Long-term hydraulic and pollution retention performance of infiltration systems

Infiltration techniques are now widely used to manage stormwater in urban areas. These techniques are used and recognized around the world for their many advantages, such as decreasing stormwater flow in sewer systems and recharging groundwater. But numerous cases of infiltration devices that failed after a few years of operation are still being reported. This study, which is based on site-monitoring of operational infiltration systems, is part of the Field Observatory for Urban Water Management (OTHU). The main goals of this study are to improve knowledge of long-term hydraulic behaviour, especially as concerns the clogging speed and the quality of the runoff. This article will present the site, the monitoring process and the model that will be used to assess the hydraulic behaviour. First results of the calibration of the model show that the model is able to assess the hydraulic behaviour of the basin when it is clogged (average value of hydraulic resistance 17.1 h) and when it has been scraped (hydraulic resistance less than 3.8 h). However, further data are needed in order to validate the model. We also show that the experimental setup is well designed to assess the water volume and the sediment brought to the basin with low uncertainties.

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Seepage metal concentrations beneath long-term operated bioretention systems

Blue-Green Systems ◽

10.2166/bgs.2021.014 ◽

2021 ◽

Author(s):

Arne Reck ◽

Mogens Thalmann ◽

Eva Paton ◽

Björn Kluge

Keyword(s):

Trace Metal ◽

Urban Areas ◽

Field Experiments ◽

Water Cycle ◽

Retention Rates ◽

Trace Metal Concentration ◽

Retention Performance ◽

Metal Retention ◽

Metal Contents

Abstract Bioretention systems maintain the natural water cycle and help to mitigate climatic extremes impact on urban areas by retarding, storing, and evaporating stormwater runoff. Although bioretention systems have been operated for more than 25 years, systematic investigations on the hydrological functionality and pollutant retention performance of older systems are rare. We employed laboratory and field experiments to investigate three long-term operated bioretention systems in Germany with the following objectives: (i) physico-chemical substrate characterisation; (ii) an event-based influent and effluent trace metal concentration monitoring covering 22 months and (iii) the calculation of metal retention rates. Regarding the pollution status, we found significantly increased trace metal contents in the soil substrate mainly as a function of the drainage area type and the inflow regime. Nonetheless, all measured metal seepage concentrations fall below the German legislative trigger values. Our current findings demonstrate no risk of groundwater degradation even for old bioretention systems suggesting bioretention as a powerful and sustainable tool for stormwater management. Further research requires the handling of soil substrates modified by stormwater infiltration showing enhanced trace metal contents and a certain amount of technogenic sediments.

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On-site monitoring in a passive house

International Review of Applied Sciences and Engineering ◽

10.1556/irase.2.2011.1.6 ◽

2011 ◽

Vol 2 (1) ◽

pp. 39-44

Author(s):

T. Csoknyai ◽

A. Talamon

Keyword(s):

Heat Exchangers ◽

First Year ◽

Passive House ◽

Site Monitoring ◽

First Results ◽

Long Term Monitoring ◽

In The Beginning ◽

Building Occupancy ◽

Term Monitoring

Abstract In the beginning of August 2009 a long-term monitoring started in a recently built passive house near Isaszeg. The first results were presented in the last year's conference. The present paper gives an overview about a whole-year data evaluation focusing on energy consumption. During the first year of building occupancy three types of heat suppliers and two types of heat exchangers in the ventilation systems were applied and monitored, thus different heating options could be compared.

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Implementation of a monitoring system to measure impact of stormwater runoff infiltration

Water Science & Technology ◽

10.2166/wst.2002.0080 ◽

2002 ◽

Vol 45 (3) ◽

pp. 203-210 ◽

Cited By ~ 38

Author(s):

S. Barraud ◽

J. Gibert ◽

T. Winiarski ◽

J.-L. Bertrand Krajewski

Keyword(s):

Urban Areas ◽

Field Experiments ◽

Experimental Site ◽

Monitoring Process ◽

The Will ◽

Stormwater Infiltration ◽

The Impact ◽

Term Monitoring

Stormwater infiltration is a drainage mode, which is more and more used in urban areas in France. Given the characteristics of urban surfaces, and especially the loads of various pollutants contained in stormwater, it is important to assess the impact of stormwater infiltration systems on soil and groundwater by carrying out field experiments. The main difficulty is due to the complexity of the system observed and the need of multidisciplinary approaches. Another difficulty is that measurements are carried out in situ, in an uncontrolled environment submitted to quantitatively and qualitatively highly variable interferences. Very long term monitoring is needed to get representative results. In order to contribute to solve these problems, the OTHU project has recently been launched in Lyon (France). One of its key action concerns a long-term (10 years) experiment on an infiltration basin specifically rehabilitated for measurements and operational drainage issues. This paper presents the experimental site, the objectives of the project and the way the monitoring process has been built according to the various disciplines involved (biology, ecology, hydrology, chemistry and soil sciences) and to the will of assessing all the uncertainties in the measurement process.

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Stents for the Treatment of Aortic Aneurysms

Thrombosis and Haemostasis ◽

10.1055/s-0037-1615578 ◽

1999 ◽

Vol 82 (S 01) ◽

pp. 171-175 ◽

Cited By ~ 1

Author(s):

D. Ebert ◽

M. Langer ◽

P. Uhrmeister

Keyword(s):

Endovascular Treatment ◽

Endovascular Repair ◽

Abdominal Aortic Aneurysms ◽

Aortic Aneurysms ◽

Imaging Modalities ◽

Exclusion Criteria ◽

Multicenter Studies ◽

Abdominal Aortic ◽

First Results

SummaryThe endovascular treatment of abdominal aortic aneurysms has generated a great deal of interest since the early 1990s, and many different devices are currently available. The procedure of endovascular repair has been evaluated in many institutions and the different devices are compared. The first results were encouraging, but complications like endoleak, dislocation or thrombosis of the graft occurred. By the available devices the stent application is only promising, if the known exclusion criteria are strictly respected. Therefore a careful preinterventional assessment of the patient by different imaging modalities is necessary. As the available results up to now are preliminary and the durability of the devices has to be controlled, multicenter studies are required to improve the devices and observe their long- term success in the exclusion of abdominal aortic aneurysms.

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Spatiotemporal Changes of Riverbed and Surrounding Environment in Yongding River (Beijing section) in the Past 40 Years

Journal of Imaging Science and Technology ◽

10.2352/j.imagingsci.technol.2020.64.4.040407 ◽

2020 ◽

Vol 64 (4) ◽

pp. 40407-1-40407-13 ◽

Cited By ~ 1

Author(s):

Ran Pang ◽

He Huang ◽

Tri Dev Acharya

Keyword(s):

Economic Development ◽

Water Conservation ◽

Human Activities ◽

Urban Areas ◽

Water Volume ◽

Cropland Area ◽

The Past ◽

Surrounding Environment ◽

Spatiotemporal Changes ◽

Yongding River

Abstract Yongding River is one of the five major river systems in Beijing. It is located to the west of Beijing. It has influenced culture along its basin. The river supports both rural and urban areas. Furthermore, it influences economic development, water conservation, and the natural environment. However, during the past few decades, due to the combined effect of increasing population and economic activities, a series of changes have led to problems such as the reduction in water volume and the exposure of the riverbed. In this study, remote sensing images were used to derive land cover maps and compare spatiotemporal changes during the past 40 years. As a result, the following data were found: forest changed least; cropland area increased to a large extent; bareland area was reduced by a maximum of 63%; surface water area in the study area was lower from 1989 to 1999 because of the excessive use of water in human activities, but it increased by 92% from 2010 to 2018 as awareness about protecting the environment arose; there was a small increase in the built-up area, but this was more planned. These results reveal that water conservancy construction, agroforestry activities, and increasing urbanization have a great impact on the surrounding environment of the Yongding River (Beijing section). This study discusses in detail how the current situation can be attributed to of human activities, policies, economic development, and ecological conservation Furthermore, it suggests improvement by strengthening the governance of the riverbed and the riverside. These results and discussion can be a reference and provide decision support for the management of southwest Beijing or similar river basins in peri-urban areas.

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EBS Behaviour Immediately After Repository Closure in a Clay Host Rock: The HE-E Experiment (Mont Terri URL)

ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management, Parts A and B ◽

10.1115/icem2011-59288 ◽

2011 ◽

Cited By ~ 1

Author(s):

Irina Gaus ◽

Klaus Wieczorek ◽

Juan Carlos Mayor ◽

Thomas Trick ◽

Jose´-Luis Garcia` Sin˜eriz ◽

...

Keyword(s):

Thermal Conductivity ◽

Host Rock ◽

Large Scale ◽

Process Models ◽

Research Activities ◽

Hydraulic Behaviour ◽

Validation Experiment ◽

Engineered Barrier ◽

Mont Terri

The evolution of the engineered barrier system (EBS) of geological repositories for radioactive waste has been the subject of many research programmes during the last decade. The emphasis of the research activities was on the elaboration of a detailed understanding of the complex thermo-hydro-mechanical-chemical processes, which are expected to evolve in the early post closure period in the near field. It is important to understand the coupled THM-C processes and their evolution occurring in the EBS during the early post-closure phase so it can be confirmed that the safety functions will be fulfilled. Especially, it needs to be ensured that interactions during the resaturation phase (heat pulse, gas generation, non-uniform water uptake from the host rock) do not affect the performance of the EBS in terms of its safety-relevant parameters (e.g. swelling pressure, hydraulic conductivity, diffusivity). The 7th Framework PEBS project (Long Term Performance of Engineered Barrier Systems) aims at providing in depth process understanding for constraining the conceptual and parametric uncertainties in the context of long-term safety assessment. As part of the PEBS project a series of laboratory and URL experiments are envisaged to describe the EBS behaviour after repository closure when resaturation is taking place. In this paper the very early post-closure period is targeted when the EBS is subjected to high temperatures and unsaturated conditions with a low but increasing moisture content. So far the detailed thermo-hydraulic behaviour of a bentonite EBS in a clay host rock has not been evaluated at a large scale in response to temperatures of up to 140°C at the canister surface, produced by HLW (and spent fuel), as anticipated in some of the designs considered. Furthermore, earlier THM experiments have shown that upscaling of thermal conductivity and its dependency on water content and/or humidity from the laboratory scale to a field scale needs further attention. This early post-closure thermal behaviour will be elucidated by the HE-E experiment, a 1:2 scale heating experiment setup at the Mont Terri rock laboratory, that started in June 2011. It will characterise in detail the thermal conductivity at a large scale in both pure bentonite as well as a bentonite-sand mixture, and in the Opalinus Clay host rock. The HE-E experiment is especially designed as a model validation experiment at the large scale and a modelling programme was launched in parallel to the different experimental steps. Scoping calculations were run to help the experimental design and prediction exercises taking the final design into account are foreseen. Calibration and prediction/validation will follow making use of the obtained THM dataset. This benchmarking of THM process models and codes should enhance confidence in the predictive capability of the recently developed numerical tools. It is the ultimate aim to be able to extrapolate the key parameters that might influence the fulfilment of the safety functions defined for the long term steady state.

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A Study of UVER in Santiago, Chile Based on Long-Term In Situ Measurements (Five Years) and Empirical Modelling

Energies ◽

10.3390/en14020368 ◽

2021 ◽

Vol 14 (2) ◽

pp. 368

Author(s):

Lisdelys González-Rodríguez ◽

Amauri Pereira de Oliveira ◽

Lien Rodríguez-López ◽

Jorge Rosas ◽

David Contreras ◽

...

Keyword(s):

Urban Areas ◽

Solar Spectrum ◽

Sun Exposure ◽

Great Accuracy ◽

In Situ Measurements ◽

Uv Index ◽

Empirical Modelling ◽

The People

Ultraviolet radiation is a highly energetic component of the solar spectrum that needs to be monitored because is harmful to life on Earth, especially in areas where the ozone layer has been depleted, like Chile. This work is the first to address the long-term (five-year) behaviour of ultraviolet erythemal radiation (UVER) in Santiago, Chile (33.5° S, 70.7° W, 500 m) using in situ measurements and empirical modelling. Observations indicate that to alert the people on the risks of UVER overexposure, it is necessary to use, in addition to the currently available UV index (UVI), three more erythema indices: standard erythemal doses (SEDs), minimum erythemal doses (MEDs), and sun exposure time (tery). The combination of UVI, SEDs, MEDs, and tery shows that in Santiago, individuals with skin types III and IV are exposed to harmfully high UVER doses for 46% of the time that UVI indicates is safe. Empirical models predicted hourly and daily values UVER in Santiago with great accuracy and can be applied to other Chilean urban areas with similar climate. This research inspires future advances in reconstructing large datasets to analyse the UVER in Central Chile, its trends, and its changes.

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Evaluation attempt of own body sensing amongst persons with and without scoliosis

Journal of Back and Musculoskeletal Rehabilitation ◽

10.3233/bmr-191761 ◽

2021 ◽

pp. 1-6

Author(s):

Elżbieta Szczygieł ◽

Agata Gigoń ◽

Izabela Cebula Chudyba ◽

Golec Joanna ◽

Golec Edward

Keyword(s):

Idiopathic Scoliosis ◽

Sensory Integration ◽

Head Position ◽

Clinical Test ◽

Spine Deformity ◽

Functional Tests ◽

Body Proportion ◽

Average Value ◽

Age Range

BACKGROUND: Adolescent idiopathic scoliosis (AIS) is a common structural spine deformity affecting 2%–4% of adolescents. Due to the unknown cause of idiopathic scoliosis, its therapy is a long-term and often unsatisfactory process. In the literature, it is often suggested that problems related to the feeling of one’s own body are caused by AIS. OBJECTIVE: The aim of this study was to assess the feeling of one’s own body among children with and without scoliosis on the example of feeling the head position, pelvis shape and balance. METHOD: The research included 62 children: 30 with scoliosis and 25 without diagnosed scoliosis with an age range between 11 to 19 years. The minimum scoliosis value was 7∘ and the maximum was 53∘. The average value was 25∘. During the study, three functional tests were used: Cervical Joint Position Error Test (CJPET), Clinical Test of Sensory Integration on Balance (CTSIB) and Body proportion demonstration test (BPDT). RESULTS: The results of the tests showed statistically significant differences (CJPET p= 3.54* 10-14, CTSIB p= 0.0376, BPDT p= 0.0127). However, none of the studies showed a correlation between the results of people with scoliosis and the value of their Cobb angles.

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