#SummerScienceFriday | Energy-Water Nexus Series: Our Water Supply


 We often think of energy and water as separate resources, each being indispensable to human life. However, they heavily depend on one another and can pose a threat to our supply of these resources when we don't make an effort to conserve them . For this week’s #SummerScienceFriday, we begin our Energy-Water Nexus Series, where we explore the link between water and energy and learn ways that we can conserve them.


Where does our water come from?

Even though water is easily accessible through our sinks and faucets, it actually travels a long way before it reaches our homes. Los Angeles’ water supply comes from three sources: the State Water Project, the Los Angeles Aqueduct, and the Colorado River Aqueduct. When available, groundwater wells pump water from groundwater basins to the surface. Through the State Water Project (a system of reservoirs, pump stations, power plants, pipes, and canals), water is mainly collected as snowmelt in Northern California (Owens River and Mono Lake Basin) and the Sierra Nevada Mountains. As the snowpack melts, the water turns into streams and rivers that run into lakes and aqueducts and then transported to LA through the Los Angeles Aqueduct (1). The groundwater basins also rely on seasonal processes to replenish the water basins. When it rains, the ground becomes saturated with water, which subsequently flows through the soil, forming large pockets of water underground. Today, many of LA’s water basins are refilled by stormwater capture projects and some spreading grounds replenish the basins. 


The transport and usage of water heavily relies on energy. According to UC Davis, 20% of all energy in California and 30% of natural gas consumption goes to water (2). The large quantity of energy and gas are used to transport, pump, heat , cool, and purify water. Therefore, it is crucial that we work towards conserving these resources.


Stresses in Southern California