Overview of Water Epidemiology Program

The drinking water epidemiology program is the centerpiece of a unique collaboration between the San Francisco Department of Public Health and the Public Utilities Commission. Our aim is to ensure a safe drinking water supply by acting as a resource to the Public Utilities Commission with regard to health issues related to drinking water. We provide immediate support and response to events that raise health implications and concerns. This includes coordinating surveillance in the event of water quality problems, providing fact sheets or press releases in response to public concerns when water quality study results are reported in the media, responding to media and customer inquiries regarding water information related to San Francisco's Public Utilities Commission water quality and providing health perspective on legislative measures concerning  the San Francisco's Public Utilities Commission Water Quality Division.

Projects:

Cryptosporidiosis Surveillance Project

The San Francisco Bay Area Cryptosporidiosis Surveillance Project is coordinated by the San Francisco Department of Public Health in cooperation with the San Francisco Public Utilities Commission, the California Emerging Infections Program, and local health departments. This is an active surveillance program, using phone, email, and fax to obtain reports of confirmed cryptosporidiosis from clinical laboratories serving patients in the counties served by SFPUC: San Francisco, Alameda, San Mateo, Santa Clara, and Tuolumne. There are three main goals of the project:

Enhance reporting of human cases of cryptosporidiosis

Monitor trends over time

Detect increases in the number of reported cases or outbreaks early enough to allow timely investigation and possible intervention.

Free lead-in-water testing for WIC-eligible families

 The Water Epidemiology program coordinates the program to provide free lead-in-water testing for WIC-eligible families in San Francisco. (WIC is a special supplemental nutrition program for women who meet income guidelines and who are pregnant, breastfeeding, or have recently had a baby, infants, and children under five years of age.)

 

The purpose of the free lead-in-water testing program is to is to ensure that lead testing is available to people even if they can not afford to pay the $25 fee normally charged by SFPUC for this service. Although testing for lead in water is a way of ensuring that exposure to lead in drinking water is detected and minimized, there is substantial evidence that drinking water is not a significant route of exposure for lead in San Francisco.

 

WIC-eligible families in San Francisco may participate in this program by:

1.  Visit one of five WIC offices in San Francisco and ask for a voucher for one free lead-in-water test.

2.  Then call toll-free: (877) 737-8297 to arrange for a free lead in water test.

Participants must have their voucher from the WIC office before calling to arrange the test.

Fact Sheets and Public Information

The water epidemiology program develops fact sheets on a number of topics. These may be found by clicking on the water epidemiology publications link.

 

Legionella: Impact of drinking water disinfectant conversion from chlorine to monochloramine

This study was a collaboration with the Centers for Disease Control, the California Emerging Infections Program, the California Department of Public Health, the San Francisco Public Utilities Commission Water Quality Division and the San Francisco Department of Public Health. The study found that switching from chlorine to monochloramine for disinfection dramatically reduced Legionella colonization in buildings that receive municipal water. The complete results of the study are found in the manuscripts Reducing Legionella Colonization of Water Systems with Monochloramine in the Emerging Infectious Diseases journal, and Legionella reduction after conversion to monochloramine for residual disinfection in the Journal of the American Water Works Association. In January 2009, the latter manuscript was selected for the 2008 AWWA Water Quality & Technology Division Best Paper Award.  

Emergency Planning

We collaborate with the San Francisco Public Utilities Commission on developing emergency plans. Some of the plans we have developed include an action plan in the event of detecting viable cryptosporidium oocysts in the drinking water, a plan for response to a flooding event, and a plan for responding to intentional contamination. We provide information about the possible risks posed and the appropriate public health responses that could be implemented in each scenario.

Regulatory support

We provide regulatory support by interpreting relevant medical literature to assist with regulatory compliance issues and by providing comments on proposed new regulations. We have provided regulatory support for the Lead and Copper Rule, the Disinfection Byproducts and the Long Term Enhanced Surface Water Treatment Rules, as well as providing input into the annual Consumer Confidence Report.

Chloramine Conversion Support

The drinking water epidemiology program has been providing information and support to the SFPUC since the conversion to monochloramine for residual disinfection in 2004, to ensure a safe drinking water supply. SFDPH continues to support the use of chloramine for secondary disinfection in the SFPUC water system. Please click for more information on SFDPH work relevant to chloramine.