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2005 Consumer Confidence Report Of Water Quality

2005 Consumer Confidence Report of Water Quality
To Our Water Customers, June, 2006 
The City of Daly City is pleased to present to you, our customers, the 2005 Consumer Confidence Report (CCR). We want you to know about the City’s water supply; where it comes from, how it is handled to insure your health and safety, upcoming changes to the system and the results of ongoing water quality monitoring.
Top Quality Water Resource
Your drinking water is top quality and undergoes a rigorous monitoring program to comply with prescribed regulations, as mandated by the State Department of Health Services (DHS) and EPA standards. The water delivered to your home, business or school is safe and of high quality. Only under rare circumstances specifically involving persons with identified health concerns, such as being on dialysis or having significantly compromised immune systems, is there a need for specially treated, filtered or prepared water. There is more technical information regarding our monitoring and water quality results later in this report.

Contacts for your Questions
If you have any questions regarding your water bill, water quality, or this report, please use the following numbers to get answers to your inquiries.

For any questions concerning your bill, starting or stopping service, contact Utility Billing at: (650) 991-8082

To report a leak or other problems (24 hours a day), obtain water quality information or other technical data, or to ask any water related questions, please call the Water and Wastewater Resources Department: (650) 991-8200

The main contact person for water quality information issues, or for anything specifically related to this report, is the Director of Water and Wastewater Resources Patrick Sweetland, who my be reached at: (650) 991-8200

How The Public Can Be Involved

Meetings of the City Council of the City of Daly City begin at 7:00 pm on the second and fourth Monday of each month and are open to the public. Meetings are held in the City Council Chamber located on the second floor of the Daly City Civic Center, 333-90th Street.

We welcome your comments and suggestions on how to improve our water system or methods to better preserve our resources. Contact Patrick Sweetland of the Department of Water and Wastewater Resources for information regarding future public meetings, to voice concerns regarding service or delivery of your water.

Important consumer information is also available on Daly City’s website at: www.dalycity.org.


The City of Daly City has successfully converted the drinking water disinfectant from chlorine to chloramine. The conversion took place during the first week of February 2004.

Converting to chloramine allows the City to provide water that meets the stringent drinking water standards for disinfection byproducts, specifically the federal and state Disinfectant/Disinfection Byproducts Rule (D/DBP Rule). Chloramine, a combination of 5 parts chlorine and 1 part ammonia, is a more stable disinfectant, lasts longer in water, and produces lower levels of disinfection byproducts called trihalomethanes (TTHMs) and halacetic acids (HAA5s), suspected carcinogens. While the current standard is a maximum TTHM level of 80 parts per billion, Daly City water currently tests at 30.4 parts per billion. This represents a decrease by over 50% compared with last year when our water tested at 70.5 parts per billion. And HAA5s currently test at 19.2 parts per billion, well below the standard of 60 parts per billion.

According to the EPA, approximately one-third of all water suppliers in the United States are using chloramine as a drinking water disinfectant. Local agencies include the East Bay Municipal Utility District, Alameda County Water District, Santa Clara Valley Water District, Contra Costa Water District and Marin Municipal Water District. The city of Denver, Colorado, has chloraminated their water supply for 90 years. Everything we know about chloramine points to the fact that it enhances public safety in the drinking water supply.

An operational consideration associated with the use of chloramination is to avoid stagnant water within the system. Chloramination retains a modal contact time of up to 28 days. Stagnant water increases the possibility of taste and odor complaints associated with nitrification.

Part of the City’s response to the chloramine conversion involved a citywide flushing program completed in Fall 2003. The flushing program will become an annual program to clear out naturally occurring sediment from water mains. Crews flush the system by exercising fire hydrants throughout local neighborhoods. Residents will receive advanced flyers announcing when flushing will occur in their area. In addition to clearing water lines, the flushing program enables staff to better assess the condition of water valves in the system and fire flows throughout the community.

Just as they had with chlorine, three groups need to take precautions with chloramine. Those groups include kidney dialysis patients, owners of fish, amphibians and reptiles that live in water, and businesses requiring highly processed water.

Owners of fish, amphibians and reptiles can utilize special treatment methods, either drops or tablets, or a biological filter combined with a chemical agent to neutralize chloramine. However, these same precautions need not be taken for any other household use of drinking water. Chloraminated water is safe for people and animals to drink, cook with, bathe in, and for all other general uses. Again, the three groups mentioned above will not be doing anything different by removing the drinking water disinfectant prior to use; they will now just use a different method of removal.

Where Your Water Comes From
The Daly City water system is supplied about equally from two sources, the San Francisco Water Department and local Daly City wells. San Francisco is supplied exclusively by their surface water system which is mostly reliant on the Hetch Hetchy Watershed, and to a lesser degree local reservoirs.
Hetch Hetchy Watershed

The Hetch Hetchy watershed is a 459 square mile area located in Yosemite National Park at the headwaters of the Tuolumne River. It provides approximately 80 percent of the San Francisco Public Utilities Commission (SFPUC) supply.

The Hetch Hetchy system captures water inflows from the watershed in the Hetch Hetchy Reservoir. This reservoir, the primary source for the system, is filled by spring snowmelt, runoff and the Tuolumne River. Water in the Hetch Hetchy Reservoir is treated but not filtered because it is of such high quality.

Alameda and Peninsula Watersheds

The Alameda and Peninsula watersheds provide the remaining 20 percent of the SFPUC water system. The Alameda watershed is located in the East Bay, and represents about ten percent of the total water supply, with water captured and stored in two reservoirs: Calaveras and San Antonio.

The Peninsula watershed, representing the remaining ten percent of the SFPUC supply, captures runoff in four reservoirs, Crystal Springs, San Andreas and the smaller Pilarcitos and Stone Dam reservoirs.

The six reservoirs in the Alameda and Peninsula watersheds capture rain, local runoff and some also store Hetch Hetchy water for use by the SFPUC. Water from the Hetch Hetchy Reservoir that is stored locally is treated and filtered, as is any local water source.

Daly City’s Wells (Groundwater)

The SFPUC water supply is contained in surface water reservoirs. The term “surface water” refers to water that is collected at ground level. Wells comprise what is termed “groundwater”, or water that is stored below the earth’s surface. When we are not in a conjunctive use agreement, about half of the water served by the Daly City Water System is from local wells.

Daly City completed a source water assessment of its local groundwater sources in 2003. Groundwater in many ways is a much more protected source than surface water. We draw water from an average depth of 300 feet below ground from a large aquifer known as the Westside Basin that serves a large portion of the northern San Mateo Peninsula and extends north to Golden Gate Park in San Francisco. Because of its protected environment and the consistency of our monitoring results, our well water is only required to have a disinfectant added to it prior to being served in our system.

It should be noted that the City’s wells are checked regularly for bacteriological levels, and the nonchlorinated/untreated well water is consistently determined to have a rating of “non-detect” for any coliform organisms. Daly City well water is blended with San Francisco water and then distributed throughout the community.

Results from nitrate testing showed detected amounts of nitrate in excess of the MCL of 45 mg/L (ppm) at Well #4 and A Street Well, but the blended average in the distribution system was 1.23 mg/L. Nitrate is one of the major anions in natural water, but concentrations can be greatly elevated due to leaching of nitrogen from fertilizers.

While there are no significant health effects of nitrate levels in your tap water due to blending, additional information is required because of the elevated findings in the well water and is not an indicator or statement of the quality of water distributed to you.

Conjunctive Use Term Agreement

Daly City entered into a conjunctive use program with the SFPUC with the goal of enhancing regional water resource management. The first phase of the project, which concluded in November 2003, took advantage of the availability of surplus SFPUC system water at a reduced rate. Daly City agreed to use more SFPUC system water and not pump groundwater from the Westside Basin. This action provided the opportunity to observe the response of the basin from recharge that takes place as a result of the reduction in groundwater pumping. The second phase of conjunctive use began in March 2004 and has continued into 2006.

The demonstration project was introduced to partially assess the feasibility of a permanent program, as tentatively outlined would: 1) increase groundwater levels in the Westside Basin, 2) reduce the potential for seawater intrusion, 3) develop increased SFPUC system yield from the overall surface and groundwater system, and 4) potentially improve conditions at Lake Merced. Initial results from this project show that groundwater levels have increased within the basin. 9,500 acre feet of additional water has been stored in the Basin, enough water to sustain 38,000 households for one year. Daly City has an added benefit of saving its local resource, resulting in enhanced emergency and drought protection.

Weekly Water Sampling by Certified City Water Operators

Daly City maintains 35 sampling sites located throughout the community that are tested weekly for microbiological contaminants. Tests are run by the City’s contract laboratory, EM Laboratory in San Bruno, for maximum contaminant levels of certain types of 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.

In 2005, certified Water Operators collected 1,278 samples of which there was one instance of a positive test for coliform that equates to just 0.08 percent of all samples taken. Upon re-sampling of the locations, all tests came back negative for coliform, and on no occasion did a test detect the presence of fecal coliform or E. Coli.

Lead and Copper
Lead in amounts in excess of established notification levels (previously called action levels) in drinking water can cause delayed physical and/or mental development in infants and attention span and learning deficits in children. In adults it can cause kidney problems and possible high blood pressure.

Because of these concerns the EPA mandated in 1993 that lead and copper monitoring be conducted by all water systems. Daly City completed the required monitoring and corrosion study in 1994. The results of the study were well under any notification levels and met all quality standards. Due to these favorable results, Daly City was reduced to triennial monitoring (every three years).

In 1998, under advisement from the EPA, DHS required local water systems to complete their studies. A joint effort was organized by the SFPUC for collection and analysis by the member agencies.

Since Daly City had previously conducted the study, an agreement was reached with DHS to do a special water quality study to determine the aggressiveness (corrosivity) of our well water and determine ways to meet the requirements for corrosion control in our water system.

The study was performed in September 1999, and the results of the second Daly City study showed results were again under any notification levels (0.015 mg/L for lead and 1.5 mg/L for copper) and met all quality standards. In December 2001, lead and copper samples were collected and this third Daly City study showed results remained under any notification levels.

The results of the second and third Daly City studies indicate that the well water blend with Hetch Hetchy supply provided a buffering effect, which lowered the corrosivity of the water. The fourth round of testing took place in August 2004 and test results for lead and copper were again well below notification levels. The 90th percentile was 0.0049 mg/L for lead and 0.086 mg/L for copper. None of the 52 homes tested at or above notification levels. Testing will take place again in 2007.

Microbiological Information
Monitoring for bacteriological constituents in the distribution system is required to determine the presence of microbiological contaminants such as coliforms, fecal coliforms, and E. Coli.
  Minimum number of monthly samples 100
  Maximum number of positive samples allowed (MCL) 5%
  Yearly number of samples taken 1,278
  Highest monthly number of positive coliform samples (May 2005) 1
  Total number of positive fecal coliform or E. Coli samples 0

Fluoridation Program
The San Francisco Public Utilities Commission (SFPUC) has fluoridated treated drinking water for more than 50 years. Beginning in June 2004, Daly City fluoridated the blended water supply throughout the entire community, in keeping with the optimum level of 1.0 mg/L (parts per million) established by the California State Department of Health Services (DHS).

Assembly Bill (AB) 733 authorizes the DHS to require large water systems to fluoridate their public water supply once funding became available. The City of Daly City entered into an agreement with the California Dental Association Research Fund, Inc. and was reimbursed slightly more than $115,000 for design, purchase and installation of equipment and for operation and maintenance expenses to augment fluoridation throughout our community.

How Drinking Water Sources Become Polluted

The sources of drinking water (both tap and bottled) include rivers, lakes, streams, ponds, reservoirs, springs and wells. As water travels over the surface of the land or through the ground, it dissolves naturally occurring minerals and in some cases even radioactive material. Surface waters in particular can be susceptible to substances resulting from the presence of animals or human activity. Contaminants that may be present in source waters include:

Microbial Contaminants such as viruses and bacteria that may come from septic systems, agricultural livestock operations and wildlife.

Inorganic Contaminants such as salts and minerals which can be naturally occurring or result from urban stormwater runoff, industrial or domestic wastewater discharges, oil and gas production, mining or farming.

Organic Chemical Contaminants including synthetic and volatile organics which are by-products of industrial processes and petroleum production and can also come from septic systems, urban stormwater runoff, and agricultural chemicals such as chemical fertilizers and gas stations.

MTBE, a gasoline additive, has become a recent water quality concern. This organic contaminant has rapidly been made a primary contaminant by DHS and is regularly monitored. All test results for MTBE in the City’s wells and distribution system have been rated “non-detect”.

Radioactive Contaminants which can be naturally occurring, or the result of oil and gas production and mining activities.

Pesticides and Herbicides may come from a variety of sources such as agriculture, urban stormwater runoff and residential uses.

Unregulated Contaminant Monitoring helps the U.S. EPA and the State Department of Health Services (DHS) to determine where certain contaminants occur and whether the contaminants need to be regulated.

During 2000, the SFPUC monitored for twelve unregulated contaminants including MTBE, perchlorate, herbicides, and pesticides. These contaminants were not detected in any of Daly City’s or SFPUC’s supplies. Testing in 2005 indicated the presence of Chromium-6 as noted on Page 8 of this report.

Source Protection is the primary barrier to water pollution. A contaminant that does not get into the water source does not need to be removed. SFPUC maintains a comprehensive watershed control and management program to protect source water.

The water from Hetch Hetchy Reservoir in Yosemite National Park is so well protected that the Hetch Hetchy water supply is one of only six major water supplies in the country that is exempt from filtration. SFPUC controls activities on the watershed lands around their East Bay reservoirs, limiting activities to those compatible with maximum protection of the water quality.

The quality of the water supplied by local wells is high enough so as to not require further treatment other than disinfection for your protection. The City is committed to providing the highest quality, safe water from its system to our customers.

Water Treatment is the next protective barrier. Water from the remote Hetch Hetchy reservoir and our wells is unfiltered because it meets all state and federal requirements without filtration. Water from the other Bay Area watersheds near populated areas is filtered to meet standards for clarity. All of Daly City’s water is disinfected in order to retain distribution system residuals that meet state and federal quality standards.

Effective Operation & Maintenance of the distribution system assures that the water maintains its quality as it travels through the system to your tap. Minimal chlorine residual is maintained in the distribution system to prevent any regrowth of organisms during storage and transmission of the water as it travels to you. Active flushing of water mains and rotation of stored water supplies also keeps the water fresh and limits growth of organisms.

Daly City conducts continuous water quality monitoring and testing to assure your drinking water is safe and healthy. Daly City, working with the San Mateo County Health Department, maintains an active cross-connection control program to prevent the intrusion of potentially harmful materials into the drinking water system. Cross-connection control is done by isolating hazards (boilers, cooling towers, fire sprinklers, etc.) from the drinking water supply by requiring and overseeing the installation of approved backflow prevention devices, which are annually inspected and certified by trained staff to insure their continued effectiveness.

Capital Improvement Projects

The goal of Daly City’s ongoing Capital Improvement Program is to ensure the quality of your drinking water for years to come.

• Two new interconnections with Brisbane have been added to ensure optimum pressure in the upper zones of the eastern portion of the system. A new interconnection with the SFPUC has been added at MacDonald.

• A new booster pump station is being constructed at Reservoir 8 to add redundancy to the lower end of the east side, ensuring optimum flow and pressure.

• The City has continued to clean reservoirs and clear wells on a schedule of every three years. In 2005, Reservoirs 1, 3, 4 and 8 were cleaned and inspected.

State Certification
All Water Operators possess water treatment certifications issued by the California Department of Health Services. Additionally, all Water Operators and Water Distribution personnel possess water distribution certifications. All water personnel must maintain their certification by completing 16 to 32 hours of educational training during a two-year period. This allows City staff to increase their skill and technical knowledge and to operate the water system in a confident and responsible manner aimed at protecting public health.

Daly City Completes Drinking Water Source Assessment

An assessment of local municipal groundwater production wells of the drinking water source for the City of Daly City was completed in March 2003. The work was performed in accordance with regulations established under California’s Drinking Water Source Assessment and Protection Program administered by the State Department of Health Services (DHS).

Five of Daly City’s six municipal production wells assessed (‘A’ Street, Vale, Jefferson, Junipero Serra and Westlake) were noted as being highly protected from potential pathways of contamination. Well #4 was noted as being moderately protected.

The City’s municipal wells are considered most vulnerable to automotive related activities (gasoline stations, repair facilities), highways, roadways, sewer lines and railroads (BART) that result from the commercial and urbanized character of the overlaying land in the community. While the source assessment results are positive, they underscore the importance of ongoing monitoring and remedial activities now taking place to ensure the water quality of this local resource is preserved for potable purposes.

A copy of the complete assessment is available from the DHS Drinking Water Field Operations Branch, 850 Marina Bay Parkway, Building P, 2nd Floor, Richmond, CA 94804. You may also obtain a summary of the assessment by contacting either DHS District Engineer Eric Lacy at (510) 620-3453, or Daly City’s Director of Water and Wastewater Resources Patrick Sweetland at (650) 991-8200.

Water Quality Data Table

Other Health Related Information

Cryptosporidium & Giardia
Cryptosporidium and Giardia are found in most surface water supplies and can pose a potential health threat. If ingested, either may produce symptoms of diarrhea, stomach cramps, upset stomach, and slight fever. Some people are more vulnerable to Cryptosporidium than others and should seek advice about types of drinking water from their health care providers. The SFPUC tests regularly for Cryptosporidium and Giardia in both source and treated water supplies. Both were occasionally found at very low levels in the SFPUC’s water in 2005.

Drinking water, including bottled water, may reasonably be expected to contain at least minute amounts of some contaminants including Cryptosporidium and Giardia. The presence of small amounts of contaminants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the Environmental Protection Agency’s Safe Drinking Water Hotline at (800) 426-4791.

Please note that Cryptosporidium and Giardia are associated with surface water supplies and are not commonly detected in groundwater. Daly City’s wells in previous years have never had a detected level of either of these microbes.

New regulations for reporting arsenic levels have been established at less than 10 ug/l. Staff has completed preliminary testing of its groundwater at five local wells. Current testing standards detect arsenic at 1 ug/l, and the Junipero Serra Well test results were 1.4 ug/l, while all other wells tested were non-detect. While results are below the standard, Daly City will provide an informational statement if for any reason sampling exceeds 5 ug/l (one-half of the new standard) as this testing program is implemented.

Nitrate in drinking water at levels above 45 mg/L is a health risk for infants of less than six months of age. High nitrate levels in drinking water can interfere with the capacity of an infant’s blood to carry oxygen, resulting in serious illness; symptoms include shortness of breath and blueness of the skin. High nitrate levels may also affect the ability of the blood to carry oxygen in other individuals, such as pregnant women and those with certain specific enzyme deficiencies. Nitrate levels may rise quickly for short periods of time because of rainfall or agricultural activity. If you are caring for an infant, or you are pregnant, you should seek advice from your health care provider.

Chromium is currently regulated under the 50-microgram per liter (ug/l) maximum contaminant level (MCL) for total chromium. There is no MCL established at this time for Chromium-6; however, testing from three Daly City wells were as follows:

Well #4 - 19 ug/l   Jefferson Well - 9.7 ug/l   Vale Well - 16 ug/l

For additional information, please refer to the California Department of Health Services website at: http://www.dhs.ca.gov/ps/ddwem/chemicals/Chromium6/Cr+6index.htm

Energy Star Clothes Washer

Rebate Program ~ Save $50 to $150

The City of Daly City is offering a rebate of $50-$150 to residents who purchase and install an Energy Star clothes washer. Most major appliance brands offer models that qualify for the rebate.

High-efficiency washers with the Energy Star label use 38% less water and 56% less energy than standard-efficiency models. In addition, the super-efficient washers extract more moisture from clothes, thereby reducing the time and energy used for drying. The increased efficiency translates into 13,500 to 36,000 gallons of water saved per machine per year. Tests have shown that Energy Star washers get clothes cleaner, rinse more thoroughly, treat clothes more gently, and use less detergent than other washers.

Additional information, including a list of qualified washers and rebate applications, is available from your local appliance retailer selling Energy Star washers or from Daly City’s Ward Donnelly at (650) 991-8208.

Frequently Asked Questions

1. How Do I Know My Water is Safe?
In order to insure that tap water is safe to drink, the U.S. EPA and the State Department of Health Services (DHS) prescribe regulations, which limit the amount of certain contaminants in water provided by public water systems. DHS regulations also establish limits for contaminants in bottled water that must provide the same protection for public health.

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. 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. EPA/Centers 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 (800-426-4791) or on the U.S. EPA’s website www.epa.gov/safewater/hfacts.html.

2. My drinking water is reddish or brown. What causes this, and what can I do about it?
This type of problem is called corrosion. If the discolored water is coming only when you have the hot water running, your hot water heater may be rusting. If the discoloration occurs when running your cold water, then the drinking water pipes – in the street, leading to your home, or in your home – may be rusting. To clear the water, let the cold water run in your bathtub for 5 to 10 minutes. (Save the rusty water for plants.) If your water does not become clear after doing this, notify the Department of Water and Wastewater Resources at (650) 991-8200.

3. Should I buy bottled water?
Buying bottled water is a matter of personal choice. In the U.S. bottled water is less regulated than municipal drinking water. Bottled water is also hundreds of times more expensive. Five gallons of Daly City tap water costs you about 2 cents. Five gallons of bottled water from the grocery store will cost you, on average, about $5. That’s 250 times more expensive than tap water!

Of course, in emergencies bottled water can be a vital source of drinking water for people without access to clean water. Our country learned vital lessons from Hurricane Katrina, and one of those lessons is that we need to be able to sustain ourselves for up to 7 days following a disaster. In terms of bottled water, famlies are encouraged to store 1 gallon of water per person per day for up to 7 days. And just remember that bottled water has a shelf life, so you should periodically change the water you store for emergencies. And if you regularly use bottled water, consider it a food and refrigerate it after opening.

4. I use a lot of water in the kitchen. How do I conserve there?
Here are several tips:
• Scrape dishes without using water and don't rinse them before putting into the dishwasher.
• Clean vegetables in a pan of water rather than under running tap water, then use that water for your household plants.
• Use the garbage disposal sparingly.
• Run the dishwasher only when it is full.

5. How should I water my lawn to avoid wasting water?
Water your lawn for long periods a couple of times each week, rather than every day. This allows deep penetration of the water. Water your lawn early in the morning to avoid excessive evaporation. Use a sprinkler that makes large drops, because small drops evaporate faster. Try to avoid watering paved areas, and don’t use your hose to wash sidewalks or driveways. Both of these practices waste a lot of water.

If English is Not Your Primary Language
This report contains important information regarding your health and drinking water. Call the Daly City Water and Wastewater Resources Dept. (650-991-8200) should you require assistance in Chinese, Spanish or Tagalog.
Chinese Translation
Este reporte contiene información muy important de su salud y el agua que toma. Llamea Daly City Water and Wastewater Resources Department a (650) 991-8200 si necesita asistencia en Español.
Ang ulat na ito ay naglalaman ng mahalagang impormasyon tungkol sa inyong kalusugan at sa inumin ninyong tubig. Mangyari po lamang na tawagan ang Daly City Water and Wastewater Resources Department sa numero (650-991-8200) kung kinakailangan ninyo ng tulong o interpretasyon sa wikang Tagalog.