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The mobile septage dewatering trucks are a new alternative to the more common practice for septage handling. The greatest advantage of the system is that the septage is treated at the point of production to the degree that it can be delivered directly to local farmers. Two systems are evaluated; Hamstern by the Mattsson Group […]

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The relationship between total aluminium concentration and acidity was studied in water from 14 forest brooks. From the individual brook between 10 and 26 water samples were taken distributed over different parts of one to four consecutive years. All samples were taken during the period 1982-1986. For the whole material pH varied between 4.1 and […]

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A sufficient coagulant dose is essential in order to obtain chemically treated humic surface water of satisfactory quality. But it is bad economy to apply too high a dosage just to be on the safe side. Studies at water treatment plants with large variations in the raw water humic content have shown that efficient supervision […]

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As a result of new recommendations and guidelines prepared by the Swedish Environmental Protection board (SNV), the emphases of current and future monitoring programs have changed. However, little attention has been focused on nonpoint sources of water pollution in considering alternative designs. This is important because monitoring programs to detect the respective impacts from point […]

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The first water pipe from Kallebäck completed in 1787 consisted of bored up timber of aspen and pine. It had served for 104 years when it in 1891 was replaced by a new cast iron pipe. Cast iron have since then been the dominating material of the pipes. Nowadays pipes with inside corrosion isolation of […]

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A master plan for sewerage in Gothenburg has been developed. The Water and Sewage Works serves 30,000 inhabitants in a 140 km2 area. The sewers have a total length of 2,233 km. The first Gothenburg master plan for sewerage was adopted in 1866. Combined sewers were laid until 1957. Therafter separate storm sewers have been […]

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The network for distribution of water in Gothenburg amounts to 1,500 km pipes. About 60 % of the length has an average age of 50 years and is made of cast iron, 20 % is ductile iron and has an average age of 10 years. The waterlosses in 1985 were 26 % of the produced […]

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Any change in water flow rate in pipes, regardless of the rate or magnitude of change, requires that the water be accelerated or decelerated from its initial flow velocity. A force is required to change the velocity of he flow and this force occurs as a hydraulic pressure transient in the pipe. The most common […]

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The water network in Gothenburg has a length of 1,530 km and consists mainly of cast iron pipes. The pipes are up to 100 years old and the biggest diameters are 1,200 mm. To establish the need for reinvestments during the next 10 to 15 years, a master plan has been worked out, setting out […]

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Göteborg har alltsedan 1894 Göta älv som råvattentäkt. Detta har ständigt medfört kvalitetsproblem. Vattenreningen har fått anpassas efter förutsättningarna – utvecklingsarbetet måste vara målinriktat och resultera i en snabb förbättring av vattenkvalitén. Vattnet renas genom klorering, flockning, avsättning, filtrering genom aktiverat kol (activated carbon) samt desinfektion med klor och klordioxid. Vattnet efteralkaliniseras och natriumsilikatlösning tillsättes. […]

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