Abstract:
Water distribution network (WDN) is the components of water supply system that needs to
design carefully because of cost involved and its significance. However, in many of the
developing countries, the hydraulic and physical performance of water distribution network
is inadequate to meet consumers’ demands and losses in system. Addis Zemen has been
experiencing frequent and regular disruption of water supplies for days to a week. This study
was conducted in Addis Zemen, to evaluate hydraulic performance of existing water supply
distribution system of the town. Both primary and secondary data sources were used in this
study. Primary data were collected though face-to-face interview with Addis Zemen Water
Supply and Sewerage enterprise (AZWSSE) experts, field observations, photographs of
relevant sites and infrastructures were taken. For secondary data collection, document
review was used to collect valuable information. To analyze the data which is collected from
different sources, both qualitative and quantitative methods was used. The computer software
application that is Origin8 and excel was used to analyze the data obtained from office. The
field survey data for distribution system was evaluated by using the engineering software
called WaterCADv8i. The per capita domestic water consumption of Addis Zemen Town was
found to be 12.98 l/c/d in the year 2015. The average water loss in Addis Zemen Town was
25.6%, showing that needs a matter of concern. 11.6% of the junctions were (>70 m) located
around Michael area and Hospital due to low elevation. 1.9% of the junction was (<15 m)
recorded 14 m around Hana due to high elevation.86.5% of the town that is the majority of
the area has pressure within the optimum range (15-70 m) and the lowest velocity recorded
was zero and the highest was 2.12 m/s during steady state analysis. 13.5% of the analyzed
nodes get water at low pressure (<15 m), none of the node has pressure above 70m and only
86.5% have pressure within recommended limit (15 to 70 m) and velocity in major pipe parts
was below 0.6 m/s during extended period simulation. The current water demand is 1398.68
m
3
/day and the demand at end of design period of 2025 years would be around 2926.33
m
3
/day. In order to achieve a 15 m minimum and 70 m maximum pressure, it is necessary to
provide pressure controlling valve and establishing boosting station. Securing additional
water supplies becomes an essential issue to meet the current water demand future demand
