To our Valued Customers:

We are committed to providing you, our customers, with water that meets and often surpasses all water quality regulations. Our state-of-the-art laboratory tests our water at the wellhead, at various stages of treatment and within the distribution system for bacteria and a wide range of inorganic and organic chemicals. In fact, we test our drinking water for far more chemicals than required and at a frequency far in excess of local, state and federal regulations. Because of these stringent safeguards, we can assure our customers that the water we deliver to them is of high quality.

Please click on the link below to view the Suffolk County Water Authority's 2020 Annual Drinking Water Quality Report, which covers all of our testing for the calendar year 2019. The report also includes charts, data, maps and information about the quality of your drinking water. I hope the report answers all of your questions, but if not, please do not hesitate to call our Customer Service Center at (631) 698-9500.

To access the annual water quality report for any other recent year, choose the applicable link below.

Kevin Durk,

Director of Water Quality and Laboratory Services


2021 Annual Water Quality Report

2020 Annual Water Quality Report

2019 Annual Water Quality Report

2018 Annual Water Quality Report

2017 Annual Water Quality Report



Supplemental Reports

SCWA’s Supplemental Reports contain raw water quality information from each of our well fields. The range of data presented shows the lowest value for a detected analyte, the highest value, the average value, and the total number of tests conducted at each well field. These values represent an average of all the individual wells at each well field.

To access the supplemental report for the year of your choice, please click on the applicable link below. For a list of analytes tested for but not detected, please click the Negative Analytes button after opening the link.


2021 Supplemental Report

2020 Supplemental Report

2019 Supplemental Report

2018 Supplemental Report

2017 Supplemental Report



Islip Harvest Lane and Old Nichols Road Results