateganya N.L.,University of Natural Resources and Life Sciences, Vienna | Nakalanzi D.,Institute for Water Education | Babu M.,National Water and Sewerage Corporation | Hein T.,University of Natural Resources and Life Sciences, Vienna
Environmental Technology (United Kingdom) | Year: 2015

In many sub-Saharan Africa municipalities and cities, wastewater is discharged with limited or no treatment at all, thus creating public and environmental health risks. This study assessed the performance of a conventional municipal wastewater treatment plant (WWTP), based on effluent pollution flux, in Masaka Municipality, Uganda. Also, the downstream pollution attenuation through a natural wetland was analysed to ascertain its role in buffering the WWTP performance deficits. Generally, there was deficiency in WWTP performance, with 100% failure over a five-year assessment period, for example, the mean effluent biochemical oxygen demand (BOD)5 and chemical oxygen demand (COD) concentrations (mgl-1) were found to be 316 ± 15 and 582 ± 28 compared with 50 and 100 maximum permissible environment discharge limits, respectively. Despite these deficits in WWTP performance, the wetland buffer effectively reduced pollutant loads for suspended solids (73%), organic matter (BOD5, 88% and COD, 75%), nutrients (total nitrogen, 74% and total phosphorus, 83%) and pathogens (faecal coliforms, 99%). These findings underpin the challenge of managing municipal wastewater using centralized mechanical WWTPs in the region. However, the wetland buffer system demonstrated a critical role these ecosystems play in abating both pulse and intermittent pollution loads from urban environments of sub-Saharan Africa whose sanitation systems are defective and inadequate. Therefore, it was concluded that integrating wetland ecosystems in urban planning as natural landscape features to enhance municipal wastewater management and pollution control is paramount. © 2015 Taylor and Francis.

Gersonius B.,Institute for Water Education | Ashley R.,Institute for Water Education | Pathirana A.,Institute for Water Education | Zevenbergen C.,Institute for Water Education | Zevenbergen C.,Technical University of Delft
Proceedings of the Institution of Civil Engineers: Engineering Sustainability | Year: 2010

An increasing lack of stationarity in environmental phenomena and hence in the predictability of loading and effects makes it necessary to modify the traditional approach for planning and risk assessment of flood mitigation. The traditional approach attempts to manage the flooding system with the use of predictive/optimisation methods. These use the 'most likely' or average future projection to identify a singular optimal adaptation strategy. Because the planning and risk management in this method is often decoupled from the dynamics and uncertainty of the flooding system, this is a rather risky approach. This paper argues that responsible climate adaptation requires an alternative approach that attempts to assess and manage the resiliency of the flooding system for long-term future change. The aim of such an approach is to keep the system within a configuration of states that gives at least acceptable functioning despite the occurrence of possible changes. The paper proposes an options planning and assessment process for managing the resiliency of the flooding system to climate change. This process explicitly acknowledges the uncertainty in future climate conditions by introducing and implementing flexibility (real options) into the designed components of the flooding system.

Ridolfi E.,University of Rome La Sapienza | Servili F.,University of Rome La Sapienza | Magini R.,University of Rome La Sapienza | Napolitano F.,University of Rome La Sapienza | And 2 more authors.
Procedia Engineering | Year: 2014

Pressure determination in water distribution systems (WDS) is important because it generally drives the operational actions for leakage and failure management, backwater intrusion and demand control. This determination would ideally be done through pressure monitoring at every junction in the distribution system. However, due to limited resources, it is only possible to monitor at a limited number of nodes. To this end, this work explores the use of an Artificial Neural Network (ANN) to estimate pressure distributions in a WDS using the available data at the monitoring nodes as inputs. The optimal subset of monitoring nodes are chosen through an entropy-based method. Finally, pressure values are compared to synthetic pressure measures estimated through a hydraulic model. © 2014 The Authors.

Liotta F.,University of Cassino and Southern Lazio | Chatellier P.,University Paris Est Creteil | Esposito G.,University of Cassino and Southern Lazio | Fabbricino M.,University of Naples Federico II | And 4 more authors.
Environmental Technology (United Kingdom) | Year: 2015

The role of total solids (TS) content in anaerobic digestion of selected complex organic matter, e.g. rice straw and food waste, was investigated. A range of TS from wet (4.5%) to dry (23%) was evaluated. A modified version of the Anaerobic Digestion Model No.1 for a complex organic substrate is proposed to take into account the effect of the TS content on anaerobic digestion. A linear function that correlates the kinetic constants of three specific processes (i.e. disintegration, acetate and propionate up-take) was included in the model. Results of biomethanation and volatile fatty acids production tests were used to calibrate the proposed model. Model simulations showed a good agreement between numerical and observed data. © 2014 Taylor and Francis.

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