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259 Uppsatser om Stormwater sampling - Sida 1 av 18

Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning

Stormwater run-off from surfaces such as roads or rooftops is often polluted with heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.

Ekologisk dagvattenhantering på parkeringsytor : Lösningsförslag för Eurostop köpcentrum i Halmstad

Stormwater from trafficked areas often contains high pollution levels. In traditional stormwater management design, stormwater is first transported away through piped networks, and then in most cases passes through oil separators before finally reaching the recipients. While this traditional method removes certain pollutants from the stormwater, it does not reduce the total flow, as in the case of ecological stormwater management. In the ecological method the stormwater is not simply transported away, but is recirculated through infiltration, percolation, and detention. The aim of this study is to investigate possible advantages of ecological management designs, in contrast to traditional management.

Dagvattenhantering i den täta staden

This thesis adresses the subject of stormwater management and the problematic with stormwatermanagment and landuse in the compact city. The thesis research different solutions in stormwater managment and how to implement them in the context of the compact city. And at the same time preserve and make good recreaational places and keep quality green land per capita. The thesis also analyses risks and problems that could effect the environment with focus on stormwater managment and hov to minimize these problematic factors an create a good environment. In an urban context where the water has a natrual place, and is used as a asset.

Lyviken : -bedömning av dagvattenkvalitet

AbstractStormwater is defined as rain- and melted water. Ludvika kommun had little knowledgde about the stormwater that reaches a specific recipient Lyviken. Therefore they intended to do an research of the stormwater that leads down to Lyviken. The aim with this study was to assess the quality of the contents in the stormwater based on pH, conductivity, phosphorous, nitrogen, bacterias, oil and one sample that meassured the value of several methals. Since the population has increased for decades, the area of hard surfaces and asphalts areas also has increased. This can increase the pollutions that finally ends up in the recipient.

Utvärdering av datorprogram för användning vid dagvattenutredningar

The main object of this diploma work thesis is about how computer programs can bea tool to use for work on stormwater investigations. The advantage of using acomputer program compared with calculations made by hand is evaluated anddiscussed. The computer programs that have been used for studies and a sequence oftesting of the possibilities are Autodesks Storm and Sanitary Analysis and DHIs MikeUrban.Focus on sustainable development now permeates the building industry. As a resultstormwater investigations have been conducted in an increasing extent the recentyears. Stormwater is water produced due to precipitation, such as rain and snowmelt.Stormwater investigations normally contain descriptions of existing land use, plannedland use and suggestions of measures and technical solutions for the future disposal ofstormwater.The initial part of the thesis consisted of literature studies on stormwater andstormwater investigations to understand the science.

Metaller i dagvatten - Effekter i recipient : En analys av koppar, kdamium och zink i dagvatten från en parkering i Halmstad, Sverige

When stormwater occurs near human activity the water gets polluted. The purity and composition vary widely depending on the types of activities in the area, the type of surface the water comes in contact with, precipitation and many more parameters. It has long been known that stormwater quality can affect both human health and the environment as stormwater is a major contributor to pollution of receiving waters.A human activity that has an impact on the environment in several different ways is traffic and stormwater is no exception. Airborne gases that react with precipitation, oil leaks and fuel systems that drops down on the ground, metals from brake linings and rubber particles from tire wear are some of the aspects you have to take into account when categorizing the relationship between traffic and polluted stormwater.In this project, stormwater samples from a parking lot in Halmstad, Sweden were collected and analyzed with an atomic spectrophotometer. The presence and relationship between copper, cadmium and zinc with different rainfall parameters have been studied.

En jämförelse av stickprovsmetoder vid mätning av radioaktivetet på en yta

This study compares the sample variance of the mean in a simple random sample (SRS) and a systematic sample from a surface. The study also compares the prediction error variance in a SRS and systematic sample from a random field. Recommendations are presented on which method to use in the clearance and exemption process in the nuclear industry. The results indicate that quadratic systematic sampling outperformed SRS in most instances and proved to be especially efficient in the presence of a long-ranged covariance function and high sampling intensity (i.e. short distances between observations).

Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS

The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.

Lawsonia intracellularis : utvärdering av provtagning med tops : utvärdering av provtagningsteknik med tops vid diagnostik av Lawsonia intracellularis hos tillväxtgrisar

Lawsonia intracellularis is an important pathogen in the intestine, causing diarrhea and retarded (or poor) growth in pigs. Diagnostics is based on sampling of small amounts of faeces. Several publicated scientific papers mention the use of faecal swabs as sampling material for diagnosis in experiments and in prevalence studies. Therefore the need of an evaluation of this sampling technique is urgent since, to our knowledge, this has not previously been done. Here reported work compare the use of rectal swabs for feacal sampling, with sampling and analysis of 0.1-0.2 gram of faeces. The studie included twelve herds with a case history of earlier or ongoing problems with diarrhoea where Lawsonia intracellularis could be suspected as the causative agent. A total of 120 growing pigs where examined.

Riskbaserat provtagningsprogram för mikroorganismer i Gäddviks vattentäkt

Risk-based sampling program of microorganisms in the water source in northern SwedenAfter several disease outbreaks caused by parasites in the drinking water during the last years, it is more essential than ever to insure that the water supply companies have enough barriers to counteract the presence of microorganisms in the outgoing water. It is also discussed whether climate changes such as increased precipitation can have a connection to the increased cases of parasites in water sources. The water source at Gäddvik is Luleå municipality?s largest and provides drinking water to 64 500 of Luleå?s 74 000 inhabitants. The investigation of microorganisms in the water source, especially in the Lule River has not been as prioritized as the sampling of chemical parameters.

Handlingsplan för rening av dagvatten från hårt trafikerade gator i Örebro

The main purpose with the project has been to approximate the magnitude of the pollution transport from the actual road surfaces and to get an approximation of the possibility to collect the pollutants to reduce the load to the water and improve the water quality.The quantity of pollution transport from the most trafficated roads areas in Örebro city has been calculated. Roads whith a traffic exceeding 10 000 vehicle/day. The study has been done with the calculation tool StormTac. Through analysis of traffic loads and road surface, which together with a different kinds of parameters gives an approximation of the pollutant transport.The calculation has included some metals and other substances in the stormwater and has also included the present of suspended solids. Included the overall study, some smaller areas has also been calculated for the possibility to remove pollutants.The work also includes calculation for three different areas for stormwater treatment.

Känslighets- och osäkerhetsanalys av parametrar och indata i dagvatten- och recipientmodellen StormTac

Three methods of sensitivity and unceartainty analysis have been applied to the operative stormwater- and recipient model StormTac. The study area is the watershed of lake Flaten in the municipality Salem. StormTac?s submodels for stormwater, pollutant transport and the recipient are cosidired. In the sensitivity assessment, the model parametres and inputs were varied one at a time by a constant percentage according to the ?one at a time? (OAAT) method and the response of the outputs were calculated.

Dagvattnets föroreningar som potentiellt hot för en god ekologisk och kemisk status i ytvattnet : En kartläggning av Vallentuna tätorts dagvattenhantering utifrån dess tillsynsbehov

The EU's Water Framework Directive aims to a long-term and sustainable use of our water resources and wants to ensure good water quality in Europe's water bodies. Discharge of polluted stormwater into receiving waters can be a threat to their ecological and chemical status. Municipalities are responsible for supervision of the environmental quality standards (EQS) and therefore need to gain knowledge of current stormwater management, the expected level of pollution emissions and possible appropriate purification steps to ensure that the goal of good water quality is achieved.This master thesis aims to provide this knowledge in the example case of Vallentunas urban area and wants to prepare future oversight so that it can be assessed how much the discharge of polluted stormwater into the local receiving water is a threat to its status. With the help of maps, aerial photographs, site observations and individual discussions those areas are mapped where appearance of moderate to highly polluted stormwater could be suspected. The degree of pollution at the discharge points is determined based on land use upstream and uses standard values according to the administrators assistance "Tillsyn av dagvatten" (MSL 2014).The study identifies 100 areas in need of supervision regarding their stormwater management.

Advantages and disadvantages of different observation methods on a troop of wild olive baboons at a river in Southern Kenya

Every observation method has its advantages and disadvantages and a well-adopted method gives more reliable results. Factors affecting the choice of the most appropriate methods for recording foraging behaviours include species, group size, environment, seasons and age. The focus for this study was to determine which method is most appropriate for studying the foraging behaviour of a troop of 89 olive baboons (Papio anubis) living in a riverine forest by the Southern Ewaso Ng'iro River by Lale'enok Resource Centre in Kenya. To determine this, a literature study was carried out to compare methods from monkeys and apes. I found instantaneous sampling was the most common method with intervals of 5 minutes in most cited studies.

Utveckling och utförande av frekvensstudie vid Rapid Granulator AB

The object of this examination project is to produce a method of work sampling at Rapid Granulator AB. The aim is to perform the method at the company and evaluate if it is executable. The study is delimited to the basic construction of the 45-series in the assembly hall.Preparations to produce the method of the work sampling resulted in definitions of activities, a form and a product tree. Several days were spent studying the assembling to learn and understand the entirety.The work sampling result showed a large amount of no value adding time that was used in the assembling. Some of the activities could be reduced and we observed some problems during the assembly process.

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