Growing Blue - Water Stress Level Tool

There’s a tremendous amount of water on the earth, but for it to continue to be a reliable supply for future growth, it must be available to local populations in sufficient quantity and quality, and without compromising local ecosystems.

Unfortunately, this is not the case in most of the world, as water is unevenly distributed among the world’s population. Today more than one billion people lack access to safe, clean drinking water, and just 10 countries share 60 percent of the world’s natural, renewable water resources.

Keeping existing water supplies healthy and sustainable is therefore critically important. The red areas on the map above indicate areas that are already water stressed. Other colors show areas that are on the brink.

While the quantity of water on the earth is the same today as it has always been, less than one percent of this water is available for human use. The rest is frozen in polar ice caps or present in the ocean’s salty waters. The earth’s small portion of usable water is found in groundwater sources and in surface water, such as rivers, lakes and streams

There is a limit to the amount of water we can sustainably use – and today many water withdrawals are not sustainable. As this map shows, too often there is an imbalance between the water we withdraw from the ground and the water we return to the earth. Our water resource challenges can only be met if we adopt both short and long-term water resource management plans combined with appropriate governance.

Doing so is a shared responsibility, and it begins with better managing water withdrawals. Today, roughly 15 to 35 percent of irrigation withdrawals are estimated to be unsustainable – and this is true globally. In Europe alone, 60 percent of cities with more than 100,000 people are using groundwater sources faster than they can be replenished.

Current practices will not be able to meet growing population and rising energy demand, and as a result, fossil aquifers will no longer be a long-term, viable option. We simply won’t be able to recharge them quickly enough.

Communities that cannot guarantee a reliable supply of water create a business risk to companies looking to build and invest in locations with reliable water supplies. Abnormal rain events, the lack of proper storage infrastructure and climate change all contribute to fluctuations in the local water supply, which can create uncertainty if not properly managed.

The map above shows the prevalence of abnormal rain events around the world, giving an estimate of the relative deficit or surplus precipitation over a 12 month time period. These types of events contribute to the natural variability of water, both year-to-year and within a single year. For example, the average amount of water available per person in some areas of the Middle East varies from less than 1,700 cubic feet per year, to over 3.5 million in humid, sparsely populated portions of the region. Climate change will only exacerbate these dramatic swings. In fact, current temperature, weather, sea level and water variability projections suggest that the next 30 to 50 years will bring substantial population displacements as a result.

Polluted water impedes growth in a number of ways. First, it impacts public health, constricting human development and ultimately, GDP. Second, polluted water impacts the agricultural sector we rely on to feed the population. Third, it limits the available water necessary to support business and industry. Lastly, the water cycle rejects polluted water, which is directly linked to the water resources that are available for use at the end of each cycle.

Water resources are defined in terms of quantity and quality. We can’t do very much to impact quantity, but water quality is very much in our control – and it impacts quantity as well. Consider this: The causes of freshwater pollution are varied. They include industrial waste, sewage, and run-off from farms, cities and factory effluents, all of which are manmade impacts. Treating a high quantity, but impaired, water resource is not practical if doing so is expensive or energy-intensive.

In many areas, combined sewer systems collect sanitary sewage and storm water runoff in a single pipe system. This can cause serious water pollution problems when large variations in flow between dry and wet weather cause the system to overflow. In the instance of an overflow, the system’s wastewater and storm water are discharged directly into a nearby river, stream, lake or ocean, thereby polluting it. For good reason, this type of sewer design is no longer used in building new communities, but many older cities still continue to use them.

In other areas, water pollution impacts more than just the ecosystem, as the map above shows. In fact, around the world, more people die from unsafe water than from all forms of violence, including war. Inadequate water, sanitation and hygiene are estimated to cause approximately 3.1 percent of all deaths each year. While we are making progress as a global community to reverse these trends, much more remains to be done.