Performance Evaluation and Sustainability of a Water Distribution Network

Assignment Brief

CIVE 4307 Individual Project

You company has designed a small water distribution network for a new town to house workers near Ottawa. The source water includes a fresh water lake approximately 4 km long, 1 km wide, and has an average depth of 10 m. The water balance of the lake is naturally zero when the average net precipitation is 0.5 mm a day. Ministry of the Environmental officials mandate that the lake level cannot be reduced below 9.9 m average depth. A pump is used to take water from the source to the network. In addition, an elevated water tank is used to help providing water to the system.

Your company has used EPANET and built a model (posted on cuLearn) for the water distribution network. You are tasked to check:

• The performance of the distribution system (e.g. pressure at nodes, velocity of pipes).
• The analysis of pump and tank and how they work together to meet the daily demand.
• The water level change in the lake. Use annual average precipitation for Ottawa in your analysis. Please submit an electronic copy.

Sample Answer

Performance Evaluation and Sustainability of a Water Distribution Network for a New Town near Ottawa

Introduction

This report presents a detailed evaluation of a small water distribution network designed to supply a new town near Ottawa. The network utilises a freshwater lake as the primary source, which measures approximately four kilometres in length, one kilometre in width, and an average depth of ten metres. Water is delivered to the town through a pump, complemented by an elevated tank that ensures consistent supply and pressure. The Ministry of the Environment has stipulated that the lake level must not fall below an average depth of 9.9 metres. This study assesses the hydraulic performance of the network, examines how the pump and tank function together to meet daily water demand, and evaluates the impact of water abstraction on the lake level using annual average precipitation data for Ottawa.

Project Objectives

The primary aim of this project is to ensure that the water distribution system operates efficiently while maintaining sustainable water levels in the lake. The specific objectives include assessing node pressures and pipe velocities to verify system performance, evaluating the coordination between the pump and the elevated tank in delivering water to the town, and calculating the potential changes in the lake’s water level to ensure compliance with environmental regulations. This approach allows for a comprehensive understanding of both the operational and environmental aspects of the network.

Project Scope

The scope of this analysis is restricted to the proposed water distribution network, the lake as the water source, the pump, and the elevated tank. Other potential water sources, alternative network configurations, and external factors such as additional municipal infrastructure are not considered in this report. The hydraulic performance analysis is based on the EPANET model provided, which simulates flow, pressure, and tank behaviour within the network under normal operating conditions.

Literature Review

Water distribution networks play a critical role in ensuring reliable access to potable water, which is essential for public health and urban development. Previous research highlights the importance of maintaining appropriate node pressures and pipe velocities to prevent damage, water loss, and service interruptions. Elevated tanks and pumping stations are commonly used together to balance supply and demand. The elevated tank stores water during periods of low demand and releases it during peak usage, which reduces the operational burden on pumps and maintains consistent pressure throughout the network. EPANET is a well-established tool for modelling water distribution systems, allowing engineers to predict hydraulic performance and identify potential inefficiencies. Studies also show that monitoring lake levels and integrating average precipitation data into water balance calculations are critical for sustainable water management, particularly in regions with variable rainfall patterns.

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