bering strait region of western alaska both the native village of savoonga, located on st. lawrence island, population 600, and the native village of saint michael located on norton sound, have been using vacuum sewer systems for years. selawik, renovated its vacuum sewer system in 2014, saving over $217 000 a year on energy costs. arid regions especially in the middle east (united arab emirates, qatar, bahrain, oman), vacuum sewer systems become more and more important due to easy and fast installation along with water saving effects and easiness of maintenance. palm island jumeirah, located at the coast of dubai city, united arab emirates, has low, flat terrain, with a high water table, a water protection area, a need to conserve freshwater, and a low population density. it has therefore installed a vacuum sewer system. approx. 23,000 people (or 2000 buildings) will be connected to this vacuum sewer system. the system has only one central vacuum station serving 40 km of sewer line. the vacuum station is considered to be the biggest vacuum station in the world. the eco-city of masdar, u.a.e., uses a vacuum sewer system as well to separate grey from black water. lately, vacuum sewer systems become popular for industrial and commercial projects as well, where only little domestic waste water occurs and where the flexibility of a vacuum sewer system allows easy coordination with usually plenty of other utilities in the ground. good examples can be found again in the middle east, such as some small industrial areas in the emirate of ras al khaimah or the newly built qatalum aluminium plant in qatar, the world's largest primary aluminium plant. vacuum sewer systems are not only used in the europe or middle east but even in low developed third world countries. several vacuum sewer systems have been already built or are currently under construction in africa (south africa, botswana, namibia) for townships and rural areas where the benefit of fast construction time, cost saving trenching and high flexibility have come to full effect. australia has been one of the largest users of vacuum sewer systems due to the low installation and operational costs. the largest system to-date has been at the tea gardens development in new south wales, which will ultimately handle over 4,500 houses. the water corporation in western australia is considered the largest single owner of vacuum systems in the world with over 30 schemes now under their operational control. high water table areas the united kingdom is well served by vacuum sewerage systems. the region most extensively served is the low lying fenlands of the east of england. high water tables (in some cases less than 1 metre below the surface) and poor ground conditions have meant that the local water company, anglian water, has embraced the use of vacuum sewerage, taking advantage of the system's requirement for small bore sewer pipes laid in shallow trenches, dramatically reducing the requirement for pumping stations as would be required by conventional gravity sewer systems. the largest vacuum sewerage scheme in this region serves the villages of outwell and upwell; four vacuum collection stations serve some 1500 homes in this agglomeration. on initial costings for a conventional gravity sewer to serve the area, previously served by domestic septic settlement tanks the site would have required the installation of 32 pumping stations. using a vacuum sewer system, this number of pumping stations was reduced to four vacuum stations. other companies in the uk such as southern water operate vacuum sewer systems, too. in northern germany, several hundred systems have been operating since the 1970s. more are planned. hamburg's 770-unit jenfelder au development was planned with vacuum sewers. the city of ocean shores, washington makes a good case for vacuum sewer reliability and endurance. the city's vacuum system is one of the largest in the world, and it is also mature; most of its components are more than 20 years old and must function in a challenging operational environment along with gravity sewer and grinder pump systems. the county of sarasota, florida and other localities in florida have adopted vacuum systems, in some cases as an anti-eutrophication measure. the city of carnation, washington is developing a collection system that incorporates vacuum sewers. good examples can be found on the maldives, the post-tsunami watsan project unicef - un, where on several islands vacuum sewer systems have been the best option. several other project, mainly for resorts, have already been realized on the maldives. provincetown, massachusetts, usa areas with seasonal freezing the biggest installation in europe (several vacuum stations) can be found in gerasdorf (near vienna), austria, where many benefits of a vacuum sewer system helped to overcome difficult conditions in this mountainous area. estonia has vacuum sewers. poland has vacuum sewers. ruling technical guidelines and norms en 16932-3:2018 drain and sewer systems outside buildings dwa-a 120-3 wef (water environment federation) alternative sewer systems (second edition -2008) wsa 07 (australian code) as 4310 - 2004 (australian vacuum interface valve standard)