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Östermalm, Sweden

There is a need to revise existing design methods for stormwater pollutant treatment, flow transport and detention facilities. The aim is to increase the accuracy in predicting the performance compared with design only based upon areal and volumetric functions and to optimize design by considering more site-specific data, receiving water quality criteria and forecasted climate effects. During the latest years, flow proportional concentration data from in- and outlets from wet ponds and constructed wetlands, have been compiled. Furthermore, other kind of data from the specific facilities have been compiled, such as areas, volumes, proportion of vegetation, outlet design details and length:width ratio. The parameters are used to revise design methods and are implemented in the operative stormwater and recipient software model StormTac. Design criteria and parameters for calculating design flow and sizing required detention volume are also presented. The climate effects on some of the studied parameters, e.g. design flow and inlet concentration, are discussed. The paper presents the climate factor based upon the hypothesis that it is a function of the design rain duration and reoccurrence time. © IWA Publishing 2014. Source


The large-scale geological structure of the crystalline rock at the proposed high-level nuclear waste repository site at Forsmark, Sweden, has been classified in terms of deformation zones of elevated fracture frequency. The rock between deformation zones was divided into fracture domains according to fracture frequency. A methodology to constrain the geometric and hydraulic parameters that define a discrete fracture network (DFN) model for each fracture domain is presented. The methodology is based on flow logging and down-hole imaging in cored boreholes in combination with DFN realizations, fracture connectivity analysis and pumping test simulations. The simulations suggest that a good match could be obtained for a power law size distribution where the value of the location parameter equals the borehole radius but with different values for the shape parameter, depending on fracture domain and fracture set. Fractures around 10-100 m in size are the ones that typically form the connected network, giving inflows in the simulations. The report also addresses the issue of up-scaling of DFN properties to equivalent continuous porous medium (ECPM) bulk flow properties. Comparisons with double-packer injection tests provide confidence that the derived DFN formulation of detailed flows within individual fractures is also suited to simulating mean bulk flow properties and their spatial variability. © 2013 Springer-Verlag Berlin Heidelberg. Source


Edwards Y.,Swedish Cement and Concrete Research Institute | Emilsson T.,Swedish University of Agricultural Sciences | Malmberg J.,The Roof | Skog A.P.,SWECO Environment
WIT Transactions on Ecology and the Environment | Year: 2014

Eco neighborhoods with green infrastructure solutions are increasingly being prescribed today in Swedish cities for reducing and attenuating storm water runoff, increasing biodiversity, having a temperature moderating effect and for energy saving. Thus, contractors are simply required to build with green gardens on concrete decks, such as green roofs, green terraces, green courtyards and green complete neighborhoods. A lot of knowledge and experience is in fact lacking today, and consequences may therefore be devastating. If green system solutions are to be seen as an obvious choice in future settlements, and not as a problem, there must be clear guidelines and specifications that ensure a sustainable outcome. This is missing today. This paper reports a project aiming at bringing together researchers, government and industry to the collaborative development of new and attractive solutions for green roof gardens with consideration to the environment and high requirements for durability, materials, construction and energy efficiency. These solutions must also be adaptable to similar types of facilities, specific needs and environments. One such area concerns public land such as parks, streets and squares on concrete decks. Certification and tailored guidelines for different types of systems are being developed. The initiating part of this project clearly indicates that there is a need for better understanding, more research and long term monitoring/follow up of green roofs. Furthermore, a holistic approach is introduced to ensure that one good green roof function will not have severe negative effects on other functions. © 2014 WIT Press. Source


Ulusoy I.,Hacettepe University | Ulusoy I.,Lund University | Dahlin T.,Lund University | Bergman B.,SWECO Environment
Hydrogeology Journal | Year: 2015

Managed aquifer recharge (MAR) is an efficient way to remove organic matter from raw water and, at the same time, reduce temperature variation. Two MAR sites were constructed by Karlskrona municipality on Johannishus Esker in Sweden. One of these sites, Vång, was monitored for electrical conductivity and electrical resistivity (using electrical resistivity tomography - ERT) during a 9-week tracer infiltration test. The aim of the monitoring was to map the pathways of the infiltrated water, with the overall goal to increase the efficiency of the MAR. ERT proved useful in determining both the nature of the esker formation and the water migration pathways. In Vång, the esker ridge follows a tectonically controlled paleo-valley. The fault/fracture zone in the bedrock along this paleo-valley was mapped. During the tracer test, the infiltrated water was detected in the area close to the infiltration ponds, whereas far-situated observation wells were less affected. For sequential infiltration and recharge periods in MAR, the timing of the well pumping is another important factor. Natural groundwater flow direction was a determinant in the infiltration process, as expected. ERT measurements provide supplementary data for site selection, for monitoring the functionality of the MAR sites, and for revealing the geological, hydrogeological and structural characteristics of the site. © 2014, Springer-Verlag Berlin Heidelberg. Source


Ulusoy E.,Hacettepe University | Ulusoy E.,Lund University | Dahlin T.,Lund University | Bergman B.,SWECO Environment
Hydrogeology Journal | Year: 2015

Managed aquifer recharge (MAR) is an efficient way to remove organic matter from raw water and, at the same time, reduce temperature variation. Two MAR sites were constructed by Karlskrona municipality on Johannishus Esker in Sweden. One of these sites, Vång, was monitored for electrical conductivity and electrical resistivity (using electrical resistivity tomography - ERT) during a 9-week tracer infiltration test. The aim of the monitoring was to map the pathways of the infiltrated water, with the overall goal to increase the efficiency of the MAR. ERT proved useful in determining both the nature of the esker formation and the water migration pathways. In Vång, the esker ridge follows a tectonically controlled paleo-valley. The fault/fracture zone in the bedrock along this paleo-valley was mapped. During the tracer test, the infiltrated water was detected in the area close to the infiltration ponds, whereas far-situated observation wells were less affected. For sequential infiltration and recharge periods in MAR, the timing of the well pumping is another important factor. Natural groundwater flow direction was a determinant in the infiltration process, as expected. ERT measurements provide supplementary data for site selection, for monitoring the functionality of the MAR sites, and for revealing the geological, hydrogeological and structural characteristics of the site. © 2014, Springer-Verlag Berlin Heidelberg. Source

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