Racine
Beach Grooming Tactics to Reduce Swimming Bans
Project Description
Racine, Wisconsin lies on the southwestern shore of Lake Michigan,
approximately 80 miles north of Chicago, Illinois and 30 miles south
of Milwaukee, Wisconsin. The city has two public bathing beaches stretching
over a mile of shoreline that provide an opportunity for the citizens
of Racine to enjoy a variety of recreational activities at the lakefront.

As a best management practice, the City of Racine, Wisconsin, altered
beach-grooming techniques as a means of reducing diffuse (non-point)
pollution to Lake Michigan. A 2-year research initiative demonstrated
that past practices acted to increase bacterial indicator density in
beach sands. Adjustments to the current equipment employed in beach
maintenance provided a no cost means of reducing the frequency of dry
weather advisories in this community.
Project Background
Elevated levels of the current recreational water quality indicator
organism (E. coli) in bathing waters at North Beach, a popular recreational
site in Racine have been a persistent problem often resulting in advisories
or closures. Evidence does not exist for any significant sewage contamination,
nor is there a consistent association between high bacterial levels
and rainfall. It is believed that increased E. coli counts are likely
due to non-point source (diffuse) contamination. High populations of
seagulls in nearshore and offshore areas are common and may serve as
sources for contamination. Previous research performed in Racine showed
a statistical relationship between E. coli densities in bathing waters
and wave height. Because of this relationship a plausible transport
mechanism was identified, namely, high waves irrespective of rainfall,
could serve to transport bacteria from beach sands to surface water.
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In Racine, the current beach management practice
involves daily grooming of the beach sands for the removal of
debris and to create an aesthetically pleasing environment for
beach patrons.
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Barber Surf Rake Mechanical Beach
Groomer towed behind a tractor.
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The Wisconsin Department of Natural Resources (WI DNR) funded an initial
study in 2001 in order to determine if this practice was responsible
for the high density of E. coli recovered from beach sands. Aided by
Dr. Richard Whitman (USGS), we examined four treatments, varying the
depth and frequency of beach sand grooming (including the current practice).

It was found that deeper grooming without leveling of the beach sand
significantly reduced bacterial density. The Root-Pike Watershed Initiative
Network (WIN) funded a follow-up study in 2002 in order to determine
if this same reduction in bacterial density could be achieved beach-wide
through altering the settings on the current mechanical beach grooming
equipment (Barber Surf Rake Mechanical Beach Groomer, Model 600
HD, Naugatuck, CT).
Project Results
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Before:
Past grooming practices leveled and compacted beach sands increasing
bacterial density.
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After:
Current grooming practices remove debris from beach sands while
reducing bacterial density.
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The 2002 WIN funded study produced data paralleling the initial study
performed in 2001. Namely, deep grooming without leveling served to
reduce the density of E. coli recovered from beach sands. In light of
this information the City of Racine Parks and Recreation Department
began altering their beach grooming practices effective May 2003. This
change has resulted in a 30% reduction in the number of dry weather
advisories/closures posted this year (25%) as compared with 2002 (55%).
Project Contact
Julie Kinzelman, Microbiologist
City of Racine Health Department Laboratory
730 Washington Avenue
Racine, WI 53403
(262) 636-9501 phone
(262) 636-9576 fax
jkinzelman@cityofracine.org
Document prepared October 17, 2003