IVAR's Object Is to Build and Operate Joint Municipal Treatment Plants for Water, Sewerage and Solid Waste
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IVAR's object is to build and operate joint municipal treatment plants for water, sewerage and solid waste. The company's vision is to ensure that the region benefits from the market's most competitive services. IVAR is at work 24 hours a day Owned by eleven municipalities IVAR is owned by the following municipalities: Finnøy, Gjesdal, Hå, Klepp, Kvitsøy, Randaberg, Rennesøy, Sandnes, Sola, Stavanger and Time. Together, these municipalities have approximately a quarter million inhabitants. This region is one of the most active in the country in terms of the economy and demographic trends. Development of the technical infrastructure is a key prerequisite for this activity. A total of 84 IVAR employees were responsible for a turnover of approximately NOK 280 million in 2003. A challenging future IVAR has achieved exellent results. However, IVAR is facing demands of increasing the efficiency within the scope of handling wastewater, water and solid waste. Our response to these challenges is to further develop the regional cooperation, both in width and in depth. The goal is to ensure that regional objectives and a long-term perspective continue to play a key role in our industry. Organisation chart Supervisory board IVAR's facilities Water main Board of directors Raw water tunnel Municipal borders Managing director Wastewater main Marketing and Planning/ Finance/ Operations development construction Administration Sources and Transport Wastewater General water treatment facilities Landfills Composting treatment maintenance 3 The best drinking water comes from your tap Our drinking water is subject to the most stringent requirements for hygienic water quality – a quality you can taste! IVAR supplies the entire Jæren region with the highest quality drinking water. Plenty of water - good water Water is the most important element of our nutrition. Drinking water is basic for all human activity. Traditionally, we have had good access to water in Norway, and we have developed a culture in which plenty of pure, clean water for everyone is taken for granted. IVAR's responsibility for water sources, water treat- ment and transport to the respective municipalities requires huge investments and reliable technical solutions. Distribution to the consumers takes place through the municipal water distribution system. Sources for drinking water The primary sources for water supply to the Jæren region are located in the municipalities of Bjerkreim, Gjesdal and Hå. Stringent environmental demands apply to the water source areas. Governmental restrictions on farming and traffic ensure the raw water quality. A small power plant has been built into the tunnel from Stølsvatn lake to exploit the downward gradient of the water flow from source to water treatment plant. The water treatment plants are located at Langevatn lake in Gjesdal municipality and in Matningsdal in Hå municipality. The water quality at the sources has low water hardness. The water has low colour index and low contents of humus and nutrients. IVAR perform analysis (limnology) of the water sources regularly. The highest requirement for water quality The Langevatn water treatment plant has the capacity to treat 2500 litres of water per second. CO2 is added to the water upstream the marble filters to increase release of lime from the marble. As a nutrient, drinking water is subject to stringent quality requirements. All water delivered from Langevatn is passed through alkaline filter material and disinfected. Both the process and water quality are continuously controlled and assured. An absolute requirement for all drinking water is that it must be hygienically safe. Good drinking water is without noticeable smell, taste and colour. The Langevatn water treatment plant supplies drinking water to nearly a quarter million people. 30-km water main IVAR's water supply system consists of three main components: Transport facility for raw water, the Langevatn and Matningsdal water treatment plants and the transport system for drinking water. The new water main extends approximately 30 km from Langevatn lake to Tjensvoll. The water main has a diameter of 1400 and 1200 mm. Valve chambers have been established along the main, allowing the water to be shut off or diverted, and this is where the municipalities have their distrubution points. IVAR's water mains are designed and engineered Orstad valve chamber. to safely transport water for at least 100 years. 5 We treat wastewater – for a sustainable environment IVAR receives and treats about 90 % of all and industry in the municipalities of Randaberg, wastewater from the joint municipalities. Stavanger, Sola, Sandnes and Gjesdal. Our goal is to ensure that discharges of The design capacity is equal to a total number of wastewater do not harm rivers or the sea. inhabitants and population equivalents (PE) of appro- ximately 240 000. The plant is located at Mekjarvik in Treating wastewater – for the Randaberg. The wastewater treatment facilities are located benefit of the environment in rock while the sludge treatment, administration In the areas along the coastline in the southern point building and workshop facilities are located outside the of Norway, focus has traditionally been on removal of rock. The plant was put in operation in March 1992. phosphorus and particles in the wastewater. Most of the The plant comprises an 8-km inlet tunnel from major wastewater treatment plants along the coastline Bjergsted in Stavanger, as well as a 4-km outlet tunnel – including IVAR's plant in Randaberg – are therefore to Håsteinfjorden with discharge at a water depth of based on chemical precipitation (primary precipitation). 80 metres, 1.2 km offshore. Norway is obliged through the EEA Agreement to The plant is constructed as a primary precipitation comply with the treatment requirements in the 1991 plant where the wastewater is mechanically pretreated in Urban Waste Water Directive. IVAR's goal is to accomplish screens and aerated grit chambers. Chemicals are induced this, using costeffective and environmentally beneficial to initiate precipitation. Produced particles are deposited solutions. in sedimentation tanks. Two separate trains ensure a high level of operational flexibility. SNJ – one of Norway's largest wastewater treatment plants Produced pellets used for The Regional Wastewater Treatment Plant of Nord-Jæren soil improvement (SNJ) receives and treats wastewater from residentials One of Norway's national objectives is to ensure that as much as possible of the nutrient content in the sludge generated at the wastewater treatment plants, can be returned to the soil. The sludge from the sedimentation tanks consists of 95 % water, which means that the dried solids content amounts to just 5 %. The solids content after centrifugal dewatering and thermal drying is about 85 %. The dried product is formed into small pellets (biopellets) that are simple to store, handle and transport. The final product is pathogenfree and meet the governmental standards for recycling. 35-km main sewer The wastewater is transported from Gjesdal in south via Sandnes and Stavanger to the wastewater treatment plant in Randaberg. The transport system consists of gravity flow lines, pumping stations with associated pump lines and tunnels. The inlet tunnel from Bjergsted in Stavanger has a diameter of 3.5 metres. The tunnel has a volume of 77 000 m3 and functions as a equalization resorvoir. Additional wastewater treatment plants The Vik wastewater treatment plant, which receives and treats wastewater from Time and Klepp municipalities, is a biological plant. Phosphorus and organic substances are removed from the wastewater in an activated sludge process – bacteria do the job of cleaning the wastewater. The Oltedal wastewater treatment plant receives wastewater from the residents of Oltedal and process water from industrial activities in the area. This plant is a combined biological and chemical plant. The Bore wastewater treatment plant receives wastewater from the residents of Klepp municipality and industry. The plant performes mechanical treatment in sieves, and is designed for 20 000 equivalents (PE). The same applies to the Sirevåg wastewater treatment plant, which receives and treats wastewater from residents and industrial activities in the Ogna and Sirevåg areas. The plant’s designed capacity is 15 000 PE. The sludge from Vik and Oltedal plants is transported to SNJ in Mekjarvik. Process control IVAR's different plants are distributed over a large geographic area. Several of the plants have relatively complicated processes. Computer-based control and monitoring systems are applied for safe and efficient operation. 1. Sedimentation basin, SNJ 2. Regional Wastewater Treatment Plant, Nord-Jæren 3. Biopellets 4. Vik Wastewater Treatment Plant 5. Sentral control room at SNJ We transform your refuse into valuable resources IVAR receives and processes solid waste from municipalities' waste disposal services. IVAR works with a number of private and public organisations with the objective of ensuring improved exploitation of solid waste. Less waste to landfills – more to recycling For many years, the Sele landfill was the largest facility of its kind in Norway. In 1997 we received nearly 140 000 tonnes of waste at the landfill. As a consequence of our work to exploit our resources better, we now see that the volume of residual waste ending up at the landfill has been substantially reduced. In 2004 we expect to receive of about 30 000 tonnes of residual waste. The recycling rate