The Middle East region is facing several types of water problems due to many factors such as climatic and economic conditions, lack of water resources, and poor water management. Water is one of the most important resources required for the sustenance of all creatures on earth. The water supply system of a country should satisfy all the water demands of its citizens. The water supply systems should ensure that the water distributed should meet the quality required for human beings.endif; ?>
Water resources in Oman are exposed to manmade and natural threats such as tropical cyclones which are common in Oman, and water losses or Non-Revenue Water (NRW) through pipes leaks and other reasons.
The water supply system in Oman is run by a government Public Authority for Electricity and Water (PAEW). The high values of water losses and NRW mean that large quantities of water are lost because of pipes bursting, overflow of reservoirs, and errors in the reading of the costumer meter, and data processing. The high level of water losses impacts the financial situation; the PAEW is losing revenue, and the cost of operating water systems in Oman is increasing. This issue needs the intervention of well-qualified and innovative engineers and technicians especially since the Non-Revenue Water in Oman is considerable. The PAEW found a number of problems in the water supply system in Muscat such as low coverage, low service levels, problems with hydraulic designs, high NRW, frequent pipeline bursts, problems with billing and collection of revenue, and faulty water meters. Wastage of water or NRW seems to be the main problem in Oman, and one of the major challenges in managing water utilities all over the world as well. This study focuses on Wilayat Al Seeb in Muscat Governorate as a case study. The study area consists of a number of existing, older towns primarily located along the coastal areas and in the North East of the Wilayat known as Al Khoud, Al Mawalleh and Al Hayl. Al Mabela is also an existing town that is located to the west of Wilayat Seeb. The area includes a light industrial estate occupied by small workshops and warehouses. A large percentage of the houses currently located within these towns have been provided with a fully reticulated water supply although there are houses that are supplied from tankers as well as some empty pockets within the existing areas that have the potential to be developed. The main source of water supply to the Wilayat is from the Barka desalination plant. At present, water from the Barka desalination plant is pumped east and supplies the Seeb reservoir compound and Mawalleh reservoir. Water is then pumped further east to supply the Sultan Qaboos University, Ministry of Defense, Wave and Airport reservoirs. Water conveyed from the Barka desalination plant to the Seeb reservoir is then mixed with water from the Western Wellfields. The water in Al Seeb area is distributed using three types of pipes, namely, Asbestos Cement (AC), Ductile Iron (DI), and High-Density Polyethylene (HDPE) pipes. Many of the pipes are damaged and in need of replacement. The diameters of the transmission pipelines range from 150- 800 mm and the total length of the pipe is 29 kilometers while that of the distribution pipelines range from 150- 800 mm with a total length of about 740 kilometers.
Data on water supplies, water consumption, system data, and cost data between the years 2010 to 2014 were collected from the PAEW and used with the American Water Works Association (AWWA) software for determining water losses for the water distribution networks of the project area (Al Seeb Wilayat).
Thus, the water losses including real and apparent losses, NRW, water balance, and financial indicators were estimated using this software. The real losses include the water leakage from the transmission main and water distribution pipelines, the leakage due to the overflow of water from the reservoirs and water tanks, and the leakages from houses and other connections. Water loss can be defined as any leakage after the production of water before reaching the consumers. The main reasons of real losses and leakage from different sources are the insufficient leakage control, the age of pipelines, and poor operation and maintenance. Additionally, unauthorized consumption, for example, theft or illegal connections, and the inaccuracies in water meters contribute their share to the problem of water loss. The current study estimates that the water loss in 2010 was approximately 40%, which is much higher than international standards. However, this value was reduced to 30 % in 2014, which might be due to the continuous efforts of the PAEW to improve the water supply system in Al Seeb area. The total annual cost of water losses between the years 2010 and 2014 is more than 9.0 million USD. The water balance for Al Seeb water network obtained from 2010 to 2014 indicated that around half of the water supplied in year 2010 was without revenue and considered as losses. The condition improved in the last two years (2013 and 2014) as evidenced by the increase in revenue to 63.8% in 2014. The value of apparent losses has been almost constant during the past five years (around 20%), which might be because of data handling errors related to the performance of billing and collection company, or to the customer metering inaccuracies and illegal connections. The unbilled authorized consumption may include items such as firefighting and training, flushing of mains and sewers, street cleaning, watering of municipal gardens, public fountains, and frost protection. The results of water auditing have shown that the percentage value of this authorized consumption during the years 2010 and 2014 is within 2.0% only. The results also show that besides the strategy proposed by the PAEW, there are six controlling factors that need to be considered to control water losses and NRW such as: speed and quality of repairs, renewal of the water network, leakage control, pressure management, public education program, and information system development. The control of these factors might cause further improvement of water losses and NRW problem control in the country. It is concluded that there is a strong need to establish a water management system, which will be able to develop best management practices to further minimize the problems of water losses and NRW amounts in compliance with international standards.