Center for Law, Energy & the Environment Publications

Document Type


Publication Date



California’s water management systems are struggling to meet environmental and human needs in the face of stresses from climate, population, and land use changes. Calls to improve the operation, management, and infrastructure of water systems are frequent. Making rational and equitable water management decisions depends upon timely knowledge of the current and projected state of the water system. This, in turn, requires robust data and information. Currently, California’s water data fall far short of the fundamental goal of being complete, accessible, and usable—that is, readily available in formats that suit users’ needs, at relevant spatial and temporal resolutions that are useful for making the decisions at hand. Data sources are incomplete and inconsistent. Fragmented data systems often cannot exchange data with one another. Existing data are frequently difficult to access or use. Ironically, the birthplace of modern information technology lacks both basic information and the capacity to use it effectively to manage its most precious resource. Strategic, coordinated investments in California’s water information infrastructure are necessary. Without basic information on where, when, and how much water is available and being used, as well as physical, chemical, and biological measurements of water quality, we cannot improve how we manage our water resources. A modern water data system that enables accurate, timely, transparent accounting of water supply, quality and use could enhance water security and sustainability. With better and more usable data informing water management, California’s existing water resources could better meet urban, agricultural, ecological and industrial needs. California’s 2016 Open and Transparent Water Data Act (AB 1755) provides an important opportunity for improving the state of water data in California. The bill charges state agencies with integrating currently fragmented water and environmental data systems. However, while AB 1755 provides an opening for improved data systems, the law itself does not ensure increased usability of data for decision making. Increased usability of data requires a broader rethinking of data systems and their interactions as applied to decision making contexts.