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Naomi, The http://216.235.203.127/NETCOMMUNITY/Document.Doc?id=255 Lyman Lyman C.
Welch From:
owner-beachnet@great-lakes.net [mailto:owner-beachnet@great-lakes.net] On Behalf Of Kasman, Naomi Hi
everyone, My
health unit is in the process of updating our field data entry forms in order
to help with developing predictive models for our beaches. The resources
available are limited, so we're trying to do everything as simply as possible.
I'm hoping to get some suggestions from others about how to measure the
following variables that we're unsure about. 1. Rainfall over past 48 hours - the
question we're having here is whether to use the average rainfall (mm/hour) for
the previous 2 days or whether we should be looking at peaks. For
example, while a 5 minute torrential downpour may not greatly impact the 48
hour average, does it have enough of an impact on bacterial counts that it
should be considered separately? 2. Current rainfall - what methods do
people use for determining whether current rainfall (i.e. at the time of
sampling) is 'low', 'medium', or 'heavy'? 3. Bather density - we have always had a measure for
bather density included on our field reports, however as our samples are taken
quite early in the morning, there are not usually many people on the beach and
it is certainly not representative of the bather density at peak times. Have
other areas encountered this problem and, if so, how was it dealt with? Have
people found that bather density is of sufficient importance to bacterial
counts that it needs to be measured? 4. Wave height - what methods are people using for
measuring wave height, and how are they defining a wave (is it from the level
of the calm water to the top of the wave, or from the bottom of the wave (which
may be lower than the calm water level) to the top? Also, does anyone have a
coding system for what would be considered 'low', 'medium', or 'high'
waves? Thanks
in advance for all your help! Naomi
Kasman, MSc. The
Tel:
905-830-4444 x4592
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