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PURPOSE OF THIS REPORT
This report is
produced to provide information about the City of Laredo sources of water, the
content of Laredo water, and answer water quality question. If you have more
questions about water quality, please call (956) 795-2600.

SPECIAL INFORMATION FOR PEOPLE WITH
WEAKENED IMMUNE SYSTEMS
Some people may be more vulnerable to
contaminants in drinking water than the general population. Immuno-compromised
persons such as persons with cancer undergoing chemotherapy, persons who have
undergone organ transplants, people with HIV/AIDS or other immune system
disorders, some elderly, and infants can be particularly at risk from
infections. These people should seek
advice about drinking water from their health care providers. Environmental Protection Agency/Center for
Disease Control guidelines on
appropriate means to lessen the risk of infection by Cryptosporidium and other
microbial contaminants are available from the Safe Drinking Water Hotline
(1-800-426-4791).
When drinking water meets
federal standards there may not be any health-based benefits to purchasing
bottled water or point of use devices. Drinking water, including bottled water,
may reasonably be expected to contain at least small amounts of some
contaminants. The presence of contaminants does not necessarily indicate that
water poses a health risk. For more
information about contaminants and potential health effects please call the
EPA’s Safe Drinking Water Hotline (1-800-426-4791).
WATER SOURCE

The only source of Laredo’s
water is the Rio Grande River. The City
of Laredo Utilities Department pumps from the Rio Grande River an average of 40
million gallons of water per day, and complies with specific and strict
treatment guidelines to produce drinking water with the highest water quality
ranking issued by the State of Texas—“SUPERIOR.” The constituents and values
found in this report are monitoring requirements established by State and
Federal guidelines to track the quality of your drinking water.
City of Laredo water is purified through chemical treatment,
settling, filtration, and disinfection. Water treatment che-
micals including lime, ferric sulfate,
chloramines (chlorine and ammonia), powdered activated carbon, and polymers
are added to water to remove
impurities, kill harmful bacteria, eliminate tastes and odors help prevent
tooth decay.

As the charts show, the levels of contaminants
in Laredo water meet all the standards require by law. Laredo regularly test drinking water for
more than 540 contaminants. About 580 tests each month are conducted to ensure
the quality of the water.
Regulations Applicable at Treatment Plant
|
Year |
Constituent |
Range of Detected
Levels |
Highest
LevelDetected |
MCL |
MCLG |
Unit of Measure |
Possible
Source of Contamination |
|
2001 |
Barium |
0.010-0.085 |
0.085 |
2 |
2 |
ppm |
Erosion of natural deposits; Discharge of drilling wastes;
Discharge from metal refineries. |
|
2001 |
Fluoride |
0.3-0.6 |
0.6 |
4 |
4 |
ppm |
Erosion of natural deposits; Discharge from fertilizer and
aluminum factories. |
|
2001 |
Nitrate |
0.01-0.46 |
0.46 |
10 |
10 |
ppm |
Erosion of natural deposits; Runoff from fertilizer use;
Leaching from septic tanks, sewage. |
|
Year |
Constituent |
Range of
detected levels |
Average of all sampling
points |
Unit of Measure |
Reason for monitoring
|
|
2001 |
Chloroform |
6.4-32.0 |
13.9 |
ppb |
Unregulated contaminant monitoring helps EPA to determine
where certain contaminants occur and whether it needs to regulate those
contaminants. |
|
2001 |
Bromoform |
3.0-12.0 |
8.7 |
ppb |
Unregulated contaminant monitoring helps EPA to determine
where certain contaminants occur and whether it needs to regulate those
contaminants. |
|
2001 |
Bromodichloromethane |
14.6-18.4 |
16.9 |
ppb |
Unregulated contaminant monitoring helps EPA to determine
where certain contaminants occur and whether it needs to regulate those
contaminants. |
|
2001 |
Dibromochloromethane |
11.6-25.4 |
19.9 |
ppb |
Unregulated contaminant monitoring helps EPA to determine
where certain contaminants occur and whether it needs to regulate those
contaminants. |
|
Year |
Constituent |
Lowest
Monthly % of Samples Meeting Limit * |
Lowest
Monthly Limit * |
Highest Single
Reading |
Unit of Measure |
Source of Constituent
|
|
2001 |
Turbidity |
100% |
92% |
.21 ** |
NTU |
Soil runoff. |
* Turbidity must be less than .5 NTUs in at least 95% of monthly
samples.
* The highest single monthly reading in 2001 was .21 (September).
Regulations Applicable in Distribution System
Year
|
Constituent |
Range of
Detected Levels |
Highest
LevelDetected |
MCL |
MCLG |
Unit of Measure |
Possible
Source of Contamination |
|
1999 |
Gross Alpha Adjusted |
1.6 |
1.6 |
15 |
0 |
pCi/l |
Erosion of natural deposits. |
|
2001 |
Total Trihalomethanes |
54.8-65.0 |
62.1 |
80 |
80 |
ppb |
By-product of drinking water chlorination. |
|
Year |
Constituent |
Highest
Monthly % of Positive Samples |
MCL |
Unit of Measure |
Source of Constituent |
|
2001 |
Total Coliform Bacteria |
1.7% |
5% |
Presence |
Naturally present in the environment. |
Regulations Applicable
at Customer’s Tap
|
Year |
Constituent |
90th
Percentile |
# of sites
exceeding action level |
Action level |
Unit of measure |
Source of Constituent
|
|
1999 |
Lead |
2.80 |
0 |
15 |
ppb |
Corrosion of household plumbing systems; erosion of natural
deposits. |
|
1999 |
Copper |
0.06 |
0 |
1.3 |
ppm |
Corrosion of household plumbing systems; erosion of natural
deposits; leaching from wood preservatives. |
The information contained in this
report is based on official data compiled by the Texas Natural Resource
Conservation Commission (TNRCC) in 2001.
Maximum Contaminant Level
(MCL) - The
highest level of a contaminant that is allowed in drinking water. MCL’s are set as close to the MCLG’s as
feasible using the best available treatment technology.
Maximum Contaminant Level Goal
(MCLG) - The
level of a contaminant in drinking water below which there is no known or
expected health risk. MCLG’s allow for
a margin of safety.
Action Level - The concentration of a
contaminant which, if exceeded, triggers treatment or other requirements a
water system must follow.
Nephelometric Turbidity Units
(NTU) - The
unit used to measure water turbidity.
Turbidity - A measurement of the cloudiness
of water. The lower the turbidity the better.
Treatment Technique - A required process, i.e.
filtration, intended to reduce the level of a contaminant (such as turbidity)
in drinking water.
ppm - Parts per million.
ppb - Parts per billion.
pCi/l - Pico-curies per liter (a measure of radioactivity).
HEALTHY HYDRATION

By now, we've
all heard that we should drink 8 to 10 glasses of water a day, just to maintain
a healthy level of hydration.
Drinking water also contributes to health and living well in three other ways:
This report is mailed to all Laredo Water
Utilities customers.
It is available in the
Water
Utilities Department and on the

City of Laredo
Water Utilities
5816 Daugherty
Laredo, TX 78041