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  • 101.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    National Water Research Institute, Environment Canada.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Laboratory study of stormwater biofiltration in low temperatures: total and dissolved metal removal and fates2011Inngår i: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 219, nr 1-4, s. 303-317Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stormwater biofilters, which are recommended for application in both Water-Sensitive Urban Design and Low Impact Development, can remove up to 80% or 90% of total metals found in stormwater. However, their winter operation is a common concern. That was addressed in this study by investigating the metal removal effectiveness of replicate laboratory biofilter mesocosms at 2°C, 8°C and 20°C. As recommended for cold climate bioretention, coarse filter media were implemented and in the top 100 mm layer topsoil was added to increase the sorption capacity. Cd, Cu, Pb and Zn concentrations measured in the biofilter effluent were far below those in the influent and this significantly improved the treated stormwater quality. Contrary to a common notion that coarse media in the main filter body impair dissolved metal sorption, satisfactory removals of dissolved metals were found in this study with most metal burdens retained in the top layer of the filter in which the sorption capacity was enhanced by topsoil. Some metal uptake by the plants was also detected. Temperature did not affect Cd, Pb and Zn removals in general, but Cu removals increased with decreasing temperatures. This was explained by increased biological activities in the filters at warmer temperatures, which may have led to an increased release of Cu with dissolved organic matter originating from root turnover and decomposition of organic litter and debris. Furthermore, plant uptake and biofilm adsorption may also be influenced by temperature. However, even in the worst case (i.e. at 20°C), Cu was removed effectively from the stormwater. Further research needs were identified including the effects of road salts on stormwater biofiltration during the winter period.

  • 102.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Rentz, Ralf
    Malmgren, Charlotte
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Stormwater impact on urban waterways in a cold climate: variations in sediment metal concentrations due to untreated snowmelt discharge2012Inngår i: Journal of Soils and Sediments, ISSN 1439-0108, E-ISSN 1614-7480, Vol. 12, nr 5, s. 758-773Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Purpose: Stormwater discharges include contaminated sediments that accumulate in the receiving water body. It is thus important to investigate sediment and pollutant processes and pathways from the catchment to, and within, the receiving water. These processes may be influenced by seasonal changes. The objective of this study was to investigate the stormwater impact on receiving waters in the Luleå area, Northern Sweden; seasonal changes in contamination loads in the receiving waters due to snowmelt; and factors influencing the pollutant pathways in the receiving waters. Materials and methods: In front of three storm sewer outlets in Luleå, samples of bottom sediment (surface layer 0-2 cm) were collected from the connecting ditches and the downstream water body in autumn and spring (before and after the snow season 2009/2010). The characteristics of the receiving waters differed in geomorphology and vegetation. The sediment was analyzed for loss-on-ignition (LOI), grain size, and bulk concentrations of SiO 2, Al 2O 3, CaO, Fe 2O 3, MnO, Na 2O, P 2O 5, TiO 2, As, Cd, Co, Cr, Cu, Hg, Ni, Pb, S, V, and Zn. The sediment contamination was compared to concentrations at a reference point in Luleå where the bottom sediment was not affected by stormwater discharges and with Swedish environmental quality guidelines. Pearson's correlation and a principal component analysis were used to further evaluate the results. Results and discussion: Relative to the reference point, elevated trace metal concentrations were detected in sediments at all three sampling stations. At two of the stations, seasonal variations in ditch sediment grain size, LOI, and contaminant concentrations were observed, originating from stormwater sediment. Snowmelt runoff caused an increased proportion of fine-grained sediment fractions (<0.063 mm) in spring, mainly due to changes in runoff intensity and high sediment loads in the snowmelt runoff. The retention of metals appeared to be due to low turbulence in the water and the presence of organic material. Conclusions: Stormwater discharge affected the contaminant concentrations in the bottom sediments. The observed seasonal variation of contaminants indicated that relatively high amounts of contaminants are discharged during snowmelt and then reallocated within the receiving water body, either directly or after some temporal retention, depending on the characteristics of the receiving water. A calm water column and the presence of organic material in the receiving water body were crucial for the retention of metals

  • 103.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Tondera, Katharina
    Stormwater Research Group, University of the Sunshine Coast, Maroochydore.
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Metals: Occurrence, Treatment Efficiency and Accumulation Under Varying Flows2018Inngår i: Ecotechnologies for the Treatment of Variable Stormwater and Wastewater Flows / [ed] Katharina Tondera, Godecke-Tobias Blecken, Florent Chazarenc, Chris C. Tanner, Cham: Springer, 2018, s. 75-91Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Metals were the first priority pollutants to be widely investigated in stormwater. In solid phase, they are often attached to very fine particles. The dissolved fraction creates considerable environmental problems as it is the most bioavailable fraction. Hence, removal of both fine and dissolved particles plays a major role in the treatment of polluted runoff. Ecotechnologies specifically designed to remove metals should be able to address different treatment mechanisms. However, the exhaustion of sorption capacity reduces the lifespan of treatment facilities. Additionally, metal concentrations fluctuate extremely—spatially, seasonally and over time—which poses another challenge for further increasing removal efficiencies. While soil- or sand-based systems should be designed in a way that the filter material can be exchanged, newer developments such as Floating Treatment Wetlands show promising removal capacities as the installations bind metals in sludge sediments, which can be removed from time to time. The different treatment mechanisms, aforementioned developments and techniques as well as their removal capacities will be discussed in this chapter

  • 104. Blecken, Godecke-Tobias
    et al.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Muthanna, Tone M.
    Norwegian University of Science and Technology (NTNU), Trondheim.
    Zinger, Yaron
    Monash University, Melbourne, VIC.
    Deletic, Ana
    Monash University, Melbourne, VIC.
    Fletcher, Tim
    Monash University, Melbourne, VIC.
    Biofilter treatment of stormwater: temperature influence on the removal of nutrients2007Inngår i: Techniques et stratégies durables pour la gestion des eaux urbaines par temps de pluie: 6e Conférence internationale, [25-27] juin 2007, Lyon, France, Villeurbanne: Graie , 2007Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Nutrients can cause eutrophication of natural water bodies. Thus, urban stormwater which is an important nutrient source has to be treated in order to reduce its nutrient loads. Biofilters which use media, biofilms and plants, are a good treatment option regarding nutrients. This paper presents the results of a biofilter column study in cold temperatures (+2°C, +8°C, control at +20°C) which may cause special problems regarding the biofilter performance. It was shown that particle bound pollutants as TSS and a high fraction of phosphorus were reduced well without being negatively influenced by cold temperatures. Nitrogen, however, was not reduced; especially NOx was produced in the columns which can be explained with both insufficient denitrification and high leaching from the columns.

  • 105. Blecken, Godecke-Tobias
    et al.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Svensson, Gilbert
    Hedström, Annelie
    Fat, oil and grease (FOG) in sewer systems: a significant problem in Sweden and Norway2009Konferansepaper (Annet vitenskapelig)
  • 106.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Svensson, Gilbert
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Fett i avloppsnät: kartläggning och åtgärdsförslag2010Rapport (Annet vitenskapelig)
    Abstract [en]

    Fat oil and grease (FOG) from food preparation can cause severeproblems if it is discharged to the municipal sewer network. A surveyamong Swedish and Norwegian municipalities has shown that nearlyall respondents experience FOG-related problems. The most commonproblem is FOG accumulation connected to the sewer pipes whichdecreases the pipe pipe capacity and may lead to sewer overflows. FOGaccumulation occurs especially at lift stations and depressions. FOGdeposits are often made up of saponised FOG. The fatty acids promotefurthermore corrosion of concrete pipes. FOG can even impact wastewater treatment and might cause severer working conditions.The aim for the water suppliers has thus to be an effective FOGsource control before FOG is discharged to the sewer network. Sourcesare both commercial establishments and residential sewer customers.In this report different source control measures are discussed. Greaseinterceptors are commonly used for commercial FOG sources. However,a number of them lack a grease interceptor and quite often operationand maintenance is deficient. An insufficient frequency ofemptying and a lack of supervision have been identified as a commonproblem. FOG collection systems for commercial FOG producers existin both Sweden and Norway. Collection systems for private householdsare currently in a test phase and experiences from among others Austriaare promising. Even the collected amount of FOG could presumablybe increased. Collected FOG and FOG slurry from interceptors is avaluable resource which can be used as raw material in the chemicalindustry or as an energy source (combustion, biodiesel, fermentation).Threshold values for FOG discharges are set up commonly by municipalities.However, even here supervision is often insufficient. Often, thethreshold values are inadequately low and a value of at least 150 mg/lis recommended. All those measures have to be supported by informationcampaigns which aim on both commercial and private customers.

  • 107.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Svensson, Gilbert
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Projekt: Fett i avloppsnät - Kartläggning och åtgärdsförslag2010Annet (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    Matfett och -olja som släpps ut till avloppsnätet kan orsaka driftproblem. Denna enkätstudie har visat att nästan alla kommuner i Norge och Sverige upplever problem på grund av fettet.

  • 108.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Zinger, Yaron
    Monash University, Melbourne, VIC.
    Deletic, Ana
    Monash University, Melbourne, VIC.
    Fletcher, Tim D.
    Monash University, Melbourne, VIC.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Effect of retrofitting a saturated zone om the performance of biofiltration for heavy metal removal: preliminary results of a laboratory study2010Inngår i: NOVATECH 2010: 7th International conference on sustainable techniques and strategies in urban water management, Lyon, France, June 27 - July 1st, 2010, Villeurbanne: Graie , 2010Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Stormwater biofilters are a stormwater treatment technology which has been becoming increasingly popular. Recently it has been shown that a submerged zone in the filter media improves the magnitude and consistency of nitrogen treatment. Furthermore, the submerged zone has even been shown to be beneficial for retention of heavy metals, particularly Cu. However, most existing biofilters do not include a saturated zone. Since it is relatively simple to retrofit a submerged zone by elevating the outflow, the effect of such a retrofitting on metal removal was investigated in this laboratory study using biofilter columns. It has been shown that a retrofitted submerged zone has a statistically significant but practically small effect on metal removal: Zn removal is slightly enhanced while the effect on Cu removal is inconsistent. Thus, retrofitting of a submerged zone is not recommended if metals are the main target pollutants. But if a submerged zone would have other benefits (e.g. for nitrogen removal or to protect the system from prolonged drying periods) it can be retrofitted without compromising metal removal.

  • 109. Blecken, Godecke-Tobias
    et al.
    Zinger, Yaron
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Deletic, Ana
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Fletcher, Tim D.
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Impact of a submerged zone and a carbon source on heavy metal removal in stormwater biofilters2009Inngår i: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 35, nr 5, s. 769-778Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biofilters are an effective treatment option for the substantial heavy metal loads in urban stormwater. However, to increase their nitrogen treatment efficacy, the introduction of a submerged (anoxic) zone (SZ) and a cellulose based carbon source (C) has been recommended because it has been shown to enhance denitrification and thereby increase overall nitrogen removal. To examine the impact of this design modification on heavy metal treatment, a laboratory study using biofilter mesocosms with different levels of SZ and with or without added C was conducted. The results show that SZ and C have a significant impact on metal treatment. In particular, the removal of Cu was improved significantly. The presence of SZ and C allows outflow Cu concentrations to meet Swedish and Australian water quality guidelines, which are not met with a standard biofilter without SZ or C. Although Zn and Pb removal was enhanced slightly by the presence of a SZ, this improvement is of less practical importance, since Zn and Pb removal is already very high (>95%) in standard biofilters. The best metal treatment was achieved with 450 and 600 mm SZ. Based on these results, the incorporation of SZ with C in stormwater biofilters is recommended.

  • 110.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Zinger, Yaron
    Monash University, Melbourne, VIC.
    Deletic, Ana
    Monash University, Melbourne, VIC.
    Fletcher, Tim D
    Monash University, Melbourne, VIC.
    Viklander, Maria
    Laboratory studies on metal treatment efficiency of stormwater biofilters2010Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Stormwater biofilters are a reliable technology to remove metals from stormwater. A solid carbon source in the filter (combined with a submerged zone) enhances especially Cu removal further; the already high Pb and Zn removal is slightly enhanced. However, the submerged zone helps to minimize (Cu, Zn) or eliminate (Pb) the negative effects which prolonged drying has on the removal rates. Thus, the introduction of a submerged zone is only recommended if nitrogen treatment is targeted (Zinger et al. 2007) or if drying is expected. Temperature differences might have a little influence on especially Cu treatment. However, this influence is not of practical importance indicating that biofilters can successfully be implemented throughout the whole seasonal cycle. A high proportion of metals are retained at the top of the filter which is important for biofilter design and maintenance planning. A filter less than the currently recommended 800 to 900 mm might be sufficient for reliable metal treatment. Furthermore, scraping of the top layer could delay replacing of the whole filter media

  • 111.
    Blecken, Godecke-Tobias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Zinger, Yaron
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Deletic, Ana
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Fletcher, Tim
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Hedström, Annelie
    Viklander, Maria
    Laboratory study on stormwater biofiltration: nutrient and sediment removal in cold temperatures2010Inngår i: Journal of Hydrology, ISSN 0022-1694, E-ISSN 1879-2707, Vol. 394, nr 3-4, s. 507-514Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Stormwater biofilters have the ability to remove nutrients from stormwater. Reliable pollutant removal during the cold season is particularly important due to the comparably high contamination levels. However, the removal performance might be negatively affected by low temperatures. A biofilter column study was conducted in thermostat-controlled climate rooms (at 2, 7 and 20 °C) to investigate the effect of low temperatures on nutrient removal. Phosphorus and suspended solids removal were significantly correlated and consistently very high (typically in excess of 90 and 95%, respectively, at all temperatures). This is important for the successful implementation of biofilters in cold climates since phosphorus is commonly of principal concern, often being the limiting factor for eutrophication in freshwater ecosystems. Unfortunately, nitrogen removal was poor and leaching was shown, which increased with temperature. The increasing nitrate-nitrogen production rates with temperature were well described by the Arrhenius relationship with temperature coefficients Q10 in the range which is typically used to describe temperature effects on nitrification. Thus, temperature effects have to be considered when nitrogen removal is targeted and the biofilter might be exposed to cold temperatures.

  • 112. Blecken, Godecke-Tobias
    et al.
    Zinger, Yaron
    Monash University, Melbourne, VIC.
    Deletic, Ana
    Monash University, Melbourne, VIC.
    Fletcher, Tim
    Monash University, Melbourne, VIC.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Heavy metal removal by stormwater biofilters: can it withstand alternative drying and wetting conditions?2008Inngår i: Conference Proceedings : 11th International Conference on Urban Drainage: Edinburgh International Conference Centre, Scotland : 11 ICUD: 31st August - 5th September 2008, Munich: Oldenbourg Industrieverlag , 2008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Urban stormwater contains substantial loads of Cu, Pb and Zn, which are considered as key stormwater contaminants. Stormwater biofiltration is a promising option to treat these contaminants. Biofilters are exposed to an alternate cycle of drying and wetting, and the influence of this on pollutant removal performance is as-yet unknown. To investigate the effect of drying and subsequent rewetting on the retention of heavy metals by stormwater biofilters, a laboratory study has been conducted using three groups of biofilter columns, which were dosed with semi-synthetic stormwater according to three different drying and wetting regimes. Some biofilters were fitted with a submerged zone combined with a carbon source, at the bottom of the filter. Overall, the biofilters were very effective in heavy metal removal, provided that they received regular stormwater input. However, after drying extending to three or four weeks, removal of heavy metals decreased significantly. A statistically significant correlation between antecedent dry days and metal removal was shown. Furthermore, a clear effect of the submerged zone was found: after extended dry periods, biofilters with this feature performed significantly better than those without it. In particular, the removal of Cu was clearly increased both during wet and dry periods; for Pb the negative effect of drying was completely eliminated by introducing a submerged zone.

  • 113. Blecken, Godecke-Tobias
    et al.
    Zinger, Yaron
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Deletic, Ana
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Fletcher, Tim
    Facility for Advancing Water Biofiltration, Department of Civil Engineering, Monash University.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Influence of intermittent wetting and drying conditions on heavy metal removal by stormwater biofilters2009Inngår i: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 43, nr 18, s. 4590-4598Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biofiltration is a technology to treat urban stormwater runoff which conveys pollutants, including heavy metals. However, the variability of metals removal performance in biofiltration systems is as yet unknown.A laboratory study has been conducted with vegetated biofilter mesocosms, partly fitted with a submerged zone at the bottom of the filter combined with a carbon source. The biofilters were dosed with stormwater according to three different dry/wet schemes, to investigate the effect of intermittent wetting and drying conditions on metal removal.Provided that the biofilters received regular stormwater input, metal removal exceeded 95%. The highest metal accumulation occurs in the top layer of the filter media.However, after antecedent drying before a storm event exceeding three to four weeks the filters performed significantly worse, although metal removal still remained relatively high. Introducing a submerged zone into the filter improved the performance significantly after extended dry periods. In particular, copper removal in filters equipped with a submerged zone was increased by around 12% (α = 0.05) both during wet and dry periods and for lead the negative effect of drying could completely be eliminated, with consistently low outflow concentrations even after long drying periods.

  • 114. Blecken, Godecke-Tobias
    et al.
    Zinger, Yaron
    Monash University, Melbourne, VIC.
    Muthanna, Tone M.
    Norwegian Institute for Water Research (NIVA), Trondheim.
    Deletic, Ana
    Monash University, Melbourne, VIC.
    Fletcher, Tim D.
    Monash University, Melbourne, VIC.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    The influence of temperature on nutrient treatment efficiency in stormwater biofilter systems2007Inngår i: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 56, nr 10, s. 83-91Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nutrients can cause eutrophication of natural water bodies. Thus, urban stormwater which is an important nutrient source in urbanised areas has to be treated in order to reduce its nutrient loads. Biofilters which use soil filter media, biofilms and plants, are a good treatment option for nutrients. This paper presents the results of a biofilter column study in cold temperatures (+2 °C, +8 °C, control at +20 °C) which may cause special problems regarding biofilter performance. It was shown that particle-bound pollutants as TSS and a high fraction of phosphorus were reduced well without being negatively influenced by cold temperatures. Nitrogen, however, was not reduced; especially NOx was produced in the columns. This behaviour can be explained with both insufficient denitrification and high leaching from the columns

  • 115.
    Borris, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Future trends in urban stormwater quality: effects of changes in climate, catchment characteristics and processes and socio-economic factors2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Climate change and progressing urbanization cause numerous environmental concerns, including the impacts on urban drainage. Such impacts were addressed during the last two decades with focus on hydraulic overloading of drainage systems and the means of overload remediation by stormwater management. However, modern urban drainage also serves to provide and protect broad environmental services chiefly by controlling stormwater quality. During the past 40 years, a sizeable investment has been made in urban drainage systems to improve stormwater quality and protect receiving water ecosystems. Such investments are at risks, because of impaired performance of stormwater quality controls now and in the future for the following reasons: (i) Hydraulic and Pollution overloading (ii) the aging of stormwater management systems and (iii) insufficient attention paid to socio-economic issues. The primary objectives of the thesis that follows is to address the above issues by examining future trends in stormwater quality and the influential factors affecting these trends. Trends in urban stormwater quality, in response to projected changes in the climate, urban catchments and their drainage systems, and environmental practices and policies, were studied by systematically describing these changes by a set of scenarios, which were then applied to several test catchments in simulations with two well-established computer models of urban drainage (US EPA SWMM and WinSLAMM). In runoff simulations, stormwater quality was described Total suspended solids (TSS) and three heavy metals, namely Cu, Pb and Zn. The assessment of uncertainties in the simulation process and potential changes in sewer pipe materials further inspired two additional studies: Potential improvements in modelling trace metal transport and control by clarifying the role of coarse sediments on road surfaces, and water quality implications of using sewer pipes made from three different materials. Simulations with up-scaled rainfall data produced changes in stormwater quality, depending on the type of storm events. Generally pollutant loads increased due to climate changes characterized by higher depths and intensities of rainfall in future scenarios. Storms with low to intermediate depths and intensities showed the highest sensitivities to climatic changes, because runoff producing areas increased with higher storm intensities (i.e., leading to contributions of pervious areas), and sufficient pollutant supplies on catchment surfaces; for high intensity events, such supplies were quickly exhausted. TSS loads exported from catchments with low imperviousness were most sensitive to climatic changes, but the magnitudes of TSS loads were low compared to those from catchments with high imperviousness. Furthermore, potential changes in catchment characteristics and drainage systems were identified to be of importance. Future scenarios combining changes in climate and socio-economic factors showed that the impacts on stormwater quality caused by climatic changes were smaller than those caused by changes in socio-economic factors. However, future urbanization impacts on stormwater quality could be controlled by incorporating modern stormwater management measures in future catchments. Simulations of such controls indicated that they were highly effective in protecting the stormwater quality. Finally it was noted that the two applied computer models produced somewhat different results and high uncertainties when assessing the future stormwater quality. This was due to their different descriptions of the underlying processes. Hence, it was desirable to examine the feasibility of improving stormwater quality modelling, particularly with respect to heavy metals. During laboratory experiments coarse particles were identified to potentially release significant amounts of heavy metals (mostly in the particulate bound phase) during runoff events. Site/runoff event specific factors (e.g., traffic intensity and street sweeping routines) and characteristics of the particles (i.e. organic content) were identified as influential factors affecting the release of heavy metals. This finding may help improve the description of pollutant transport processes in stormwater quality models. Laboratory experiments showed that various pipe materials (PVC, concrete and corrugated steel) affected the stormwater quality differently, depending on the characteristics of the stormwater used in experiments. The concrete pipe contributed to increase pH of the transported stormwater. Metal concentrations were mostly unaffected in the PVC pipe, decreased in the concrete pipe (due to particle deposition and metal adsorption to the pipe surface), and while Zn concentrations increased in the corrugated steel pipe due to elution, Cu and Pb concentrations were reduced (due to particle deposition in the corrugations). Since the impact of climatic changes on stormwater quality was relatively small compared to changes in socio-economic factors, future efforts to maintain or improve stormwater quality should focus on implementing pollutant abatement strategies, including implementation of well-designed and maintained stormwater treatment measures.

  • 116.
    Borris, Matthias
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Influential factors in simulations of future urban stormwater quality: Climate change, progressing urbanization and environmental policies2013Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Climate change is regarded as one of the main future challenges implyingchanging hydrological conditions in urban areas. At the same time many urbanareas are expected to grow due to increasing population, which will most likelycause a higher level of urbanization. Combined effects of climatic changes andprogressing urbanization will have an impact on the abundance of pollutantsand the capacity for their transport. Due to this it is most likely that stormwaterquality will change as well. Effects of climatic changes, progressingurbanization and changing environmental policies on urban stormwater qualitywere studied by means of computer simulations for different test catchments inSweden. Scenarios accounting for such changes were developed and simulatedwith the Storm Water Management Model (SWMM), in which stormwaterquality was described by total suspended solids (TSS) and two heavy metals,namely copper and zinc. The simulation results showed that pollutant loadsdepended mainly on rainfall depth and intensity, but not on antecedent periods.Storms with low to intermediate depths and intensities showed the highestsensitivities to climatic changes and the reason for that was the contribution ofpervious areas and pollutant supply limited conditions. Catchments with lowimperviousness were most sensitive to climatic changes, but the total TSSloads were low compared to catchments with high imperviousness. Generallypollutant loads increased due to climatic changes characterized by higherdepths and intensities of rainfall in future scenarios. Furthermore stormwaterquality changed significantly for scenarios considering a progressingurbanization. A changing catchment area and impervious fraction caused highchanges in runoff volumes and pollutant loads. Thus changes in suchcatchment characteristics were identified as the most influential factors; inmost of the cases changes caused by climate change were exceeded.Environmental policies, as for example the reduction of directly connectedimpervious areas were effective in reducing runoff volumes and consequentlypollutant loads. Furthermore pollutant source controls, including materialsubstitution, were identified to be an effective tool for reducing pollutant loadsand improving stormwater quality. Generally changes produced by climaticchanges were small compared to the effects of changes in land use and this hasimplications for the management of stormwater quality.

  • 117.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Gustafsson, Anna-Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Continuous simulations of urban stormwater runoff and total suspended solids loads: influence of varying climatic inputs and catchment imperviousness2014Inngår i: Journal of Water and Climate, ISSN 2040-2244, Vol. 5, nr 4, s. 593-609Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Potential implications of climate change for future stormwater management were addressed by undertaking continuous simulations of runoff and total suspended solids (TSS) loads for three urban catchments, with imperviousness varying from 23 to 63%, which were exposed to five rainfall regimes during the snow-free part of the year: the current climate and four climate change scenarios projecting higher rainfalls. Simulated runoff volumes increased in all the future scenarios, particularly in the sub-arctic climate and the fixed uplift scenario (plus20) indicating appreciable rainfall increases. Simulated runoff volumes increased depending on the projected increases in rainfall and increasing runoff contributions from pervious areas when more intense future rainfalls exceeded hydrologic abstractions. The increased runoff volumes then contributed higher TSS loads, which were highly variable for the rainfall regimes tested. In cold climate regions, residues of solids from winter road maintenance may contribute to high initial accumulations of TSS on the catchment surface and high washed off loads. In general, the study suggests that intermediate design-life stormwater management facilities require flexible design allowing for future step-wise adaptation by gradually increasing design capacities and modifying treatment trains.

  • 118.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Source-based modeling of stormwater quality response to projected future changes in climatic and socio-economic factors2015Inngår i: Urban Drainage Modelling 2015: Poster presentations : Proceedings of the 10th International Conference of Urban Drainage Modelling, Mont-Sainte-Anne, Québec, Canada 20-23 Swptember 2015 / [ed] Thomas Maere; Sovanna Tik; Sophie Duchense; Peter A. Vanrolleghem, 2015, s. 73-78Konferansepaper (Annet vitenskapelig)
  • 119.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Source-Based Modeling Of Urban Stormwater Quality Response to the Selected Scenarios Combining Future Changes in Climate and Socio-Economic Factors2016Inngår i: Environmental Management, ISSN 0364-152X, E-ISSN 1432-1009, Vol. 58, nr 2, s. 223-237Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The assessment of future trends in urban stormwater quality should be most helpful for ensuring the effectiveness of the existing stormwater quality infrastructure in the future and mitigating the associated impacts on receiving waters. Combined effects of expected changes in climate and socio-economic factors on stormwater quality were examined in two urban test catchments by applying a source-based computer model (WinSLAMM) for TSS and three heavy metals (copper, lead, and zinc) for various future scenarios. Generally, both catchments showed similar responses to the future scenarios and pollutant loads were generally more sensitive to changes in socio-economic factors (i.e., increasing traffic intensities, growth and intensification of the individual land-uses) than in the climate. Specifically, for the selected Intermediate socio-economic scenario and two climate change scenarios (RSP = 2.6 and 8.5), the TSS loads from both catchments increased by about 10 % on average, but when applying the Intermediate climate change scenario (RCP = 4.5) for two SSPs, the Sustainability and Security scenarios (SSP1 and SSP3), the TSS loads increased on average by 70 %. Furthermore, it was observed that well-designed and maintained stormwater treatment facilities targeting local pollution hotspots exhibited the potential to significantly improve stormwater quality, however, at potentially high costs. In fact, it was possible to reduce pollutant loads from both catchments under the future Sustainability scenario (on average, e.g., TSS were reduced by 20 %), compared to the current conditions. The methodology developed in this study was found useful for planning climate change adaptation strategies in the context of local conditions.

  • 120.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Gustafsson, Anna-Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    National Water Research Institute, Environment Canada.
    Modelling the effects of changes in rainfall event characteristics on TSS loads in urban runoff2014Inngår i: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 28, nr 4, s. 1787-1796Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of changes in rainfall event characteristics on urban stormwater quality, which was described by total suspended solids (TSS), was studied by means of computer simulations conducted with the Storm Water Management Model for a climate change scenario for northern Sweden. The simulation results showed that TSS event loads depended mainly on rainfall depth and intensity, but not on antecedent conditions. Storms with low-to-intermediate depths and intensities showed the highest sensitivity to changes in rainfall input, both for percentage and absolute changes in TSS wash-off loads, which was explained by the contribution of pervious areas and supply limitations. This has significant implications for stormwater management, because those relatively frequent events generally carry a high percentage of the annual pollutant load

  • 121.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Gustafsson, Anna-Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Simulating future trends in urban stormwater quality for changing climate, urban land use and environmental controls2013Inngår i: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 68, nr 9, s. 2082-2089Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effects of climatic changes, progressing urbanization and improved environmental controls on the simulated urban stormwater quality in a northern Sweden community were studied. Future scenarios accounting for those changes were developed and their effects simulated with the Storm Water Management Model (SWMM). It was observed that the simulated stormwater quality was highly sensitive to the scenarios, mimicking progressing urbanization with varying catchment imperviousness and area. Thus, land use change was identified as one of the most influential factors and in some scenarios, urban growth caused changes in runoff quantity and quality exceeding those caused by a changing climate. Adaptation measures, including the reduction of directly connected impervious surfaces (DCIS) through the integration of more green spaces into the urban landscape, or disconnection of DCIS were effective in reducing runoff volume and pollutant loads. Furthermore, pollutant source control measures, including material substitution, were effective in reducing pollutant loads and significantly improving stormwater quality

  • 122.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Gustafsson, Anna-Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Using urban runoff simulations for addressing climate change impacts on urban runoff quality in a Swedish town2012Inngår i: Urban Drainage Modelling: Proceedings of the Ninth International Conference on Urban Drainage Modelling, Belgrade, Serbia, 4-6 September 2012, Belgrade: Faculty of Civil Engineering, University of Belgrade , 2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The effect of climate change on urban stormwater quality was studied by means of computer simulations conducted with the Stormwater Management Model (SWMM) for common climate change scenarios developed for northern Sweden. The simulation results showed that stormwater quality depended on rainfall characteristics; a climate scenario implying increased rainfall depths and intensities produced higher pollutant loads carried by stormwater, but reduced concentrations, particularly for medium to high intensity storm events. This type of stormwater quality response was explained by pollutant supply limited transport processes and the resulting dilution of such pollutants. Medium intensity events showed the highest sensitivity to climatic changes, since such events strongly affected the contributions of pervious surfaces. This has significant implications for stormwater management, because those relatively frequent events generally carry a high percentage of the annual pollutant load.

  • 123.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    An exploratory study of the effects of stormwater pipeline materials on transported stormwater quality2017Inngår i: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 76, nr 2, s. 247-255Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Implications of three sewer pipe materials (concrete, galvanized corrugated steel, and polyvinyl chloride (PVC)) for stormwater quality were explored in laboratory experiments, in which three types of stormwater, SW1-SW3, were circulated in 0.5 m long sewer pipe sections. SW1 and SW2 represented synthetic rainwater, without and with fine street sediment added (CTSS = 150 mg/L), respectively, and SW3 was actual stormwater with the same sediment addition as SW2. Following 20-min runs, with an equivalent distance of 500 m travelled by water particles, a number of statistically significant changes in the stormwater chemistry were observed: (i) pH of all the simulated stormwaters increased in the concrete pipe (from 7.0-7.3 to 8.1-9.3), (ii) turbidity decreased in two stormwaters with sediments (SW2 and SW3) in concrete and galvanized corrugated steel pipes (by 50 and 85%, respectively), (iii) the type of stormwater affected the observed copper (Cu) concentrations, with Cudiss concentrations as high as 25.3 μg/L noted in SW3 passing through the PVC pipe, and (iv) zinc (Zn) concentrations sharply increased (Zntot = 759-1,406 μg/L, Zndiss = 670-1,400 μg/L) due to Zn elution from the galvanized steel pipe by all three stormwaters. Such levels exceeded the applicable environmental guidelines.

  • 124.
    Borris, Matthias
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Contribution of coarse particles from road surfaces to dissolved and particle-bound heavy metal loads in runoff: A laboratory leaching study with synthetic stormwater2016Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 573, s. 212-221Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Laboratory leaching experiments were performed to study the potential of coarse street sediments (i.e. > 250 μm) to release dissolved and particulate-bound heavy metals (i.e. Cd, Cr, Cu, Ni, Pb and Zn) during rainfall/runoff. Towards this end, street sediments were sampled by vacuuming at seven sites in five Swedish cities and the collected sediments were characterized with respect to their physical and chemical properties. In the laboratory, the sediments were combined with synthetic rainwater and subject to agitation by a shaker mimicking particle motion during transport by runoff from street surfaces. As a result of such action, coarse street sediments were found to release significant amounts of heavy metals, which were predominantly (up to 99%) in the particulate bound phase. Thus, in dry weather, coarse street sediments functioned as collectors of fine particles with attached heavy metals, but in wet weather, metal burdens were released by rainfall/runoff processes. The magnitude of such releases depended on the site characteristics (i.e. street cleaning and traffic intensity), particle properties (i.e. organic matter content), and runoff characteristics (pH, and the duration of, and energy input into, sediment/water agitation). The study findings suggest that street cleaning, which preferentially removes coarser sediments, may produce additional environmental benefits by also removing fine contaminated particles attached to coarser materials

  • 125.
    Boström, Victor
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Lokaliseringsutredning av tankstationer med hjälp av GIS: En fallstudie av Luleå2017Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Sweden’s national goal to have all vehicles to be zero emission vehicles by year 2030 puts high demands on the infrastructure of alternative fuels. Most cities in developed countries already have a working infrastructure for conventional fuels that has been planned with regard to its unique conditions, such as traffic and population density. These conditions of a city are surely not going to change even if every car was replaced by a zero emission vehicle. Today’s infrastructure for conventional fuels is therefore suitable also for alternative fuels.

    Electric vehicles on the other hand takes much more time to reload than it takes to refuel a normal car, which makes service stations less suitable locations for charging them. Electric vehicles’ relatively short range (150-600 km) will most probably not affect how a city’s inhabitants move within the city.

    In this master thesis the existing infrastructure for both conventional and alternative fuels for public consumption is analyzed, with the purpose to improve its accessibility. The thesis is supposed to facilitate the Municipality of Luleå’s planning before establishing new service stations. The method results in a couple of proposed areas that would benefit the fuel accessibility the most, both to its citizens and to commuters of other cities.

    Keywords: fuel, gas station, Network Analyst

  • 126.
    Broekhuizen, Ico
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Uncertainties in rainfall-runoff modelling of green urban drainage systems: Measurements, data selection and model structure2019Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Green urban drainage systems are used to avoid flooding and damages to people and property, while limiting the downstream flooding and water quality problems caused by pipe-based drainage systems. Computer models are used to analyse and predict the performance of such systems for design and operation purposes. Such models are simplifications of reality and based on uncertain measured data, so uncertainties will be involved in the modelling process and its outcomes, which can affect the design and operation of these systems. These uncertainties have been investigated extensively for traditional pipe-based urban drainage systems, but not yet for green alternatives. Therefore, the overall objective of this thesis is to contribute to improved applicability and reliability of computer models of green urban drainage systems. Specifically, the thesis aims to (1) improve understanding of the uncertainties arising from (a) model structure and (b) calibration data selection, (2) evaluate two alternative calibration methods for green urban drainage models, (3) discuss desirable structural features in urban drainage models, and (4) evaluate several sensors for hydrometeorological measurements in urban catchments.

    The effects of model structure uncertainty were investigated using long-term simulations of synthetic catchments with varying soil types and depths for three different models. First, it was found that surface runoff could be a significant part of the annual water balance in all three models, depending on the soil type and depth considered. Second, differences were found in how sensitive the different models were to changes in soil type and depth. Third, the variation between different models was often large compared to the variation between different soil types. Fourth, the magnitude of inter-annual and inter-event variation varied between the models. Overall, the findings indicate that significant differences may occur in urban drainage modelling studies, depending on which model is used, and this may affect the design or operation of such systems.

    The uncertainty from calibration data selection was investigated primarily by calibrating both a low- and high-resolution stormwater model using different sets of events. These event sets used different rainfall-runoff statistics to rank all observed events before selecting the top six for use in calibration. In addition, they varied by either calibrating all parameters simultaneously, or by calibrating parameters for impervious and pervious surfaces separately. This last approach sped up the calibration process. In the validation period the high-resolution models performed better than their low-resolution counterparts and the two-stage calibrations matched runoff volume and peak flows better than single-stage calibrations. Overall, the way in which the calibration events are selected was shown to have a major impact on the performance of the calibrated model.

    Calibration data selection was also investigated by examining different ways of including soil water content (SWC) observations in the calibration process of a model of a swale. Some model parameters could be identified from SWC, but not from outflow observations. Including SWC in the model evaluation affected the precision of swale outflow predictions. Different ways of setting initial conditions in the model (observations or an equilibrium condition) affected both of these findings.

    The precipitation sensors used in this thesis showed generally satisfactory performance in field calibration checks. Different types of precipitation sensors were associated with different requirements for maintenance and data acquisition. Sensors for sewer pipe flow rates showed good agreement with a reference instrument in the laboratory, as long as installation conditions were good. Higher pipe slopes and upstream obstacles lead to larger measurement errors, but this last effect was reduced by increasing water levels in the pipe. Sensor fouling was a source of errors and gaps in field measurements, showing that regular maintenance is required. The findings show that the evaluated flow sensors can perform satisfactorily, if measurement sites are carefully selected.

  • 127.
    Broekhuizen, Ico
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Calibration event selection for green urban drainage modelling2019Inngår i: Hydrology and Earth System Sciences Discussions, ISSN 1812-2108, E-ISSN 1812-2116Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Calibration of urban drainage models is typically performed based on a limited number of observed rainfall-runoff events, which may be selected from a longer time-series of measurements in different ways. In this study, 14 single- and two-stage strategies for selecting these events were tested for calibration of a SWMM model of a predominantly green urban area. The event selection was considered in relation to other sources of uncertainty such as measurement uncertainties, objective functions, and catchment discretization. Even though all 14 strategies resulted in successful model calibration, the difference between the best and worst strategies reached 0.2 in Nash–Sutcliffe Efficiency (NSE) and the calibrated parameter values notably varied. Most, but not all, calibration strategies were robust to changes in objective function, perturbations in calibration data and the use of a low spatial resolution model in the calibration phase. The various calibration strategies satisfactorily predicted 7 to 13 out of 19 validation events. The two-stage strategies performed better than the single-stage strategies when measuring performance using the Root Mean Square Error, flow volume error or peak flow error (but not using NSE); when flow data in the calibration period had been perturbed by ±40 %; and when using a lower model resolution. The two calibration strategies that performed best in the validation period were two-stage strategies. The findings in this paper show that different strategies for selecting calibration events may lead in some cases to different results for the validation period, and that calibrating impermeable and green area parameters in two separate steps may improve model performance in the validation period, while also reducing the computational demand in the calibration phase.

  • 128.
    Broekhuizen, Ico
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Marsalek, Jiri
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Selection of Calibration Events for Modelling Green Urban Drainage2019Inngår i: New Trends in Urban Drainage Modelling: UDM 2018 / [ed] Giorgio Mannina, Cham: Springer, 2019, s. 608-613Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Urban drainage models are often calibrated using a limited number of rainfall-runoff events, which may be selected in different ways from a longer observation series. This paper compares 13 different single- and two-stage strategies for selecting events used to calibrate a SWMM model of a predominantly green urban area. Most led to successful calibration, but performance varied for various validation events. Most selection strategies were insensitive to the choice of Nash-Sutcliffe Model Efficiency or Root Mean Squared Error as the objective function. Calibrating impervious and green area parameters separately in two-stage strategies can help improve prediction of low-flow events in validation.

  • 129.
    Broekhuizen, Ico
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Muthanna, Tone M.
    Norwegian University of Science and Technology, Trondheim, Norway.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Urban drainage models for green areas: Structural differences and their effects on simulated runoff2019Inngår i: Journal of Hydrology X, ISSN 2589-9155, Vol. 5, artikkel-id 100044Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mathematical stormwater models are often used as tools for planning and analysing urban drainage systems. However, the inherent uncertainties of the models must be properly understood in order to make optimal use of them. One source of uncertainty that has received relatively little attention, particularly for increasingly popular green areas as part of urban drainage systems, is the mathematical model structure. This paper analyses the differences between three different widely-used models (SWMM, MOUSE and Mike SHE) when simulating rainfall runoff from green areas over a 26-year period. Eleven different soil types and six different soil depths were used to investigate the sensitivity of the models to changes in both. Important hydrological factors such as seasonal runoff and evapotranspiration, the number of events that generated runoff, and the initial conditions for rainfall events, varied significantly between the three models. MOUSE generated the highest runoff volumes, while it was rather insensitive to changes in soil type and depth. Mike SHE was mainly sensitive to changes in soil type. SWMM, which generated the least runoff, was sensitive to changes in both soil type and depth. Explanations for the observed differences were found in the descriptions of the mathematical models. The differences in model outputs could significantly impact the conclusions from studies on the design or analysis of urban drainage systems. The amount and frequency of runoff from green areas in all three models indicates that green areas cannot be simply ignored in urban drainage modelling studies.

  • 130.
    Broekhuizen, Ico
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten. Luleå Tekniska Universitet.
    Muthanna, Tone Merete
    Norwegian University of Science and Technology.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Model structure uncertainty in green urban drainage modelsManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Mathematical storm water models are often used as tools for planning and analysis of urban drainage systems, but the models’ inherent uncertainties need to be understood to make optimal use of them. One source of uncertainty that has received relatively little attention, especially for the increasingly popular green areas as part of urban drainage systems, is the choice of the mathematical model structure. This paper analyses the differences between three different widely-used models (SWMM, MIKE MOUSE and MIKE SHE) when simulating green areas over a 26 year period. A wide range of eleven different soil types and six different soil depths was used to investigate sensitivity of the models to changes in both. Important hydrological factors such as seasonal runoff and evapotranspiration, the number of events that generated runoff, and the initial conditions for rainfall events, varied strongly between the three models. MOUSE generated the highest runoff and was insensitive to changes in soil type and depth, while SHE was sensitive mainly to changes in soil type, and SWMM, which generated the least runoff, was sensitive to changes in both soil type and depth. Explanations for the observed differences were found in the descriptions of the mathematical models. The differences in model outputs could significantly impact the conclusions from design or analysis studies of urban drainage systems. The amount and frequency of runoff from green areas in all three models indicates that green areas cannot be simply ignored in urban drainage modelling studies.

  • 131.
    Broekhuizen, Ico
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Muthanna, Tone Murete
    Norwegian University of Science and Technology.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Model structure uncertainty in urban drainage models for green areas2017Inngår i: 14th IWA/IAHR International Conference on Urban Drainage: Conference Proceedings, 2017, Prague, 2017, s. 1490-1494Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Two urban drainage models (SWMM and MOUSE) were used to study the impact of model structureuncertainty on long-term simulation of green areas. Depending on the soil profile being consideredsignificant differences were observed between the models, both on an annual and event basedscale. In general MOUSE generates more runoff and is more sensitive to changing soil depth. Thedifferences can be explained by the conceptual approaches used to model infiltration, which alsoaffects how much water is apportioned to evapotranspiration, surface runoff, and baseflow.

  • 132.
    Broekhuizen, Ico
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Rujner, Hendrik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Roldin, Maria
    DHI Sweden.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Towards using soil water content observations for calibration of distributed urban drainage models2019Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Fully distributed urban drainage models can be used to analyse and predict the behaviour of green urban drainage infrastructure such as swales, but they need to be calibrated for specific study sites. Using only drainage outflow measurements may not provide enough information to do this in an optimal way, so additional types of measurements have to be considered. This study identifies different approaches to including soil water content (SWC) observations in the calibration process and investigates how they affect parameter identifiability and the predictive uncertainty of the calibrated model. This is done using the Generalized Likelihood Uncertainty Estimation methodology applied to a model of a large urban swale. It was found that setting initial conditions based on the SWC measurements improved the fit between observed and simulated SWC, but also reduced the accuracy of the simulated amount of infiltration. Including SWC observations allowed to identify one parameter (saturated moisture content of the swale bottom) that was not identifiable from outflow measurements alone. Including SWC observations in the derivation of predictive uncertainty bounds made those bounds narrower (more precise), but where SWC had been used to set initial conditions the uncertainty bound failed to capture the observations. It is concluded that SWC observations can provide useful information for the calibration of distributed urban drainage models.

  • 133.
    Brännström, Hugo
    et al.
    Luleå tekniska universitet.
    Eriksson, Gunnar
    Lundborg, Glenn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hanaeus, Jörgen
    Nordell, Bo
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Systemutredning: flöden och miljöeffekter : Luleå gymnasieby1998Rapport (Annet vitenskapelig)
  • 134.
    Burger, Gregor
    et al.
    Unit of Environmental Engineering, University of Innsbruck.
    Bach, Peter M.
    Monash Infrastructure Research Institute, Monash University, Melbourne, VIC, Cooperative Research Centre (CRC) for Water Sensitive Cities.
    Urich, Christian
    Unit of Environmental Engineering, University of Innsbruck, CRC for Water Sensitive Cities, Monash University, Melbourne, VIC.
    Leonhardt, Günther
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten. Unit of Environmental Engineering, University of Innsbruck.
    Kleidorfer, Manfred
    Unit of Environmental Engineering, University of Innsbruck.
    Rauch, Wolfgang
    Unit of Environmental Engineering, University of Innsbruck.
    Designing and implementing a multi-core capable integrated urban drainage modelling Toolkit: Lessons from CityDrain32016Inngår i: Advances in Engineering Software, ISSN 0965-9978, E-ISSN 1873-5339, Vol. 100, s. 277-289Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Integrated urban drainage modelling combines different aspects of the urban water system into a common framework. With increasing pressures of a changing climate, urban growth and economic constraints, the need for wider spread integration is necessary in the interest of a sustainable future. Greater complexity results in greater computational burden but modelling packages will, likewise, need to be flexible enough to allow incorporation of new algorithms. With advancements in modern information technology, a parallel implementation of such a modelling toolkit is mandatory while still leaving its users the flexibility of extensions. The design and implementation of the integrated modelling framework CityDrain3 shows that it is possible to write research code that is high-performance and extensible by many research projects. Three use case scenarios are presented to showcase the application of CityDrain3. The performance advantage of parallelization (up to 40 times compared to its predecessor) and the scalability of the framework are also demonstrated.

  • 135.
    Bäckström, Lars
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Industriell Ekonomi.
    Berggård, Glenn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Gedda, Oskar
    Luleå tekniska universitet, Institutionen för konst, kommunikation och lärande, Pedagogik språk och Ämnesdidaktik.
    Persson, Anders J
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Arbetsvetenskap.
    Prellwitz, Maria
    Luleå tekniska universitet, Institutionen för hälsovetenskap, Hälsa och rehabilitering.
    Weber, Hans
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Materialvetenskap.
    Wikberg-Nilsson, Åsa
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Innovation och Design.
    Det uppkopplade samhället och högre utbildning2014Inngår i: NU 2014: Umeå 8-10 oktober : abstracts, Umeå: Umeå universitet. Pedagogiska institutionen , 2014, s. 123-Konferansepaper (Fagfellevurdert)
  • 136.
    Bäckström, Magnus
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Johansson, Daniel
    Mälarenergi AB.
    Marklund, Stefan
    Luleå kommun.
    Ylinenpää, Jan-Eric
    Luleå kommun.
    Luftspolning av tryckavloppsledningar för bekämpning av svavelväte2010Rapport (Annet vitenskapelig)
    Abstract [sv]

    Luftspolning av tryckavloppsledningar har utprovats som ett alternativ för att förhindra svavelvätebildning i avloppsnätet. Syftet med luftspolningen är att tömma tryckledningen på spillvatten och på detta sätt förkorta uppehållstiden samtidigt som de sulfidbildande mikroorganismerna i ledningen får ett betydligt tuffare liv. Fullskaleförsök visar att luftspolning är ett realistiskt och fungerande alternativ för bekämpning av svavelväte i avloppsnät. Luftspolningstekniken har dock sina begränsningar, som då tryckavloppsledningen har tydliga höjdpunkter och svackor.

  • 137. Bäckström, Magnus
    et al.
    Malmqvist, Per-Arne
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Stormwater management in a catchbasin perspective - best practices or sustainable strategies?2002Inngår i: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 46, nr 6-7, s. 159-166Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A strategy for sustainable stormwater management is needed. This study has focused on the relative importance of stormwater as a pollutant source in a catchbasin, if Best Management Practices (BMPs) result in pollutant removal or pollutant redistribution, and methods for screening of stormwater strategies. Stormwater is most likely an important pathway for pollutants in a catchbasin perspective. True pollutant removal can only be achieved if the pollutant sources are eliminated. Until that is reached, we should have the best possible control of the pollutant fluxes in the watershed. This study indicates that the search for a sustainable stormwater strategy could be easier to handle if different "screens" could be used. The Swedish environmental objectives, which try to encapsulate all aspects of sustainability, may be used as a foundation for a "sustainability screen". By using this screen, the "unsustainable" features of different stormwater strategies could be pointed out. A "standards and legislation screen" will be based on the EU Water Framework Directive. As this study has shown, it is doubtful whether the conventional BMPs, such as stormwater ponds and infiltration facilities, produce a sufficient pollutant control.

  • 138. Bäckström, Magnus
    et al.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Integrated stormwater management in cold climates2000Inngår i: Journal of Environmental Science and Health. Part A: Toxic/Hazardous Substances and Environmental Engineering, ISSN 1093-4529, E-ISSN 1532-4117, Vol. 35, nr 8, s. 1237-1249Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Integrated stormwater management is based on the natural processes in the water cycle and the criteria for sustainable development. The aim of this paper was to investigate which integrated stormwater system components might be suitable in cold climate regions. The evaluation was based on literature reviews and studies made in Lulea, Northern Sweden. It was found that porous pavement, grassed waterways (swales, ditches), wet pond, and percolation basin were the most suitable integrated stormwater system components in cold regions whereas dry basin, stormwater infiltration surfaces, and stormwater reuse seemed to be the less suitable. Polluted snow may be treated at a central (large-scale) snow deposit; cleaner snow may be placed in many local snow depots.

  • 139. Bäckström, Magnus
    et al.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Malmqvist, Per-Arne
    Chalmers University of Technology, Urban Water.
    Transport of stormwater pollutants through a roadside grassed swale2006Inngår i: Urban Water Journal, ISSN 1573-062X, Vol. 3, nr 2, s. 55-67Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Investigations of the pollutant trapping capability of a grassed swale receiving runoff from a road with a traffic intensity of 8,000 vehicles/day were carried out in central Luleå, Sweden. Transport and retention of suspended solids, particles and heavy metals (copper, lead and zinc) were analysed. The sampling was carried out during seven rain events. The results show that once pollutants are trapped in a grassed swale they are not permanently bound to vegetation or soil. A roadside grassed swale may be regarded as a stormwater treatment facility that attenuates the peaks in pollutant loads, without being capable of producing consistently high removal rates.

  • 140.
    Börestam, Harald
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Norell, Mathilda
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Samordning mellan arkitekt och vvs-projektör i programskede: En undersökning, ett förslag till arbetsmetod och ett gestaltningsexperiment.2019Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Idag ställs höga krav på gott inomhusklimat och tillfredsställande termisk komfort. Tack vare flera tekniska innovationer går det att möta dessa behov, men detta medför att installationssystemen i dagens flerbostadshus tar allt mer plats. Samtidigt som tekniken får ta mer och mer plats har utvecklingen på projekteringssidan gått i en helt annan riktning. Arkitekten har istället kommit att bli en av de många konsulter som specialiserar sig på sin del av projektet (Östnäs, 1984). Att dessa utvecklingar skett åt olika håll skapar ett kunskapsgap mellan teknikkonsulter och arkitekter i dagens byggprojekt. 54% av respondenterna i denna studie, uppger att kunskapsgapet mellan A och VVS är så stort att det skapar problem i projekteringen och 35% av respondenterna anger att det ofta bidrar negativt till slutresultatet i form av nödlösningar.

    Detta examensarbete syftar till att undersöka om samordningen mellan arkitekt och VVS-projektör kan förbättras genom att överbrygga installationskunskap. Studien begränsas till att omfatta enbart samordning mellan Arkitekt och VVS-projektör och avgränsas alltså mot övriga projektörer i ett byggprojekt. Undersökningen fokuserar på samordning i tidigt skede av projekteringen, programskede.

    Hypotesen är att det generellt finns ett behov av ökad installationssamordning i projekteringen, denna testades genom en kvantitativ undersökning i form av en webbenkät. Totalt deltog 99 personer i undersökningen. Med hjälp av statistisk analys i form av hypotestest påvisades att det generellt finns ett behov av ökad samordning, hypotesen gick att bevisa. Utöver det identifierades, med hjälp av hypotestest I, att det behövs en förändring i vilka projektörer som ingår i projektet i programskede.

    De oftast förekommande samordningsproblemen identifierades genom kvalitativa djupintervjuer med elva verksamma projektörer och två branschexperter. Här framgick att de problem som förkommer i störst utsträckning är storlekar på fläktrum och placeringar av schakt. De problem som medför störst konsekvenser var vertikala utrymmen. Orsaken till uppkomsten av problem menar många är bristande kunskap eller erfarenhet från arkitektens sida. Arkitekter i sin tur uppger att det beror på ändringar i sena skeden från beställarens eller vvs-projektörens håll. Majoriteten hävdar att om vvs-projektören kom in i ett tidigare skede så skulle problemen minska.

    Därefter utvecklades, under en workshop med 5 deltagande projektörer ett förslag till hjälpmedel. Kontentan från den workshopen var att om vvs-projektören kommer in i projektet i tidigt skede, programskede, så kan rätt förutsättningar sättas tidigt. Förslag om kreativa startmöten uppkom bland annat. Deltagarna var även överens om att det bästa sättet att förmedla installationskunskap är att utbilda, detta dels genom tvärfackliga projekt under arkitektutbildningen, dels genom kurser eller platsbesök för de praktiserande arkitekterna.

    Ur samtlig insamlad data formades ett hjälpmedel för att möta de identifierade behoven. Detta hjälpmedel blev en checklista för hur möten och konsultation mellan A och VVS ska ske i programskede. Checklistan tydliggör ansvar och förväntningar för båda parter.

    Detta hjälpmedel testades sedan experimentellt i ett gestaltningsförslag. Gestaltningsförslaget är ett flerbostadshus på fastigheten Kv. Notstället 5 & 6 i Eskilstuna kommun. I programhandlingen, som utgör resultatet av experimentet, presenteras även lösningar för installationssystem.

    Hjälpmedlets förmåga att möta de identifierade behoven utvärderades med slutsatsen att behoven tillgodoses men att ett kompletterande verktyg för ökad installationskunskap kan behövas. Hjälpmedlet anses inte bekosta projektet på arkitektoniska kvaliteter i så stor mån utan skapat mervärde genom nya innovationer samt att överraskningar undveks.

    Som forskningsämne har detta projekt väckt stort intresse i branschen. Insikter från denna studie är att tvärfacklig kommunikation och kunskapsöverföring mellan disciplinen generellt är ett intressant ämne att studera. De samlade resultaten från denna studie pekar på att en förändring i arbetsrätt under tidigare skeden i projekteringen är något som bör ske. Detta för att effektivisera projekteringen och säkerställa god kvalitet i slutprodukten, våra flerbostadshus.

  • 141.
    Candappa, Nimmi
    et al.
    Monash University Accident Research Center.
    Fotheringham, Nicola
    Monash University Accident Research Center.
    Lenné, Michael
    Monash University Accident Research Center.
    Corben, Bruce
    Monash University Accident Research Center.
    Johansson, Charlotta
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Smith, Paul
    City of Port Philip.
    Evaluation of an alternative pedestrian treatment at a roundabout2005Inngår i: Australasian Road Safety Research Policing Education Conference: Museum of New Zealand, Te Papa Tongarewa, Wellington, New Zealand, 14-16 November 2005 : peer-reviewed papers., Wellington: Ministry of Transport , 2005, s. 65-69Konferansepaper (Fagfellevurdert)
  • 142.
    Catalini, Anna
    et al.
    College of Arts, University of Lincoln.
    Nour, ZeinabFaculty of Fine Arts, Helwan University.Versaci, AntonellaFaculty of Engineering and Architecture, University “Kore” of Enna.Hawkes, DeanCambridge, UK.Bougdah, HocineCanterbury School of Architecture, University for the Creative Arts.Sotoca, AdolfLuleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.Ghoneem, MahmoudArchitecture Department, Faculty of Fine Arts, Helwan University.Trapani, FerdinandoUrban Planning, Architecture, Palermo University.
    Cities' Identity Through Architecture and Arts: Proceedings of the 1st International Conference on Cities' Identity through Architecture and Arts (CITAA 2017), Cariro, Egypt,  May 11-13, 20172018Konferanseproceedings (Fagfellevurdert)
    Abstract [en]

    Every city has its unique and valuable identity, this identity is revealed through its physical and visual form, it is seen through the eyes of its residents and users. The city develops over time, and its identity evolves with it. Reflecting the rapid and constant changes the city is subjected to, Architecture and Arts, is the embodiment of the cultural, historical, and economical characteristics of the city. This conference is dedicated for the investigation of the different new approaches developed in Architecture and Contemporary arts. It will focus on the basis of urban life and identities.

    It will discuss the examples and tendencies in dealing with urban identities as well as the transformation of cities and urban cultures mentioned in terms of their form, identity, and their current art. Contemporary art, when subjected to experiments, continues to be produced in various directions, to be consumed and to put forward new ideas. Art continuously renews itself -from new materials to different means of communication, from interactive works to computer games, from new approaches to perceptional paradigms and problems of city and nature of the millennium.

  • 143.
    Cederwall, Linnea
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Glasfasader för trämoduler2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Sammanfattning

    Modulbyggnader har utvecklats mycket under de senaste decennierna. Metoden föredras på grund av de snabba monteringstiderna och enkla installationerna. I Sverige föredras trä som bärande material för modulerna. Modulbyggnader kan många gånger upplevas som repetitiv på grund av dess återkommande fasad.

    Glasfasader kan användas för att säkerställa en arkitektonisk uppfattning och bryta det repetitiva mönstret. Syftet med examensarbetet är att undersöka hur en glasfasad med en struktur av glas och trä kan användas med en modul. Fasaden är konstruerad för att produceras industriellt och enkelt monteras ihop med andra fasadelement. Värmeförhållanden och vindbelastning antogs efter en placering i Luleå. Tjockleken på det yttre glasskiktet har utformats efter lastkombinationer, där vindtrycket var den dominerande kvasistatiska belastningen. De påfrestningar som glasskiktet utsätts för har beräknats både analytiskt och med Finita elementmetoden.

    Fasadelementet består av tre glasskivor och en träram. Den yttre glasskivan är laminerad och är 14,8 mm tjock. De andra två är härdade glasskivor med en tjocklek av 4 mm vardera och två luftspalter på 18,5 mm mellan glasskikten. De härdade glasen är behandlade med ett lågemissionsskikt. Fasadens U-värde beräknades till 0,68 W / m2K med hjälp av programmet Spectrum.

    Laminerat trä används för träramen och löper runt glasskivans fyra kanter. Varje del av ramen är utformad som en U-balk med en längd på 3 meter. Fasadelementen är anslutna till trämodulen med 8x300 mm skruvar genom U-balken. Livets tjocklek på U-sektionen dimensionerades för att undvika sprickbildning på grund av borrning och fick dimensionen 88 mm. U-balkens övre och undre fläns är 100 mm bred och har en tjocklek av 20 mm. Deras syfte är att hålla glasplattorna på plats. Mellan glaset och flänsen appliceras ett akrylatlim som förbinder materialen.

  • 144.
    Cettner, Annicka
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Byggbranschen bör ändra sin syn på "manlighet"2008Inngår i: Husbyggaren : bygg, el, VVS, anläggning, ISSN 0018-7968, nr 5, s. 48-52Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 145.
    Cettner, Annicka
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Kvinna i byggbranschen: civilingenjörers erfarenheter ur genusperspektiv2008Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis is a gender analysis based on women's experiences of working as engineers in the construction industry. It focuses on the women's working conditions, and their possibilities to make a career in construction. The question is why many women engineers choose to leave construction after an expensive education. Furthermore, there is a question of their actual working situation as engineers to find some explanations to their decision to pursue a career in construction or not. A gender perspective makes it possible to reach some of the main obstacles and get close to some contributory factors. The overall purpose of this thesis is to understand and describe women's working conditions as engineers in the construction industry. My empiricism is based on eleven in-depth interviews with women's reflections on conditions, structure and culture in construction. They all have experiences from working as engineers and made different choices in their career. The woman's perspective is very important to illustrate how the construction industry today addresses women as co-workers in an industry with lack of labour. In spite of the industry's good will it is still difficult to increase and keep women in the industry. The construction industry has been open for women for more than thirty years but the average age for women is still low. Women's attempt to get into the construction has been going on much longer than that and the struggle for equal conditions is still ongoing. It is not an easy task, many interviewed women experience that the construction industry is constructed just for men by men.My study shows that the historical traditional male construction industry is almost unchanged. Women as engineers still tend to be pioneers with limited space for working as engineers. Statistics show that women are economically subordinated. The stories of the interviewed women tell that they are subordinated in the matter of career and social fellowship. Experiences of being a different minority in a visible position are returning themes in their stories. The predominating picture in the majority of the interviews described an impenetrable social fellowship and an engineering norm with a certain kind of manliness that make women's chance to advance more difficult. They have to face up to and manage resistance and are peripheral considering power, participation and position. My study shows that the essence in the problem is about the outdated picture of the engineer, as a symbol for manliness and hegemonic masculinity. The competent engineer, whom the woman engineer has to conform to, is defined as an efficient trouble shooter keeping cool. The outdated picture of the engineer does not correspond to the modern community and the engineering work that normally is about cooperation. The norm of the engineer has an impact on and sorts out many women working in the construction industry. It affects structure and culture and it forms working conditions and working relations. My study shows that the norm infects all levels in construction with a need to define the "real" engineer and makes the confirmation a hard effort of will for a woman working there. The choice seems to stand between two stereotype models; the female model and the male model. Both offer the woman limited freedom to create a future in the construction industry. They neither give a higher salary, increased influence or entrance to the essence of the social fellowship. The overriding gender order in the community facilitates for the norm to remain. The question of why many women leave the construction industry is complex and my study gives no simple answer. But the consequences of the norm, the structure and the culture in construction all together constitute interacting explanations. It is up to the construction industry to revise and update itself to adapt to modern times. Thereby the odds to successfully increase and keep the women engineers will be improved. A possible opportunity for change could be the male culture evident in the consultant sector.

  • 146.
    Cettner, Annicka
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Kvinnors erfarenheter som civilingenjörer i byggbranschen: arbetsvillkor och genus2007Konferansepaper (Annet vitenskapelig)
    Abstract [sv]

    Min forskning handlar om att undersöka och beskriva kvinnors erfarenheter som civilingenjörer i byggbranschen. Syftet är att med ett genusperspektiv på kvinnors villkor i byggbranschen starta en fördjupad diskussion om hur och varför kvinnor väljer eller inte väljer att göra karriär inom bygg.Resultat från tidigare utförd förstudie (Berggren K., Hedman-Pétursson E., 2004) som var ett samarbetet mellan NCC Construction och Luleå tekniska universitet, visar att ca 30 % av de kvinnor som utexaminerats som civilingenjörer i Väg och vatten valde bort byggbranschen.Förstudiens resultat sammanfaller väl med den högst aktuella samhällsdebatt som betonar byggbranschens rekryteringsbehov i framtiden. Byggbranschens företrädare säger själva att de vill bredda rekryteringsunderlaget och ta in fler kvinnor. Det har även i en sorts integrerad rekryterings- och jämställdhetsanda under många år genomförts generella samhällsinsatser för att "höja kvinnors teknikintresse" och sakta har andelen kvinnor som utexamineras som civilingenjörer ökat. Men byggbranschen har fortfarande svårt att att öka andelen kvinnor samt att behålla de få som söker sig dit. Den fråga som intresserar både byggbranschen och mig (men troligen med olika perspektiv) är alltså: "Vad är det för fel på byggbranschen?".Min studie baserar sig på kvinnors erfarenheter och kvalitativa djupintervjuer utgör den huvudsakliga empiriinsamlingsmetoden. Metoden bygger på tio intervjuer med kvinnor representerade från de två dominerande sektorerna, konsultsektorn och entreprenadsektorn,. i byggbranschen där kvinnor examinerade från Väg och vatten arbetar/arbetat som civilingenjörer. Under inledande studier om genusteorier och annan forskning om kvinnor i mansdominerade arbetsorganisationer växte mina intervjuteman fram. Frågor som inriktas på kvinnornas erfarenheter av möjligheter och förutsättningar att arbeta som civilingenjörer i byggbranschen. Jag hoppas kunna belysa strukturen och kulturen i branschen och även att visa på bilden av civilingenjören. I mina preliminära resultat syns tydliga paralleller med studier om kvinnors arbetsvillkor från andra mansdominerade arbetsorganisationer. Könssegregering, styrning till könsmärkta arbetsuppgifter, broderskapsallianser och minoritets-/synlighetseffekter är teman som ofta återkommer i kvinnornas berättelser. Som en första reflektion under pågående intervjuarbete ser jag att teorier om genusordning kan förklara och tydliggöra såväl kvinnors arbetssituation som deras karriärval. Strukturen och kulturen i byggbranschen talar sitt tydliga språk, det är en mansdominerad arbetsorganisation där kvinnan som civilingenjör är i minoritet och utgör ett annorlunda undantag. Konsekvenserna av dessa erfarenheter kan utgöra förklaringar till kvinnors olika beslut om karriär inom byggbranschen.I pappret kommer jag att presentera en första analys av empirin.Syftet med pappret är att hitta vägar inför den fortsatta forskningen som kan vara fruktbara för att se ytterligare förklaringar och kanske en förändringspotential när det handlar om svårigheterna för kvinnor att vara verksamma som civilingenjörer i den mansdominerade byggbranschen. Jag kommer att beskriva och analysera den bild av arbetsvillkoren (både struktur och kultur) i byggbranschen som kommer fram i intervjuerna. Jag kommer även att beskriva och diskutera motsägelser i kvinnornas berättelser och hur dessa kan tolkas och förstås utifrån ett genusperspektiv. Som stöd och inspiration för detta arbete kommer andra studier om genus och teknik och studier om maskuliniteter att användas.

  • 147.
    Cettner, Annicka
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Overcoming inertia to sustainable stormwater management practice2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In Sweden, there is a growing receptivity for change to more sustainable stormwater practices using green infrastructure approaches. Unlike piped drainage systems they can have multiple benefits in use including flood control, pollutant removal and can add to the quality of urban space supporting green infrastructure through irrigation and providing cooling and an additional water source for supply. However, the change towards non-piped systems is facing many challenges: the tradition of using piped systems; a dominant environmental-technical discourse; lack of legislative, public, political and organisational support and lack of contextual conditions, all of which complicate and hinder the integration of sustainable stormwater management into planning and practice. These challenges, amongst others, are discussed in this thesis which is based on a practical approach and a change perspective. In Sweden as in many other countries, the so far only modest progress towards sustainable stormwater management requires understanding and an explanation as to how better to integrate and implement sustainable stormwater management goals into planning and practice, accelerating the change process. The main research question concerns the possibilities for influencing a shift from traditional management using pipes to one which adopts a more sustainable approach to stormwater management. The study has investigated Swedish municipal officials’ experiences in stormwater planning and practice; focusing on pathways to overcome inertia to the uptake of more sustainable practices. The empirical material is based on two studies: an in-depth interview supplemented with an online questionnaire responded to by 227 from the 290 municipalities in Sweden. Increased knowledge about how to overcome change inertia has been developed by exploring aspects of urban stormwater management: the historical construction of the piped system; the urban stormwater planning process; the concept of sustainable development; a transition approach; receptivity and receptive contexts for action. These linked studies and analyses are presented in five papers. A combination of key theoretical perspectives and methods, combined with relevant stormwater management literature has been used in the interpretation of the empirical findings.The study has identified visions and supportive processes as key change conditions in the contextual situation in which the professionals have to work. Linked to these findings, a comprehensive framework with two complementary receptivity theories focusing collectively on individual or organisational receptivity and receptive contexts for change (action) is proposed. The results from this research show that the sustainable stormwater development process in Sweden continues to emerge slowly and its’ continuing development lies somewhere between increased receptivity and increased innovation in practice. This study has shown that there is no ideal pathway towards change or any particularly strong signs of mainstreaming of sustainable stormwater practice in Sweden. Rather, a variety of alternatives are practiced in various municipalities where the change agenda is neither fixed nor clearly defined. Such flexibility may be useful in order to avoid ‘lock-in’ to fixed paradigms of practice as has happened in the past when urban water systems were originally designed and constructed. A key result from this research is that change implies a constant balancing and rebalancing between committed professional perspectives and an ability to innovate to attain a goal that is expected to be more sustainable. For a continuation of the change processes towards more sustainable stormwater management systems, at a national and international scale, the contextual conditions from where a change has the potential to emerge have to be acknowledged and realized. The best strategy to overcome inertia and support the professionals’ openness and action for change is to identify and create receptive contexts that give possibilities from which sustainable stormwater management practices can emerge.

  • 148.
    Cettner, Annicka
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Women as engineers in construction: a framework for analysis2006Inngår i: Construction in the XXI Century: Local and Global Challenges / [ed] Roberto Pietroforte; Enrico De Angelis; Francesco Polverino, Edizione Scientifiche Italiane SpA , 2006Konferansepaper (Fagfellevurdert)
  • 149.
    Cettner, Annicka
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Ashley, Richard
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Assessing receptivity for change in urban stormwater management and contexts for action2014Inngår i: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 146, s. 29-41, artikkel-id 13Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Individual and organisational receptivity for change towards the use of sustainable stormwater management systems has been previously examined, but the significance of the different contexts for achieving this has been largely unexplored. This paper examines the significance of contexts associated to the actions to bring this about by proposing and evaluating an emerging framework based on two related receptivity theories: the individual or organisational approach and the contextual approach. Results from a Swedish national questionnaire with professionals in stormwater management have been used, together with a limited number of interviews to develop and understand the validity of the framework. The analysis has indicated that the respondents were professionally prepared for change (action) but not practically prepared due to inadequate supportive contexts. In response, a number of potential contexts associated to the necessary actions were identified. The framework was found to provide new insights into the influence of receptive contexts for a change in water management practice. These insights can be used by policy makers and others to better support the realization of professional openness for change and thus accelerate the process of change to sustainable stormwater practice.

  • 150.
    Cettner, Annicka
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Ashley, Richard
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Sustainable development and urban stormwater practice2014Inngår i: Urban Water Journal, ISSN 1573-062X, Vol. 11, nr 3, s. 185-197Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The traditional use of piped systems for stormwater management is increasingly criticized as being ‘unsustainable’. These systems are part of the water domain where much research has focused on sustainable development indicators to support decision-makers in selecting systems that are more sustainable. However, the interest in sustainable development indicators is low. This paper identifies conditions to engage the practitioners to inform their actions in regard to sustainable stormwater management. Empirical evidence has been obtained from interviews with water professionals from Swedish municipalities. The environmental-technical discourse of sustainable stormwater development is a strong barrier in the change process, to the neglect of the social aspects. In the interviews, reframing the discourse was possible in visions of future sustainable stormwater systems embracing green infrastructure. In action, primary conditions can support sustainable pathways in realizing this vision. The paper suggests further incentives for increased implementation of non-structural measures by developing the identified conditions.

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