Effectiveness of constructed farm wetlands in attenuating faecal indicator fluxes to watercourses from yard runoff on livestock farms

Constructed farms wetlands (CFWs) are increasingly being used to treat faecally contaminated ‘dirty waters’ from yard areas on livestock farms. The findings of the present study, undertaken at Pwllpeiran experimental CFW, West Wales, provide empirical data effectiveness CFWs in attenuating faecal indicator organism (FIO) concentrations and fluxes receiving waters which they discharge; insight into extent attenuation rates affected by retention times within CFW seasonal factors. Based maximum flows that a is designed treat, an equation developed enable estimates be made size wetland required achieve desired level FIO attenuation. Other aspects design optimise considered, including construction frequent baffles (transverse ridges), leaving parts cells unvegetated incorporating initial settling pond.