Water Equity Clearinghouse

California Office of Environmental Health Hazard Assessment


The Office of Environmental Health Hazard Assessment (OEHHA) is dedicated to the protection and enhancement of public health and the environment through scientific evaluation of risks posed by hazardous substances. OEHHA is the lead state agency within the California EPA charged with assessing health risks posed by environmental contaminants.

OEHHA has a variety of directives, such as monitoring toxic algal blooms, informing people about cancer causing chemicals in consumer products, creating interactive online tools for the public good, advocating for regulations that protect California’s most vulnerable, educating families about pesticides used in California, studying impacts of climate change on human health, and much more.

Efforts to Advance Water Equity

One of OEHHA’s main achievements has been the development of CalEnviroScreen, a tool that helps people identify which California neighborhoods are most impacted by pollution and other environmental harm. CalEnviroScreen also determines the neighborhoods’ levels of vulnerability to health and economic impacts. The tool is based on statewide information and census tract data to give users a complete picture of the environmental burdens within a community. CalEnviroScreen uses four factors in the model: exposure, environmental effects, sensitive populations, and socio-economic factors. By doing so, the tool takes into account the fact that poor neighborhoods are more likely to be located near pollution sources, and are more likely to experience high rates of asthma and unemployment. In addition, CalEnviroScreen’s developers held a number of workshops and forums to solicit feedback from residents and communities who may have valuable input.

CalEnviroScreen includes information about air, water, and soil pollution that is available to anyone with internet access to better inform residents about disparities in wealth and health. Furthermore, results from CalEnviroScreen are affecting state directives, such as Assembly Bill 1550 – Increasing Equity in California’s Climate Investments. This bill increases the percent of funding for climate projects in disadvantaged neighborhoods from 10 to 25 percent. CalEnviroScreen’s scores are being used to designate the most vulnerable census tracts in California. Many other programs, such as the Active Transport Program, the Greenhouse Reduction Funds program, and other departments under CalEPA are now using CalEnviroScreen to best determine where to allocate funds and resources. This tool helps advance equity goals throughout state agencies, nonprofits, and community based organizations.