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  • 1.
    Okwori, Emmanuel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Data integration in asset management of municipal pipe networks in Sweden: Challenges, gaps, and potential drivers2024In: Utilities Policy, ISSN 0957-1787, E-ISSN 1878-4356, Vol. 86, article id 101689Article in journal (Refereed)
    Abstract [en]

    This study involved a survey of Swedish water utilities to evaluate their pipe-network data-collection objectives, usage, storage, and exchange routines. Factors impacting data integration (and the associated benefits) were also identified. Results showed that current data storage and exchange routines can be augmented to support commonly identified objectives and data utilisation needs, especially in larger water utilities. Levels of awareness of the opportunities for and benefits gained through asset management processes and data integration varied between utilities. Further research on the benefits of data integration in pipe network asset management is required to develop an evidence base on benefits accrued in practice, especially considering metadata, the diversity of legacy systems still in operation, costs and policy use.

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  • 2.
    Hedström, Annelie
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Pericault, Youen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Att samordna förnyelse av infrastruktur från strategisk beslutsnivå2023Other (Other academic)
    Abstract [sv]

    Det finns flera nyttor med att samordna förnyelse av VA-ledningar och gator, framförallt när det gäller minskning av kostnader och miljöpåverkan per meter infrastruktur som åtgärdas. Samordningen innebär samtidigt potentiella risker såsom att förkorta livslängden av ledningaroch gator i en för stor omfattning eller att behöva åsidosätta projekt som är nödvändiga för en viss infrastruktur. Ett sätt att arbeta systematiskt med samordning är att införa en strategi som ska följas vid prioritering av förnyelse. De ekonomiska, miljömässiga och sociala effekterna av en sådan strategi kan dock inte uppskattas med nuvarande metoder och verktyg för förnyelseplanering. Därför har en modell för att jämföra samordningsstrategier utvecklats och testats på en fallstudie.

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  • 3.
    Kaykhaii, Saida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Heidfors, Ingemar
    Purac AB, Malmö, Skåne, Sweden.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Enhancing stormwater treatment through ultrafiltration: impact of cleaning chemicals and backwash duration on membrane efficiency2023In: Water Reuse, ISSN 2709-6092, Vol. 13, no 4, p. 634-646Article in journal (Refereed)
    Abstract [en]

    The effect of chemical cleaning and regular backwashing on the efficiency of an ultrafiltration membrane fouled during stormwater treatment was studied. Increasing backwash time from 30 to 60 s resulted in an increase in productivity by 20%. However, the productivity was highest when a backwash time of 45 s was used (3% higher than using 60 s). Chemical cleaning was carried out using an alkaline solution (NaOH with or without NaOCl) followed by acid washing with HCl. The addition of NaOCl to the cleaning chemical did not significantly increase the efficiency of chemical cleaning, and the average pure water permeability increase was 97 ± 13 LMH bar−1 after chemical cleaning with NaOH followed by HCl and 117 ± 15 LMH bar−1 after chemical cleaning with NaOH + NaOCl followed by HCl, on average. In addition, reversibility after chemical cleaning was 96 ± 67%, on average. The result from scanning electron microscopy showed that at the end of the experiments, inorganic foulants existed in both the inner layer (feed side) and the outer layer (permeate side) of the membrane.

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  • 4.
    Söderholm, Kristina
    et al.
    Luleå University of Technology, Department of Social Sciences, Technology and Arts, Social Sciences.
    Vidal, Brenda
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Flexible and Resource-Recovery Sanitation Solutions: What Hindered Their Implementation? A 40-Year Swedish Perspective2023In: The Journal of urban technology, ISSN 1063-0732, E-ISSN 1466-1853, Vol. 30, no 1, p. 23-45Article in journal (Refereed)
    Abstract [en]

    Although Sweden pioneered in the development of resource-recovery sanitation solutions, and there has existed a political awareness of such solutions since the 1990s, their implementation has been slow. We adopt a historical (40-year) perspective and use the main journal of the Swedish sanitation sector as source material to go into depth why this has been the case. Central explanations emerge in terms of previously strong governmental control and continuously tightened environmental requirements that ceaselessly have expanded and strengthened the large-scale centralized sanitation system. In parallel, the sector has continuously been reminded of the shortcomings of alternative (and smaller) solutions and of the tension between recovery and treatment/risk management. The study highlights the possibility of achieving long-term and profound impacts from policy mixes, as well as the strong influence of the sum of challenges and choices over a long time, on today’s perspectives and propensity for change.

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  • 5.
    Sami, Mashreki
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kvarnström, Elisabeth
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    McCarthy, D.T.
    School of Civil and Environmental Engineering, Queensland University of Technology, S Block, Level 7, S727, Brisbane, Qld, Australia.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Greywater treatment in a green wall using different filter materials and hydraulic loading rates2023In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 340, article id 117998Article in journal (Refereed)
    Abstract [en]

    Green walls in urban environments can be both an aesthetic feature and be of practical use in greywater treatment. This study evaluates the effect of different loading rates (4.5 l/d, 9 l/d, and 18 l/d) on the efficiency of treating actual greywater from a city district in a pilot-scale green wall with five different filter materials as substrates (biochar, pumice, hemp fiber, spent coffee grounds (SCG), and composted fiber soil (CFS)). Three cool climate plant species, Carex nigra, Juncus compressus, and Myosotis scorpioides, were chosen for the green wall. The following parameters were evaluated: biological oxygen demand (BOD), fractions of organic carbon, nutrients, indicator bacteria, surfactants, and salt. Three of the five materials investigated – biochar, pumice, and CFS - showed promising treatment efficiencies. The respective overall reduction efficiencies of BOD, total nitrogen (TN) and total phosphorus (TP) were 99%, 75%, and 57% for biochar; 96%, 58%, and 61% for pumice; and 99%, 82% and 85% for CFS. BOD was stable in the biochar filter material with effluent concentrations of 2 mg/l across all investigated loading rates. However, higher loading rates had a significantly negative effect on hemp and pumice for BOD. Interestingly, the highest loading rate (18 l/d) flowing over pumice removed the highest levels of TN (80%) and TP (86%). Biochar was the most effective material in removing indicator bacteria, with a 2.2–4.0 Log10 reduction for E. coli and enterococci. SCG was the least efficient material, giving a higher BOD in the effluent than in the influent. Therefore, this study presents the potential of natural and waste-derived filter materials to treat greywater effectively and the results can contribute to the future development of nature-based greywater treatment and management practices in urban areas.

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  • 6.
    Nyström, Fredrik
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kemisk fällning - en möjlig reningsprocess för dagvatten2023Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Dagvatten från starkt förorenade ytor, såsom motorvägar och större vägkorsningar, leds ofta till dagvattendammar eller andra dagvattensystem. Reningseffekten hos dessa system har ett samband med deras area eftersom de har sedimentering som främsta reningsprocess. Urbaniserade områden bebyggs i dag allt tätare och de tillgängliga ytorna för dagvattenhantering är begränsade. Samtidigt blir miljökraven mer stringenta. Då kan det vara svårt att anlägga system som är dimensionerade för att avskilja föroreningarna tillräckligt effektivt. Flera studier har därför fokuserat på hur effekten hos befintliga system kan förstärkas. I rapporten beskrivs hur väl en reningsprocess med kemisk fällning fungerar på förorenat dagvatten.Kemisk fällning är en välkänd process i vattenverk och avloppsreningsverk där den används för att den är mycket effektiv när det gäller att avskilja både partiklar och fosfor. Många föroreningar i dagvatten förekommer i hög grad som partiklar eller är bundna till partiklar. Därför borde en process med kemisk fällning kunna åstadkomma hög avskiljning även för dagvatten. Men det har inte gjorts särskilt många studier på ämnet, och det har inte genomförts någon bredare undersökning av hur processen fungerar för dagvattenrening. Syftet med projektet var därför att undersöka vilka fällningskemikalier som lämpar sig för dagvatten, vad som bör beaktas i en sådan process och hur bra processen kan bli på att avskilja typiska dagvattenföroreningar. Insamlat dagvatten testades under kontrollerade förhållanden på laboratorium. För att utvärdera processen användes dels en snösmältblandning från en plogbank i Luleå, dels vägdagvatten. Det viktigaste resultatet var att reningsgraden blev mycket hög, över 90 procent, för merparten av metallföroreningar och organiska föroreningar. Reningsgraden hade även låg variation, motsvarande cirka en till fem procentenheter. De fällningskemikalier som presterade bäst var kommersiella förhydrolyserade fällningsprodukter. För att erhålla en kemisk fällning är parametrarna pH och alkalinitet viktiga, och vissa dagvatten kan behöva en pH-justering. Kemisk fällning hade även en tydlig effekt på avskiljning av mindre partiklar (<1μm). Vid enbart sedimentering avskildes inte den fraktionen utan hölls i suspension.Resultaten ska bidra till kunskap om kemisk fällning av dagvatten som kan ge verksamhetsutövare en bredare verktygslåda för effektiv dagvattenrenin

  • 7.
    Pericault, Youen
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Luleå Miljöresurs AB, Murbruksvägen 4, 973 45 Luleå, Sweden.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Modelling the long-term sustainability impacts of coordination policies for urban infrastructure rehabilitation2023In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 236, article id 119912Article in journal (Refereed)
    Abstract [en]

    Due to structural and hydraulic deterioration, urban water pipe networks have annual rehabilitation needs. Worldwide, these needs are often significantly larger than the actual amount of rehabilitation being performed, leading to increased risks of serious failures, lower performance and a growing techno-financial burden for future generations. It is well accepted that, in order to limit the multiple impacts of utility works in the urban environment, rehabilitation projects should be coordinated between water, transport, energy and telecommunication infrastructures. In practice, such coordination means that public utilities must rehabilitate assets earlier or later than technically needed, in order to engage in joint projects in which digging and resurfacing expenditures are shared. Hence, at the municipal scale, such coordination influences two variables that are key to strategic decision support: average costs (€/metre) for asset rehabilitation, and the service lifetimes of those assets. However, current models for strategic asset management do not enable practitioners to estimate how changes in the coordination process may influence the long-term financial and environmental impacts of infrastructure rehabilitation. The present study aimed at addressing this methodological gap by introducing the concept of a coordination window that quantifies to what extent utilities compromise asset rehabilitation times in order to join multi-utility projects. An algorithm for modelling the influence of the coordination window size on long-term sustainability costs is presented and applied to one Swedish municipality. The results suggested that total capital costs and carbon emissions can be lowered by 34% and 16% with a coordination window of 35 and 25 year, in comparison to the no-coordination case.

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  • 8.
    Sami, Mashreki
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kvarnström, Elisabeth
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    On-site greywater treatment systems - influent and effluent quality2023Data set
    Abstract [en]

    The dataset presented here consists of raw data on the quality of influent and effluent greywater from eight on-site greywater treatment systems situated in Södertälje municipality, Sweden. These on-site treatment systems included three types of commercially available package plants and one sand filter. The influent and effluent samples were taken as grab samples between August 2020 and December 2021 and analysed for organic material, nutrients, pathogens, anionic surfactants, salt and (for two of the eight on-site systems) microplastics. Supporting parameters, e.g. suspended solids and pH, are also included. Further, for microplastics, results from blank samples are included.

    This dataset was used to evaluate the treatment efficiency of the on-site greywater treatment systems and to assess the suitability of the treated water for reuse.

  • 9.
    Nyström, Fredrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Polymer-assisted hydraulic dredging for quality control of stormwater pond sediment and reject water – Influence of polymer choice and its preparation2023In: Journal of Water Process Engineering, E-ISSN 2214-7144, Vol. 51, article id 103463Article in journal (Refereed)
    Abstract [en]

    Hydraulic dredging of stormwater ponds may include on-site dewatering of dredged materials using polymersand geotextile filtration. The choice of polymer and its preparation affect the overall operational effectivenessand the quality of the reject water (filtrate) returned to the stormwater pond. This study examined the resultingparticle content as well as nutrient and metal concentrations in the filtrate conducted on hydraulically dredgedstormwater sediment that was chemically conditioned and filtered through geotextile. This study investigateshow polymer choice and preparation affects the outcome. In total, three types of polymers were tested (powder,emulsion commercial cationic polymers and chitosan), the water (tap water or reclaimed) the polymer wasprepared in, and the aging time of the polymer solution. Deviations from manufacturer's instructions on thepolymer preparation increased the amount of polymer needed for an optimal conditioning process. In terms ofpollutant retention, there was no difference between polymer preparations. In the filter cake there was nodiscernable difference between conditioned and unconditioned sediment, rather the difference was noticeable onthe filtrate. Conditioned stormwater sediment produced a geotextile filtrate with considerably less metal andnutrient content than the unconditioned stormwater sediment.

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  • 10.
    Sami, Mashreki
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kvarnström, Elisabeth
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Quality of greywater from a city district before and after treatment in a green wall2023Data set
    Abstract [en]

    The dataset presented here consists of raw data on the quality of influent greywater generated from a city district with 800 PE (population equivalent) and the effluent quality of greywater after treatment using a green wall. Five natural filter materials (pumice, biochar, hemp fiber, spent coffee ground, and composted fiber soil) were used in the green wall and tested for three hydraulic loading rates (54, 108 and 216 l/m2/d). The influent and effluent samples were taken manually between November 2021 and March 2022 and were analyzed for organic material, nutrients, pathogens, anionic surfactants, salt and microplastics. Supporting parameters e.g. suspended solids and pH, are also included in the dataset. Further, for microplastics, results from blank samples are included. This dataset was used to evaluate the treatment efficiency of the filter materials at different hydraulic loading rates.

  • 11.
    Herrmann, Inga
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Vidal, Brenda
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Oulu University, Finland.
    Kinnunen, Juho
    Oulu University, Finland.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Rossi, Pekka
    Oulu University, Finland.
    Ronkanen, Anna-Kaisa
    Oulu University, Finland.
    Heiderscheidt, Elisangela
    Oulu University, Finland.
    Stickprovtagning från små avlopp: Utsläpp, variabilitet och korrelationer av föroreningar2023Report (Other academic)
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  • 12.
    Kaykhaii, Saida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Stormwater treatment using an ultrafiltration membrane and pulsatile fluid flow2023In: Urban Water Journal, ISSN 1573-062X, E-ISSN 1744-9006Article in journal (Refereed)
    Abstract [en]

    A polymeric ultrafiltration (UF) membrane was used for stormwater treatment, with the focus on evaluating the increase in the membrane process productivity by adding pulsatile fluid flow to UF membrane treatment. Sedimentation and sieving were used as pre-treatment. The result showed that increasing the pulse frequency from 0 to 4 Hz increased productivity from -6.6 to 82 LMH. UF membrane removed suspended solids, oil and turbidity below detection limit. The UF membrane also separated total coliforms, E. coli and P. aeruginosa below detection limit. Total organic carbon (TOC) was reduced by between 70 and 91%. In addition, the UF membrane was able to reduce BOD7 and COD to below 7 mg/L in the permeate. According to the US EPA, WHO, and national regulations in Canada,  Japan, and South Korea, treated stormwater can be used for flushing toilets and streets irrigation and agricultural use. 

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  • 13.
    Kaykhaii, Saida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Stormwater treatment with ultrafiltration: Characterisation of backwash water: [Traitement des eaux pluviales par ultrafiltration: Caractérisation deseaux de rétrolavage]2023Conference paper (Other academic)
    Abstract [en]

    Backwash water is an integral part of membrane treatment, normally making up between 2 and 10 % of the clean water production which constitutes a large volume on an industrial scale. To identify suitable treatment or disposal methods for backwash water, it is important to understand the characteristics of the backwash water and what contaminants it contains. In this study, the backwash water from an ultrafiltration membrane process for stormwater treatment was analysed. Concentrations of TSS and TOC were 2.4 and 24 times higher in the backwash water than the influent stormwater. The concentration of particulate and dissolved (<0.45µm) metals in the backwash water was high, for example, the average concentration of total Cu and Cr was 742 ± 215 and 737 ± 243 µg/L. In addition, the average concentration factors for Cu and Cr were 29 ± 9 and 41 ± 15.9. Methods such as coagulation, electrocoagulation and evaporation could be used to further treat backwash water. The residue fraction would contain high concentrations of metals that need to be disposed or could potentially be a good resource for metal recovery in the future.

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  • 14.
    Sagrelius, Pär
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Tyréns AB, Garvaregatan 4C, 602 21, Norrköping, Sweden.
    Blecken, Godecke-Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ashley, Richard
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Department of Civil and Structural Engineering, University of Sheffield, Sheffield, United Kingdom.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Sustainability performance of bioretention systems with various designs2023In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 340, article id 117949Article in journal (Refereed)
    Abstract [en]

    Bioretention systems for urban drainage are one type of blue-green infrastructure that have gained more attention in recent decades. There are numerous design options for these systems, including various construction components, filter material mixtures, and plants. However, the research focus on the impacts of these many design options has mainly been technical, i.e., how different bioretention designs affect runoff pollution treatment and hydraulic control. Knowledge of the effects of various design elements on other sustainability criteria, such as economic, social, and environmental aspects, needs to be developed. This research aimed to evaluate and compare various design elements and bioretention types to gain a better understanding of the relative sustainability of various bioretention systems. This was accomplished by identifying relevant criteria and sub-criteria, covering social, economic, and technical-environmental indicators, in a multicriteria analysis. To evaluate the sustainability performance of various bioretention designs, 12 sub-criteria were allotted −100 to 100 points in a scoring process. The main finding was that while design features had a major impact on bioretention performance, no single design configuration excelled in all criteria. High scores in the social criteria were correlated with the use of trees and smaller volumes of pumice in the filter material mixture. In the economic criteria, extensive use of concrete and a complex mixture of filter material increased the costs. The system with a water-saturated zone and a variety of plant species outperformed the other systems in the technical-environmental criteria. The results can be utilized as a reference to assess design configurations that best satisfy specific needs for each unique bioretention implementation.

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  • 15.
    Milovanovic, Ivan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Müller, Alexandra
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Synthetic stormwater for laboratory testing of filter materials2023In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, Vol. 44, no 11, p. 1600-1612Article in journal (Refereed)
    Abstract [en]

    Synthetic stormwater was tested to determine the ageing effects on dissolved metal concentrations and used in a column experiment to determine efficiency of four different filter materials (milkweed, bark, peat, polypropylene) in removing total and dissolved metals. Synthetic stormwater was created by adding metal salts, oil and collected stormwater sediment to tap water. Two ageing experiments were performed to determine the change of synthetic stormwater quality over time. One experiment lasted for 11 days and another focused on rapid concentration changes one day after preparation. The one-day ageing experiment showed rapid decrease in dissolved concentration of certain metals, specifically Cu. To consider this change, correction coefficients for each metal were developed and used to estimate the average dissolved metal concentration in the synthetic stormwater during the experiment to determine filter treatment efficiency. During the 11-day experiment on metal concentrations, no noticeable quality changes were observed for at least six days after the preparation of synthetic stormwater. Furthermore, a column experiment was run with duplicate filter columns. Inflow and outflow samples were analysed for total and dissolved metals, turbidity, particle size distribution, and pH. High removal of total metal concentrations was noticed in all tested filter media (58-94%). Dissolved metal concentration removal varied among different filter media. In general, columns with bark and peat media were able to treat dissolved metals better than polypropylene and milkweed. The level of treatment of dissolved metals between the different filter media columns were bark > peat > milkweed > polypropylene.

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  • 16.
    Vidal, Brenda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kinnunen, Juho
    Water, Energy and Environmental Engineering Research Facility, Faculty of Technology, 90014 University of Oulu, Finland.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Heiderscheidt, Elisangela
    Water, Energy and Environmental Engineering Research Facility, Faculty of Technology, 90014 University of Oulu, Finland.
    Rossi, Pekka
    Water, Energy and Environmental Engineering Research Facility, Faculty of Technology, 90014 University of Oulu, Finland.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Treatment efficiency of package plants for on-site wastewater treatment in cold climates2023In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 342, article id 118214Article in journal (Refereed)
    Abstract [en]

    Package plants (PP) are implemented around the world to provide on-site sanitation in areas not connected to a sewage network. The efficiency of PP has not been comprehensively studied at full scale, and the limited number of available studies have shown that their performance varies greatly. Their performance under cold climate conditions and the occurrence of micropollutants in PP effluents have not been sufficiently explored. PP are exposed to environmental factors such as low temperature, especially in cold regions with low winter temperatures and deep frost penetration, that can adversely influence the biochemical processes. The aim of this study was to investigate the treatment efficiency and possible effects of cold temperatures on PP performance, with focus on traditional contaminants (organics, solids, nutrients and indicator bacteria) and an additional assessment of micropollutants on two PP. Eleven PP hosting different treatment processes were monitored. Removal of biological oxygen demand (BOD) was high in all plants (>91%). Six out of the 11 PP provided good phosphorus removal (>71%). Small degrees of nitrification were observed in almost all the facilities, despite the low temperatures, while denitrification was only observed in two plants which achieved the highest nitrification rates (>51%) and had sludge recirculation. No strong correlation between wastewater temperature and BOD, nutrients and indicator bacteria concentration in the effluents was found. The high data variability and the effects of other process parameters as well as snow-melt water infiltration are suggested as possible reasons for the lack of correlation. However, weak negative relations between effluent concentrations and wastewater temperatures were detected in specific plants, indicating that temperature does have effects. When managed adequately, package plants can provide high BOD and phosphorus removal, but nitrogen and bacteria removal remain challenging, especially at low temperatures. Pharmaceutical compounds were detected in the effluents at concentrations within or above ranges reported for large treatment plants while phthalate ester concentrations were below commonly reported effluent concentrations.

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  • 17.
    Vidal, Brenda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Utvärdering av drifts- och underhållsinstruktioner för markbaserade avloppsprodukter: En analys av nuvarande praxis och möjliga förändringar2023Report (Other academic)
    Abstract [sv]

    Alla avloppslösningar kräver skötsel och underhåll för att fungera ändamålsenligt under hela sin livslängd. Underhållsbehovet varierar beroende på storlek, typ och reningsgrad. I Havs- och vattenmyndighetens vägledning om prövning av små avlopp finns ett avsnitt om drift- och underhållsinstruktion samt ett översiktligt informationsblad. Redan i tillståndsansökan bör sökanden redovisa anläggningens behov av underhåll, kontroll och service i en så kallad drift- och underhållsinstruktion. Instruktionen bör innehålla både den egenkontroll som verksamhetsutövaren själv avser utföra och den eventuella kontroll som behöver utföras av sakkunnig. Instruktionen måste sammanfattningsvis innehålla nödvändiga uppgifter för att säkerställa anläggningens funktion i drift.

    Tidigare studier om uppföljande besök på prefabricerade markbädd visade att det finns brist på tydliga skötselinstruktioner till fastighetsägaren och brist på insikt om skötselansvar hos fastighetsägarna. 

    Syftet med detta projekt var att undersöka i vilken utsträckning det finns drifts- och underhållsinstruktioner som motsvarar HaV:s nuvarande vägledning för markbaserade avloppsprodukter på marknaden, samt att i dialog med branschen utvärdera om det finns anledning att göra förändring i vägledning, i drift- och underhållsinstruktioner för markbaserade avloppsprodukter på marknaden och/eller i fysisk utformning av anläggningarna.

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  • 18.
    Vidal, Brenda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kinnunen, Juho
    University of Oulu, Finland.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Heiderscheidt, Elisangela
    University of Oulu, Finland.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Wastewater influent and effluent concentrations from on-site package plants in Northern Sweden and Finland2023Data set
    Abstract [en]

    The data contains influent and effluent concentrations of traditional parameters measured in on-site package plants for domestic wastewater treatment serving single houses or small communities (2-30 person equivalent). The parameters analysed include organic matter, suspended solids, nutrients (phosphorus and nitrogen compounds) and indicator bacteria, as well as other physicochemical parameters such as temperature, pH and turbidity, and chloride as a tracer compound to detect dilution effects. Additional influent and effluent concentrations of micropollutants from two slightly larger plants (serving 12-30 person equivalent) are also included. These micropollutants consisted of 19 selected pharmaceuticals, caffeine and the sweetener Acesulfame K, and 15 phthalates.The purpose of the collected dataset was to investigate the treatment efficiency of package plants operating in cold climate conditions throughout different seasons. The samples were collected in the northern regions of Sweden (Norrbotten) and Finland (North Ostrobothnia and Lapland) characterised by low winter temperatures and deep frost penetration.The data has not been processed and consists of results (raw data) obtained directly from our university laboratory in Luleå university of technology (nutrient samples) and accredited laboratories (traditional parameters, microbiology, micropollutants).

  • 19.
    Öhrn Sagrelius, Pär
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Tyréns AB, Garvaregatan 4C, 602 21, Norrköping, Sweden.
    Blecken, Godecke
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ashley, Richard
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Department of Civil and Structural Engineering, University of Sheffield, Sheffield, United Kingdom.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Environmental impacts of stormwater bioretention systems with various design and construction components2022In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 359, article id 132091Article in journal (Refereed)
    Abstract [en]

    Nature-based blue-green infrastructure for urban stormwater management, such as bioretention systems, is considered to provide multiple benefits compared with conventional stormwater runoff quantity and quality control. There are a range of bioretention systems and design and construction can vary widely. Studies comparing environmental impacts between different stormwater bioretention systems with various design elements and construction components have been lacking and hence, this study aims to address this gap. Various designs of stormwater bioretention systems with differing construction components and filter media mixtures have for the first time been compared using a life cycle assessment approach. Environmental impacts related to the production, transportation, and installation phases (i.e. before operation) of four types of bioretention systems, encompassing 11 configurations, have been assessed. The various construction components and filter media mixtures used incur differing degrees of environmental impacts. The filter media mixtures requiring longer transportation distances were associated with the highest environmental impacts. In this analysis, the bioretention systems built with more kerb stone, without geotextile and a filter media with sand, soil and gravel incurred the lowest environmental impacts. Whereas the bioretention systems constructed with the most concrete and with filter media that included pumice incurred the highest environmental impacts in all categories, up to 9–24 times greater than the systems with less concrete and no pumice. When means of transportation and distances were considered further in the sensitivity analysis, the concrete intensive structures incurred the highest environmental impacts. These findings can improve design choices and selection of construction components for stormwater bioretention systems where environmental impacts are considered important.

  • 20.
    Hedström, Annelie
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ahlström, Marcus
    RISE.
    Johannesdottir, Solveig
    RISE.
    Flodin, Elin
    RISE.
    Hübinette, Maria
    RISE.
    Erfarenheter av LTA-system2022Report (Other academic)
    Abstract [sv]

    Hur ser va-branschens erfarenheter av lättryckavloppsystemut? I rapporten presenteras utmaningar och framgångsfaktorerkopplade till dessa LTA-system. Om systemen anläggsoch används på rätt sätt kan de vara ett bra alternativ tillkonventionella självfallssystem, men frågor kring svavelväteoch livscykelkostnader behöver redas ut för att säkerställasystemens långsiktiga hållbarhet.Lättryckavloppssystem (LTA-system) används ofta som alternativ till självfallssystemi omvandlingsområden och där va-huvudmännens verksamhetsområden utvidgas.Under de senaste 20 åren har användningen av LTA-system ökat kraftigt, och i dag ärutbyggnadstakten mycket stor i vissa delar av landet. LTA-system är enklare att anläggai områden med utmanande topografi och markförhållanden, och ledningsgravarnakan göras relativt grunda så att schaktningsbehovet blir mindre än för konventionellasjälvfallsledningar.Genom bättre förståelse för LTA-system finns det stora möjligheter för det svenskava-kollektivet att minska sina investerings- och driftkostnader vid utvidgning av verksamhetsområden, sannolikt med hundratals miljoner kronor de närmaste 20 åren dåbranschen står inför stora investeringar. För att möjliggöra besparingarna behövs deten tydlig helhetsbild av LTA-system och av alla de erfarenheter och den kunskap somfinns. Vilka är framgångsfaktorerna för att lyckas med LTA-system och vad bör mansom va-huvudman akta sig för?Många va-huvudmän har lång erfarenhet av att förvalta LTA-system, medan andraupplever att de behöver mer och bättre underlag innan de kan känna sig trygga attanlägga och förvalta en ny typ av system. Projektet har sammanställt de erfarenhetersom va-huvudmän har av LTA-system. Man har gått igenom litteratur och juridisk praxiskring LTA-system i Sverige, samt genomfört en workshop, en enkät och intervjuer föratt inhämta branschens erfarenheter av LTA i planerings-, bygg- och driftskedena. Vilkautmaningar ser branschen med systemen och var finns det kunskapsluckor? Underprojektets genomförande visade det sig att va-huvudmännen har mycket att lära avvarandra och att erfarenhetsutbyte är viktigt.Resultaten visar att det är viktigt med god planering och anpassning till lokala förhållanden för att lyckas med LTA. Svavelvätebildning är en stor och svårhanterlig fråga.Problemen uppkommer delvis på grund av att det är svårt att planera och dimensionerakorrekt. Ansvarsfrågorna regleras visserligen i lagstiftning men upplevs ändå som svårnavigerade. Det beror på att vissa delar av LTA-systemet är brukarens ansvar och andradelar är va-huvudmannens. Goda relationer mellan fastighetsägare och va-huvudmänär en framgångsfaktor för att säkerställa god funktion hos systemen över tid eftersomLTA ställer högre krav på brukaren än självfallssystemen gör.Frågor som behöver hanteras i fortsättningen är bland annat svavelvätebildning ochsystemens långsiktiga kostnader. Svavelväte är ett stort problem, och samma lösningför att minska svavelväte ger olika resultat på olika platser. Branschen behöver merkunskap och riktlinjer för hur man bäst undviker och avhjälper problemen. De långsiktiga kostnaderna för LTA är oklara och svåra att uppskatta korrekt och planera för. Desamlade livscykelkostnaderna för anläggning, drift och underhåll saknas, och underlagbehöver sammanställas för att man ska kunna ta bättre beslut och skapa mer effektivadriftorganisationer.

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  • 21.
    Isaksson, Frida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Lundy, Lian
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Székely, Anna J.
    Department of Aquatic Science and Assessment, Swedish University of Agricultural Science, 750 07 Uppsala, Sweden.
    Mohamed, Nahla
    Department of Aquatic Science and Assessment, Swedish University of Agricultural Science, 750 07 Uppsala, Sweden.
    Evaluating the Use of Alternative Normalization Approaches on SARS-CoV-2 Concentrations in Wastewater: Experiences from Two Catchments in Northern Sweden2022In: Environments, E-ISSN 2076-3298, Vol. 9, no 3, article id 39Article in journal (Refereed)
    Abstract [en]

    The detection of SARS-CoV-2 RNA fragments in feces has paved the way for wastewater-based epidemiology to contribute to COVID-19 mitigation measures, with its use in a public health context still under development. As a way to facilitate data comparison, this paper explores the impact of using alternative normalization approaches (wastewater treatment plant (WWTP) flow, population size estimates (derived using total nitrogen (TN), total phosphorus (TP) and census data) and pepper mild mottle virus (PMMoV)) on the relationship between viral wastewater data and clinical case numbers. Influent wastewater samples were collected at two WWTPs in Luleå, northern Sweden, between January and March 2021. TN and TP were determined upon sample collection, with RNA analysis undertaken on samples after one freeze–thaw cycle. The strength of the correlation between normalization approaches and clinical cases differed between WWTPs (r ≤ 0.73 or r ≥ 0.78 at the larger WWTP and r ≤ 0.23 or r ≥ 0.43 at the smaller WWTP), indicating that the use of wastewater as an epidemiological tool is context-dependent. Depending on the normalization approach utilized, time-shifted analyses imply that wastewater data on SARS-CoV-2 RNA pre-dated a rise in clinical cases by 0–2 and 5–8 days, for the lager and smaller WWTPs, respectively. SARS-CoV-2 viral loads normalized to the population or PMMoV better reflect the number of clinical cases when comparing wastewater data between sewer catchments.

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  • 22.
    Panasiuk, Oleksandr
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Langeveld, Jeroen
    Department of Water Management, TU Delft, AA Delft 2600, The Netherlands; Partners4UrbanWater, MJ Nijmegen 6524, The Netherlands.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Identifying sources of infiltration and inflow in sanitary sewers in a northern community: comparative assessment of selected methods2022In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 86, no 1, p. 1-16Article in journal (Refereed)
    Abstract [en]

    Infiltration and inflow (I/I) into sanitary sewers causes numerous negative effects on the whole wastewater management system and ultimately, on the receiving waters. Consequently, a number of methods have been developed to analyse the performance of sewer systems with respect to I/I, including: distributed temperature sensing (DTS), closed-circuit television (CCTV) inspections, flow and conductivity measurements, automatic or grab sampling of ammonium, smoke testing, and visual inspection of manholes. Such methods were compared in an application to sanitary sewers in a small community and assessed with respect to their accuracy and ability to identify locations of sources of I/I, as well as temporal and spatial resolutions of the obtained results. Furthermore, different approaches to ammonium sampling during I/I monitoring campaigns were discussed. It was concluded that among the methods tested in this study, DTS had the highest temporal and spatial resolutions, while ammonium grab sampling showed promise for initial screening of large catchments.

  • 23.
    Milovanovic, Ivan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Performance of a Zeolite Filter treating Copper Roof Runoff2022In: Urban Water Journal, ISSN 1573-062X, E-ISSN 1744-9006, Vol. 19, no 5, p. 499-508Article in journal (Refereed)
    Abstract [en]

    Copper is a common roofing material used in urban environments, yet it poses a threat to the ecosystem. Space requirements for stormwater treatment in urban areas are often problematic. This study investigated the treatment efficiency of a filter system containing zeolite as filter medium and treatment of copper roof runoff in field conditions. Emphasis was placed on copper and zinc treatment, while the release of sodium and aluminium was also evaluated. The filter system was monitored over a period of 16 months (7 sampling events). The filter reduced the total and dissolved copper by 52–82% and 48–85%, respectively. Although the average observed treatment efficiency of copper and zinc was high, considerable decline in filter efficiency was noticed, indicating potential saturation of the filter medium. Moreover, the copper concentrations in the outlet were still high, 350–600 μg/l, and significantly higher than the concentrations recommended by the relevant authorities.

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  • 24.
    Sami, Mashreki
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Österlund, Helene
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kvarnström, Elisabeth
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Removal of Microplastics from Greywater Using a Green Wall Treatment System2022In: 17th International Conference on Wetland Systems for Water Pollution Control: Conference Proceedings, 2022, p. 505-508Conference paper (Refereed)
    Abstract [en]

    A green wall with four filter media - pumice, biochar, hemp, and compost soil - was investigated with regard to the removal of microplastics from real greywater. Nine polymers were analysed using thermal extraction desorption gas chromatography-mass spectrometry (TED-GC/MS). The results showed the presence of polyvinylchloride (PVC), polystyrene (PS), poly-ethylene-terephthalate (PET), polypropylene (PP), and polyamide (PA) in the influents and effluents. High concentration of PS (22 μg/l) and PET (73 μg/l) were observed in the influent but were removed efficiently in the green wall with effluent concentrations of <2 μg/l from all filter materials except for hemp. The effluent from one hemp replicate showed higher concentrations of PVC (58 μg/l) and PET (114 μg/l) than the influent. During the sampling period, all filter materials removed TSS, BOD and TOC by >90%.

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  • 25.
    Kaykhaii, Saida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Stormwater treatment using ultrafiltration – Effect of cleaning chemical and backwash time on membrane efficiency2022Conference paper (Refereed)
    Abstract [en]

    Stormwater runoff is known as one of the main contributors of pollutants which is often discharged untreated to the water bodies and causes environmental risk [1]. Membrane treatment may be a good option for treatment of heavily polluted stormwater as it can also remove small particles and colloids that are not normally captured in typical stormwater facilities such as ponds, wetlands, etc. However, fouling in membranes is challenging to control. Application of a pre-treatment prior to the membrane process might help to postpone fouling [2]. In addition, a proper combination of backwash and chemical cleaning for the membrane is essential but this has not yet been studied specifically for stormwater runoff treatment with membranes. In this study, a combination of ultrafiltration PVP/PES membrane with pulsatile fluid flow was used for separation of pollutants from stormwater. Sieving was considered as pre-treatment. In addition, a combination of backwash and chemical cleaning was used to assess reversibility, flux recovery and productivity of the membrane. The results showed that by increasing backwash time from 30 to 60 s, the reversibility and flux recovery increased from 26% to 75% and 55% to 87%, on average and also resulted in 20% increase in productivity. Cleaning chemically with alkaline solution (NaOH, pH=12), followed by acidic solution (HCl, pH=2), had a good impact on removing foulants from membrane surface. According to the experiments, addition of NaOCl to the alkaline solution did not have significant effect on pure water flux recovery. From environmental point of view, using NaOCl is not recommended [3].

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  • 26.
    Klapp, Rasmus
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Molle, P.
    INRAE, REVERSAAL, Villeurbanne, F-69100, France.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    The French two-stage vertical flow constructed wetland in subarctic climate2022In: 17th International Conference on Wetland Systems for Water Pollution Control: Conference Proceedings, IWA Publishing, 2022, p. 579-580Conference paper (Refereed)
    Abstract [en]

    Conventional small wastewater treatment plants in Sweden produce a sludge that needs to be collected and transported long distances to a centralised treatment facility. As many of these small plants are old and need replacement, the question arises weather a more sustainable solution is possible. The French two-stage vertical flow constructed wetland (VFCW) is a method where very little sludge handling is required, as the sludge is treated on-site. Therefore, this study aims to investigate cold climate performance of such a system in northern Sweden. A pilot-scale VFCW was built and sampled for BOD, nutrients and microplastics since November 2021. Results indicate that treatment performance is adequate and that microplastic can also be treated.

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  • 27.
    Okwori, Emmanuel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Using centrality measures, network cross k-function and geographically weighted regression as decision support for operational issues and redesigning sewers.2022In: 10th International Conference on Sewer Processes and Networks, 2022Conference paper (Refereed)
    Abstract [en]

    The topology of Sanitary Sewer Networks (SSNs) can play an influential role in the occurrence and magnitude of operational failures such as blockages and basements flooding (Reyes-Silva et al., 2020). For example, meshed (grid-like) topologies are reported to be less vulnerable to failures compared to branched (tree-like) topologies (Zhang et al., 2017). However, in reality, most SSNs are reported to have a predominantly branched topology (Reyes-Silva et al., 2020). Therefore, it could be argued that the spatial behaviour of operational failures may be related to the topological properties of SSNs. This study explored this argument by investigating the spatial association between the location of recurrent blockages and the location of influential nodes within the network. Graph theory–centrality measures (Ganesan et al., 2020) and the network cross-K-function (Okabe and Sugihara, 2012) were the methods used. Secondly, the question of which structural, hydraulic or environmental factors may explain the identified spatial associations was also explored using geographically weighted regression (Fotheringham and Charlton, 2009). In lieu of robust properly calibrated hydraulic models, results from centrality measures and network cross k-function can support the discovery of influential locations within the topology of SSNs that may propagate recurrent blockages. Such influential locations may also be inception points for remedial actions such as redesigning, which may be more cost-effective in the long term compared to conventional approaches like flushing. Results from a preliminary application of centrality measures and network cross-function to the SSN of one municipality (total network length 500 km, ≈40 people/km) using its historical blockage data are presented.

  • 28.
    Kaykhaii, Saida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Applicability of using sedimentation and membrane filtration for stormwater treatment2021Conference paper (Refereed)
    Abstract [en]

    Stormwater runoff is one of the most important contributor of pollutants to natural waters. Therefore, separation of pollutants from stormwater runoff before entering the receiving waters is an important issue. Nitrogen (ammonium, nitrite, nitrate, total nitrogen), phosphorus (organic and inorganic), metals (Fe, Cd, Zn, Pb, As, Al, metalloid arsenic, Cr, Cu, Ni in total, dissolved and truly dissolved form) are main compounds that are contained in various concentrations in the runoff and should be separated. Various methods have been used for stormwater treatment. Membrane technology has shown acceptable treatment ability in water and wastewater industries1, but is not yet used for treatment of stormwater. Ceramic, polymeric and metallic membranes have been used in other research studies in order to optimise removal efficiency for separation of particulate, colloidal and dissolved substances in runoff. To prevent fouling, which is the major problem in membranes and to decrease the operational cost, use of a proper pre-treatment is helpful 2–4, as is periodical cleaning of membrane surface 5,6. This process can be further assisted by using membranes with larger pore size (microfiltration, ultrafiltration) than nanofiltration and reverse osmosis membranes which have smaller pore size but higher removal efficiency. In this study, sedimentation was used as a pre-treatment method and a membrane process with different pore sizes and pulsatile flow (fluid flow with periodical variation) were evaluated with respect to separation of pollutants from a snowmelt mixture. For the aim of this research work, polyether sulfone nanofiltration and ultrafiltration membranes (PES NF, UF membrane) were used to assess the ability of the overall process to postpone fouling and treat the snowmelt mixture. The variation of pulse frequency was chosen between 0 and 2 Hz. A peristaltic pump with a constant rotational velocity of 220 rpm was used in all the experiments. Sedimentation as pre-treatment method was investigated in pre-experiments and it was shown that a variation in sedimentation time between 0.5-1 hours did not affect the treatment ability of the process. Therefore, 0.5 hour of sedimentation time was chosen in order to reduce the experimental run time. The experimental runs will be carried out during the winter period Feb-April 2021. The concentration of TSS, pH, total and dissolved metals and chloride, as well as the particle size distribution, turbidity and volume of clean water achieved in each experimental run is measured. The results from these experiments will give valuable information about treatment efficiency, if pulsatile flow increases the treatment performance as well as knowledge about the clogging process of the filter.

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  • 29.
    Okwori, Emmanuel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Pericault, Youen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ugarelli, Rita
    SINTEF Community, SINTEF AS, 0373 Oslo, Norway.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Data-driven asset management in urban water pipe networks: a proposed conceptual framework2021In: Journal of Hydroinformatics, ISSN 1464-7141, E-ISSN 1465-1734, Vol. 23, no 5, p. 1014-1029Article in journal (Refereed)
    Abstract [en]

    Analytical tools used in infrastructure asset management of urban water pipe networks are reliant on asset data. Traditionally, data required by analytical tools has not been collected by most water utilities because it has not been needed. The data that is collected might be characterised by low availability, integrity and consistency. A process is required to support water utilities in assessing the accuracy and completeness of their current data management approach and defining improvement pathways in relation to their objectives. This study proposes a framework to enable increased data-driven asset management in pipe networks. The theoretical basis of the framework was a literature review of data management for pipe network asset management and its link to the coherence of set objectives. A survey to identify the current state of data management practice and challenges of asset management implementation in five Swedish water utilities and three focus group workshops with the same utilities was carried out. The main findings of this research were that the quality of pipe network datasets and lack of interoperability between asset management tools was a driver for creating data silos between asset management levels, which may hinder the implementation of data-driven asset management. Furthermore, these findings formed the basis for the proposed conceptual framework. The suggested framework aims to support the selection, development and adoption of improvement pathways to enable increased data-driven asset management in municipal pipe networks. Results from a preliminary application of the proposed framework are also presented.

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  • 30.
    Sagrelius, Pär
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Tyréns AB, Stockholm, Sweden.
    Blecken, Godecke-Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ashley, Richard
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water. Department of Civil and Structural Engineering, University of Sheffield, Sheffield, United Kingdom.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Environmental impacts of stormwater bioretention systems with various construction components2021In: 15th International Conference on Urban Drainage 2021 Delegates Handbook / [ed] David McCarthy, 2021, p. 710-712, article id 225Conference paper (Other academic)
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  • 31.
    Lundy, Lian
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Making Waves: Collaboration in the time of SARS-CoV-2 - rapid development of an international co-operation and wastewater surveillance database to support public health decision-making2021In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 199, article id 117167Article in journal (Refereed)
    Abstract [en]

    The presence of SARS-CoV-2 RNA in wastewater was first reported in March 2020. Over the subsequent months, the potential for wastewater surveillance to contribute to COVID-19 mitigation programmes has been the focus of intense national and international research activities, gaining the attention of policy makers and the public. As a new application of an established methodology, focused collaboration between public health practitioners and wastewater researchers is essential to developing a common understanding on how, when and where the outputs of this non-invasive community-level approach can deliver actionable outcomes for public health authorities. Within this context, the NORMAN SCORE “SARS-CoV-2 in sewage” database provides a platform for rapid, open access data sharing, validated by the uploading of 276 data sets from nine countries to-date. Through offering direct access to underpinning meta-data sets (and describing its use in data interpretation), the NORMAN SCORE database is a resource for the development of recommendations on minimum data requirements for wastewater pathogen surveillance. It is also a tool to engage public health practitioners in discussions on use of the approach, providing an opportunity to build mutual understanding of the demand and supply for data and facilitate the translation of this promising research application into public health practice.

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  • 32.
    Herrmann, Inga
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marklund, Stefan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Englund, Maja
    RISE.
    Ljung, Emelie
    RISE.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Markbaserad rening - design, funktion och bedömningkriterier vid tillsyn2021Report (Other academic)
    Abstract [sv]

    Markbaserade reningsanläggningar för avloppsvatten har använts länge i Sverige och anses som en robust och driftsäker reningsmetod. Kommunerna som ansvarar för tillsynen har vid inspektionsbesök av anläggningar observerat olika brister i sådana markbaserade anläggningar, t.ex. förhöjd slamförekomst i slamavskiljare, fördelningsbrunn, spridarledningar och/eller luftningsrör, för höga vattennivåer i delar av anläggningen och/eller problem med ventilation. Dessa problem har också uppmärksammats i olika projekt. Det är dock generellt svårt att bedöma huruvida dessa brister har en negativ påverkan på reningsanläggningens funktion. Det finns ett behov av ökad kunskap om när en markbaserad anläggning fungerar eller inte och hur detta ska bedömas, både för att en anläggning inte ska dömas ut i onödan och för att en anläggning som inte fungerar tillfredsställande får rätt typ av åtgärd.

    I detta projekt undersöktes design-, funktions- och tillsynsprinciper för markbaserade anläggningar med hjälp av litteraturstudier och intervjuer. Syftet var att bidra till utformning av relevanta bedömningskriterier för markbaserade reningsanläggningar som kan användas vid prövning och tillsyn. Målen var att:

    - granska litteraturen inom markbaserad rening för att lista viktiga faktorer som påverkar funktionen,

    - jämföra svenska dimensioneringskriterier för slamavskiljare och infiltrationer med kriterier som används i andra länder (Norge och USA),

    - beskriva hur tillsyn av markbaserade anläggningar genomförs hos kommuner som är aktiva inom tillsyn,

    - belysa hur olika kommuner resonerar angående bedömningen av olika typer av brister (i detta mål ingår att bedöma hur allvarliga olika typer av brister är – det vill säga om bristerna kräver en uppföljning i form av föreläggande eller förbud eller om det räcker med information eller enklare uppföljning – och hur pass stor samstämmighet som finns mellan olika kommuner vid bedömning av bristers allvarlighet),

    - uppmärksamma svårigheter med att bedöma funktionen i markbaserade anläggningar och peka ut framtida områden som behöver vidare arbete, samt att

    - sammanfatta hur tillsyn bedrivs i andra länder och resonera kring vilka lärdomar som kan dras därur.

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  • 33.
    Sami, Mashreki
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Wu, Jiechen
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kvarnström, Elisabeth
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Pollutant Removal In On-Site Greywater Treatment Systems2021Conference paper (Refereed)
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  • 34.
    Okwori, Emmanuel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Spatial heterogeneity assessment of factors affecting sewer pipe blockages and predictions2021In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 194, article id 116934Article in journal (Refereed)
    Abstract [en]

    Efficient management of sewer blockages requires increased preventive maintenance planning. Conventional approaches to the management of blockages in sewer pipe networks constitute largely unplanned maintenance stemming from a lack of adequate information and diagnosis of blockage causative mechanisms. This study mainly investigated a spatial statistical approach to determine the influence of explanatory factors on increased blockage propensity in sewers based on spatial heterogeneity. The approach consisted of the network K-function analysis, which provided an understanding of the significance of the spatial variation of blockages. A geographically-weighted Poisson regression then showed the degree of influence that explanatory factors had on increased blockage propensity in differentiated segments of the sewer pipe network. Lastly, blockage recurrence predictions were carried out with Random Forest ensembles. This approach was applied to three municipalities. Explanatory factors such as material type, number of service connections, self-cleaning velocity, sagging pipes, root intrusion risk, closed-circuit television inspection grade and distance to restaurants showed significant spatial heterogeneity and varying impacts on blockage propensity. The Random Forest ensemble predicted blockage recurrence with 60–80% accuracy for data from two municipalities and below 50% for the last. This approach provides knowledge that supports proactive maintenance planning in the management of blockages in sewer pipe networks.

  • 35.
    Herrmann, Inga
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Okwori, Emmanuel
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Marklund, Stefan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Spillvattenflöden från hushåll med enskilt avlopp och kompakt reningsteknik2021Report (Other academic)
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  • 36.
    Kaykhaii, Saida
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Stormwater treatment using membrane filtration with pulsatile fluid flow2021Conference paper (Refereed)
    Abstract [en]

    Stormwater runoff is one of the most important contributor of pollutants to natural waters. Therefore, separation of pollutants from stormwater runoff before entering the receiving waters is an important issue. Nitrogen (ammonium, nitrite, nitrate, total nitrogen), phosphorus (organic and inorganic), metals (Fe, Cd, Zn, Pb, As, Al, metalloid As, Cr, Cu, Ni in total, dissolved and truly dissolved form) are main compounds that are contained in various concentrations in the runoff and should be separated. Various methods have been used for stormwater treatment. Membrane technology is applied in water and wastewater industries1, but is not yet used for treatment of stormwater. Ceramic, polymeric and metallic membranes have been used in other research studies in order to optimise removal efficiency for separation of particulate, colloidal and dissolved substances in runoff. To prevent fouling, which is the major problem in membranes and to decrease the operational cost, use of a proper pre-treatment is helpful 2–4, as is periodical cleaning of the membrane surface 5,6. This process can be further assisted by using membranes with larger pore size (microfiltration, ultrafiltration) than nanofiltration and reverse osmosis membranes which have smaller pore size but higher removal efficiency. In this study, sedimentation was used as a pre-treatment method and an ultrafiltration membrane process and pulsatile flow were evaluated with respect to separation of pollutants from snowmelt mixture. A bench-scale membrane unit was used with a polyether sulfone ultrafiltration membrane (PES/PVP UF membrane) to assess the efficiency of the process and to evaluate if pulsatile flow at different pulse frequencies (0 and 4 Hz) can postpone fouling. The feed and permeate was sampled and analysed on the concentration of TSS, pH, total and dissolved metals and chloride content, as well as the particle size distribution, TOC, turbidity and oil index. The volume of permeate achieved in each experimental run was monitored. The results from these experiments showed that by increasing pulse frequency from 0 to 4 Hz, the productivity of membrane increased from 13.5% to 65.5%. In addition, TOC removal increased from 70% to 87%. Regardless of pulse frequency the ultrafiltration membrane set-up removed TSS, particles and oil fractions completely. Dissolved As, Cd, Cu, Cr, Ni, Pb and P were reduced by 16, 12.6, 11.8, 23.5, 21, 44 and 73.1%, respectively.

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  • 37.
    Vidal, Brenda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kinnunen, Juho
    University of Oulu, Water, Energy and Environmental Engineering Research Unit.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Heiderscheidt, Elisangela
    University of Oulu, Water, Energy and Environmental Engineering Research Unit.
    Rossi, Pekka
    University of Oulu, Water, Energy and Environmental Engineering Research Unit.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Treatment efficiency of small-scale package plants in northern Sweden and Finland2021Conference paper (Refereed)
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  • 38.
    Milovanovic, Ivan
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Vojtěch, Bares
    Czech Technical University, Prague, Czech Republic.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Picek, Tomas
    Czech Technical University, Prague, Czech Republic.
    Marsalek, Jiri
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Enhancing stormwater sediment settling at detention pond inlets by a bottom grid structure (BGS)2020In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 81, no 2, p. 274-282Article in journal (Refereed)
    Abstract [en]

    Stormwater sediments of various sizes and densities are recognised as one of the most important stormwater quality parameters that can be conventionally controlled by settling in detention ponds. The bottom grid structure (BGS) is an innovative concept proposed in this study to enhance removal of stormwater sediments entering ponds and reduce sediment resuspension. This concept was studied in a hydraulic scale model with the objective of elucidating the effects of the BGS geometry on stormwater sediment trapping. Towards this end, the BGS cell size and depth, and the cell cross-wall angle were varied for a range of flow rates, and the sediment trapping efficiency was measured in the model. The main value of the observed sediment trapping efficiencies, in the range from 13 to 55%, was a comparative assessment of various BGS designs. In general, larger cells (footprint 10 × 10 cm) were more effective than the smaller cells (5 × 5 cm), the cell depth exerted small influence on sediment trapping, and the cells with inclined cross-walls proved more effective in sediment trapping than the vertical cross-walls. However, the BGS with inclined cross-walls would be harder to maintain. Future studies should address an optimal cell design and testing in an actual stormwater pond.

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  • 39.
    Nyström, Fredrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Laboratory scale evaluation of coagulants for treatment of stormwater2020In: Journal of Water Process Engineering, E-ISSN 2214-7144, Vol. 36, article id 101271Article in journal (Refereed)
    Abstract [en]

    The treatment effect and process characteristics of coagulation were investigated in semi-synthetic stormwater in laboratory-scale using jar tests. An initial screening of twelve coagulants and flocculant aids was carried out to find a selection of chemicals that efficiently reduced turbidity and suspended solids. Five coagulants were then further investigated with additional parameters measured (conductivity, alkalinity, and ζ-potential). The semi-synthetic stormwater was characterized by a high but variable, particle content, and low alkalinity. In the jar tests, a high treatment efficiency (>90 % reduction of both turbidity and suspended solids) was achieved for all coagulants. For very low alkalinity waters, the use of a biopolymer such as chitosan may be advantageous due to minimal alkalinity consumption. Based on the occurrence of charge reversal for all chemicals investigated, the mechanism for coagulation was likely charge neutralization. Treatment effect occurred in the ζ-potential span of -14 to +1 mV depending on the coagulant used. Initial turbidity and the ζ-potential are interesting parameter candidates for dosing control in stormwater treatment applications.

  • 40.
    Okwori, Emmanuel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Performance assessment of Swedish sewer pipe networks using pipe blockage and other associated performance indicators2020In: H2Open Journal, E-ISSN 2616-6518, Vol. 3, no 1, p. 46-57Article in journal (Refereed)
    Abstract [en]

    Sewer pipe networks are expected to operate with minimal or no interruptions. The complex nature of randomlyoccurring failures in sewer networks arising from blockages significantly adds to the cost of operation and maintenance.Blockages are significant due to sewage backup or basements flooding, resulting from theiroccurrence. Therefore, continuous performance assessment of sewer pipe networks is necessary to ensurerequired levels of service at an acceptable cost. This study provides insight into the performance of the sewerpipe networks by assessing the proneness of the network to blockages. Furthermore it draws inferences at a holisticstrategic level of influential explanatory factors of blockage proneness, using data available in the SwedishWater and Wastewater Association’s benchmarking system. Results indicate that medium sized municipalitiesare prone to at least 30% more blockages per km per year compared to other municipalities. A hypothesis ofexplanatory factors includes reduced flow volumes and flow depth. Flow velocities below self-cleaning velocityin sewer pipe networks, encouraged by sluggishness of flow are responsible for increased possibility for sedimentdeposition and accumulation in sewers leading to blockages. This is also exacerbated by the deposition of nondisposables(wet wipes, baby diapers, hard paper, etc.), accumulation of fats, oils and grease in sewers andincreased water conservation measures.

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  • 41.
    Nyström, Fredrik
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Nordqvist, Kerstin
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Removal of metals and hydrocarbons from stormwater using coagulation and flocculation2020In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 182, article id 115919Article in journal (Refereed)
    Abstract [en]

    As the understanding of how stormwater pollutants are fractioned and need for mitigation has increased, so has the investigation into more advanced treatment techniques. The present study investigated the treatment efficiency of coagulation/flocculation and sedimentation in semi-synthetic stormwater. Five coagulants were evaluated in terms of reducing particle content, organic carbon, total and dissolved metals, hydrocarbon oil index, and polycyclic aromatic hydrocarbons (PAHs). Changes in the resulting particle size distribution as a consequence of the coagulation treatment were also investigated. The pollutants in the semi-synthetic stormwater were predominantly in the particulate phase. The medium and longer chained hydrocarbons dominated the hydrocarbon oil index, while medium to high molecular weight PAHs were most abundant. Iron chloride was the only coagulant that affected particle size distribution post-treatment, shifting the distribution toward larger particles. In terms of total metal removal, the performance of the coagulants was similar, with over 90% removal on average. Concentration of zdissolved copper, one of the metals found in the dissolved phase, was reduced by 40% via coagulation treatment. The iron chloride coagulant increased dissolved Zn, a change attributed to a considerable drop in pH resulting in higher ion mobility. Similarly, the reduction in organic content (total organic carbon, oil, and PAHs) was over 90% for most coagulants.

  • 42.
    Pericault, Youen
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Risberg, Mikael
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Temperature performance of a heat-traced utilidor for sewer and water pipes in seasonally frozen ground2020In: Tunnelling and Underground Space Technology, ISSN 0886-7798, E-ISSN 1878-4364, Vol. 97, article id 103261Article in journal (Refereed)
    Abstract [en]

    Heat-traced utility corridors (utilidors) can be used in cold regions to install the drinking water and sewer pipes in a shallow trench above the frost depth, thereby limiting excavation needs and the associated economic, social, and environmental costs. Several of these infrastructures were built in the 60s and 70s in Canada, Alaska, Russia, and Norway. More recently, a new type of heat-traced utilidor was built as a pilot project in Kiruna, Sweden to increase the viability of district heating in the area by allowing co-location of all the utility pipes in a shallow trench. Despite several reported cases of undesirably warm drinking water from full-scale projects, previous research efforts on heat-traced utilidors have mainly focused on pipe freeze protection, not on the prevention of excessive temperatures of the drinking water. To ensure comfortable drinking water in terms of taste and smell, an upper temperature limit of 15 °C is usually recommended. The objective of this study was to evaluate the long-term ability of a heat-traced utilidor to maintain sewer temperatures above 0 °C and drinking water temperatures between 0 and 15 °C. Pipe temperatures were measured continuously at two cross sections of a heat-traced utilidor located in Northern Sweden over a period of 22 months. A thermal model, set up and calibrated on the measurements, was used to simulate the impact of extraordinary cold weather conditions on the pipes’ temperatures. The results showed that the utilidor could keep the pipe temperatures within the desired ranges in most cases but that special care should be taken during design to limit drinking water temperatures during the summer.

  • 43.
    Garmabaki, Amir Soleimani
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Marklund, Stefan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Thaduri, Adithya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Underground pipelines and railway infrastructure: failure consequences and restrictions2020In: Structure and Infrastructure Engineering, ISSN 1573-2479, E-ISSN 1744-8980, Vol. 16, no 3, p. 412-430Article in journal (Refereed)
    Abstract [en]

    Underground pipelines are an essential part of the transportation infrastructure. The structural deterioration of pipelines crossing railways and their subsequent failures can entail critical consequences for society and industry, resulting in direct and indirect costs for all the stakeholders involved. Therefore, continuous and accurate condition assessment is critical for the effective management and maintenance of pipeline networks within the transportation infrastructure. The aim of this study has been to identify failure modes and consequences related to pipelines crossing railway corridors. Expert opinions have been collected through interviews and two sets of questionnaires have been distributed to the 291 municipalities in Sweden, with 137 responses in total. The failure analysis has revealed that pipe deformation has the highest impact, followed by pipe rupture at locations where pipelines cross railway infrastructure. For underground pipelines under railway infrastructure, ageing and the external load were awarded a higher ranking than other potential causes of pipeline failure.

    Authors gratefully acknowledge the funding provided by Sweden’sinnovation agency, Vinnova, through the strategic innovation programmeInfraSweden2030. The funding was granted in a competitiveapplication process that assessed replies to an open call for proposalsconcerning “Condition Assessment and Maintenance of TransportInfrastructure (Grant No. 2016-033113)”.

    Authors gratefully acknowledge the technical support and collaboration(In-kind support) of Arrsleff R€orteknik at Sweden, Luleå RailwayResearch Center (JVTC), Stormwater&Sewers and the SwedishTransport Administration (Trafikverket). In addition, the authors arethankful to the anonymous referees for their constructive commentsand Dr Matthias Asplund and Dr Masoud Naseri for their support andsuggestions.

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  • 44.
    Garmabaki, Amir H. Soleimani
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Kumar, Uday
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Thaduri, Adithya
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Laue, Jan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Marklund, Stefan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Odelius, Johan
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Rantatalo, Matti
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Asplund, Matthias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Operation, Maintenance and Acoustics.
    Bansal, Tarun
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Indahl, Stefan
    Rörteknik, Arrsleff, Stockholm- HK, Symmetrivägen 29, 196 02 Kungsängen Sweden.
    A Survey on Underground Pipelines and Railway Infrastructure at Cross-Sections2019In: Proceedings of the 29th European Safety and Reliability Conference (ESREL 2019) / [ed] Michael beer, Enrico Zio, Research Publishing Services, 2019, p. 1094-1101Conference paper (Refereed)
    Abstract [en]

    Underground pipelines are an essential part of the transportation infrastructure. The structural deterioration of pipelines crossing railways and their subsequent failures are critical for society and industry resulting in direct and indirect costs for all the related stakeholders. Pipeline failures are complex processes, which are affected by many factors, both static (e.g., pipe material, size, age, and soil type) and dynamic (e.g., traffic load, pressure zone changes, and environmental impacts). These failures have serious impacts on public due to safety, disruption of traffic, inconvenience to society, environmental impacts and shortage of resources. Therefore, continuous and accurate condition assessment is critical for the effective management and maintenance of pipeline networks within transportation infrastructure. The aim of this study is to identify failure modes and consequences related to the crossing of pipelines in railway corridors. Expert opinion have been collected through two set of questionnaires which have been distributed to the 291 municipalities in the whole Sweden. The failure analysis revealed that pipe deformation has higher impact followed by pipe rupture at cross-section with railway infrastructure. For underground pipeline under railway infrastructure, aging and external load gets higher ranks among different potential failure causes to the pipeline.

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  • 45.
    Vidal, Brenda
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Barraud, Sylvie
    Department of Civil Engineering and Urban Planning, National Institute of Applied Sciences of Lyon.
    Kärrman, Erik
    Division of the Built Environment, Research Institutes of Sweden.
    Herrmann, Inga
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Assessing the sustainability of on-site sanitation systems using multi-criteria analysis2019In: Environmental Science: Water Research & Technology, ISSN 2053-1400, E-ISSN 2053-1419, Vol. 5, p. 1599-1615Article in journal (Refereed)
    Abstract [en]

    Small on-site sanitation systems are widely present in suburban and rural areas in many countries. As these systems often underperform and have an impact on receiving waters, understanding their overall sustainability is of interest for policy and decision-makers. However, the definition and estimation of indicators defining sustainability are challenging, as it is finding the methodological approach to combine qualitative and quantitative indicators into one comprehensive assessment. In this study, twelve indicators defined by environmental, economic, social, technical and health-related criteria were used to compare nine alternatives of on-site sanitation for single households. A non-compensatory method for multi-criteria decision analysis, ELECTRE III, was used for the assessment together with weights assigned to each indicator by a reference group. Several scenarios were developed to reflect different goals and a sensitivity analysis was conducted. Overall, the graywater–blackwater separation system resulted as the most sustainable option and, in terms of polishing steps for phosphorus removal, chemical treatment was preferred over the phosphorus filter, both options being implemented together with sand filters. Assessing the robustness of the systems was a crucial step in the analysis given the high importance assigned to the aforementioned indicator by the stakeholders, thus the assessment method must be justified. The proposed multi-criteria approach contributes to aid the assessment of complex information needed in the selection of sustainable sanitation systems and in the provision of informed preferences.

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  • 46.
    Pericault, Youen
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Bruaset, Stian
    Department of Civil and Environmnetal Engineering, Norwegian University of Technology, NO-7491 Trondheim, Norway.
    Ugarelli, Rita
    Department of Civil and Environmnetal Engineering, Norwegian University of Technology, NO-7491 Trondheim, Norway.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Correcting for the impact of past coordination on the estimation of pipe cohorts survival functions2019Conference paper (Other academic)
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  • 47.
    Panasiuk, Oleksandr
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Ett sätt att upptäckavatten i fel ledning: DTS – Distributed temperature sensing2019Other (Other academic)
    Abstract [sv]

    Det blir många problem för samhälle och miljö när spillvatten är felkopplat till dagvattenledningar, eller när det kommer in tillskottsvatten i spillvattennätet i form av smält snö, dränerings-, grund- eller dagvatten. För att hitta de ledningssträckor eller punkter där de största problemen finns kan man använda metoder som känner av temperaturskillnader mellan spill-, dag- och tillskottsvatten. För smart mätning av temperaturen i avloppsledningar finns en relativt ny metod som mäter kontinuerligt och över långa sträckor – Distributed Temperature Sensing, DTS.

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  • 48.
    Marsalek, Jiri
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Panasiuk, Oleksandr
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Klaffluckor förövervakning av bräddningar2019Other (Other academic)
    Abstract [sv]

    Vanliga klaffluckor i bräddavlopp skulle utan några avancerade instrument kunna användas för att övervaka bräddningar från avloppsledningssystem. Det har visats i ett forskningsprojekt som genomförts inom klustret Dag&Nät där personal från Luleå kommun och forskare vid Luleå tekniska universitet gemensamt har drivit projektet. Med hjälp av vattennivåmätare på vardera sidan om en klafflucka går det att beräkna tryck och flöde. Lösningen är enkel, robust och effektiv när det gäller både drift och kostnader.

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  • 49.
    Okwori, Emmanuel
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Performance assessment of Swedish sewer pipe networks using pipe blockage and other associated performance indicators2019Conference paper (Refereed)
    Abstract [en]

    Sewer networks are expected to operate with minimal or no interruptions. The complex nature of randomly occurring failures in sewer networks arising from blockages significantly adds to the cost of operation and maintenance. Blockages are significant due to sewage backup or basements flooding, resulting from their occurrence. Continuous performance assessment of sewer pipe networks is necessary to ensure a required level of service at an acceptable cost. This study provides insight into the performance of the sewer pipe networks by assessing the proneness of the network to blockages and drawing inferences at a holistic strategic level of influential explanatory factors of blockage proneness, using data available in the VASS statistics database managed by Swedish Water and Wastewater Association. Results indicate that medium sized municipalities are prone to at least 30% more blockages per km per year compared to other municipalities. A hypothesis of explanatory factors includes, reduced flow volumes and design flow depth resulting in flow velocities below self-cleaning velocity in sewer pipe networks encouraging the sluggishness of flow and increased possibility for sediment deposition and accumulation in sewer leading to blockages. This is also exacerbated by the deposition of non-disposables (wet wipes, baby diapers, hard paper etc.), accumulation of FOGs in sewers and increased water conservation measures. Blockages also show a trend indicating occurrence may have a constant return frequency in medium – less than small sized municipalities.

  • 50.
    Søberg, Laila
    et al.
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Viklander, Maria
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Blecken, Godecke-Tobias
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Hedström, Annelie
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Architecture and Water.
    Reduction of Escherichia coliEnterococcus faecalisand Pseudomonas aeruginosa in stormwater bioretention: Effect of drying, temperature and submerged zone2019In: Journal of Hydrology X, ISSN 2589-9155, Vol. 3, article id 100025Article in journal (Refereed)
    Abstract [en]

    The impact of drying and temperature on the reduction of Escherichia coliEnterococcus faecalis and Pseudomonas aeruginosa in stormwater bioretention systems with and without a submerged zone was assessed using 16 pilot-scale bioretention columns under controlled laboratory conditions. The experimental design enabled analysis of possible interactions between the factors. First outflow and event-based samples were collected. Outflow concentrations were independent of inflow concentrations and hence controlled by internal processes. Overall TSS removal was high but sensitive to bacterial synthesis. Event-based samples had significantly higher bacteria concentrations than first outflow samples, suggesting that remaining/surviving bacteria in the bioretention cells have little effect on initial peak outflow concentrations. The effect of temperature varied between bacterial species and sample types. Long dry periods seemed beneficial for bacteria reduction, but outflow bacteria concentrations peaked during the second watering after long dry periods. Submerged zones significantly reduced bacteria outflow concentrations. However, sudden temperature increases caused bioretention cells with a submerged zone to produce significantly higher bacteria outflow concentrations than before the temperature increase, which was not the case for standard cells. Bioretention cells with submerged zones may thus be poor choices for reducing bacterial concentrations in stormwater runoff in areas experiencing winter conditions. Finally, our results suggest that adsorption (e.g. further enhanced by biofilm formation) is the major mechanism governing bacteria reduction in bioretention systems.

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