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159 Uppsatser om Stormwater harvesting - Sida 1 av 11
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.
Simulation of rattan harvests in Indonesia : different harvesting pressures and the resulting patterns
The objectives of this research were to determine whether the natural rattan resources in Sulawesi, Indonesia can cope with the strongly increased harvesting pressure that has occurred over the last centuries. I was furthermore looking for patterns in the rattan population dynamics that might give a hint on how the harvesting system could be improved to ensure a maximum sustainable yield. To
answer these questions, I developed an individual-based model to analyse the dynamics of rattan growth in connection with rattan harvests by locals to identify sustainable levels of rattan harvests around villages in Sulawesi, Indonesia. Scenarios with different harvesting intensities were run to compare the change in harvest amount. For a given harvesting pressure, scenarios with a high number of harvesters and a low harvesting frequency had the same effect as scenarios with high harvesting frequencies and a low number of harvesters.
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.
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.
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.
Detektor på skördare för utsortering av träd med metallskrot
Fortifikationsverket which is the landlord for the Swedish national defence has a great problem in their forestry due to the relatively large amount of metal objects in their timber. These metal objects cause different types of economical losses in the timber refinement chain. To enable out sorting of logs containing metal objects already in the harvesting phase, Fortifikationsverket is interested of the possibility to utilize some type of metal detector in a harvesting head for that purpose.The goal of this study was to, with help of a case study, enlighten the problem that metal objects in timber cause for Fortifikationsverket and their customers of timber and to investigate conditions of to mount and utilize some kind of metal detector in a harvesting head at present.The saw timber deliveries by Fortifikationsverket during the time period 2003-2005 was used as a reference volume for calculations of economical losses. In this case study was included two sawmills where timber from Fortifikationsverket were delivered to for further refinement. Factors investigated were the type of damage metal objects caused in these two sawmills and the economical signification of these damages.
GPS- & GIS-användning i drivningsprocessen hos Stora Enso SKog AB :
GPS (Global Positioning system) and GIS (Geographical information system) has been used for planning and inventory in the forest sector for more than ten years. The last years the development has come to equip harvesters and forwarders with GPS and GIS (GIT).
The goal with this study was to reach a basis for decision, how Stora Enso Skog should continue its investment in GPS and GIS in harvesters and forwarders. To reach this basis for decision, possible advantages and benefits, disadvantages and problems in the harvesting process was evaluated. The study was made as an interview study with four harvesting managers and ten machine teams. To secure the quality of the results an interview questionnaire was made before the interviews were done.
The results showed that GIT will make the harvesting managers work easier.
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.
Bättre åtkomst till avverkningstrakter med anpassat marktryck från avverkningsmaskinerna
The global climate-change means increasing mean-temperature and higher precipitation in Sweden, which leads to shorter periods of frozen ground in the forest. At the same time the harvesting machines are getting bigger and more powerful. The forest industry aim at an even wood flow, and the ground damage has to be as low as possible. The two biggest causes for ground-damage is the bearing capacity of the forest ground and the ground-pressure of the harvesting machines. The aim of this study was to find out some rules for the machine choice considering ground pressure, when harvesting on ground with low bearing capacity.A field study, using a Valmet 890.3 forwarder, was carried out where different ground pressures and their effect on the ground were tested on two different types of ground.Additionally, an inventory of damaged harvesting grounds was made.
Dagvattenhantering och takpark för projektet PARK 1 : Ett utredande förslag
Som följd av den pågående urbaniseringen har de naturliga förutsättningarna för regn och smältvattnet att infiltrera i marken och återgå till sitt kretslopp på naturlig väg försvunnit i städerna. I Stockholm leds ungefär hälften av dagvattnet via VA-nätet direkt och orenat till reningsverken. Dagvattenflödet varierar kraftigt vilket orsakar toppar som överbelastar VAnätet och är svåra för reningsverken att hantera. Istället för att ledas ut i VA-nätet ska dagvatten strävas efter att hanteras lokalt. Arbetet lägger fokus på dagvattenhanteringen för takparken på ett nybyggnadsprojekt i Stockholm, projektet PARK 1.