**1. Introduction**

Although more than 71% of Earth is covered in water, 97.5% of the earth's water is salt water and most of the remaining 2.5% is locked away as groundwater or in glaciers; yet with such a vast reserve of water body on Earth, humans depend on the tiny bit available as fresh water and there is a global shortage of water. According to the WHO, it is estimated that by 2025, more than half of the world population could be living in areas facing water scarcity due to formation of mega-cities and increasing world population, which is expected to reach ~9.7B by 2050, causing further stress on water globally. Although water scarcity is a universal phenomenon, this chapter is focused on the continent of Africa and more specifically the region of Northwest Africa also known as the Maghreb. The region includes Algeria, Libya, Mauritania, Morocco and Tunisia (**Figure 1**). The Maghreb countries are located in an arid to semiarid region. The climate is very diverse and varying with the season and region; generally, it is characterized by mild-wet winters and warm-dry summers. Also, the climate in the Maghreb is Saharian in the South part, oceanic in the western, and Mediterranean in the North part. Although, each country in Northwest Africa has its own individual water reserves, regional characteristics and water management history, in spite of Algeria, Morocco and Tunisia have several similarities. A lot of data exists on the models and projections of water scarcity and as per Water Resource

**Figure 1.** *Map of the Maghreb-Northwest Africa [1].*

Institute, a map of water scarcity is shown in **Figure 2**, with areas in red showing extreme stress.

The Maghreb is one of the most "water-stressed" regions because of combinations of several factors, viz. population growth, climate change and anthropogenic contamination (anthropogenic pollution on the ecosystem). Tunisia, Algeria, Morocco and Libya face demand for water that is higher than the amount of quality water availableper capita; water availability has fallen below 1000 m3 annually. These countries are all on the top 33 water-stressed countries in the world [3]. However, Mauritania is facing low to medium water stress in the region. In addition to water stress, one of the serious difficulties facing the Maghreb authorities are in the regime of water scarcity management. It is currently at a crisis level which needs a quick reaction from all stakeholders.

Instead, with the ever-increasing demand of water to satisfy human development across the world and particularly the Maghreb region, it is observed that the most people in the world could not use this essential natural resource effectively, in terms of use, conserve and repurpose, specifically for the best regional management of water resources. It is important for countries and regions to urgently tackle the critical problems presented by water scarcity, determine the root causes of it and articulate new strategies, techniques and good practices to ensure adequate water supply for the needs of growing population. This chapter aims to address the reasons for increasing water consumption and highlights the several strategic-planning water managements through the solutions, techniques and the best practices which the Maghreb region has adopted to address water scarcity.
