In moving toward a safe and sustainable water future for Los Angeles County we must learn to conserve water, replenish groundwater, and safely reuse water so that there is net zero water waste. There are many ways to approach this goal. Thanks to recent changes in State law, many opportunities now exist to reuse water safely. It is clear that if Los Angeles is to be successful in building a sustainable water future, we must learn to reduce the use of potable water (i.e. drinking water) for purposes such as flushing toilets, landscape irrigation, and washing clothes. One method to reduce the use of potable water for these tasks is to promote the safe use of alternate, non-potable water sources, such as rainwater, graywater, and stormwater. These alternate water sources can be used safely for a variety of indoor and outdoor uses, as long as public heath requirements are met. To assist the public with information on how to collect and safely use alternate water sources, the Los Angeles County Department of Public Health (DPH), Environmental Health Division (EH) prepared this document, in collaboration with stakeholders, as a guide for the safe use of alternate water sources in indoor and outdoor settings. These guidelines are intended to provide a user-friendly roadmap for alternate water use; however, it is ultimately the responsibility of the system owner and operator to ensure that nonpotable water sources are used appropriately and monitored for safety throughout the life of the project.