#SummerScienceFriday | #KnowYourWatershed Players

The distribution and governance of water in Southern California can be convoluted. Between sources and our sinks, our water supply is overseen by many agencies across the state. We don’t often think about who overlooks our water system, so in this week’s #SummerScienceFriday, we hope to educate readers about the entities that are responsible for distributing our water.

California Department of Water Resources

All water resources in California are overseen at the state level by the California Department of Water Resources (DWR). The DWR is responsible for managing flood control systems, establishing water quality standards, ensuring sustainable water use, generating power, and educating the public on water issues (1).

Metropolitan Water District and Potable Water

The Metropolitan Water District of Southern California (MWD) is a regional wholesaler that provides water for 26 member public agencies to deliver - either directly or through their sub-agencies to people living in Los angeles, Orange, Riverside, San Bernadino, San Diego, and Ventura counties. MWD is the largest distributor of treated drinking water in the United States. MWD imports water to Southern California from the Colorado River and Northern California to supplement local supplies and also helps its member agencies develop water recycling, storage, and other local resource programs to provide additional supplies and conservation programs to reduce regional demands. MWD also collaborates with its member agencies to develop new local supplies which include programs focused on water recycling, desalination, and groundwater recovery and storage (2).

Groundwater Distributors

In order to ensure responsible and sustainable water supply, especially locally, organizations have been formed to act as watermasters. Watermasters are similar in organization and dispersal to water districts, and they are in charge of managing the quantity and quality of ground water in predetermined watersheds, as well as enforcing water rights among stakeholders. For example, these organizations set well pumping limits, monitor recharge of water back into the watershed, and monitor water quality in the watershed. Most importantly, they enforce sustainable water use and water rights, to ensure that entities aren’t taking more water than the ground can recharge (3). Due to unsustainable use of our local groundwater resources and our growing population demands, we now import most of our water from the Colorado River and Northern California. A lot of energy is needed to transport this water to our sinks, and you can learn more about the water-energy relationship in next week's blog post; the first blog post in our water-energy nexus series!

California’s water distribution system is a busy, interconnected web made up of many different entities trying to meet our state’s water demands. Check out this info graphic to follow along!