Approximately 100% of Rainbow Municipal Water District's potable (drinking) water demand is supplied by imported water from two locations; the Lake Skinner Water Treatment Plant in Hemet and the Twin Oaks Valley Water Treatment Plant in San Marcos. 

The information and data in Table D is provided by San Diego County's water supplier Metropolitan Water District (MWD). The cornerstone of the water quality report is a table that lists the results of year-round monitoring for nearly 400 constituents. Only the constituents that are found are listed in the table. Metropolitan met all primary drinking water standards in 2020.

Rainbow Municipal Water District (RMWD) is pleased to provide you with our Annual Drinking Water Quality Report for 2022. This brochure is a snapshot of the water quality information that was compiled for 2021. Included are details about where your water comes from, what it contains, and how it compares to Federal and State standards.