1 Introduction
Privately owned domestic wells (Figure 1) provide water to hundreds of millions of people around the world. They are the most common type of water supply used in rural areas where public water supplies are not available. Because they are privately owned, and often located in sparsely populated areas, they are difficult to monitor and protect. Domestic wells are largely unregulated, except for their initial construction, and it is the responsibility of the well owner to maintain their well and ensure the water is safe to drink. Although many domestic well owners do an excellent job managing their wells, many others do not have the resources to protect their well or regularly test their water quality. As a result, domestic wells are the most common way for people to be exposed to groundwater contaminants. Despite these risks, the majority of domestic wells provide safe and reliable water supplies. Where public water supplies are not available, domestic wells are usually the best water supply option, as long as they are properly constructed, located away from contaminant sources, and regularly maintained and monitored.
Figure 1 – A domestic well providing water to a private household (modified from USEPA, 2019).
This book provides an introduction to domestic wells, including their construction, regulation, vulnerability, protection, and the valuable data they can provide for groundwater research. It is part of a series of books on domestic wells, each of which provide greater detail on the domestic well topics that are covered at an introductory level here. This book focuses on domestic wells in Canada and the United States, although some information from other countries is presented. For information about domestic wells in other areas of the world, including Africa, Asia, and Latin America, The Rural Water Supply Network is an excellent resource.
This book is primarily written for students, groundwater professionals, and policy makers with a background in water science and a professional interest in domestic wells. Questions that are discussed here include: How many people use domestic wells? How much does domestic well contamination contribute to disease and health care costs? How can the safety of domestic wells be improved? How can we ensure the water quality and quantity of domestic wells remain sustainable?
Throughout this book, the term “domestic well” is used to refer to wells that are privately owned by individuals and used to provide water for domestic purposes (i.e., water for household needs such as drinking, cooking, bathing, and cleaning). A domestic well typically serves a single household or sometimes a few households at a time. Domestic wells are also commonly called private wells or residential wells. For regulatory purposes, domestic wells are often distinguished from public wells based on the ownership of the well (i.e., privately owned by a homeowner versus government owned) or the number of people served by the well. In the United States for example, public water systems are defined as supplies that serve an average of at least 25 people for at least 60 days a year or have at least 15 service connections. Wells that serve less than these thresholds are defined as private water systems.