Each year the DWP posts Consumer Confidence Reports, also referred to as Water Quality Reports, as directed by the California Department of Public Health. View the Consumer Confidence Report for your area below.
Each report shows the results of our monitoring for the most recent calendar year.
Our water supply is groundwater pumped from local aquifers. Perennial yield is the amount of water that can be economically extracted from a groundwater basin each year for an indefinite period of time. It cannot exceed the sum of the natural recharge, artificial recharge, and incidental recharge, without causing depletion of the basin. Perennial yield for the aquifers within the DWP service area is estimated to be 3,100 acre-feet. One acre-foot is 325,851 gallons, or enough water to cover a football field at a depth of one foot. That is approximately the amount of water a family of five uses each year.
A simpler way to think about perennial yield is to think of an aquifer as a bank account and water as money. If you withdraw more than is deposited, over time your bank account will become overdrafted. Overdrafting is exacerbated during dry years since precipitation is not replenishing the aquifers, or depositing money into the bank. That is why conservation is so important. Conservation helps us have enough water in the "bank" to get through the dry years.