General Overview of the Study Area
The study area is found in Tigray region, central zone, which is situated about 1025 km north of Addis Ababa. It is located on UTM coordinates between 1547650-156700 N and 458000- 480000E, Including Aksum town and its surrounding areas with a total area of 425. 7 sq km. according to the 2007 national census conducted by the Central Statistical Agency of Ethiopia (CSA), the population of Aksum town was 49523 and according to population projection of 2015, Aksum town has a total population of 66800 .Aksum town is located on the narrow ridge that forms the divide between two major drainage systems, Tekeze River south of Aksum town and Mereb River north of the Aksum town.
The town is an important historical center and tourist attraction. According to historical evidences, Aksum is amongst the ancient and historical towns of Ethiopia. Different historical studies indicate that, Axum was the seat of Ethiopian kings and since 4370 BC; the civilization was particularly dynamic during the reign of Queen of Sheba. From about 1000BC until the birth of Christ about 98 kings and during Christian times that is from Abraha we Atsbaha until 922 AD, 58 kings governed. During this long historical period Aksum greatly contributed to human development. The stone stale, the rock tombs, the temples, the palaces, the stone thrones and sculptured stone monuments are some of the ancient evidences to its contribution. In 1980, UNESCO added Axum\'s archaeological sites to its list of World Heritage Sites due to their historic value (Empire 2020). Figure3. 1: Location of case study area
The town is situated very near a divide between the watersheds draining to the north and those draining to the south. In fact a seasonal stream that drains the town area rises in the town itself and flows to the southeast. This and another stream draining to the southeast both form the broad valleys and plains in the fringes of the town to the south .The town is surrounded by mountains and hills in the north, east and west directions. Therefore this topographical feature of the town makes to have different elevation zones that govern the location of the reservoir. The higher elevation the lower water supply can get.\n
Aksum is situated on the northern part of the Ethiopian central plateau at an average elevation of about 2100m. According to the Ethiopian temperature zoning, Aksum lies on the Woina Dega zone. The warmest months are between April and June, inclusive with mean maximum temperatures generally between 28 and 30 0c and mean minimum temperatures between 13 and 15 0c. In the coldest months, which are between December and February inclusively, both the maximum and minimum temperatures are 3 to 5 0c lower than the warmest months. The monthly mean values usually range with in plus or minus 2 0c from the long term averages. Water distribution system of the town is affected by temperature variation. During The warmest period consumption of water is high and the design system must satisfy this condition.
A detailed master plan of Aksum town is prepared by urban development and planning department of the region. The town is expanding towards east where the airport is situated. The area is favorably located on a plain land which has good access to expand the town and access to road transport. Therefore the existing water supply distribution network design needs to expand to meet and balance the demand and supply of the town.
Education and health
Education and health institutions in Aksum town include university, private collages, elementary schools, secondary and preparatory schools and tertiary level institutions. There is one hospital which is also used as referral hospital for Adwa and Shire Endaselasie towns. It is well staffed with various health professionals ranging from mid-wife to surgeons and internists; however it has acute shortage of rooms, beds, medical equipment and necessary medicines and other utilities. The designed water distribution system must consider to those area but still accesses of water is very less in these educational and health centers. There is intermittent of water throughout the year.
Existing water supply of the town
The concept of water supply as water provision involves the whole processes beginning from water source up to consumption. It is mainly concerned with the supply of water intended for human consumption and the water quality that must be met physically, chemically and bacteriologically. It also includes sources, distribution coverage access as well as its adequacy and sustainability. The current predominant water source for Aksum town is ground water. German Water Engineering first designed the existing water supply system for Aksum town in 1973. Later, another additional well was drilled in 1992 which is 2 to 5 km southwest of Aksum town. However, the demand of the municipality was unmet by the wells drilled in 1992. Additional boreholes, funded by the Tigray Regional State, were drilled between 1998 and 2000.