About The Illinois State Water Survey

Illinois Water Inventory Program

Frequently Asked Questions

1. Is completing the Water Inventory form mandatory?

Yes, as of January 1, 2010, annual reporting of withdrawals from wells and surface water intakes that pump at a rate of 70 gallons per minute or greater will be mandatory in the State of Illinois, according to Public Act 096-0222. The full text may be viewed here. A notable exception to the mandated reporting is the use of high-capacity well and intake use in agricultural irrigation. Agricultural irrigators are exempt from reporting for the first five years of the act (until January 1, 2015). However, individual farm irrigators with good records of irrigation water use are encouraged to report their annual water use prior to that date so their operations may serve as benchmark farms to aid in developing irrigation estimation coefficients.

2. Why is my Illinois EPA facility number wrong on the form?

For public water systems, the Water Inventory Program uses an extra digit, a "9" in the fourth place, to identify the systems as such in our database.

3. What is the SIC code?

The Standard Industrial Classification, or SIC code, is a system of classifying establishments by type of activity. The Water Inventory Program assigns SIC codes to facilities in order to make data classification and retrieval more efficient. For example, public water systems all have the code 4941, "Water Supply." Electrical power generation facilities have the code 4911, "Electric Services."

4. Should the Contact Person be the same as the person to whom the IWIP form is addressed?

Typically the form is addressed to a manager or administrator of some kind. The Contact Person is the person most knowledgeable about water use at the facility, and the person the Illinois State Water Survey can contact with any questions about the numbers reported.

6. Why are there duplicate numbers in the list of wells and surface water intake?

If the list includes both wells and surface water intakes, the intakes are listed after the wells and start with "1." An intake does not have a depth. In addition, intakes should have a particular identifying name or the word "Intake."

7. We don't have any wells. Why should we fill out this form?

The Water Inventory Program tracks the use of both self-supplied water (that is, water withdrawn from wells or surface water intakes) and purchased water. If your facility does not have wells or intakes, please leave the first part blank and go on to the next part of the form.

8. What is the difference between Total Annual Gallons Purchased and Total Annual Gallons Withdrawn?

Purchased water is the amount of water your facility buys from another facility. Withdrawn water is the amount of raw water from your own wells or surface water sources that is delivered directly to your treatment plant. Please note that the first page asks for raw water, and the second page asks about treated or finished water and how it is distributed throughout your system.

9. As an operator, I know how much water is withdrawn from our wells and intakes. How do I figure things like population, residential and commercial services, and residential and commercial quantities?

Often the billing department of your facility will have figures for population within and outside city limits, as well as the breakdown of services and quantities.

10. We have a master meter that tells us the total amount of gallons withdrawn, but we do not have exact measurements of the amount from each source. How should we report the amount from different sources?

If your wells or other sources alternate consistently, simply divide the total amount by the number of active sources. If you know the percentage output from the sources, take the percentage of the total amount and report the result in gallons.

Illinois State Water Survey

2204 Griffith Dr., MC-674
Champaign, IL 61820-7463
Email us with questions or comments.


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