2020 South Tahoe Public Utility District
CONSUMER CONFIDENCE REPORT 2020
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IS MY WATER SAFE?Yes. Last year, as in years Department of Public Health (CDPH). domestic wastewater discharges, oil and gas encourages our customers to attend, ask
past,your tap water met all U.S. Environmental You may view the document by visiting the production, mining, or farming. Pesticides and questions, and provide feedback.
Protection Agency(EPA) and state drinking District's website at www.stpud.us or by herbicides, may come from a variety of sources RESULTS OF RADON MONITORING Radon is a
water health standards.The South Tahoe Public requesting a copy by calling Customer Service such as agriculture, urban stormwater runoff,
Utility District vigilantly safeguards its water at 530-544-6474. and residential uses. Organic chemical radioactive gas that cannot be seen, tasted or
supplies and we are proud to report that our The District has an ongoing drinking water contaminants, including synthetic and volatile smelled. It is found throughout the U.S. Radon
system has not violated a maximum contaminant source development program that seeks potential organic chemicals, are by-products of industrial can move up through the ground and into a
level or any other water quality standard. drinking water well locations. Due to the volume processes and petroleum production, and can home through cracks and holes in the
foundation. Radon can build up to high levels in
of the average annual Sierra snowpack and also come from gas stations, urban stormwater
DO I NEED TO TAKE SPECIAL PRECAUTIONS? all types of homes. Radon can also get into
Lake Tahoe itself, our aquifer has a significant runoff, agricultural application and septic
Some people may be more vulnerable to indoor air when released from tap water from
recharge capability. The District continues to systems. Radioactive contaminants can be
contaminants in drinking water than the showering,washing dishes, and other
work diligently to protect and maintain this naturally occurring or be the result of oil and
general population. Immuno-compromised household activities. Compared to radon
precious natural resource. gas production and mining activities. In order to
persons such as persons with cancer undergoing entering the home through soil, radon entering
ensure that tap water is safe to drink, the United
chemotherapy, persons who have undergone WHY ARE THERE CONTAMINANTS IN MY the home through tap water will, in most cases,
organ transplants, people with HIV/AIDS or DRINKING WATER?Drinking water, including States Environmental Protection Agency(Health be a small source of radon in indoor air. Radon
other immune system disorders, some elderly, bottled water, may reasonably be expected to and the California Department of Public Health is a known human carcinogen. Breathing air
and infants can be particularly at risk from contain at least small amounts of some (DPH) prescribe regulations that limit the amount containing radon can lead to lung cancer.
infections.These people should seek advice contaminants.The presence of contaminants of certain contaminants in water provided by Drinking water containing radon may also cause
public water systems. Food and Drug
about drinking water from their health care does not necessarily indicate that water poses a increased risk of stomach cancer. If you are
providers. EPA/Centers for Disease Control health risk. More information about Administration (FDA) regulations establish limits concerned about radon in your home, test the
CDC guidelines on a ro riate means to contaminants and potential health effects can be for contaminants in bottled water which must air in your home. Testingis inexpensive and
lessen the risk of infection by Cryptosporidium obtained by calling the Environmental Protection provide the same protection for public health. easy. Fix your home if the level of radon in your
and other microbial contaminants are available Agency's (EPA) Safe Drinking Water Hotline HOW CAN I FIND OUT MORE?The information air is 4 picocuries per liter of air (pCi/L) or
from the USEPA's Safe Water Drinking Hotline (1-800-426-4791). The sources of drinking contained in the Consumer Confidence Report higher. There are simple ways to fix a radon
(1-800-426-4791). water(both tap water and bottled water) include may not answer all the questions you may have problem that aren't too costly. For additional
WHERE DOES MY WATER COME FROM?There rivers, lakes, streams, ponds, reservoirs, springs, about the quality of the South Tahoe Public information, call your state radon program or
are 11 active drinking water wells and 4 and wells.As water travels over the surface of Utility District's drinking water supply. The call EPA's Radon Hotline
standby wells which supply more than 14,000 the land or through the ground, it dissolves District welcomes public participation in (800-SOS-RADON).
naturally occurring minerals and, in some cases, developing water quality policy. If you would
homes and businesses. All our drinking water is RESULTS OF VOLUNTARY MONITORING
radioactive material, and can pick up like more detailed information, please call the
pumped from underground aquifers. No water See data sheets.
substances resulting from the presence of District Laboratory at 530-544-6474 extension
is taken from Lake Tahoe or any other surface
animals or from human activity. Microbial 6231, or check our website at www.stpud.us. REGARDING ARSENIC Arsenic is a naturally
water source.
contaminants, such as viruses and bacteria, may The District is governed by an elected five- occurring substance that is sometimes found at
SOURCE WATER ASSESSMENT AND come from sewage treatment plants, septic member Board of Directors. Board meetings are very low levels in drinking water, primarily
PROTECTION The District's Groundwater systems, agricultural livestock operations, and held on the first and third Thursday of each groundwater. The South Tahoe Public Utility
Management Plan (California Water Code wildlife. Inorganic contaminants, such as salts month at 2 p.m. at the Customer Service Facility District has an active Arsenic monitoring
Section 10750)was adopted on December 4, and metals, can be naturally occurring or result located at 1275 Meadow Crest Drive. All program, as well as a pilot Arsenic removal
2014 and is on file with the California from urban stormwater runoff, industrial, or meetings are open to the public and the District system in one of its wells.
SPANISH(ESPANOL)Este informe contiene informacion muy importante sobre la calidad de su agua de beber. Por favor hagalo traducir 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 which we calendar year of the report.The EPA or the State the safest water possible, the State has required us to DEFINITIONS
detected which are applicable for the calendar year requires us to monitor for certain contaminants less monitor some contaminants not required by Federal MCL Maximum Contaminant
of this report. The presence of contaminants in the than once per year because the concentrations of regulations. Of those contaminants only the ones Level:The highest level of a
water does not necessarily indicate that the water these contaminants do not change frequently. listed on the last page under"Additional contaminant that is allowed in
drinking water. MCLs are set as
poses a health risk. Unless otherwise noted, the data Contaminants"were found in your water. close to the MCLGs as feasible
using the best available
treatment technology.
MCLG/PHG MCL OR MRDL AVERAGE MIN MAX SAMPLE VIOLATION TYPICAL SOURCE MCLG Maximum Contaminant
OR MRDLG DATE Level Goal: The level of a
MICROBIOLOGY contaminant in drinking water
below which there is no known
A total of 1,087 Coliform and E.coli or expected risk to health.
bacteria samples taken throughout our MCLGs allow for a margin of
distribution system,as part of our safety.
routine monitoring,in 2020. MPL Maximum Permissible
Total Coliforms(%Positive each month) 0 5 0 0 0 2020 No Naturally present in environment Level:As determined by the
E.coli(%Positive) 0 0 0 0 0 2020 No Human and animal fecal matter state of California
MRDL Maximum Residual
Heterotrophic Plate Count or HPC(CFU) 200 NA 1.5 ND 6 2020 No Naturally present in environment Disinfectant Level:The highest
Temperature-System(°F) NA 50 36 68 2020 No level of a disinfectant allowed
in drinking water.There is
Turbidity(NTU)The Turbidity limit for 1 5 0.15 0.05 0.49 2020 No Soil runoff convincing evidence that
the highest single measurement. addition of a disinfectant is
necessary for control of
INORGANIC CONTAMINANTS microbial contaminants.
Arsenic(ppb) 0.004 10 3.4 ND 9.0 2020 No Erosion of natural deposits;Runoff MRDLG Maximumel Residual
from orchards;Runoff from glass and level
l ofo a drinkingn Lo Goal:The
electronics production wastes level c a water
disinfectant below which there
Fluoride(ppm) 1 2 0.08 ND 0.15 2020 No Erosion of natural deposits; is no known or expected risk to
Discharge from fertilizer and aluminum health. MRDLGs do not reflect
factories the benefits of the use of
disinfectants to control
Nitrate[measured as Nitrogen](ppm) 10 10 0.20 0.01 0.56 2020 No Runoff from fertilizer use;Leaching from microbial contaminants.
septic tanks,sewage;Erosion of natural
deposits PDWS Primary Drinking Water
Standards: MCLs for
Sodium(ppm) NA NA 12.0 5.0 31.0 2020 No Erosion of natural deposits;Leaching contaminants that affect health
along with their monitoring and
RADIONUCLEIDES reporting requirements, and
water treatment requirements.
Gross Alpha(pCi/L),minus Uranium 15 4.9 0.01 10.4 2020 No Erosion of natural deposits PHG Primary Health Goal:The
Uranium(pCi/L) 0.4 20 4.6 ND 15.1 2020 No Erosion of natural deposits level of contaminant in drinking
wRadium-226(pCi/L) 0.05 ND ND 0.9 2019 No Erosion of natural deposits is noor knownbelow below expectedwdh there
to
p° is or risk to
Radium-228(pCi/L) 0.02 ND ND ND 2019 No Erosion of natural deposits health. PHGs are set by the
California Environmental
Radium-226+Radium-228(pCi/L) 5 ND ND 0.9 2019 No Erosion of natural deposits Protection Agency.
Radon(pCi/L) NA 4,000 484 ND 2,060 2020 No Erosion of natural deposits
VOLATILE ORGANIC CHEMICALS
MTBE[Methyl Tert Butyl Ether] (ppb) 5 13 ND ND ND 2020 No Leaking underground fuel storage tanks
Total Trihalomethanes(ppb) NA 80 1.1 ND 5.0 2020 No By-product of drinking water disinfection
HaloAcetic Acids(ppb) NA 60 0.1 ND 1.2 2020 No By-product of drinking water disinfection
1,2,3-TCP(ppb) 0.0007 0.005 ND ND ND 2019 No By-product of drinking water disinfection
INORGANIC CONTAMINANTS MCLG/PHG AL 90TH SAMPLE #SAMPLES EXCEEDS TYPICAL SOURCE UNIT DESCRIPTIONS
PERCENTILE DATE EXCEEDING AL AL
Ng L:Micrograms per Liter, or
Lead-action level ND 15 2.8 2020 0 No Corosion of household plumbing systems; parts per billion
at consumer taps(ppb) Erosion of natural deposits mg/L:Milligrams per liter or
parts per million
Copper-action level ND 1,300 394 2020 0 No Internal corrosion of household plumbing
at consumer taps(ppb) systems;erosian of natural deposits; ppm: Parts per million, or
leaching from wood preservatives milligrams per Liter (mg/L)
ppb: Parts per billion, or
ADDITIONAL CONTAMINANTS UNITS STATE MCL AVERAGE MAXIMUM VIOLATION SAMPLE DATE COMMON SOURCE micrograms per Liter (pg/L)
Alkalinity-Total ppm NA 52.2 65.5 No 2020 Erosion of natural deposits pCi/L: Picocuries per Liter(a
measure of radioactivity)
Aluminum ppb 1,000 ND ND No 2020 Erosion of natural deposits MFL:Million Fibers per Liter,
Asbestos(fibers exceeding 0.01mm) MFL 7 ND ND No 2015 Erosion of nat deps/industrial discharge used to measure asbestos
Barium ppb 1,000 12 42.4 No 2020 Erosion of natural deposits concentration
NTU: Nephelometric Turbidity
Bromide ppm NA 0.01 0.04 No 2020 Erosion of natural deposits Units. Turbidity is a measure
Calcium ppm NA 14.9 22.3 No 2020 Erosion of natural deposits of the cloudiness of the
water.
Carbon Dioxide,Free ppm NA 6.2 28.5 No 2020 Naturally occuring CFU/ml:Colony Forming Units
Chloride ppm 500 10.7 59.8 No 2020 Erosion of natural deposits per milliliter
Chlorine,Free ppm 4 0.55 1.11 No 2020 By-product of disinfection process NA: Not Applicable
Chromium ppb 50 1.08 1.36 No 2020 By-product of disinfection process ND: Not Detected
Chromium 6 ppb NA 0.42 1.3 No 2015 Erosion of nat deps/industrial discharge
Color Units 15 ND ND No 2020 Naturally occurring organic materials
Copper ppb 1,000 2.4 5.75 No 2020 Old plumbing/erosian of natural deposits
Dissolved Solids,Total ppm 1,000 97 190 No 2020 Erosion of natural deposits
Electrical Conductance pS/cm 1,600 139 287 No 2020 Erosion of natural deposits
Hardness ppm NA 42 71 No 2020 Erosion of natural deposits
Iron ppb 300 ND 25.6 No 2020 Erosion of natural deposits
Lead ppb 15 ND ND No 2020 Old plumbing/erosian of natural deposits
Magnesium ppm NA 2.4 6.2 No 2020 Erosion of natural deposits
Manganese ppb 50 ND 3.7 No 2020 Erosion of natural deposits
Mercury ppb 2 ND ND No 2020 Erosion of natural deposits
Nickel ppb 100 ND ND No 2020 Erosion of natural deposits
Odor-Threshold Units 3 ND ND No 2020 Naturally occurring organic materials
Perchlorate ppb 6 ND ND No 2019 Industrial discharge
ortho-Phosphate,as P ppm NA 0.04 0.13 No 2020 Erosion of natural deposits
Phosphorus-Total ppm NA 0.04 0.13 No 2020 Erosion of natural deposits
pH Units NA 8.1 6.6 and 9.2 No 2020 Erosion of natural deposits
Potassium ppm NA 1.4 4.4 No 2020 Erosion of natural deposits
Selenium ppb 50 ND ND No 2020 Erosion of natural deposits
Silver ppb 100 ND ND No 2020 Erosion of natural deposits
Sulfate ppm 500 3.3 5.9 No 2020 Erosion of natural deposits
Thallium ppb 2 ND ND No 2020 Erosion of natural deposits
Vanadium ppb NA 4.0 7.1 No 2020 Erosion of natural deposits
Zinc ppb 5,000 ND ND No 2020 Runoff/leaching from natural deposits
SOCs (Synthetic Organic Compounds) are man-made carbon based SOC RESULTS AVERAGE MINIMUM MAXIMUM SAMPLE DATE
chemicals.They are used as pesticides, defoliants, fuel additives and
as ingredients in the manfacture of many other compounds. Some of EPA 505-Organochlorine Pesticides/PCBs ND ND ND 11/2018
the more well known ones include PCBs,Atrazine, Florene, Dioxins EPA515.4-ChlorophenoxyHerbicides ND ND ND 11/2018
and Caffeine. SOC's health effects include damage to the nervous
system and cancer risks. The District last tested for these chemicals in EPA 551.1 -EDB/DBCP/HAN ND ND ND 11/2018
2018. EPA 525.2-Semivolatiles ND ND 1.3 ppb* 11/2018
EPA 548.1 -Endothall ND ND ND 11/2018
EPA 1613E-2,3,7,8-TCDD_Dioxin ND ND ND 11/2018
EPA 547-Glyphosate ND ND ND 11/2018
EPA 531.2-Aldicarbs ND ND ND 11/2018
EPA 549.2-Diquat and Paraquat ND ND ND 11/2018
EPA 524M-TCP-1,2,3 Trichloropropane ND ND ND 11/2018
*1.3 parts per billion Di(2-Ethylhexyl)phthalate) MCL=4 parts per billion
ADDITIONAL MONITORING As part of an on-going evaluation UCMR-3 RESULTS UNITS AVERAGE MINIMUM MAXIMUM SAMPLE DATE
program called UCMR(Unregulated Contaminant Monitoring Rule),
the Environmental Protection Agency requires the District to monitor a Chlorate ppm 0.083 ND 0.440 2/2015
number of additional contaminants/chemicals. Information collected Chromium,Total ppb 0.52 ND 1.30 2/2015
through this monitoring provides information for future decisions on
drinking water standards. Chromium-6 ppb 0.43 0.09 1.10 2/2015
UCMR-3 STPUD was required to monitor our source water for 28 Cobalt ppb ND ND ND 2/2015
chemical contaminants. The first round was completed in August Molybdenum ppb 13.8 ND 65 2/2015
2014 and the second round in February 2015. In the absence of
identifiable industrial sources, these contaminants are naturally Strontium ppb 124 15 330 2/2015
occuring in our watershed. Chlorate is an exception and is a Vanadium ppb 3.6 ND 13 2/2015
degradation product of the disintectant used by the District for
drinking water.
UCMR-4 In this round of UCMR, STPUD was required to monitor for
18 chemical contaminants, as well as the Total Organic Carbon
(TOC) content in our Source Water. The first round was completed in UCMR-4 RESULTS UNITS AVERAGE MINIMUM MAXIMUM SAMPLE DATE
January 2019 and the second round in July 2019.These
contaminants included metals like Germanium, volatile Pesticides and Total Haloacetic Acids HAA9 ppb 0.5 ND 4.2 1/2019,7/2019
their byproducts such as alpha-HCH,volatile Alcohols like 1-Butanol
and Tar/Oil byproducts like Quinoline. TOC ppm 0.3 ND 0.5 1/2019,7/2019
We also tested our Distribution System for 9 Disinfection byproducts Germanium ppb ND ND ND 1/2019,7/2019
collectively known as Haloacetic Acids (HAA9). alpha-HCH ppb ND ND ND 1/2019,7/2019
Quinoline ppb ND ND ND 1/2019,7/2019
1-Butanol ppb ND ND ND 1/2019,7/2019