Integrated urban water modelling with uncertainty analysis

2006 ◽  
Vol 54 (6-7) ◽  
pp. 379-386 ◽  
Author(s):  
G. Mannina ◽  
G. Freni ◽  
G. Viviani ◽  
S. Sægrov ◽  
L.S. Hafskjold

In the last twenty years, the scientific world has paid particular care towards the problems that involve the environment. Accordingly, several researches were developed to describe phenomena that take place during both wet and dry periods and to increase the knowledge in this field. In particular, attention was addressed towards the problems linked with receiving water body pollution because of the impact of rain water in the urban environment. In order to obtain a good description of the problem, it is important to analyse both quantity and quality aspects connected with all the transformation phases that characterise the urban water cycle. Today, according to this point, integrated modelling approach is spreading, aiming to find solutions to improve the quality characteristics of the receiving water body. Because several models are connected together for analysing the fate of pollutants from the sources on the urban catchment to the final recipient, classical problems connected with the selection and calibration of parameters are amplified by the complexity of the modelling approach increasing the uncertainty and reducing the reliability connected with a model's application. For this reason, a parsimonious integrated modelling approach has been developed and its uncertainty has been evaluated adopting the well known GLUE framework. For the purpose of the study, the uncertainty analysis has been applied to a “semi–hypothetic” case study obtained connecting Fossolo catchment (Bologna – Italy) to the Oreto river near Palermo (Italy).

2010 ◽  
Vol 61 (9) ◽  
pp. 2381-2390 ◽  
Author(s):  
Gabriele Freni ◽  
Giorgio Mannina ◽  
Gaspare Viviani

The objective of this paper is the definition of a methodology to evaluate the impact of the temporal resolution of rainfall measurements in urban drainage modelling applications. More specifically the effect of the temporal resolution on urban water quality modelling is detected analysing the uncertainty of the response of rainfall–runoff modelling. Analyses have been carried out using historical rainfall–discharge data collected for the Fossolo catchment (Bologna, Italy). According to the methodology, the historical rainfall data are taken as a reference, and resampled data have been obtained through a rescaling procedure with variable temporal windows. The shape comparison between ‘true’ and rescaled rainfall data has been carried out using a non-dimensional accuracy index. Monte Carlo simulations have been carried out applying a parsimonious urban water quality model, using the recorded data and the resampled events. The results of the simulations were used to derive the cumulative probabilities of quantity and quality model outputs (peak discharges, flow volume, peak concentrations and pollutant mass) conditioned on the observation according to the GLUE (Generalized Likelihood Uncertainty Estimation) methodology. The results showed that when coarser rainfall information is available, the model calibration process is still efficient even if modelling uncertainty progressively increases especially with regards to water quality aspects.


Author(s):  
Yuyan Liu ◽  
Fangfang Ding ◽  
Caiye Ji ◽  
Dan Wu ◽  
Lin Wang ◽  
...  

Abstract Palladium (Pd) is widely used in vehicle exhaust catalysts (VECs) to reduce toxic emissions from motor vehicles. The study aimed to quantitatively determine Pd content and water quality parameters, to analyze the variation differences and to explore the effect of water quality parameters on Pd content in the urban water environment system (wet deposition–rainfall runoff–receiving water body–estuary) of the city of Haikou, Hainan Island, China. The method used in this study included microwave digestion under high pressure and temperature, analysis by inductively coupled plasma mass spectrometry, quality control of the experimental procedure and guaranteed recovery (85% −125%). The results showed that the dissolved Pd average content in the urban water environment system was the highest in rainfall runoff (4.93 ng/L), followed by that in the receiving water body (4.56 ng/L), and it was the lowest in wet deposition (0.1 ng/L). The suspended Pd average content was the highest in the estuary (2.83 ng/L), followed by that in rainfall runoff (1.26 ng/L), and it was the lowest in wet deposition (6 × 10−4 ng/L). The particle–water partition ratio of the estuary Pd was the highest (1.26), followed by that of Pd in rainfall runoff (0.26). The particle–water partition ratio of the wet deposition Pd was the lowest (6 × 10−3). The dissolved Pd was correlated with the pH, Cl−, and total suspended solids (TSS) (correlation coefficient = 0.52, −0.68, 0.39, p < 0.05; regression coefficient = 1.27, −1.39, 0.01). The suspended Pd was only correlated with Cl− and TSS (correlation coefficient = −0.36, 0.76, p < 0.05; regression coefficient = −1.45, 0.01). Cl− and TSS were the most closely related to Pd in the water environment system. Although individual factors such as pH, Cl−, and TSS had certain migration and transformation effects on Pd in the wet deposition–rainfall runoff–receiving water body–estuary system, the probability of strong correlations was not high. In particular, Eh was not related to the dissolved nor suspended Pd content (correlation coefficient = 0.14, 0.13), which may be due to the synergistic effect of the multiple physical factors on Pd. This study was helpful to better understand the environmental behavior of Pd and provided important theoretical support for the prevention and protection against urban water environmental pollution.


Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 946 ◽  
Author(s):  
Talita F. G. Silva ◽  
Brigitte Vinçon-Leite ◽  
Bruno J. Lemaire ◽  
Guido Petrucci ◽  
Alessandra Giani ◽  
...  

Worldwide, eutrophication and cyanobacteria blooms in lakes and reservoirs are a great concern for water resources management. Coupling a catchment hydrological model and a lake model has been a strategy to assess the impact of land use, agricultural practices and climate change on water quality. However, research has mainly focused on large lakes, while urban reservoirs and their catchments, especially in tropical regions, are still poorly studied despite the wide range of ecosystem services they provide. An integrated modelling approach coupling the hydrological model Storm Water Management Model SWMM and the lake ecological model DYRESM-CAEDYM is proposed for Lake Pampulha (Brazil). Scenarios of increased imperviousness of the catchment and of reduction in the load of nutrients and total suspended solids (TSS) in dry weather inflow were simulated. Runoff water quality simulations presented a fair performance for TSS and ammonium (NH4+) while the dynamics of total phosphorus (TP) and nitrate (NO3−) were poorly captured. Phytoplankton dynamics in the lake were simulated with good accuracy (Normalized Mean Absolute Error, NMAE = 0.24 and r = 0.89 in calibration period; NMAE = 0.55 and r = 0.54 in validation period). The general trends of growth, decline and the magnitude of phytoplankton biomass were well represented most of the time. Scenario simulations suggest that TP reduction will decrease cyanobacteria biomass and delay its peaks as a consequence of orthophosphate (PO43−) concentration reduction in the lake surface layers. However, even decreasing TP load into Lake Pampulha by half would not be sufficient to achieve the water quality objective of a maximum concentration of 60 µg chla L−1. Increased imperviousness in the catchment will raise runoff volume, TSS, TP and NO3− loads into Lake Pampulha and promote greater cyanobacteria biomass, mainly in the beginning of the wet season, because of additional nutrient input from catchment runoff. Recovering Lake Pampulha water quality will require the improvement of the sanitation system. The lake water quality improvement will also require more sustainable and nature-based solutions for urban drainage in order to reduce non-point pollution through infiltration and retention of stormwater and to enhance natural processes, such as chemical sorption, biodegradation and phytoremediation. The integrated modelling approach here proposed can be applied for other urban reservoirs taking advantage of existing knowledge on Lake Pampulha.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Peng Han ◽  
Jinkuan Wang ◽  
Yan Li ◽  
Yinghua Han

The large adoption of electric vehicles (EVs), hybrid renewable energy systems (HRESs), and the increasing of the loads shall bring significant challenges to the microgrid. The methodology to model microgrid with high EVs and HRESs penetrations is the key to EVs adoption assessment and optimized HRESs deployment. However, considering the complex interactions of the microgrid containing massive EVs and HRESs, any previous single modelling approaches are insufficient. Therefore in this paper, the methodology named Hierarchical Agent-based Integrated Modelling Approach (HAIMA) is proposed. With the effective integration of the agent-based modelling with other advanced modelling approaches, the proposed approach theoretically contributes to a new microgrid model hierarchically constituted by microgrid management layer, component layer, and event layer. Then the HAIMA further links the key parameters and interconnects them to achieve the interactions of the whole model. Furthermore, HAIMA practically contributes to a comprehensive microgrid operation system, through which the assessment of the proposed model and the impact of the EVs adoption are achieved. Simulations show that the proposed HAIMA methodology will be beneficial for the microgrid study and EV’s operation assessment and shall be further utilized for the energy management, electricity consumption prediction, the EV scheduling control, and HRES deployment optimization.


2006 ◽  
Vol 54 (6-7) ◽  
pp. 405-413 ◽  
Author(s):  
T.G. Schmitt ◽  
W.C. Huber

Integrated modelling has become an urgent issue of urban drainage and wastewater treatment planning. The scope of integrated modelling, system boundaries and disciplines to be involved are addressed in view of future developments and new paradigms in urban drainage, demanding the inclusion of the full urban water cycle. A system analysis is demonstrated to identify relevant sub-systems and components, processes and interactions within the urban water system. The permissibility to exclude subsystems or neglect interactions is evaluated. Integrated modelling of urban water system is characterised as an ambitious task in regard to system complexity, heterogeneous scales and interface problems. The methodical status quo is characterised in preliminary approaches towards integrated modelling. It is concluded that it does not seem promising to create and apply one entity model for the scope of integrated urban water modelling. Instead, the development of adequate and efficient IT frameworks is identified as the key issue of integrated modelling. Harmonising interfaces to facilitate the linking of existing models is presented as the objective of a European research project HarmonIT and the U.S. EPA Multimedia Integrated Modelling System project MIMS.


2011 ◽  
Vol 14 (1) ◽  
pp. 30-47 ◽  
Author(s):  
Angela Candela ◽  
Gabriele Freni ◽  
Giorgio Mannina ◽  
Gaspare Viviani

This study presents a basin-scale approach to the analysis of receiving water body quality considering both point and non-point pollution sources. In particular, this paper describes an extensive data gathering campaign carried out in the Nocella catchment, which is an agricultural and semi-urbanised basin located in Sicily, Italy. Two sewer systems, two wastewater treatment plants and a river reach were monitored during both dry and wet weather periods. A mathematical model of the entire integrated system was also created. Specifically, a detailed modelling approach was developed by employing three well known models: Storm Water Management Model, GPS-X and Soil and Water Assessment Tool. The study proposed a comprehensive modelling approach to analyse the importance of diffuse and concentrated polluting sources on receiving water quality. The study demonstrated that point pollution loads can be more influential during wet periods by an order of magnitude compared with the dry weather period. In the long term, diffuse and point pollution sources were demonstrated to affect river quality and they have both to be considered. The use of the proposed integrated model-based approach may support water managers in decision making about which strategies should be preferred with the aim of water quality preservation.


Hydrobiologia ◽  
2007 ◽  
Vol 588 (1) ◽  
pp. 13-29 ◽  
Author(s):  
S. Even ◽  
B. Thouvenin ◽  
N. Bacq ◽  
G. Billen ◽  
J. Garnier ◽  
...  

2014 ◽  
Vol 70 (11) ◽  
pp. 1838-1846 ◽  
Author(s):  
M. Mair ◽  
C. Mikovits ◽  
M. Sengthaler ◽  
M. Schöpf ◽  
H. Kinzel ◽  
...  

Research in urban water management has experienced a transition from traditional model applications to modelling water cycles as an integrated part of urban areas. This includes the interlinking of models of many research areas (e.g. urban development, socio-economy, urban water management). The integration and simulation is realized in newly developed frameworks (e.g. DynaMind and OpenMI) and often assumes a high knowledge in programming. This work presents a Web based urban water management modelling platform which simplifies the setup and usage of complex integrated models. The platform is demonstrated with a small application example on a case study within the Alpine region. The used model is a DynaMind model benchmarking the impact of newly connected catchments on the flooding behaviour of an existing combined sewer system. As a result the workflow of the user within a Web browser is demonstrated and benchmark results are shown. The presented platform hides implementation specific aspects behind Web services based technologies such that the user can focus on his main aim, which is urban water management modelling and benchmarking. Moreover, this platform offers a centralized data management, automatic software updates and access to high performance computers accessible with desktop computers and mobile devices.


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