Design of Water Distribution System for Araromi Community, Ondo State Using EPANET

— It is crucial to supply an adequate and consistent amount of water through the planned network of pipes in order to satisfy the water needs of the constantly increasing population. This research covered the design process for the water supply system for Araromi in Ondo state, Nigeria. With the aid of the program EPANET, the area's water supply plan was simulated. Due to the unavailability of concise data about Araromi as at the time of this study, this research projected a population of 1400 persons, assumed a water demand of 300 liters/person/day, and supplied an overhead tank of 17,500liters with an 8-hour maximum supply. This study provides other researchers with a foundation to build future research in Araromi Ondo State, Nigeria.


II. METHODOLOGY
A. Study Area The water distribution system was designed for Araromi, which is situated in Akure, the state capital of Ondo Nigeria. Akure is located between the latitudes of 7013'N and 7017'N, and the longitudes of 507'E and 5014'E [4].
The geographical location and elevation profile of Araromi were displayed using Google Earth Pro software as shown in Fig. 1. The geographical location obtained from the google earth software was then imported as the backdrop to the EPANET 2.0 interface and developed into the network as shown in Fig. 2 and Fig. 3.

B. Population Projection
The population was projected using Equation (1).
Where; Pi is the initial population, r is the annual growth rate, n is the number of years, Pt is the Projected population [5].

C. Water Distribution Design
There is no well-established water distribution design guideline or standard governing the study area. This research assumes water demand for Araromi to be at 300 liters/person/day. This is based on EPANET 2.0 design guide for hydraulic solver software used in the simulation [6]. Other assumptions made for this design were the number of houses = 200 and an average number of members per house = 7, which gave a total population of 1400. The required water demand in a particular junction was determined using Equation (2) put forward by [7].
Dt is the Total demand in L/day, Dp is Demand per person L/day, P is Population, Bd is Base Demand L/s, Nj is the Number of Pipe Junctions The peak flow for the design of the distribution system was gotten by multiplying the maximum hourly demand by a factor of 1.5.
The hydraulic theory of water distribution in pipes is the basis of the EPANET 2.0 software [8]. The mathematical model used in this design is Hazen-Williams' equation, with the coefficient of the roughness of pipe, C as 100.

D. Parameter Validation
The velocity parameter was validated using Equation (3).
Where; V is the velocity of flow across pipe length (m) Q is the discharge or rate of flow through the pipe length (m3/s) D is the diameter of the pipe length (m)

E. Design Standards
The design standards for EPANET 2.0 used for this design were provided by [9], as shown in Table I.

III. RESULTS AND DISCUSSION
The results of the junction simulation using EPANET 2.0 is shown in Table II.
The simulation's input is the demand as well as the elevation of the various junction. The simulation was used to create the network and pressure head.
The values for velocity, flow, and head-loss as generated from EPANAET 2.0 were within the design guide range (Table III). For velocity, the results generated were within the range of 0.3 to 1.0 m/s. This is a tolerable range for pipe diameter of 100-300 mm (which describes the size of pipes used for this design).  Also, the results generated for the head loss fell within the range of 0.1 to 3.0 m/km. This value falls within the tolerance range for pipe diameter of 100-300 mm (which describes the size of pipes used for this design).
The results obtained from the research are shown in Fig.  4-Fig. 6.

IV. CONCLUSION
With the aid of EPANET, the water distribution system in this work was designed. The method of distribution used is a combined gravity and pumping system, in which the water is first pumped from an underground water source and then lifted up to the overhead water tanks, where it is then transferred to the main rising pipe by gravity and the loop system is the distribution system employed. The storage tank used in this study has a capacity of 17,500 liters. Since there is a higher demand for water during peak hours than at other times, the maximum supply is provided for 8 hours each day.