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EF/ ICR Logo Levels of Treated Water Total Trihalomethanes for CALIFORNIA
APRIL - JUNE 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.




Alameda County Water District

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Blending Facility 135 Ground Water APR 1998 - JUN 1998 46.4

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Mission San Jose WTP 137 Surface Water APR 1998 - JUN 1998 47.9
WTP2 136 Surface Water APR 1998 - JUN 1998 24.3



CITY OF LOS ANGELES

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Los Angeles Aqueduct Filtration Plant 163 Surface Water APR 1998 - JUN 1998 41.2
Lower Stone Canyon Reservoir 166 Surface Water APR 1998 - JUN 1998 61.5
River Supply Conduit 738 Surface Water APR 1998 - JUN 1998 57.1
Upper Hollywood Reservoir 739 Surface Water APR 1998 - JUN 1998 54.8



CITY OF SANTA BARBARA

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
W.B. CATER WTP 231 Surface Water APR 1998 - JUN 1998 58.3



CITY OF VALLEJO

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Fleming Hill Water Treatment Plant 239 Surface Water APR 1998 - JUN 1998 47.3



California Domestic Water Company

NO DATA - Click here to find out why.



California Water Service Co, Bakersfield

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Groundwater Trmt - Well #7-07 150 Ground Water APR 1998 - JUN 1998 .4



California-American Water Company

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Carmel Valley Filter Plant 183 Surface Water APR 1998 - JUN 1998 52.7



Castaic Lake Water Agency

NO DATA - Click here to find out why.



City of Anaheim

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Linda Vista Reservoir 186 Ground Water APR 1998 - JUN 1998 25.9



City of Escondido

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Escondido - Vista WTP 215 Surface Water APR 1998 - JUN 1998 66



City of Fresno, Water Division

NO DATA - Click here to find out why.



City of Fullerton

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Main Water Plant 187 Ground Water APR 1998 - JUN 1998 1.4



City of Huntington Beach - Public Works

NO DATA - Click here to find out why.



City of Modesto

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
City of Modesto, Groundwater Treatment 243 Ground Water APR 1998 - JUN 1998 3.7



City of Oceanside

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Mission Basin Desalting Facility 753 Ground Water APR 1998 - JUN 1998 40.7

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Robert A. Weese Filtration Plant 217 Surface Water APR 1998 - JUN 1998 47.5



City of Riverside

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Grand Terrace 201 Ground Water APR 1998 - JUN 1998 3.1



City of Sacramento

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Groundwater Treatment Plant 742 Ground Water APR 1998 - JUN 1998 3.9

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
E.A. Fairbairn Water Treatment Plant 205 Surface Water APR 1998 - JUN 1998 42.1
Sacramento River Water Treatment Plant 204 Surface Water APR 1998 - JUN 1998 46.3



City of San Diego Water Utilities

NO DATA - Click here to find out why.



City of Santa Ana

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Groundwater Treatment 189 Ground Water APR 1998 - JUN 1998 2.3



Coachella VWD: Cove

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Groundwater Treatment 196 Ground Water APR 1998 - JUN 1998 .6



Contra Costa Water District

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Bollman Water Treatment Plant 146 Surface Water APR 1998 - JUN 1998 41.5



Cucamonga County Water District

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Reservoir 1 (Chino Basin) 743 Ground Water APR 1998 - JUN 1998 8.4

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Lloyd W. Michael WTP 208 Surface Water APR 1998 - JUN 1998 32.1
Royer/Nesbit WTP 209 Surface Water APR 1998 - JUN 1998 7.2



Dominguez Water Corp.

NO DATA - Click here to find out why.



EAST BAY MUNICIPAL UTILITY DISTRICT

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Layfayette Filter Plant 143 Surface Water APR 1998 - JUN 1998 53.3
Orinda Filter Plant 138 Surface Water APR 1998 - JUN 1998 49.7
Sobrante Filter Plant 141 Surface Water APR 1998 - JUN 1998 70.1
Upper San Leandro Filter Plant 139 Surface Water APR 1998 - JUN 1998 111.8
Walnut Creek Filter Plant 140 Surface Water APR 1998 - JUN 1998 54.6



Helix Water District

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
R. M. Levy 216 Surface Water APR 1998 - JUN 1998 61.2



LONG BEACH WATER DEPARTMENT

NO DATA - Click here to find out why.



Marin Municipal Water District

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Bon Tempe Treatment Plant 181 Surface Water APR 1998 - JUN 1998 35.4



Metro Water Dist of So Calif

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
F. E. Weymouth FP 171 Surface Water APR 1998 - JUN 1998 66.1
J. Je nsen FP 168 Surface Water APR 1998 - JUN 1998 70.7
R. A. Skinner FP 170 Surface Water APR 1998 - JUN 1998 78.7
R. B. Diemer FP 169 Surface Water APR 1998 - JUN 1998 61.5



North Bay Regional Water Treatment Plant

NO DATA - Click here to find out why.



Ontario-City of

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Well No. 34 211 Ground Water APR 1998 - JUN 1998 0



SONOMA COUNTY WATER AGENCY

NO DATA - Click here to find out why.



San Bernardino Municipal Water Dept.

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Newmark Pumping Plant 212 Ground Water APR 1998 - JUN 1998 1.5



San Francisco Water Department

NO DATA - Click here to find out why.



San Gabriel Valley WC - Fontana

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Sandhill Treatment Plant 214 Surface Water APR 1998 - JUN 1998 4.9



San Gabriel Valley Water Company

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Various Wells Main San Gabriel Basin 153 Ground Water APR 1998 - JUN 1998 0



San Jose Water Company

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Well Fields 234 Ground Water APR 1998 - JUN 1998 1.5

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Montevina WTP 232 Surface Water APR 1998 - JUN 1998 38.5
Saratoga WTP 233 Surface Water APR 1998 - JUN 1998 20.5



San Juan Water District

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Sidney N. Peterson WTP 206 Surface Water APR 1998 - JUN 1998 29 .5



Santa Clara Valley Water District

NO DATA - Click here to find out why.



Stockton East Water District

NO DATA - Click here to find out why.



Sweetwater Authority

Water Type - SURFACE WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Robert A. Perdue Water Treatment Plant 221 Surface Water APR 1998 - JUN 1998 101



The City of Garden Grove

Water Type - GROUND WATER
(Treated Water)

Plant Name Plant ID Water Type Quarter Total Trihalomethanes Concentration (ppb)
Lampson Reservoir 194 Ground Water APR 1998 - JUN 1998 2.3



Three Valleys Municipal Water District

NO DATA - Click here to find out why.



Water Facilities Authority

NO DATA - Click here to find out why.



Zone 7 Water Agency

NO DATA - Click here to find out why.



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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