2016 South Tahoe Public Utility District
CONSUMER CONFIDENCE REPORT 2016
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IS MY WATER SAFE? Last year, as in years past, You may view the document by visiting the herbicides, may come from a variety of sources RESULTS OF RADON MONITORING Radon is a
your tap water met all U.S. Environmental District's website at www.stpud.us or by such as agriculture, urban stormwater runoff, radioactive gas that you can't see, taste or
Protection Agency(EPA) and state drinking requesting a copy by calling Customer Service and residential uses. Organic chemical smell. It is found throughout the U.S. Radon can
water health standards.The South Tahoe Public at 530-544-6474. contaminants, including synthetic and volatile move up through the ground and into a home
Utility District vigilantly safeguards its water The District has an ongoing drinking water organic chemicals, are by-products of industrial through cracks and holes in the foundation.
supplies and, once again,we are proud to source development program that seeks potential processes and petroleum production, and can Radon can build up to high levels in all types of
report that our system has not violated a drinking water well locations. Due to the volume also come from gas stations, urban stormwater
maximum contaminant level or any other water of the average annual Sierra snowpack and runoff, agricultural application and septic homes. Radon can also get into indoor air when
quality standard. Lake Tahoe itself, our aquifer has a significant systems. Radioactive contaminants, can be released from tap water from showering,
DO I NEED TO TAKE SPECIAL PRECAUTIONS? recharge capability. The District continues to naturally occurring or be the result of oil and washing dishes, and other household activities.
work diligently to protect and maintain this gasproduction and miningactivities. In order to Compared to radon enteringthe home through
Some people may be more vulnerable to p g
precious natural resource. ensure that tap water is safe to drink, the United soil, radon entering the home through tap water
contaminants in drinking water than the
general population. Immunocompromised WHY ARE THERE CONTAMINANTS IN MY States Environmental Protection Agency(USEPA) will, in most cases, be a small source of radon
persons such as persons with cancer undergoing DRINKING WATER?Drinking water, including and the California Department of Public Health in indoor air. Radon is a known human
chemotherapy, persons who have undergone (DPH) prescribe regulations that limit the amount
9 bottled water, may reasonably be expected to carcinogen. Breathing air containing radon can
organ transplants, people with HIV/AIDS or contain at least small amounts of some of certain contaminants in water provided by lead to lung cancer. Drinking water containing
other immune system disorders, some elderly, contaminants.The presence of contaminants public water systems. Food and Drug radon may also cause increased risk of stomach
and infants can be particularly at risk from does not necessarilyindicate that waterposes a Administration (FDA) regulations establish limits
cancer. If you are concerned about radon in
infections.These people should seek advice t i t
health risk. More information about for contaminants in bottled water which must
contaminants and potential health effects can be provide the same protection for public health. your home, test the air in your home. Testing is
about drinking water from their health care
providers. EPA/Centers for Disease Control inexpensive and easy. Fix your home if the level
obtained by calling the Environmental Protection HOW CAN I GET INVOLVED?The information
(CDC) guidelines on appropriate means to Agency's (EPA) Safe DrinkingWater Hotline of radon in your air is 4 picocuries per liter of
lessen the risk of infection byCr tos oridium contained in the Consumer Confidence Report
yp p (1-800-426-4791). The sources of drinkingair(pCi/L) or higher. There are simple ways to
and other microbial contaminants are available ( ) may not answer all the questions you may have
water(both tapwater and bottled water) includefix a radon problem that aren't too costly. For
from the USEPA's Safe Water Drinking Hotline about the quality of the South Tahoe Public additional information, call your state radon
(1-800-426-4791). rivers, lakes, streams, ponds, reservoirs, springs, Utility District's drinking water supply. The
and wells.As water travels over the surface of District welcomes public participation in program or call EPA's Radon Hotline
WHERE DOES MY WATER COME FROM?There the land or through the ground, it dissolves developing water quality and quantity policy. If (800-SOS-RADON).
are 11 active drinking water and 4 standby naturally occurring minerals and, in some cases, you would like more detailed scientific
wells to more than 14,000 homes and RESULTS OF VOLUNTARY MONITORING
radioactive material, and can pick up information, please call the District Laboratory at
businesses. All our drinking water is pumped substances resulting from the presence of 530-544-6474 extension 6231, or check our See data sheets.
from underground aquifers. No water is animals or from human activity. Microbial website at www.stpud.us. REGARDING ARSENIC Arsenic is a naturally
taken from Lake Tahoe or any other surface contaminants, such as viruses and bacteria, may The District is governed by an elected five-
water source. occurring substance that is sometimes found at
come from sewage treatment plants, septic member Board of Directors. Board meetings are
very low levels in drinking water, primarily
SOURCE WATER ASSESSMENT AND systems, agricultural livestock operations, and held on the first and third Thursday of each
PROTECTION The District's Groundwater wildlife. Inorganic contaminants, such as salts month at 2 p.m. at the Customer Service Facility groundwater. The U.S. Environmental Protection
Management Plan (California Water Code and metals, can be naturally occurring or result located at 1275 Meadow Crest Drive. All Agency(EPA)was required by the Safe Drinking
Section 10750) was adopted on December 4, from urban stormwater runoff, industrial, or meetings are open to the public and the District Water Act Amendments of 1996 to finalize a
2014 and is on file with the California domestic wastewater discharges, oil and gas encourages our customers to attend and become new drinking water standard for arsenic in 2001
Department of Public Health (CDPH). production, mining, or farming. Pesticides and involved in the policy making process. based on good scientific information and data.
SPANISH(ESPANOL)Este informe contiene informacion muy importante sobre la calidad de su agua beber.Traduscalo o hable con alguien que to entienda bien.
WATER QUALITY DATA TABLE The table below lists presented in this table is from testing done in the ADDITIONAL CONTAMINANTS In an effort to insure IMPORTANT DRINKING WATER
all of the drinking water contaminants that we calendar year of the report.The EPA or the State the safest water possible, the State has required us to DEFINITIONS
detected that are applicable for the calendar year of requires us to monitor for certain contaminants less monitor some contaminants not required by Federal MCLG Maximum Contaminant
this report.The presence of contaminants in the water than once per year because the concentrations of regulations. Of those contaminants only the ones Level Goal: The level of a
does not necessarily indicate that the water poses a these contaminants do not change frequently. listed on the last page under"Additional contaminant in drinking water
health risk. Unless otherwise noted, the data Contaminants"were found in your water. below which there is no known
or expected risk to health.
MCLGs allow for a margin of
CONTAMINANTS MCLG/PHG MCL OR MRDL AVERAGE MIN MAX SAMPLE VIOLATION TYPICAL SOURCE safety.
OR MRDLG OR NL DATE MCL Maximum Contaminant
INORGANIC CONTAMINANTS Level:The highest level of a
contaminant that is allowed in
Arsenic(ppb) 0.004 10 2.8 ND 7.0 2016 No Erosion of natural deposits;Runoff drinking water. MCLs are set as
from orchards;Runoff from glass and close to the MCLGs as feasible
electronics production wastes using the best available
Fluoride(ppm) 1 2 0.08 ND 0.19 2016 No Erosion of natural deposits;Water treatment technology.
additive which promotes strong teeth; PDWS Primary Drinking Water
Discharge from fertilizer and aluminum Standards: MCLs for
factories contaminants that affect health
Nitrate[measured as Nitrogen](ppm) 10 10 0.21 0.03 0.53 2016 No Runoff from fertilizer use;Leaching from along with their monitoring and
septic tanks,sewage;Erosion of natural reporting requirements, and
deposits water treatment requirements.
A
Act
Le
Sodium(ppm) NA NA 11.6 4.54 30.7 2016 No Erosion of natural deposits;Leaching concentration on ofel:The
of a contaminant
RADIONUCLIIDES which, if exceeded, triggers
treatment or other requirements
Gross Alpha(pCi/L),minus Uranium 15 3.68 0.30 11.08 2016 No Erosion of natural deposits which a water system must
follow.
Uranium(pCi/L) 0.43 20 5.65 1.41 13.7 2016 No Erosion of natural deposits PHG Primary Health Goal:The
Radium-226(pCi/L) 0.05 0.69 0.58 0.88 2016 No Erosion of natural deposits level of contaminant in drinking
wRadium-228(pCi/L) 0.019 1.52 0.48 2.36 2016 No Erosion of natural deposits is noor knownbelow below expectedwdh there
to
is or risk to
Radium-226+Radium-228 5 2.21 1.10 2.94 2016 No Erosion of natural deposits health. PHGs are set by the
California Environmental
VOLATILE ORGANIC CONTAMINANTS Protection Agency.
MTBE[Methyl Tert Butyl Ether] (ppb) 5 13 ND ND ND 2016 No Leaking underground fuel storage tanks MRDLG Maximum Residual
Disinfection Level Goal:The
Total Trihalomethanes(ppb) NA 80 2.0 ND 8.5 2016 No By-product of drinking water disinfection level of a drinking water
de
HaloAcetic Acids(ppb) NA 60 0.2 ND 1.5 2016 No By-product of drinking water disinfection is nofectant below expectedwcd riskthe to
known or risk to
MICROBIOLOGICAL CONTAMINANTS health. MRDLGs do not reflect
the benefits of the use of
Total Coliforms(%Positive each month) 5 0 0 0 2016 No Naturally present in environment disinfectants to control
microbial contaminants.
E.Coli(%Positive) 0 0 0 0 2016 No Human and animal fecal matter MRDL Maximum Residual
Heterotrophic Plate Count or HPC(CFU) NA 0.2 ND 0.8 2016 No NA Disinfectant Level:The highest
eTurbidity(NTU)The Turbidity limit for the 5 0.10 0.04 0.26 2016 No Soil runoff il of a dwnfe.The allowed
highest single measurement. inn d drinking waterr.There is
convincing evidence that
addition of a disinfectant is
INORGANIC CONTAMINANTS MCLG/PHG AL 90TH SAMPLE #SAMPLES EXCEEDS TYPICAL SOURCE necessary for control of
PERCENTILE DATE EXCEEDING AL AL microbial contaminants.
Lead-action level at consumer taps(ppb) ND 15 ND 2014 0 No Corosion of household plumbing systems; MNR Monitored Not
Erosion of natural deposits Regulated
Copper-action level at consumer taps(ppb) ND 1,300 71 2014 0 No Internal corrosion of household plumbing MPL Maximum Permissible
systems;erosion of natural deposits; Level:As determined by the
leaching from wood preservatives state of California
ADDITIONAL CONTAMINANTS UNITS STATE MCL AVERAGE VIOLATION SAMPLE DATE EXPLANATION AND COMMENT UNIT DESCRIPTIONS
pg/L:Micrograms per Liter, or
Alkalinity,Total ppm NA 53 No 2016 Erosion of natural deposits parts per billion
Aluminum ppb 1,000 21 No 2014 Erosion of natural deposits mg/L:parts per million
Barium ppb 2,000 12 No 2016 Erosion of natural deposits ppm: Parts per million, or
milligrams per Liter (mg/L)
Bromide ppm NA 0.02 No 2016 Erosion of natural deposits ppb: Parts per billion, or
micrograms per Liter (Ng/L)
Calcium ppm NA 12.6 No 2016 Erosion of natural deposits ppt: Parts per trillion, or
Carbon Dioxide,Free ppm NA 15.2 No 2016 Naturally occuring nanograms per Liter
ppq: Parts per quadrillion, or
Chloride ppm 500 10.4 No 2016 Erosion of natural deposits picograms per Liter
pCi/L: Picocuries per Liter (a
Chlorine,Free ppm 4 0.61 No 2016 By-product of disinfection process measure of radioactivity)
Chromium 6 ppb NA 0.42 No 2015 Erosion of natural deposits MFus Million Fibers per Liter,
used to measure asbestos
Color Units 15 5 No 2016 Naturally occurring organic materials concentration
NTU: Nephelometric Turbidity
Copper ppb NA 2 No 2016 Old plumbing/erosian of natural deposits Units. Turbidity is a measure
of the cloudiness of the
Dissolved Solids,Total ppm 1,000 100 No 2016 Erosion of natural deposits water. We monitor it
because it is a good
Electrical Conductance pS/cm 1,600 149 No 2016 Erosion of natural deposits indicator of the effectiveness
of our filtration system.
Hardness ppm NA 45 No 2016 Erosion of natural deposits positive samples/month:
The number of samples
Iron ppb 300 ND No 2016 Erosion of natural deposits taken monthly that were
found to be positive
Lead ppb NA 0.5 No 2016 Old plumbing/erosian of natural deposits positive samples/yr:The
number of positive samples
Magnesium ppm NA 2.6 No 2016 Erosion of natural deposits taken that year
Manganese ppb 50 2 No 2016 Erosion of natural deposits %positive samples/
month: Percentage of
Odor-Threshold Units 3 1 No 2016 Naturally occurring organic materials samples taken monthly that
were positive
ortho-Phosphate,as P ppm NA 0.04 No 2016 Erosion of natural deposits CFU/ml:Colony Forming Units
per milliliter
Phosphorus,Total ppm NA 0.05 No 2016 Erosion of natural deposits NA: Not Applicable
pH Units NA 7.68 No 2016 Erosion of natural deposits ND: Not Detected
NR: Not Required, but
Potassium ppm NA 1.5 No 2016 Erosion of natural deposits recommended
Radon pCi/L NA 243 No 2016 Erosion of natural deposits
Silver ppb 100 ND No 2016 Erosion of natural deposits
Sulfate ppm 500 ND No 2016 Erosion of natural deposits
Temperature-System °F NA 50.4 No 2016 Erosion of natural deposits
Vanadium ppb NA 3.6 No 2014 Erosion of natural deposits
Zinc ppb 5,000 ND No 2016 Runoff/leaching from natural deposits
ADDITIONAL MONITORING As part of an on-going evaluation CONTAMINANTS/PARAMETERS UNITS AVERAGE MINIMUM MAXIMUM SAMPLE DATE
program called UCMR-3 (unregulated contaminant monitoring rule
3), the EPA has required us to monitor some additional Chlorate ppm 0.083 ND 0.440 2/2015
contaminants/chemicals. Information collected through the Chromium,Total ppb 0.52 ND 1.30 2/2015
monitoring of these contaminants/chemicals will ensure that future
decisions on drinking water standards are based on sound science. Chromium-6 ppb 0.43 0.09 1.10 2/2015
The US EPA uses the UCMR to collect data for contaminants Cobalt ppb ND ND ND 2/2015
suspected to be present in drinking water to help determine if
drinking water standards need to be developed in the future.The Molybdenum ppb 13.8 ND 65 2/2015
District is required to monitor 28 chemical contaminants. The first
round was completed in August 2014. The second and final round Strontium ppb 124 15 330 2/2015
was conducted in February 2015. In the absence of identifiable
industrial sources other than chlorate, these contaminants are Vanadium ppb 3.6 ND 13 2/2015
naturally occurring in our watersheds. Chlorate is a degradation
product of the disinfectant used by STPUD for water disinfection and
is a common contaminant found in water treatment facilities
throughout the nation.