Rainfall Harvesting System Feasibility Study for Non-potable Usage in irelan

Rainfall Harvesting System Feasibility Study for Non-potable Usage in ireland

AUTHOR: KAROLINE MAGATTI ALDUINO

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Contents

Abstract        

1.        Introduction        

1.1.        Irish Water Legislation        

2.        Building a Rainfall Harvesting System        

2.2.        Rainfall Water Treatment and Reuse        

3.        Current Use        

4.        System Implementation        

5.        Consequences in Ireland        

6.        Policies to Incentive the System Adoption        

7.        Conclusion        

8.        References        

9.        Appendix        

9.1.        Questionnaire “A Rainy Day Helps You Work, Rest and Pay”        

9.2.        Questionnaire Results        

9.3.        Room Temperature at 10 and 11 a.m.        

Figure 1:  Example of a catchment surface - rooftop catchment system. Source: http://www.gdrc.org/uem/water/rainwater/introduction.html        

Figure 2: Example of a roof washer system and its devices. Source: http://www.solarhaven.org/WaterStorage.htm        

Figure 3: Design of a typical cistern. Source: https://optirtc.com/projects        

Figure 4: Breakdown of domestic water consumption per capita per day in Ireland in 2006, Modified. Source: (        

Figure 5: Mean Annual Rainfall in Ireland Over the Period 1981-2010 (Walsh, 2012) [9].        

Figure 6: Flood Hazard Mapping - Dublin County. All the warning signs (triangles with an exclamation mark) symbolize flood events (OPW, 2016). [10]        

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Abstract

The lack of potable water is among the main concerns of the humanity nowadays. For the countries with plenty of water resources, like Ireland, the high rainfall leads to recurring floods in urban areas and soil erosion and contamination in rural areas. Because of that, measures are being taken in order to reduce the water consumption and prevent problems caused by high rainfall. One component of these measures, to preserve water and attenuate water run-off at the same time, is the rainfall harvesting system. This study aims to analyse the feasibility of building a Rainfall Harvesting System and its application in large scale in Ireland.

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1. Introduction

The increasing demand for freshwater and the unconscious use of it is leading the world to water scarcity. [1] According to the International Water Management Institute, water withdrawals are predicted to increase by 50 percent by 2025 in developing countries, and 18 percent in developed countries. Because of that, one of the major challenges of the century is to stem the ongoing and coming freshwater extinction.

When the subject water comes up, the first thing that we think is drought, but the lack of water is not the only problem. While in some regions of the world the drought causes concern, there are others where the high rainfall is a huge problem. These two extreme water situations make the water management even harder to be done in large scales. That is why the water problem mitigation must be punctual and need to be applied in each region or country accordingly to the environmental conditions.

In Ireland, the abundance of water resources is consequence of its high precipitation patterns, with an average annual rainfall of approximately 1230 mm [2]. The excessive rainfall results in one of the main problems of urban areas in Ireland, the flood. However, the water consumption per capita per day in Ireland is one of the highest in Europe, besides, with the rapid growth of the population, the demand for freshwater has increased and this means too much money being spent in water treatment.

The solution for the water issue in Ireland can be the water itself. The use of rainwater harvesting can convert the threat into opportunity, in other words, the adoption of this system in a large scale could prevent urban areas from flooding and recycle the water. However, it is necessary some stimulus from authorities so this solution could truly be implemented all over the island and the flood problem could be tackled.

1. Irish Water Legislation

The history of Irish water legislation began in 1978, when Fianna Fáil (political party in the Republic of Ireland) abolished water charges. Since then, politicians had constantly changed the water charges system, creating controversy among the Irish population.

The recent event of this history, which brought anger in the Republic of Ireland, is when the Irish Water was incorporated as a semi-state company under the Water Services Act 2013 [4].

1. Building a Rainfall Harvesting System

There are several techniques currently used for collecting and storing rainfall, which can vary in complexity according to the resources available for this and the demand for water in each location. Although there are three major forms of collecting rainwater, which are: in situ rainwater harvesting, external water harvesting and domestic rainwater harvesting. In this study, the focus will be on the domestic rainwater harvesting systems.