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Highway runoff, as a nonpoint source, may exert significant pollutant load on the catchment. Finding ways to mitigate nonpoint sources of pollutants is a matter of great concern for improving water quality. It was cited by the Environment Agency in 2005 that more than 80% of English rivers were at risk of failing to achieve Water Framework Directive (WFD) objectives through diffuse pollution (Faram, 2007; p.14). The presence and behaviour of metals were analysed and compared through seasonal sampling from one of the most trafficked roads in the Midlands, M1. These were compared with other sources: local streams and sewage works. The concentration of metals in stormwater from the M1, three neighbouring rural brooks and three local sewage works, all in the same catchment, were sampled. Three metals (Fe, Cu and Zn) were used as an indicator because of their predominance and potential harmful effect on biodiversity. The data was analysed to establish any links between the total and dissolved metals and standard water quality parameters. The thesis also examines the performance of a standard highway treatment system of interceptor and lagoon for removing metals. The results indicate that evaporation and de-icer salts had the strongest effect on metal concentrations and their solubility in the runoff from the M1. As additional factors, rainfall intensity and antecedent dry weather period (ADWP) had the most important influence on metal concentrations. Fe was always at the highest concentrations for all weather conditions (total and dissolved) and all sampling locations. The results also showed that Fe was affiliated with the particulate matter; however, it was also suggested that it was solubilised by anaerobic conditions. Zntot during wet weather exceeded the environmental quality standards (EQS) both on the M1 and in Woodbrook. The sewage work effluent did not exceed the EQS at any time of sampling. It was also found that Zn solubility was increased by the presence of de-icer salts which released it from the sediment by a process of ion-exchange, as suggested by the literature. Cu concentrations had the most erratic values and varied widely but were in the lowest concentrations compared to other metals. During wet weather Cudis from the M1 runoff exceeded the EQS. It was also concluded that the analytical and sample preservation methods chosen could have an effect on the concentrations of copper. Filtration with recycled glass and pea-gravel was able to remove particles down to 5 μm, but at the typical flow rate (5 m/hr), and solids loading the filters would need regular washing. The adsorption studies showed that metals are more effectively removed by alkaline conditions than acid conditions which release metals into the environment.

Vandenų apsauga yra viena iš svarbiausių aplinkosaugos sričių. Europos Sąjungos direktyvos griežtai reglamentuoja išleidžiamų į paviršinius vandenis miestų nuotekų kokybę. Ne mažiau kaip 80 procentų išleidžiamų nuotekų neturi viršyti didžiausios leidžiamos koncentracijos. Darbo tikslas ištirti nuotekų valyklų Raseinių rajono savivaldybėje darbo efektyvumą ir numatyti priemones jų darbui pagerinti. Darbe analizuojama Raseinių rajono (Raseinių, Ariogalos, Kaulakių gyvenviečių) nuotekų valyklų darbo efektyvumas. Analizei naudoti 2005-2007 metais atliktų tyrimų duomenys. Duomenų analizė parodė, kad visoms valykloms reikalinga rekonstrukcija, visose gyvenvietėse reikia didinti prie centrinės nuotekų šalinimo sistemos prisijungusių gyventojų skaičių. / The protection of water is one of the most important spheres in the environment control. The quality of cities‘ sewage, that is drained to surface water, is strictly regulated by the directives of European Union. Not less than 80 per cent of drained sewage must not exceed the maximum allowable concentration. The purpose of this research is to analyse the effectiveness of sewage works in Raseiniai district and to provide the plant improvement scheme. In the article there is discussed the effectiveness of sewage works in Raseiniai district (Raseiniai, Ariogala, Kaulakiai). The data of 2007 is used in the analysis. The results show that the reconstruction is necessary for all the sewage works. Moreover, in all the places of residence it is a must to increase the number of residents who are linked to the central sewage removal system.

River water is used for a range of purposes, for example irrigation, laundry, hygiene, mining of sand, as drinking water and for disposal of wastes and wastewater. These anthropogenic activities, along with agriculture and the local climate and geology will have effects on the water quality, and by extension the people living in the area. This study intends to evaluate the water quality of Likangala River, which is a perennial river in southern Malawi, during hot dry season linking it to the activities present in the direct vicinity of the urban segment of the river. A small land use survey was carried out, and eight points for water sampling chosen for analysis of a set of physio-chemical water quality parameters. Also an estimate of the water discharge of the time was made. It was found that most parameters were within the guidelines for drinking water set up by WHO (2011) and Malawi Bureau of Standards (MBS, 2008), although turbidity, manganese, iron, chromium and lead showed elevated levels. Some, but not all, parameters showed a trend with low values upstream the city and higher values downstream (except pH with a inverse trend), and almost all parameters were significantly higher in the effluents from the Zomba Sewage Works, and also directly afterwards. / Flodvatten används för en rad olika ändamål, exempelvis bevattning, tvätt, hygien, utvinning av sand, som dricksvatten och för avyttrande av avfall och avloppsvatten. Dessa mänskliga verksamheter, tillsammans med effekter av jordbruk samt det lokala klimatet och geologin kommer att påverka vattenkvaliteten, och i förlängningen de människor som bor i området. Denna studie avser att utvärdera vattenkvaliteten i Likangala, som är en flod i södra Malawi, under heta torrperioden och koppla denna till de verksamheter som finns i dess direkta närhet längs den urbana sträckningen av floden. En liten kartläggning av markanvändning genomfördes, och åtta platser för vattenprovtagning valdes ut för analys av ett antal fysio-kemiska vattenkvalitets- parametrar. Också en uppskattning av vattenföring gjordes. Det visade sig att de flesta parametrar var inom riktlinjerna för dricksvatten som inrättats av WHO (2011) och Malawi Bureau of Standards (MBS, 2008), även om turbiditet, mangan, järn, krom och bly visade förhöjda halter. Vissa, men inte alla, parametrar visade en trend med låga värden uppströms staden och högre värden nedströms (förutom pH med en inverterad trend), och nästan alla parametrar var betydligt högre i spillvattnet från Zomba vattenreningsverk, och även direkt efteråt.