Time filter
Source Type

Tamari S.,IMTA | Garcia F.,ENGEES | Arciniega-Ambrocio J.I.,ITCh | Porter A.,MECOPAA
Houille Blanche | Year: 2014

Among the non-contact instruments to measure water velocity in open channels, two handheld radars are available on the market since ten years. Due to the lack of information about these instruments, one model was tested in the laboratory and in the field. The radar was able to estimate the velocity of a water surface within [p = 0.95] ± 0.3 m/s at medium velocities (from 0.3 to 3 m/s) and within ± 10 % of the measured value at large velocities (up to at least 6 m/s). Although this is not very accurate, the ease of using handheld radars still makes them attractive to quickly estimate discharge at gauging stations, safely determine water velocity during a flood and investigate how water flows under difficult access conditions. Nevertheless, the tested radar was tending to underestimate the water velocity, above all when it was looking downstream. More studies are necessary to know why. © 2014 Société Hydrotechnique de France .

Bernard T.,Fraunhofer Institute for Optronics, System Technologies and Image Exploitation | Braun M.,Fraunhofer Institute for Optronics, System Technologies and Image Exploitation | Piller O.,IRSTEA | Gilbert D.,IRSTEA | And 8 more authors.
ISCRAM 2013 Conference Proceedings - 10th International Conference on Information Systems for Crisis Response and Management | Year: 2013

Water distribution Networks (WDNs) are critical infrastructures that are exposed to deliberate or accidental contamination. Until now, no monitoring system is capable of protecting a WDN in real time. In the immediate future water service utilities that are installing water quantity and quality sensors in their networks will be producing a continuous and huge data stream for treating. The main objective of the project SMaRT-OnlineWDN is the development of an online security management toolkit for water distribution networks that is based on sensor measurements of water quality as well as water quantity and online simulation. Its field of application ranges from detection of deliberate contamination, including source identification and decision support for effective countermeasures, to improved operation and control of a WDN under normal and abnormal conditions.

Leviandier T.,ENGEES | Madier S.,ENGEES | Payraudeau S.,CNRS Hydrology and Geochemistry Laboratory of Strasbourg
Stochastic Environmental Research and Risk Assessment | Year: 2012

Sampling strategies are necessary to minimise the cost of data acquisition. We consider the case when several samples must be analysed at the same time, knowing rainfall data, optionally discharge data. We assume also that a rainfall-runoff and pesticide transfer model is available. Three methods are presented based on behavioural sets calculated on prior events, which provide optimal sampling times with respect to different statistical criteria, for a fixed number of samples. A methodology to compare these strategies, adapted to a context of data scarcity is proposed for proper validation. We consider that the combination of a model and a strategy is efficient if it does better than a strategy without a model based on equal volumes. Even with a simple and relatively poor model, it can be concluded that the different strategies are efficient and show similar efficiency in spite of their different levels of conceptual and algorithmic complexity. © 2011 Springer-Verlag.

Rulleau B.,University of Versailles | Rulleau B.,IRSTEA | Dumax N.,Upper Alsace University | Rozan A.,ENGEES
Journal of Environmental Planning and Management | Year: 2016

A choice experiment was used to analyse the preferences of residents neighbouring the Erstein polder (Alsace, France) for the different services that it provides. The heterogeneous nature of these preferences was shown through the use of a latent class model. Whilst the population as a whole values the improvement in water quality and the contribution, even partial, to flood protection, preferences differ when it comes to biodiversity and public access to the site. This study shows the potential conflicts between the different uses of the Erstein polder. These conflicts represent different communication themes for the site managers. © 2016 University of Newcastle upon Tyne

Duguay J.,Université de Sherbrooke | Lacey R.W.J.,Université de Sherbrooke | Jaillet E.,École Centrale Lyon | Floriani F.,ENGEES
Proceedings of the International Conference on Fluvial Hydraulics, RIVER FLOW 2014 | Year: 2014

Fish baffle installation in HDPE slip lined road culverts is a popular method to reduce flows and promote fish passage. Though beneficial for fish, the insertion of baffles in culverts is known to reduce the hydraulic capacity of slip lined culverts causing increased water levels upstream and potentially the overtopping of the road. Previous studies have suggested that fish maneuver more easily through spoiler baffles than other more traditional baffle types (e.g., weir, slotted weir). Little is known concerning the extents to which spoiler baffles affect discharge capacity. To respond to this need, specific configurations of spoiler baffles were investigated in detail to determine how spacing/size (and inline vs staggered) configurations affect energy losses. Fine-scale spatial and temporal characterisation of the flow field around both inline and staggered baffles configurations was also performed using an acoustic Doppler velocimeter. Results reveal that hydraulic roughness decreases near linearly with increasing baffle spacing for all baffle configurations, reflective of isolated roughness flow. Baffle height was determined to be the dominant geometric parameter affecting roughness. The fine scale flow structure results indicate much similarity between inline and staggered baffles. Both configurations of baffles offer low refuges near the channel invert, yet the near wake of the baffles is characterized by high turbulence. © 2014 Taylor & Francis Group, London.

Many developing countries are committed to a decentralization process of their irrigation system. Farmers have to self-govern their productive activities. Such developments raise the usual challenges of cooperation in collective action providing collective goods. The aim of this investigation is to examine farmers' cooperative behavior. For this purpose, we set up a public good experiment. Public good games are relevant to investigate cooperative behavior. Game theory predicts a free riding strategy as a best reply to the strategic issue of the game. The player maximizes his welfare by benefiting from the effort provided by other members of his group. Experimentation shows that subjects are more cooperative than the theoretical prediction. However, they learn to free ride during the experiment. Several critics are addressed to such experiments, especially concerning the issue of external validity of the results. The aim of this investigation is to conduct an experiment with farmers in order toexamine their cooperative behavior. The experiment shows that farmers reach a higherlevel of cooperation that is sustained over time.

Schlierf K.,ENGEES | Aissani L.,IRSTEA | Mery J.,IRSTEA
Waste and Biomass Valorization | Year: 2013

The use of LCA in waste management is an emerging field in France and other European countries. This paper provides feedback on the methodological challenge of incorporating LCA results in decision making processes. LCA is expected to answer the demand for global and exhaustive environmental evaluation of waste management scenarios particularly well, whereas its methodological suitability for this particular field is still under discussion. One unanswered question is how to ensure "satisfactory" incorporation of LCA results in the decision making process, i.e. between multi-criteria analysis and simplification. This paper provides evidence from a case study in which non-aggregated LCA results were fed into the decision making process at an early stage in the planning process with the involvement of the stakeholders. Interviews with different stakeholders as well as in-depth analysis of documentation on the decision making process concerned, and of the LCA, allow us to discuss how the multi-criteria character of LCA and its results fit the process despite diverging points of view. The results of the case study were interpreted in an interdisciplinary dialogue between researchers in LCA methodology and social scientists. In terms of research findings, we report that appropriation and comprehension of the non-aggregated LCA results were rather high, also by the stakeholders involved. In our case, the successful incorporation of nonaggregated multi-criteria results was not so much a problem of comprehensibility as might be expected. Instead, our case study sheds light on the complex political roles LCA can play in waste management. © Springer Science+Business Media Dordrecht 2012.

Barreteau O.,IRSTEA | Sauquet E.,IRSTEA | Riaux J.,IRD | Gailliard N.,IRSTEA | Barbier R.,ENGEES
Advances in Intelligent Systems and Computing | Year: 2014

Drought management in France is implemented locally. Due to discrepancies between assessment of drought situation by managing agency on one hand and water users on the other hand, as well as to uncertainty in measures and benchmarks, its efficiency is limited. We propose in this paper an agent based model designed to represent the suitable indicators of drought at the suitable spatial scale for any category of stakeholders. Initial test of the model show its suitability to explore sensitivity of efficiency of drought management setting according to its context: population of water users and their attitudes to water restriction rules as well as practical details of implementation. © Springer-Verlag Berlin Heidelberg 2014.

Loading ENGEES collaborators
Loading ENGEES collaborators