Lake Pleasant water comes from two sources, the Colorado River via The Central Arizona Project Canal and the Agua Fria River. Generally, water is banked in Lake Pleasant during low demand periods such as the winter and released during high demand periods such as the summer. CAP utilizes Lake Pleasant to bank untreated water and CAP does not own or operate any water treatment plants, though some of CAP's customers, cities and utilities, treat and deliver Lake Pleasant water to residents. CAP is not subject to the Safe Drinking Water Act because it does not deliver water directly to residents' homes. However, as a service to municipal and industrial customers and the thousands of people who will ultimately drink the water, CAP has implemented a comprehensive water quality-testing program. Lake Pleasant is sampled quarterly for over 150 different parameters. In addition, the Agua Fria River is sampled only during flow events.