Sustainability criteria for the selection of water supply pipeline

The evolution of the materials used for drinking water pipelines has often introduced substantial innovations in the market, both in terms of improved static and hydraulic performance and cost. Over time, technical and cost-effective assessments to pipelines selection, related to the materials used, have been accompanied by environmental assessments in relation to the environmental impact of construction and management of drinking water system. The recent legislative and technical regulations have made the environmental cost assessment more complex, which is related to the life cycle of materials and infrastructures. This paper proposes an index, In Situ Sustainability Index (ISSI), which can be used for the pipelines materials choice for drinking water systems and which takes into account both technical and environmental aspects. This index considers the interaction between piping and laying soil, through the In Situ Elasticity Coefficient and the impacts of materials used for water system piping through Life Cycle Assessment. The ISSI index is a practical tool because it makes a simultaneous consideration of two essential aspects in the design (technical and environmental evaluations) through a rapid-use analytical structure

Trends in metering potable water

Abstract Sustainable management of drinking water distribution systems requires information on the operating status of system components to identify the best operational management measures. The ability to acquire information on tank levels, pipeline flow and real-time pressure offers an efficient and cost-effective management perspective, and enables wider monitoring, which can improve (physical) security as well. The technology of measuring instruments for hydrodynamic variables, used to monitor potable water systems, differs in their independence from electronic data acquisition components and ability to connect to remote data communication systems. Advanced water measurement infrastructure is characterized by the ability to capture data with measurable errors from anywhere in the system, without restrictions on communication type. This paper deals with the measurement of hydrodynamic parameters and a proposal for water meter classification. It includes analysis of the main water meter and data tele-acquisition infrastructure. Several selection criteria are evaluated with respect to their ability to support mathematical hydraulic models and expert systems for water distribution system management

Findings from an in-depth annual tree-ring radiocarbon inter-comparison

The radiocarbon calibration curve so far contains annually resolved data only for a short period of time. With accelerator mass spectrometry (AMS) matching the precision of decay counting, it is now possible to efficiently produce large datasets of annual resolution for calibration purposes using small amounts of wood. The radiocarbon inter-comparison on single-year tree-ring samples presented here is the first to investigate specifically possible offsets between AMS laboratories at high precision. The results show that AMS laboratories are capable of measuring samples of Holocene age with an accuracy and precision that is comparable or even goes beyond what is possible with decay counting, even though they require a thousand times less wood. It also shows that not all AMS laboratories always produce results that are consistent with their stated uncertainties. The long-term benefits of studies of this kind are more accurate radiocarbon measurements with, in the future, better quantified uncertainties.Additional co-authors: Douglas J Kennett, Timothy D J Knowles, Margot Kuitems, Todd E Lange, Fusa Miyake, Marie-Josée Nadeau, Toshio Nakamura, J Philip Naysmith, Jesper Olsen, Takayuki Omori, Fiona Petchey, Bente Philippsen, Christopher Bronk Ramsey, G V Ravi Prasad, Martin Seiler, John Southon, Richard Staff, Thibault Tun

Development of small CO2 gas measurements with AixMICADAS

International audienceAfter three years of tests and developments, the performances of the AixMICADAS facility have been established for small CO 2 samples with a carbon mass inferior to 100 μg. The instrument shows very good stability and reliability when measuring small samples with its gas ion source. In this configuration, the precision is mainly limited by counting statistics and also the accuracy by contamination effects for the smallest samples (< 20 μgC). A long term variability of 7-8‰ is evaluated with 80-100 μgC NIST oxalic acid 2 samples and modern carbonate samples. Our pretreatment and analytical protocols allow for very low blank levels corresponding to 14 C ages of 53,000 years BP and 48,000 years BP for carbonate samples and organic materials, respectively