
E.coli at worst-ever levels in Lake Ontario: advocacy group - JabavuAdams
http://www.citynews.ca/2017/05/05/e-coli-worst-ever-levels-lake-ontario-advocacy-group/
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splitdisk
"Tully said it’s mostly because of the heavy rain, which carries sewage into
Lake Ontario and into creeks and rivers."

Yes, this is the problem. Anyone in the GTA can tell you about the wonders of
our Combined Sewer systems:

[https://en.wikipedia.org/wiki/Combined_sewer](https://en.wikipedia.org/wiki/Combined_sewer)

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Gravityloss
This is like seeing some potentially horrific error handling logic in critical
infrastructure. Wait, it is actually that.

The storm drain should have the overflow-to-river mechanism _before_ it's
combined with sewage?

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platz
I attended a few meetings in which the city of chicago is attempting to
predict the E.coli levels in the water for the next day using data science
techniques.

It was a frustrating experience since the current day's E.coli level
measurement can vary wildly depending on various factors such as time of day,
water depth at site of measurement, month in year, weather, etc...

or maybe sometimes it's just a bunch of birds that all pooped in the same area
on a given day.

Plus, each beach has it's own pattern and correlations; some folks started
adding rules

the USGS has some method of averaging readings, but I was very tempted to try
to find the ideal model that could handle the non-iid beach data. someone on
the net suggested multilevel hierarchical modelling, which i don'f fully
understand.

i think part of the issue is that data is already semi-structured, as well as
time based. one approach is to flatten the structure (assume iid) and make the
data stationary (remove the time component).

but i wonder if something like an RNN would handle the multiple time steps
better.

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cing
Should be "E.coli at worst-ever levels in Toronto Harbour and Lakeshore". It's
an issue, but the entire lake is not teeming with unsafe amounts of E.Coli. In
the summer, there are updating signs about water quality on every beach.

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DeBraid
> entire lake is not teeming w/ ...

Just the parts where the most people live and want to swim. Sad state of
affairs when the land we value most [both fundamentally (water is life) and
culturally (waterfront land most expensive)] is toxic to humans.

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scosman
Toronto beaches are usually very safe (the are measured by the city in the
summer). This is a one-off event caused by a huge storm.

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3pt14159
I swim in Lake Ontario pretty regularly. Think I went until late November this
year. They'll generally put up advisories at the beaches when there is an
uptick, so if you're in the GTA / Niagara region don't keep this from letting
you get out there.

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astrodust
The Toronto Islands are a good example. Swimming on the harbour side is
probably a super bad idea. Swimming on the lake side is probably fine.

It's like a few hundred feet in some cases and a world of difference.

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3pt14159
Yeah I generally swim at Hanlan's Point. The beach is pretty nice and if
you're ok with some butts the lack of children or large crowds is kinda nice.
Though during pride its pretty packed.

