Water sustainability solutions should be taken seriously by everyone. Sustainable water systems provide appropriate water quality and adequate water quantity for a given need without affecting the future ability to provide the same quality and capacity. Water systems in the context of sustainable development may not include the use of water, but it includes systems where water use has traditionally been required. Some of the examples include waterless car washes and waterless toilets whose use helps secure a sustainable supply of water and alleviate water stress. Here are some of the water sources found on earth.
Surface water
Surface clean water is unequally distributed and limited in the world. Nearly 50% of freshwater lakes in the world are located in Canada. Pollution from various activities contaminate surface water and render it unsafe for drinking. Treatment systems should, therefore, be put in place to treat surface water before it is used.
Structures such as dams can be used to impound freshwater for use. Dams can also be used to generate power, irrigation, water supply, water diversion, food prevention, navigation and more. If properly constructed, dams can provide a sustainable water supply. When designing dams, it is necessary to consider peak flood flows, soil permeability, earthquake faults, erosion, slope stability, water table, silting, wetlands, human impacts, and compensation for resettlement, ecological impacts and other site features. There are numerous challenges that large scale dam projects pose to sustainability such as fish migration, wildlife habits, water flow and quality and more. Nevertheless, dams are still good water sustainability projects.
Groundwater
Groundwater is critical for potable water because it accounts for more than 50% of the world’s freshwater. Groundwater can be another major source of sustainable water if the total amount of water that enters, leaves and gets stored in the system is conserved. Three main factors determine the source and amount of groundwater: location of streams and other surface-water bodies, precipitation and evapotranspiration rate. This makes it impossible to generalize a sustainable pumping rate or withdrawal for groundwater. Unsustainable use of groundwater leads to water-level decline, low water quality, reduced streamflow and jeopardizing the livelihood of the communities affected.
Rainwater harvesting
Collecting rainwater is one of the most sustainable water sources since it has no risk of over-exploitation found in ground and surface water sources. Harvesting rainwater directly provides water for drinking. However, it is important to design the harvesting and maintain it properly to collect water efficiently, avoid contamination and use sustainable treatment systems in case of contamination. Different water treatments for harvested rainwater exist including boiling, solar treatment, chlorination, flocculation and more.
Desalinization
Desalinization can ensure water sustainability solutions as it has the potential to provide enough water quantity to those places that don’t have enough freshwater including small island states. The downside to this method is that the energy needs of reverse osmosis are high and this makes desalinization to be ineffective in most places. However, the energy needed for this process can be provided with renewable energies, it can increase the sustainable feature of desalination.