Rainwater Harvesting: A Strategy For Reducing The Use Of Municipal Water

Abstract

Canadians, like most developed nations, enjoy unlimited access to high quality potable water pumped directly to their homes at a relatively low price. Although this may seem to be an ideal situation, the reality is that it is an unsustainable one, as the costs of operating the system are much greater than the user fees recovered, and fresh water supplies which were once thought to be abundant, are quickly becoming scarce. As a result there is a growing realization that there needs to be a change in the fundamental way in which water management is approached, that the supply side solution of simply expanding the centralized water distribution system is not the right path to take, and alternatives solutions, known as a ‘soft-path’ approaches are gaining in popularity. One such alternative is rainwater harvesting (RWH). The collection and storage of rainwater for human use, has been used throughout history for agricultural purposes, yet it has received little attention in modern society, mostly because the centralized water distribution system is so convenient and, a public work, inexpensive. However, increasing social trends of environmental consciousness and protection have led to the growing realization that freshwater is not an infinite resource, and that current rates of consumption and distribution methods are unsustainable. RWH is way of responding to this problem by reducing demand on the municipal infrastructure through the onsite collection and use of rainwater for normal domestic purposes. Only a small portion of the municipal water supply is drank, yet all of it is treated to the very high potable water standards at considerable expense. The vast majority of it is used for purposes which do not require potable water, such as flushing toilets or watering lawns, making the treatment process quite inefficient. This report will study the feasibility of Calgarians using rainwater to replace the non-potable uses of water in the home, and by doing so, how it could result in savings for the City through reduced demand on water infrastructure, while also benefiting the environment through reducing the amount of water withdrawn from the rivers while reducing the GHG emissions emitted by generating the electricity needed to power the system.