TITLE:
Attachment of Escherichia coli to fine sediment particles within construction sediment basins
AUTHORS:
Elizabeth A. Kunkel, Charles V. Privette, Calvin B. Sawyer, John C. Hayes
KEYWORDS:
E. coli; Sediment; Sediment Basins; Erosion; Stormwater; Runoff; Construction
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.4 No.3A,
March
29,
2013
ABSTRACT: The conventional best
management practice of sediment basins may create a reservoir for pathogenic
bacteria. The fine particles that enter these basins have been shown to provide
protection for bacteria; the small pores of clays and silts minimize predators
and block sunlight. Therefore, while these basins decrease sediment loadings
to water bodies downstream, they may introduce harmful levels of pathogenic bacteria into surface waters. In addition to causing human health risks, high
bacteria levels alter natural biological makeup of downstream ecosystems. This
paper describes the attachment of Escherichia
coli to various particle sizes in construction site sediment basins. Five
sediment basins, located in Anderson, South Carolina were sampled after rain
events to explore trends that exist between various particle sizes and E. coli densities. Results provide
evidence to suggest that sediment basins are a reservoir for pathogenic
bacteria. Data showed that most E. coli attached to smaller particles with
diameters less than 0.004 mm. These particles do not settle out of the water
column quickly and are often passed through the basin during intense storms. Consequently,
high levels of bacteria are passed to downstream waters. This
research provides considerable evidence that the clays and silts within
man-made construction basins can cause detrimental effects to South Carolina surface waters. With this knowledge, better stormwater management practices may be
developed with the goal of remediating impaired surface waters of South
Carolina.