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 2018.
By reading the table from left to right, you will learn the quantity of a constituent found in Metropolitan’s water and how that compares with the allowable state and federal limits. You will also see the measured range and average of the constituent and where it likely originated.