Application Form for the European Green Capital Award 2019

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1 8 Water management 8A. Present Situation Indicator Unit Year of data Domestic usage - Litres per capita per day 160 litres/capita/day 2015 Total Usage Litres per capita per day 255 litres/capita/day 2015 Water loss in pipelines, leakage management and network rehabilitation 31 % 2015 Water supply system The water supply system consists of two water treatment plants and four back-up plants, 18 elevated basins, 30 pump stations, 1600 km of public water pipes and 1600 km of private service pipes. Water consumption is declining Over the past 20 years, Oslo s population has increased while water consumption has declined (8D22, figure 8.1). One reason is that leaks have been identified and repaired more intensively. Over the last four years, leakage detection has been conducted using smart technology such as acoustic- and correlating gprs-loggers. Household consumption has been reduced from 200 litres/capita/day in 1995 to 160 litres/capita/day in 2015, and the water leakage has been halved since Total water production and consumption by businesses and the public sector is measured by meters, while the household usage is approximated, based on actual figures and surveys. 1

2 Figure 8.1: The figure shows that total water production in Oslo is declining despite annual population growth. Households and businesses consume 58 % of the water supplied, 8 % represents unregistered public use and frost tapping, 3 % are sold to neighbour municipalities, while 31 % are leaks. Oslo s net number of daily commuters ( persons) and tourist overnight stays (approx a year) are mainly represented in the category Industrial and commercial consumption (see figure 8.1). All public sector activities and business subscribers are required to have meters All water consumption by public and private institutions and businesses is measured and invoiced by use of water meters. Close to 100 % of these subscribers follow the requirement. Installation of meters in private households is voluntary and consumption is mainly calculated using the area-size of the household. Oslo s drinking water is sourced from protected forests The drinking water supplied to the inhabitants of Oslo originates from surface water (see figure 8.2). The catchments are parts of the Oslo River Basin Area (8D1). Lake Maridal is the main water source, serving 90 % of the population. There are strict regulations on land use within the area of catchment % of the inhabitants in Oslo receive water from municipal supplies while only 0.2 % have their own water supply, such as wells, controlled by the municipality. 2

3 Figure 8.2: The map indicates Oslo s drinking water sources, including areas of catchment and water treatment plants, as well as the main waterways within the built-up zone. Ample supply of clean and fresh tasting drinking water The water sources, and their catchments, are continuously monitored and regulated to ensure adequate supply and quality. Water quality is maintained according to physical, chemical and microbiological parameters. As of 2015, all drinking water supplied, when operational conditions are normal, is in line with The Norwegian Drinking Water regulations (8D2). Oslo has no days of noncompliance with the EU Drinking Water Directive. 3

4 Leakage halved compared to 1995 In the past few years, the City has focused on maintaining and restoring the water pipe network. Leakage has thus been halved since 1995 (figure 8.3), and was estimated at 31 % in The minimum acceptable renewal rate of pipes is set to 1 % a year (8D10). Figure 8.3: Water savings due to less leakage. The blue bar shows aggregated number of saved leaks and red bar showing number of saved leaks a year as a result of measures implemented in accordance with the renovation plan. Local storm water management As a result of climate change and urban densification, local storm water management is the key to solve flooding and discharge problems. All new developments have to comply with local storm water management requirements and sewer inflow restrictions (8D3). Oslo is also working systematically to reopen waterways to reduce vulnerability to urban flooding (see indicator 4). The water-energy nexus In the water basin situated upstream to the main water treatment plant (Oset WTP), a hydropower station produces electricity before the water enters Lake Maridal. In the city centre, one elevated basin is equipped with two generators producing electricity (250 MW/h), as a pilot project. Output from these two power stations is sent to Oslo s electrical supply grid. Electricity consumption for water produced is 0.33 kwh/m 3. For water transport, the electricity consumption amounts to 0.12 kwh/m 3. In 2013, both Oset and Skullerud WTP started an optimization program to reach designed capacity with co-focus on reduced consumption of chemicals and water for the cleaning process. So far 5-10 % less energy is needed for the water treatment process. Compliance with EU directives The City of Oslo complies with national water regulations, which are based on the EU Water Framework Directive (WFD). According to the EEA-agreement, Norway must achieve the WFD objective of good status by As of 2015, all water sources have been documented and the main water management measures have been identified (8D11). Measures to achieve the WFD objectives include recovering natural migration for fish in Oslo s urban waterways (figure 8.4). 4

5 Figure 8.4: This culvert in the river Hoffselven used to be a barrier for migrating sea trout, but improvements conducted during winter 2016 as shown in the picture to the left, have been successful. The natural spawning area for sea trout is thus now re-established in accordance with the EU WFD. Collaboration with NGOs In Oslo, several NGOs are working ideally for conservation and protection of natural areas and waterways. Oslo River Forum (8D24) is an important collaborator for the City of Oslo, consisting of sub groups for each of Oslo s main waterways. Oslo River Forum works both as a consultation partner in connection with projects regarding reopening of waterways, facilitator for river adoption by elementary schools and as a watchdog (figure 8.5). 5

6 Figure 8.5: Agree! Representatives from Oslo River Forum, Schools in Oslo, Agency for Urban Environment and Mayor Marianne Borgen after signing a river adoption agreement. Photo: Fredrik Eckhoff 6

7 8B. Past Performance New water treatment plant and elevated basin Since 2009 the two WTP plants with hygienic barriers (coagulation/filtration and UV radiation) that comply with requirements set in the EU Drinking Water Regulations, have provided Oslo with high quality drinking water. In addition, a new elevated reservoir, Vettakollen, was commissioned in 2015, contributing to more safe and stable water supply in the western parts of the city. The effect of the renovation plan The main water network is subject to continuous renovation, based on the new Water Mains Rehabilitation Plan (8D4). The renovation rate has been ramped up in the later years and the leakage detection has improved in both capacity and quantity. Oslo s goal is to increase the renovation rate from 1 % to 1.2 % annually. Improved leakage detection In the past decade, Oslo s population has increased by 110,000 people. Despite population growth and challenges caused by freezing temperatures from October to March, with ground frost down to 2 meters depth, the annual water production has remained relatively stable, due to intense renovation, leakage detection and remote monitoring. Active use of data from the remote control system and evaluation of water consumption in selected areas of the city has provided more accurate information to be used in the search for leaks. The Breivoll Inspection Technologies (BIT) project (8D5) has developed a pipe scanner with technology from the Norwegian oil sector. The pipe scanner measures remaining pipe wall thickness and detects corrosion both outside and inside cast iron water pipes. From 2013 to 2015, the pipe scanners technology has been developed from scanning small pipes to scan pipes up to 600 mm in diameter. Asset replacement investments per property (figure 8.6) Figure 8.6: Comparison of investment in water infrastructure among participants in the European Benchmarking Cooperation Oslo VAV = Agency for Water and Waste Water Services. 7

8 Storm water management Oslo aims to manage storm water locally, preferably through nature based solutions. In 2011, the City developed guidelines on local storm water management for property developers. In 2016, a crosssectorial action plan (8D3) was adopted, identifying targets and measures to minimize storm water damages, comply with water regulations, as well as using storm water as a resource. A cross-sectorial action plan was finished in early 2016 and operationalizes the storm water strategy. The aim is to develop storm water systems with surface retention that reduces the load on the wastewater network. A 3D-model of the entire city was created and used for a surface runoff simulation which pinpointed some of the flood ways. The model gives a basis for theoretical drainage lines that have been analysed according to slope and catchment area of the lines to consider the probability for flooding and/or erosion (figure 8.7). Surface runoff and inundation depths for a storm event with a 200 year return period have been modeled for the urbanized area of Oslo. With these models Oslo will be able to target and prioritize mitigation and better determine the retention and floodway system. Figure 8.7: The map, from a chosen central area of Oslo, shows the risk of flooding for drainage lines based on depressions in the terrain and where the terrain is flat, categorized as low (green line), medium (yellow line) and high (red line) Oslo has ten main waterways running through urban areas (figure 8.8.). In the past five to ten years, efforts to reopen waterways have increased in order to manage storm water openly and locally. In the past decade a total of 2810 metres of waterways were reopened. Of this 1080 meters were reopened in 2015 and Plans include eco design with rapids, deep pools and recreational areas and a purification system that is managing runoff from heavily trafficked national roads passing Oslo (8D20). In 2016 the City s investment budget earmarked EUR 11.7 million for reopening projects (8D14). In addition, several green roofs and roof gardens, local rain gardens and storm water canals have been established to contribute to storm water management. 8

9 Figure 8.8: Map showing open and closed stretches of waterways within the built-up zone of Oslo. The map also displays the positioning of concluded reopening projects in the past decade, as well as ongoing and planned projects. Marka is the forest surrounding the City of Oslo (8D21). Classification of water quality in compliance with the EU Bathing Water Directive For years, the City of Oslo has monitored water quality in the city s waterways. Since 2008, recreational swimming areas by the fjord and waterways have been classified in line with the EU Bathing Water Directive s bacterial classification even though the directive has not been implemented in Norway (figure 8.9, see also 8D23). 9

10 Figure 8.9: Bathing water quality in recreational swimming areas in Oslo, categorized in line with the EU Bathing Water Directive. Comprehensive water quality monitoring The City has implemented a comprehensive monitoring programme. Drinking water and raw water quality, as well as water quality in lakes and waterways in the catchment area is monitored. Annually, approximately 1000 samples are collected, prioritizing microbiological parameters. Out of 750 routine samples of drinking water in 2015, only two anomalies were detected, in both cases resampling showed no anomalies. Water monitoring from the City s waterways include analyses of bottom-dwellers and fish (figure 8.14). Non-profit company The Agency for Water and Waste Water Services in Oslo is a non-profit agency. The entire budget for the agency is financed by water and sewage charges. Budget priorities come from the City Council. Water consumption is invoiced using a formula that multiplies the size of a residence (square meters) with the cost of production. Households can choose to be billed based on an approximation or request to have a meter installed. The commercial and public sectors are required to have meters. A clean Oslo Fjord In a clean-up operation between 2005 and 2011, 440,000 m 3 of contaminated sediments were dredged up from the port area and resulted in a cleaner seabed in Oslo s harbour basin. In the treated areas, % of contaminated sediments were removed. Results from bathing water test samples from the Oslo Fjord from the period , show that 63 % have excellent quality, 21 % good and 16 % sufficient. 10

11 Raising awareness H 2 OSLO Oslo actively encourages inhabitants to drink tap water, rather than bottled water that might have travelled great distances (figure 8.10). Reusable drinking water bottles have been handed out to school children in Oslo, as well as to people attending various festivals. A film about Oslo s water supply, targeting youth, has been produced (see 8D6). Water is valuable Through an Internet based water test, the inhabitants of Oslo can identify their water usage. The site also offers information on how to reduce water consumption (8D7). Facebook and Twitter are used actively to inform the people about measures to reduce water consumption. Figure 8.10: One of several posters from the 2015 campaign to help the inhabitants of Oslo to value the quality of and save drinking water. Text saying Your city, your water. 11

12 8C. Future Plans Oslo will ensure that management of drinking water supplies, waterways and ground water are ecofriendly, leading to a clean fjord (8D19). Strategies and targets are embedded in the Urban Ecology Programme (8D8). Oslo will maintain a strong focus on reducing household water consumption and leaks from the water pipe network, as well as local storm water management. Measures included in the Water Supply Master Plan state that the leakage rate by the end of 2018 shall be a maximum of 30 % and also that 1.2 % of the pipelines will be renewed. From 2018 future goals will be set for the leakage rate in order to decrease non-billed water. In conjunction with this goal, Oslo has implemented the ambitious target that the sum of water leaks and consumption shall not exceed 100 mill m 3 /year from 2015 to 2030 (8D10). 100 mill m 3 was the total water production in Reduction of water consumption 1. Improve leakage detection tools and continue current rehabilitation rate New methods for water leakage detection, such as acoustic loggers, active use of data from the remote control system and evaluation of water consumption in selected urban areas, are expected to provide valuable information in the search for leaks. In 2016 the budget for water pipe rehabilitation is EUR 20 million. Oslo will continue to renew and maintain the main water network, in line with the Water Network Rehabilitation Plan (8D4) and Water Supply Master Plan In the long-term budget ( ), the City Government has allocated EUR 77 million for renewal of the drinking water network and EUR 31 million for continuance of re-opening - and further increase - of the ecological status in Oslo s waterways. In order to achieve comparability with peers, IWA s water balance and EU Reference document Good Practices on Leakage Management will be the methodology used for the water balance account (8D9). s 2. Introduction of water meters The City of Oslo wants to increase the number of private subscribers who install water meters. EUR 217,000 has been allocated for a pre-pilot project, where meters will be installed in a selected part of Oslo in The goal is to decrease daily consumption per capita to 130 litres by Increased water supply reliability Risk and vulnerability assessments have identified that Oslo is facing challenges concerning reliability of drinking water supplies. To ensure ample access to safe drinking water at all times, the City conducted a concept study (CS) New Water Supply System in Oslo (8D12). The aim was to analyse what measures are necessary to ensure robust water supply, particularly when it comes to safety, stricter quality requirements and back-up supplies. 25 partial reports, ranging from hydrology to reinforcement of mains, from specific consumption statistics to consumption forecasts, have been developed. The CS provides valuable knowledge to the administration that will break it down into smaller projects, based on a risk evaluation for each measure. The CS will be politically debated in Focus on sustainable storm water management The action plan for storm water management (8D3) demands broad cooperation across municipal agencies to adapt flood-prone areas to handle more rainfall through reopening waterways (8D20, figures 8.11 & 8.12), and developing storm water infiltration (figure 8.13). This will improve the natural 12

13 water balance in areas where ground conditions are difficult. Reopening waterways is important in this context and is given a high priority in Oslo (8D13). Equally, there is a need for a pilot project on water runoff management from roads. City agencies cooperate with other public agencies, the private sector and NGOs in storm water management. Figure 8.11: Schematic outline for storm water handling by 3-step approach. Light rain infiltration. Medium rain collect and retain. Heavy rain secure flood ways (8D3). Figure 8.12: Teglverksdammen is a large scale reopening of the stream Hovinbekken (8D20). 13

14 Figure 8.13: Rain garden established in a park in north-eastern Oslo. During heavy rainfall, local storm water is led to this area, and thus helping prevent downstream areas from flooding. A new plan towards 2030 The Water Supply Master Plan, was adopted in 2015 (8D10). The planning process rests on two pillars: 1. Oslo must identify the most efficient measures to reduce water consumption and leaks in water mains, and include them in the plan. Introduction of water meters for all subscribers is a likely measure. 2. Oslo must ensure safe water supplies. The population is expected to increase from todays , to nearly by The target is to counter this growth by reducing specific water consumption and thus avoid a considerable increase in total consumption. Impacts of climate change will be taken into account in the plans. The River Basin Management Plan (RBMP) was passed in 2016 The RBMP is part of the WFD. Several hundred measures have been identified in order to achieve the WFD objective of good status by 2021 (8D11). 14

15 Figure 8.14: To increase knowledge about impacts from runoff road water, local trout from the river Frognerelva is examined for content of trace metals and persistent organic pollutants. No-dig Trenchless house connections to main water lines Oslo, in cooperation with Norwegian Water and WssTP, invited suppliers and researchers to find a method to connect service pipes to main water lines without digging trenches (see figure 8.15). The pilot project ends in December 2016 (8D18). Figure 8.15: Robot connecting main water pipe to service pipe. 15

16 8D. References PLANS & PROGRAMMES CONCERNING WATER MANAGEMENT, REFERENCED IN THE TEXT 1. Oslo River Basin Area (Norwegian) 2. The Norwegian Drinking Water Regulations (Norwegian) 3. Action Plan for Storm Water Management in the City of Oslo (English) Executive summary 4. Water Mains Rehabilitation Plan, (Norwegian) 5. Breivoll Inspection Technology (English) Information about the methods used for scanning water pipes. 6. Film about Oslo s water supply (Norwegian) 7. The Water Test (Norwegian) Public information campaign to raise awareness about water consumption. There is also an App for mobile phones and tablets. 8. Urban Ecology Programme (Norwegian) The environmental policy of Oslo passed by the City Council. Section 5.3 and 5.4 outlines priorities, targets, strategies and measures on water management. 9. EU Reference document Good Practices on Leakage Management (English) 10. The Water Supply Master Plan, (Norwegian) 11. The River Basin Management Plan (Norwegian) The Ministry Climate and Environment s approval of the regional plan for water management in the River Basin Districts. 12. New Water Supply System in Oslo (Norwegian) Concept study exempt from public 13. Principles for reopening of streams and rivers in Oslo (Norwegian) 14. The Municipal Budget 2016 and Economic Plan (Norwegian) OTHER PLANS & PROGRAMMES CONCERNING WATER MANAGEMENT 15. Action Plan for the Environment and Climate (Norwegian) The City Council s priorities based on passed strategies and measures, to ensure that the environmental policy is implemented 16. The 2015 Municipal Master Plan, Oslo towards 2030 (Norwegian) Smart, Resilient and Green 17. Water Statistics in Norway, data from Statistics Norway (Norwegian) National statistics on water supplies, average water usage, renewal of water pipes, percentage inhabitants with adequate drinking water quality and operating expenses. 16

17 WEBSITES 18. No dig for service pipes, tender documents (English) 19. Good Practice 5 in the Application: The Fjord City (English) 20. Good Practice 6 in the Application: Reopening waterways in Oslo (English) 21. Best Practices in The City of Oslo: The protection of Marka (English) 22. Best Practices in The City of Oslo: Decrease in water consumption (English) 23. Best Practices in The City of Oslo: Bathing water quality achieved in the city harbour basin (English) 24. Oslo River Forum (Norwegian). Oslo River Forum is a NGO working for protection and rehabilitation of waterways in Oslo in close collaboration with the City s agencies. 17