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EF/ ICR Logo Levels of Treated Water Total Trihalomethanes for ILLINOIS
JULY - SEPTEMBER 1998


REMINDER: Data Purpose: The ICR data were collected as part of a national research project to support development of national drinking water standards. They should NOT be used to determine local water systems compliance with drinking water standards, nor should they be used to make personal judgements about individual health risks.

Units: Sample measurements are taken in micrograms per Liter (ug/L) and are regulated in milligrams per Liter (mg/L). A microgram per Liter is equivalent to one contaminant part per billion (ppb). A ppb can be thought of as one grain of salt in a swimming pool. Data for Total Trihalomethanes, haloacetic acids 5, and bromate are presented in ppb. 1 mg/L = 1000 ug/L, or 0.080 mg/L = 80 ug/L = 80 ppb, which happens to be the TTHM standard in the Stage 1 DBP Rule.

Calculation in Regulations is Different: Comparisons with compliance calculations based on the existing Total Trihalomethanes standard in CFR Part 141.30 may not be warranted since the standard i s based on an annual average of public water system quarterly averages and not on treatment plant results as shown here. Also the results here are based on different types of samples.

Results of Zero: A result of zero may indicate that a sample was analyzed, but that the result was less than the lowest value that the analytical method can reliably report.




Central Lake County Water Agency

NO DATA - Click here to find out why.



Chicago Water Department

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Jardine Water Purification Plant 354 Surface Water JUL 1998 - SEP 1998 24
South Water Purification Plant 355 Surface Water JUL 1998 - SEP 1998 28.7



City of Aurora

NO DATA - Click here to find out why.



City of Evanston Water Utility

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Evanston Water Utility 347 Surface Water JUL 1998 - SEP 1998 27.8



City of Rockford P.W. Water Division

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Deep Aquifer (30 wells) 366 Ground Water JUL 1998 - SEP 1998 7.1



IL-American Water Co. - East St. Louis

NO DATA - Click here to find out why.



IL-American Water Co. - Peoria

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Dodge St. Well Station 362 Ground Water JUL 1998 - SEP 1998 13.1
San Koty Treatment Plant 361 Ground Water JUL 1998 - SEP 1998 25.2

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Illinois River Water Treatment Plant 360 Surface Water JUL 1998 - SEP 1998 107.6



Northern Illinois Water Corp.- Champaign

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
East Plant 346 Ground Water JUL 1998 - SEP 1998 1.1
West Plant 345 Ground Water JUL 1998 - SEP 1998 1.8



Rend Lake Intercity Water System

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Rend Lake Intercity Water System 358 Surface Water JUL 1998 - SEP 1998 64.8



Springfield Water, Light & Power

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Water Purification Plant 365 Surface Water JUL 1998 - SEP 1998 60.2



Results for mixed water (ground water and surface water) and purchased water can be found under water system summary reports.


How does this state's treated water compare to treated waters nationally for Total Trihalomethanes?
View national data for the same month.


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