With rapidly urbanizing societies, waste management needs attention. In 2008, EUs Waste Framework Directive (WFD) set new concepts, like reducing usage of natural materials. Thus, the interest for alternative materials increased. In Skellefteå, since the 1970’s, iron sand has often substituted natural gravel in road construction. But, today stricter regulations might forbid iron sand for further use. The issue is whether leachate from iron sand causes heavy metal pollution or not. This thesis tried to provide more knowledge into iron sand’s environmental impact. In order to investigate this, a sediment sample (<53 cm deep) collected in Inre-viken, a lake 50m from a road with iron sand, were analyzed for Zn, Pb and Cu concentrations. Enrichment factor (EF), national benchmarks, and reference data were used to evaluate anthropogenic impact and age-determine the sediment. The results showed: (1) Inre-viken has elevated heavy metal levels compared to pre-industrial levels, with highest Cu (133 mg/kg) and Zn(204 mg/kg) concentrations found in the surface layer. (2) Zn and Cu showed an increase between 41-0 cm depth (1970-2015), but only Cu reaches high concentrations, while Zn and Pb range between low to very low concentrations. (3) The metal enrichment is low compared to the reference lake. The findings show that there are elevated levels in Inre-viken compared to pre-industrial levels. However, identifying the main source of pollution is difficult, because many pollution sources exist in the area. To determine if iron sand is the culprit, further studies are necessary.

This dissertation focuses on (river) forecasting, but also includes a study on stormwater treatment. Using forecasts for decision-making is complicated by their inherent uncertainty. An interview-based study qualitatively and a survey empirically investigate forecast use in emergency management. Emergency managers perceive uncertainty as a given rather than as a problem. To cope with the uncertainty, decision-makers gather as much information as possible; forecasts are only one piece of information among many. For decision-making, emergency managers say that they rely more on radar than on river forecasting. However, forecasts play an important role in communication with the public, because they are the official interpretation of the situation. Emergency managers can add a lot of value to those forecasts by combining them with local knowledge, but might not do so because of accountability concerns. Forecasts must have value to emergency managers, because those with more work experience rely more on them than those without. Another study further develops the application of quantile regression to generate probabilistic river forecasts. Compared to existing research, this study includes a larger number of river gages; includes more independent variables; and studies longer lead times. Additionally, it is the first to apply this method to the U.S. American context. It was found that the model has to be customized for each river gage for extremely high event thresholds. For other thresholds and across lead times, a one-size-fits-all model suffices. The model performance is robust to the size of the training dataset, but depends on the year, the river gage, lead time and event threshold that are being forecast. An additional study considers the robustness of stormwater management to the amount of runoff. Impervious surfaces, such as roads and parking lots, can increase the amount of runoff and lead to more pollution reaching streams, rivers, and lakes. Best Management Practices (BMPs) reduce the peak discharge into the storm sewer system and remove pollutants such as sediments, phosphorus and nitrogen from the stormwater runoff. Empirically, it is found that BMP effectiveness decreases sooner, steeper and deeper with increasing sizes of storm events than assumed in current computer models.

Pervious concrete pavement has the capacity to perform as two types of infrastructure: a pavement; and a stormwater management solution. It is a low impact development as it does not alter the natural hydrological cycle when implemented, unlike a conventional impermeable pavement. This research represents some of the initial investigations into pervious concrete pavement in Canada. The two research hypotheses of this research were the following: 1. Pervious concrete pavement can be successfully planned, designed, constructed and maintained in Canada for successful performance based on surface evaluations of permeability rate and surface condition. 2. Verification that the subsurface drainage capabilities of pervious concrete pavement are as described in literature and can be quantified using instrumentation. Through monitoring of the design, construction, performance and maintenance of five field sites across Canada and various laboratory pavement slabs, the behaviour of pervious concrete pavement in freeze-thaw conditions has been evaluated. This thesis presents the findings from the various phases of the life cycle of pervious concrete pavement: planning; design; construction; and maintenance. An interpretation of the performance of pervious concrete pavement both from the perspective of the surface and subsurface is included. The various field sites led to pervious concrete being used in areas exposed to static or parked traffic and areas with slow moving traffic. At the two sites that included static and slow moving traffic, the permeability performance was better in the areas of static traffic than those with moving traffic. Each of the field sites had a unique mix design and some had multiple variations of one basic mix design. The relationship between the void content and hardened density of the pervious concrete cores was linear with none of the cores being visually identified as outliers. Substantial deterioration in pavement structure performance was identified at one site. Other field sites showed changes in structural capacity over the monitoring timeline. However, no locations of substantial decreases in structural capacity were identified. The surface condition of the sites over the analysis period indicated that compaction to the surface during construction was helpful in constructing a quality pavement. The results of the project indicated that pervious concrete will crack when joints are not included and may also crack similarly to conventional impermeable concrete pavements if joints are spaced too widely or do not match joints of adjacent pavement. Washing the pervious concrete pavement surface with a large hose or garden hose was found to be the most effective in improving permeability across a site and also in increasing the permeability of the pervious concrete. The initial permeability of the pervious concrete pavement was found to influence future performance. Freeze-thaw cycling and moisture were found to alter the internal structure of pervious concrete. However, did not generally lead to surface distress development. The application of sand as a winter maintenance method decreased the permeability, as did the use of a salt solution. However, neither winter maintenance method led to the permeability rates of laboratory slabs dropping below an acceptable level. All three slabs loaded with a salt solution deteriorated to a point where the slabs had failed. The initial permeability of the field sites proved to be important and although some sites started with what appeared to be very high permeability rates, these sites were successful in the multiple year evaluation in maintaining adequate permeability rates. The types of surface distresses that developed in the cores and slabs in the laboratory were generally not substantially worse at the field sites, suggesting that pedestrian and vehicle traffic do not necessarily escalate distresses caused by the Canadian climate and corresponding winter activities. The subsurface drainage that was quantified by the instrumentation included in three field sites confirmed observations from the surface of the pavement and exceeded other expectations. Two field sites exhibited limited drainage capabilities on the surface of the pervious concrete pavement, one shortly after construction, and the other within a year following construction. The subsurface analysis quantified and confirmed that moisture was not able to drain completely vertically through the pavement structures at these two sites due to the limited access in the pervious concrete pavement surface. In comparison, the subsurface drainage at another site surpassed the assumed behaviour of pervious concrete pavement structures. The pavement structure in general at this site was highly permeable and this was identified as moisture was not observed to be collecting in the bottom of the storage base layer at any time or for any period of time. The successful overall drainage performance of this site demonstrates the ability to effectively use pervious concrete pavement in Canada.

In Alberta, almost all created wetlands accepted as compensation have been naturalized stormwater management facilities. Our investigation of 32 created and natural wetlands in central Alberta determined that created wetlands have steeper shoreline slopes, largely as a result of their primary function as stormwater retention ponds. This resulted in distinctly different vegetation zonation, with the steeper slopes of created wetlands resulting in fewer, narrower wetland vegetation zones. This was reflected in reduced species richness and abundance of wetland songbirds at created wetlands. This study also discusses the development of a Floristic Quality Assessment (FQA) approach, a standardized, quantitative approach to measuring wetland condition, for Albertas Parkland and Boreal natural regions. I present plant survey data from the 32 wetlands as validation of the effectiveness of this approach. This study provides information on current wetland compensation practices and a potential wetland assessment tool; both topics that are directly relevant to the implementation of wetland compensation policies in Alberta. / Ecology

Accurate and reliable estimations are the most important factors for the development of efficient stormwater pollutant mitigation strategies. Modelling is the primary tool used for such estimations. The general architecture of typical modelling approaches is to replicate pollutant processes along with hydrologic processes on catchment surfaces. However, due to the lack of understanding of these pollutant processes and the underlying physical parameters, the estimations are subjected to gross errors. Furthermore, the essential requirement of model calibration leads to significant data and resource requirements. This underlines the necessity for simplified and robust stormwater pollutant estimation procedures. The research described in this thesis primarily details the extensive knowledge developed on pollutant build-up and wash-off processes. Knowledge on both build-up and wash-off were generated by in-depth field investigations conducted on residential road and roof surfaces. Additionally, the research describes the use of a rainfall simulator as a tool in urban water quality research. The rainfall simulator was used to collect runoff samples from small-plot surfaces. The use of a rainfall simulator reduced the number of variables which are common to pollutant wash-off. Pollutant build-up on road and roof surfaces was found to be rapid during the initial time period and the rate reduced when the antecedent dry days increase becoming asymptote to a constant value. However, build-up on roofs was gradual when compared to road surfaces where the build-up on the first two days was 66% of the total build-up. Though the variations were different, it was possible to develop a common replication equation in the form of a power function for build-up for the two surface types with a as a multiplication coefficient and b as a power coefficient. However, the values for the two build-up equation coefficients, a, and b were different in each case. It was understood that the power coefficient b varies only with the surface type. The multiplication coefficient varies with a range of parameters including land-use and traffic volume. Additionally, the build-up observed on road surfaces was highly dynamic. It was found that pollutant re-distribution occurs with finer particles being removed from the surface thus allowing coarser particles to build up. This process results in changes to the particle size composition of build-up. However, little evidence was noted of re-distribution of pollutants on roof surfaces. Furthermore, the particulate pollutants in both road and roof surfaces were high in adsorption capacity. More than 50% of the road and more than 60% of the roof surface particulates were finer than 100 μm which increases the capacity to adsorb other pollutants such as heavy metals and hydrocarbons. In addition, the samples contained a significant amount of DOC which would enhance the solubility of other pollutants. The wash-off investigations on road and roof surfaces showed a high concentration of solid pollutants during the initial part of events. This confirmed the occurrence of the 'first flush' phenomenon. The observed wash-off patterns for road and roof surfaces were able to be mathematically replicated using an exponential equation. The exponential equation proposed is a modified version of an equation proposed in past research. The modification was primarily in terms of an additional parameter referred to as the 'capacity factor' (CF). CF defines the rainfall's ability to mobilise solid pollutants from a given surface. It was noted that CF varies with rainfall intensity, particle size distribution and surface characteristics. Additional to the mathematical replication of wash-off, analysis further focused on understanding the physical processes governing wash-off. For this, both particle size distribution and physicochemical parameters of wash-off pollutants were analysed. It was noted that there is little variation in the particle size distribution of particulates in wash-off with rainfall intensity and duration. This suggested that particle size is not an influential parameter in wash-off. It is hypothesised that the particulate density and adhesion to road surfaces are the primary criteria that govern wash-off. Additionally, significantly high pollutant contribution from roof surfaces was noted. This justifies the significance of roof surfaces as an urban pollutant source particularly in the case of first flush. This dissertation further describes a procedure to translate the knowledge created on pollutant build-up and wash-off processes using small-plots to urban catchment scale. This leads to a simple and robust urban water quality estimation tool. Due to its basic architecture, the estimation tool is referred to as a 'translation procedure'. It is designed to operate without a calibration process which would require a large amount of data. This is done by using the pollutant nature of the catchment in terms of buildup and wash-off processes as the basis of measurements. Therefore, the translation procedure is an extension of the current estimation techniques which are typically complex and resource consuming. The use of a translation procedure is simple and based on the graphical estimation of parameters and tabular form of calculations. The translation procedure developed is particularly accurate in estimating water quality in the initial part of runoff events.

Thesis (M.E.S.)--Evergreen State College, 2003. / Title from title screen viewed (4/15/2009). Includes bibliographical references (leaves 56-58).

Thesis (M.E.S.)--Evergreen State College, 2007. / "June, 2007." Title from title screen (viewed 4/8/2010). Includes bibliographical references (p. 52-54).

<p>Although wood floor production does not use water in the production process, water consumptionis related to cleaning and washing of floor and machineries in different steps of the process line,which generate a number of small flows that are highly polluted.Besides this, the industry has a need to store large amounts of wood outside to be able to havecontinuity in the production. This takes up a lot of space outdoors and once it rains the water thathas been in contact with wood, oil and metals forms stormwater, which transports pollutants.Stormwater has for a long time not been seen as a problem and has often been discharged intorecipient water bodies without any treatment. During cold seasons, this also involves snowmelt thatcan transport high concentrations of different pollutants.This report describes the composition of process- and stormwater from a wood floor industry inNybro, Sweden regarding parameters such as COD, phenol, tannin and lignin. The concentrationsof phenols in the stormwater were found in a range considered toxic to marine life.Regarding the process water, high values was found for COD (Chemical Oxygen Demand) and forother substances and elements potentially toxic (e.g. formaldehyde, wood resins, detergents andmetals). If these waters are directly released to a sewage treatment plant without any pre-treatmentprocess it can disturb the plant treatment efficiency; if released to a recipient water body, it cancause oxygen deficiency and consequently, death to marine life.The possibility of reducing the levels of pollutants through the use of electrocoagulation has beenexamined in this study. This has been done both for process water and stormwater from the woodfloor industry. A 250 ml batch unit for electrocoagulation EC was setup with iron (Fe) andaluminium (Al) electrodes for treating process water and stormwater. The results show that the ECprocess can reduce COD concentration from stormwater at least 70%. On the other hand, lessefficiency of EC for treating process water was observed.A method for simulating a snowmelt period in lab scale was also developed. Snow collected from awood floor industry was melted according to real temperature and the quality of these samples hasthen been compared to on-site samples of stormwater</p> / Development of an integrated approach for industrial wastewater and stormwater management in the wood-industry sector

Stormwater is rain, melt and rinse water that temporarily runs off the ground surface. In cities with many impermeable surfaces large amounts of stormwater may be formed. Stormwater is diverted through conduits and ditches to recipients. If the diversion of stormwater is insufficient flooding can occur. Stormwater contains contaminants from the catchment surfaces such as nutrients, heavy metals, bacteria, organic compounds and oils. To study stormwater pollution and flows various stormwater modelling tools are used. The purpose of this thesis is to test, compare and evaluate four stormwater modelling tools and conclude their strengths and weaknesses. This was done by a literature study, a market research, definition of evaluation criteria and by testing the tools on a case study of an industrial and residential area in Scotland. The main developed evaluation criteria was model characteristics, required input, user friendliness, output and model application. The four selected tools were StormTac, Infoworks CS, SuDS Studio and MUSIC. The case study included both flow and pollutants on a yearly basis and for a rainfall event. The results from the study were compared against observed values both before and after calibration. No model gave good model predictions for all parameters. The observed volumes of water were larger than modelled for all four models even after calibration. An intercomparison between the models however gave a better fit. Regarding pollutants, the model predictions compared with observed values varied between the tools and substances. Strengths with StormTac are that it includes over 70 pollutants, includes the recipient and gave good model predictions for pollutant concentrations when compared with observed pollutants. A weakness is that StormTacs automatically calculated base flow was much smaller than observed in the case study and the tool is not suited for studies of single event rainfalls.Strengths with Infoworks CS are that it is fully distributed, a complete network is built up and the tool can be used for design of networks, flood predictions and flows over time. It is time consuming to build a model in Infoworks CS, few default pollutants are included and it gave poor model predictions for nitrogen concentrations in the case study. SuDS Studio is a unique tool for defining suitable options for retrofitting SuDS solutions and this is a strength as it is the only tool of its kind. SuDS studio gave large intervals for pollutant loads in the case study which can be difficult to interpret. A strength with MUSIC is that it is user friendly and can be used for comparing water quality pre and post treatment. It does however only include three default pollutants in the model, and only three pollutants can be modelled at a time.

abstract: More than half of all accessible freshwater has been appropriated for human use, and a substantial portion of terrestrial ecosystems have been transformed by human action. These impacts are heaviest in urban ecosystems, where impervious surfaces increase runoff, water delivery and stormflows are managed heavily, and there are substantial anthropogenic sources of nitrogen (N). Urbanization also frequently results in creation of intentional novel ecosystems. These "designed" ecosystems are fashioned to fulfill particular needs of the residents, or ecosystem services. In the Phoenix, Arizona area, the augmentation and redistribution of water has resulted in numerous component ecosystems that are atypical for a desert environment. Because these systems combine N loading with the presence of water, they may be hot spots of biogeochemical activity. The research presented here illustrates the types of hydrological modifications typical of desert cities and documents the extent and distribution of common designed aquatic ecosystems in the Phoenix metropolitan area: artificial lakes and stormwater retention basins. While both ecosystems were designed for other purposes (recreation/aesthetics and flood abatement, respectively), they have the potential to provide the added ecosystem service of N removal via denitrification. However, denitrification in urban lakes is likely to be limited by the rate of diffusion of nitrate into the sediment. Retention basins export some nitrate to groundwater, but grassy basins have higher denitrification rates than xeriscaped ones, due to higher soil moisture and organic matter content. An economic valuation of environmental amenities demonstrates the importance of abundant vegetation, proximity to water, and lower summer temperatures throughout the region. These amenities all may be provided by designed, water-intensive ecosystems. Some ecosystems are specifically designed for multiple uses, but maximizing one ecosystem service often entails trade-offs with other services. Further investigation into the distribution, bundling, and tradeoffs among water-related ecosystem services shows that some types of services are constrained by the hydrogeomorphology of the area, while for others human engineering and the creation of designed ecosystems has enabled the delivery of hydrologic ecosystem services independent of natural constraints. / Dissertation/Thesis / Ph.D. Biology 2010