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SDWIS Search User Guide

SDWIS Banner

SDWIS icon This is a brief user's guide to the SDWIS Search. Select between a variety of different search options and output options detailed below. 

Geography Search Option

To select an area in which to search, click on that state or territory within the map provided or on the text link for that state or territory below the map. Links for EPA-regulated territories outside the scope of the map are provided as well. Once a geographic area is selected, users can search based on: water system name, county name, and/or population served.

Open the SDWIS Search in a new tab or window.

How do I find a Water System:

Step 1: Find Your Water System

(Note: This process will be most successful if you know the name of your water system. To find this information, either check your most recent water bill or look in the local government section of your phone book)

  • Select the state where you live.
  • At the line that says "Water System Name" select "Containing" and then type in what you think the name of your water system is (It doesn't need to be the whole name. Type in only as much as you are sure of, e.g., "Jonesville Water District.") and press the search button.
  • Scan the list of water systems that Envirofacts finds. Do any of these appear to be your system? Look carefully at the Water System Name, County Served, and Population Served to determine if this is your water system. The water systems serving the same people year-round, called "Community Water Systems," will appear first. Your water system is most likely a community water system.
  • If none of these sounds correct, go back to the search screen and try searching for just the name of your city, e.g., "Jonesville."
  • If this search also fails, try either a county search (which will show you all the water systems which principally serve a specific county) or a search by system size (where you can locate, for example, all the water systems in your state that serve over 100,000 people). If neither of these two searches work, try a water system name search again using less specific words, e.g., "Jones." You can combine these three searches and search in all categories (name, county, population), but the more specific you are, the more likely you are to not find any systems that match your search criteria. You may need to consult your water bill or phone book to find your water system's name and try again.

Step 2: View your water system

  • Once you have located your water system, select it by clicking on the name of the system. This will take you to a screen which will list any violations your system has had of EPA safety standards for drinking water.
  • If there aren't any violations listed, your water system meets all federal drinking water safety standards, and your water should be considered safe to drink.

Step 3: What if there are violations?

If there are violations, there are several key things you should look at:

  • When did the violation occur? (Look at beginning and ending dates of the violation period to give you the time frame the violation occurred in.) Was the violation recent or did violations several years ago and not since then? Is there a pattern of violations?
  • What type of violation occurred? Violations will be displayed in two tables. The first table lists "health-based violations." These violations occur when a water systems detects levels of a contaminant exceeding the safety level (called the maximum contaminant level (MCL)) or when the water system fails to treat the water as required to remove particular contaminants (called a treatment technique violation). Other violations include monitoring and reporting violation (which indicate that the water system failed to complete are required sampling or to do so in a timely manner). Specific definitions for what each violation means are available by clicking on the column Type of Violation.
  • What contaminant was the violation for? Click on the contaminant name to see why each is regulated by EPA and what its health effects are at levels above EPA's safety standards.

Notes: For many contaminants, an exceedence of the EPA safety level (MCL) may not by itself be a cause for immediate concern. Many contaminants are only a concern if ingested at levels well in excess of the safety standards over many years.

Monitoring violations do not necessarily indicate that the drinking water is not safe. Monitoring violations can occur for many reasons; the best way to find out why your system has monitoring violations is to call your water system directly.

Step 4: If there were violations, what has been done about it?

This question is answered in the follow-up action section following each violation. Look to see if any actions have been taken. Actions can be taken by either the federal government (EPA) or by states. If no action has been taken for a violation, as recorded in SDWIS,one of four things has occurred:

  • an informal action (not federally defined) was taken to correct the problem,
  • a formal action (federally defined) was taken to correct the problem but not reported to EPA,
  • no action was taken to correct the problem, or
  • an action to correct the problem is pending.

If action has been taken and reported, look at:

  • What action was taken? (By clicking on the column heading, Follow-up Action, you can see what each individual action means).
  • When was the action taken? (Date of Response)

Step 5: How can I find out more?

If you are concerned about the violations your system has, there are several things you can do to find out more information.