Fecal indicator bacteria are abundant in wet sand at freshwater beaches

Water Res. 2003 Sep;37(16):3978-82. doi: 10.1016/S0043-1354(03)00301-4.


Potential fecal contamination of sand in the wave-washed zone of public bathing beaches is overlooked in beach monitoring programs. Activity in this zone can bring pathogens to the sand surface or into the water, presenting a health risk to sensitive populations. On a unit weight basis (colony forming units per 100g), the mean summer abundance of the fecal indicator bacteria enterococci and Escherichia coli was 3-38 times higher in the top 20 cm of wet-sand cores than in the water column at six freshwater bathing beaches. E. coli were 4 times more abundant than enterococci in water but counts were similar in the sand. A correlation (r=0.60) existed between E. coli counts in the water and in the top 5 cm of sand only, whereas no relationship existed between enterococci abundance in water and sand. In general, enterococci were most numerous in the 5-10 cm sand stratum and E. coli in the 0-5 cm stratum. These preliminary data show that wet freshwater beach sand is a reservoir of fecal indicator bacteria. Enteric pathogens may also be present in beach sand.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Enterococcus / isolation & purification*
  • Environmental Monitoring / methods*
  • Escherichia coli / isolation & purification*
  • Feces / microbiology*
  • Fresh Water
  • Humans
  • Population Dynamics
  • Public Health
  • Recreation
  • Silicon Dioxide*


  • Silicon Dioxide