Reducing microbial contamination in storm runoff from high use areas on California coastal dairies

D. J. Lewis, Edward R Atwill, M. S. Lennox, M. D G Pereira, Woutrina A Smith, Patricia A Conrad, K. W. Tate

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


High use areas are a fundamental part of California coastal dairies and grazing livestock ranches as feeding areas, nurseries, and sick pens. High stocking densities and daily use in these areas lead to soil surfaces devoid of vegetation and covered in manure, with high potential for manure transport during winter rains to receiving waters regulated for shellfish harvesting and recreation. We characterized the association between California's Mediterranean climate and a series of existing and proposed management practices on fecal coliform bacteria (FCB) transport from high use areas on dairies and ranches. Results from 351 storm runoff samples collected below 35 high-use areas indicate that removal of cattle during winter, locating high use areas on level ground, application of straw and seeding, and vegetative buffer strip implementation were significantly associated with FCB concentration and load reductions. These results complement our findings for reductions of specific pathogens in runoff from these areas. These findings have practical significance because they document surface water quality benefits that the studied management practices provide in application on working farms and ranches. This direction is critical and timely for on-farm management efforts seeking to reduce microbial pollution in runoff and comply with indicator bacteria water quality criteria.

Original languageEnglish (US)
Pages (from-to)1731-1743
Number of pages13
JournalWater Science and Technology
Issue number7
StatePublished - 2009


  • Animal feeding operation
  • Conservation practice effectiveness
  • Critical area planting
  • Fecal coliform bacteria
  • Vegetative buffer strip

ASJC Scopus subject areas

  • Environmental Engineering
  • Water Science and Technology


Dive into the research topics of 'Reducing microbial contamination in storm runoff from high use areas on California coastal dairies'. Together they form a unique fingerprint.

Cite this