Every Californian deserves access to safe and sufficient water

Coming Soon: 2022 Water Data Challenge

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Assessing What We Know + Preparing for a More Resilient Future

Data has the power to help us see challenges through different lenses, discover solutions that may not otherwise be evident, and put tools into the hands of those who need them most — empowering the community to work together in new ways. The 2020 Water Data Challenge focuses on open data to collectively assess what we know and prepare for a more resilient future. Over the span of a few months, Data Challenge teams design, develop, and extend open data projects addressing some of the state and region’s most pressing issues. 


On any given day in California, around 200,000 Californians turn on their taps and the water that comes out is unsafe to drink and may be unsafe to use for basic needs like bathing. Annually, up to 1 million Californians lack access to clean, safe drinking water at some point during the year. Droughts and other disruptions in water supply can limit or eliminate access to safe drinking water for days, months, or years. Some communities have been exposed to unsafe water for more than a decade.

Small water systems and domestic well users are particularly vulnerable to disruptions in their access to safe drinking water. While the most publicized examples are in rural areas of the state, delivering sufficient, safe, and affordable drinking water poses a challenge to small systems and domestic well users in almost every region of the state. Many of the most vulnerable systems and domestic well users rely primarily on groundwater for their water supply.

The Water Data Challenge was initially designed to explore data’s potential to help us better understand community access to safe drinking water, anticipate vulnerabilities, and identify and deploy solutions. In 2019, the scope and scale of the Challenge increased to include additional topics, encouraging collaboration with a broader range of natural resources data. This year for 2020, the Challenge features a collaboration with the State of New Mexico to further build bridges across the water data community. 

Open and Transparent Water Data

California is implementing the Open and Transparent Water Data Act to publish water and ecosystem information in an open data format. In addition to fostering the development of innovative tools and insights related to safe drinking water, the California Water Data Challenge will provide participants an opportunity to engage with the open data portal and submit feedback, advice, and suggestions for consideration as this effort is being implemented.



Web Accessibility Certification

Government Operations Agency
Certification date
June 27, 2019
Andrew Armani

The undersigned certify that, as of June 27, 2019, the waterchallenge.data.ca.gov internet website is designed, developed and maintained to be in compliance with California Government Code Sections 7405 and 11135, and the Web Content Accessibility Guidelines 2.0, or a subsequent version, June 27, 2019, published by the Web Accessibility Initiative of the World Wide Web Consortium at a minimum Level AA success criteria.


Marybel Batjer
June 27, 2019
Andrew Armani
June 27, 2019
Agency Information Officer