SAN DIEGO (FOX 5/KUSI) -- San Diego County Public Health Services staff and volunteers are walking door-to-door in South County neighborhoods Thursday. They are handing out handing out information about an upcoming community health assessment, led by the Centers for Disease Control and Prevention, to address sewage pollution along the Tijuana River Valley. “We know that many community members are worried about their health and the health of their families because of the sewage contamination in their beach water and the Tijuana River Valley,” said Dr. Ankita Kadakia, interim public health officer. “We are pleased to have the support of the CDC partnering with the county so that we can listen to those concerns and experiences and get a big picture snapshot of the needs in these areas.” More than 6,000 households will receive information on flyers and doorhangers about the survey known. It's known as a Community Assessment for Public Health Emergency Response, or CASPER.   More information can be found on the county's website.