Animal Waste, Water Quality and Human Health

oundaries of their limitations. Within the context of local, political and publichealth frameworks, remediation schemes may be developed for the reduction ofmicrobial contamination to adjacent surface water. These coordinated efforts arefurther supported by the management of human behaviour, such as citizenengagement and public education campaigns, designed to increase awarenessregarding surface water management.8.3.1 Eradication and control measuresChapter 4 addresses the management of livestock herds at the direct level:controlling inter-animal pathogen transmission, culling of infected cattle, the useof antibiotics, bacteriophage treatment, conservation issues, bio-security andvaccination. Chapter 6 discusses the management of farms, where animal excretaare generated. Farm management measures to prevent or reduce the transportof microorganisms include riparian filter strips, animal exclusion (fencing,providing alternative watering points), waste retention or re-use, management ofanimal wastes (slurry storage or biogas systems), farms ponds and constructedwetland buffering systems. Chapters 5 and 7 describe the fate and transport ofmicro-organisms and emphasize the potential utility of microbial source trackingtechniques as a surveillance and evaluation tool to judge the possible success ofon-site preventative measures by assessing the ambient water environment. InChapter 8 “downstream” preventative or mitigation measures are addressed.These are measures that may be taken to improve water quality and preventthe transmission of disease as a complement to herd management or on-sitemanagement measures or as a substitute where such measures are impractical,socially unacceptable, or where the definitive source remains unidentified.The design of downstream mitigation measures tends to be based on variousmonitoring techniques and may include physical alterations to the environmentbut also encompass managing human behaviours through regulatory oreducational means.8.3.2 Physical alterationsExposure interventions 291Physical alterations to the natural environment that have proven successful inreducing faecal contamination of surface water include: vegetated swales,natural or constructed wetlands, riparian buffer systems, barriers (berms, dams,curtain technologies), exclusion measures (fencing, wiring), and harassmenttechniques. While wetlands, vegetative swales, and riparian buffer systems haveproven useful in improving water quality in agricultural settings (see: Chapter 6)(Gathumbi et al. 2005, Kay et al. 2005), these same measures are also effective