The City of San Diego

Water - A Branch of Public Utilities

Water Quality Data

Primary Standards (Mandatory Health Related Standards)

Fluoride:

California state law requires water agencies with more than 10,000 water service connections to fluoridate their drinking water. In February 2011, the City of San Diego's water treatment plants began this state-mandated fluoridation. For more information, visit www.sandiego.gov/water/quality/fluoridation.shtml.

San Diego's source waters contain naturally occurring fluoride at levels that range from 0.2 to 0.6 ppm. State regulations require the fluoride levels in the treated water be maintained within a range of 0.6 - 1.2 ppm with an optimum dose of 0.7 ppm. Our water system treats your water by adding fluoride to the naturally occurring level to help prevent dental caries in consumers. Our monitoring showed fluoride levels in the treated water ranging from 0.4 to 1.0 ppm, with average values of 0.6 - 0.8 ppm. Information about fluoridation, oral health, and current issues is available from www.cdph.ca.gov/certlic/drinkingwater/Pages/Fluoridation.aspx.

CHEMICAL PARAMETERS UNITS MCL PHG (MCLG) CDPH DLR CITY OF SAN DIEGO TREATMENT PLANTS MWD SKINNER TREATMENT PLANT MAJOR SOURCES
IN DRINKING WATER
ALVARADO MIRAMAR OTAY
AVERAGE RANGE AVERAGE RANGE AVERAGE RANGE AVERAGE RANGE
Fluoride (naturally occurring) ppm 2 1 0.1 0.2 0.2 - 0.3 0.3 0.2 - 0.4 0.4 0.3 - 0.6 0.3 0.1 - 0.3 Erosion of natural deposits
Fluoride (treatment-related) ppm 2 1 0.1 0.8 0.7 - 0.9 0.8 0.7 - 1.0 0.6 0.4 - 0.8 0.8 0.7 - 1.0 Water additive that
promotes strong teeth
Note: Optimal Fluoride Level = 0.7 ppm; Control Range = 0.6 - 1.2 ppm

Radioactive Parameters:

As water travels over the surface of the land or through the ground, it dissolves naturally occurring minerals and, in some cases, radioactive material. Radioactive contaminants can be naturally occurring or be the result of oil and gas production and mining activities.

Regulations require that the City of San Diego monitor for Radioactive Parameters every three years. The results in this report are presented in units of pCi/L, or picocuries per liter; this represents an amount of radiation. Our results are significantly below the MCL for all radioactive parameters.

RADIOACTIVE PARAMETERS UNITS MCL PHG (MCLG) CDPH DLR CITY OF SAN DIEGO TREATMENT PLANTS MWD SKINNER TREATMENT PLANT MAJOR SOURCES
IN DRINKING WATER
ALVARADO MIRAMAR OTAY
AVERAGE RANGE AVERAGE RANGE AVERAGE RANGE AVERAGE RANGE
Gross Alpha Particle Activity pCi/L 15 (0) 3 4.6 n/a ND n/a ND n/a ND ND - 3 Erosion of natural deposits
Gross Beta Particle Activity pCi/L 50* (0) 4 ND n/a ND n/a ND n/a ND ND - 5 Decay of natural and manmade deposits
Uranium pCi/L 20 0.43 1 2.4 n/a 1.7 n/a 1.2 n/a 1 ND - 2 Erosion of natural deposits
Note: Regulations require monitoring every three years. Most recent monitoring: 2013 for Alvarado, 2012 for Miramar and Otay, 2011 for MWD Skinner. * CDPH considers 50 pCi/L to be the level of concern for beta particles.

Total Coliform Bacteria:

Coliforms are bacteria that are naturally present in the environment and are used as an indicator that other, potentially harmful bacteria may be present. The CDPH regulations require the City to test a minimum of 85 samples per week from throughout the distribution system for total coliform and E.coli, and to report the results, including the percentage of total Coliform positive samples in a given month. To meet this requirement, in 2013 the City of San Diego collected and analyzed 6,826 samples from the distribution system (an average of 131 per week) for total coliform and E. coli. The MCL is 5.0%; this means that if more than 5.0% of the monthly samples collected are total coliform positive, then the MCL is violated. In 2013 the City did not exceed the monthly MCL for total coliform bacteria; our maximum was 0.8% of monthly samples. The regulations are written as a percentage of monthly samples because multiple variables can cause a positive result, including localized contamination at the tap. Each time any sample tests positive, three repeat samples are collected and the cause of the positive result investigated.

MICROBIOLOGICAL UNITS MCL PHG (MCLG) CDPH DLR CITY OF SAN DIEGO DISTRIBUTION SYSTEM MWD DISTRIBUTION SYSTEM MAJOR SOURCES IN DRINKING WATER
AVERAGE RANGE* AVERAGE RANGE
Total Coliform Bacteria /100ml < 5% Positive (0) n/a 0.2% 0 - 0.8% ND ND - 0.2% Naturally present
in the environment
*Based on Monthly Percentages of Positive Total Coliform samples

Turbidity:

Turbidity is a measure of the cloudiness of the water. We monitor it because it is a good indicator of the effectiveness of our filtration system. San Diego's three water treatment plants monitor for turbidity every 15 minutes to ensure uniform quality of water produced for our customers. Our consistently very low turbidity results attest to the high quality of drinking water produced and have led to our treatment plants receiving awards for quality - for example Otay Treatment Plant has been awarded the Directors Award for six consecutive years from the American Water Works Association (AWWA) Partnership for Safe Water (PSW) Program; Miramar has two years of Directors Award and is one of only six plants nationwide to receive the Presidents Award from the PSW; and Alvarado Treatment Plant recently received the American Society of Civil Engineers award for innovation in plant design and continuous operation during upgrade, and participates in the Partnership for Safe Water program.

TURBIDITY UNITS MCL PHG (MCLG) CITY OF SAN DIEGO TREATMENT PLANTS MWD SKINNER TREATMENT PLANT MAJOR SOURCES IN DRINKING WATER
ALVARADO MIRAMAR OTAY
Turbidity NTU TT = 1 NTU n/a Max Level Found = 0.11 Max Level Found = 0.14 Max Level Found = 0.13 Max Level Found = 0.09 Soil runoff
Turbidity NTU TT = 95% of samples =0.3NTU n/a 100% of samples = 0.3 NTU 100% of samples = 0.3 NTU 100% of samples = 0.3 NTU 100% of samples = 0.3 NTU Soil runoff

Lead and Copper:

Lead and copper enter drinking water primarily through plumbing materials. Exposure to lead and copper may cause health problems ranging from stomach distress to brain damage. In 1991, the EPA published the Lead and Copper Rule to control lead and copper in drinking water. The rule requires us to monitor drinking water at customer taps. If lead concentrations exceed an action level of 15 ppb or copper concentrations exceed an action level of 1.3 ppm in more than 10% of taps sampled, we would be required to undertake a number of additional actions to inform the public and control corrosion.

In 2011, fifty customers provided samples from their taps to the City of San Diego for lead and copper analysis. The results of these tests are presented here. Because less than 10% of our results were above the Action Levels for Lead and Copper, no additional actions were required. Lead and Copper Rule monitoring must be conducted every three years - our next study will be conducted in 2014.

Infants and young children are typically more vulnerable to lead in drinking water than the general population. It is possible that lead levels at your home may be higher than at other homes in the community as a result of materials used in your home's plumbing. If you are concerned about elevated lead levels in your home's water, you may wish to have your water tested and/or flush your tap for 30 seconds to two minutes before using tap water. Additional information is available from the USEPA Safe Drinking Water Hotline (1-800-426-4791).

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in drinking water is primarily from materials and components associated with service lines and home plumbing. The City of San Diego is responsible for providing high-quality drinking water, but cannot control the variety of materials used in plumbing components. When your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to two minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline or at www.epa.gov/safewater/lead.

LEAD AND COPPER STUDY UNITS ACTION LEVEL PHG (MCLG) CDPH DLR SAMPLES TAKEN FROM CUSTOMER TAPS MAJOR SOURCES IN DRINKING WATER
90th PERCENTILE CONCENTRATION SAMPLING SITES NUMBER EXCEEDING AL VIOLATION
Copper ppm 1.3 0.3 0.050 0.309 50 0 NO Internal corrosion of household plumbing systems
Lead ppb 15 0.2 5 ND 50 3 NO Internal corrosion of household plumbing systems
Note: Monitoring mandated every three years. Most recent monitoring conducted in 2011.