Water treatment

[Spyder1]

Did I miss something noticed on park website today they are saying filtration AND chemical treatment for drinking water? We have been using a platypus for years 2 micron filtration thought that was sufficient. Just don’t remember both being recommended. Thoughts?

[Midwest Ed]

Initially I was going to say you were mistaken, but after reviewing the website again I see they are now indicating chemical treatment is needed in ADDITION to either boiling or filtering. Recommended filter size is 0.4 micron not 2. I think it's always been 0.4. I will not contradict the park services statements but I don't remember the need for chemical treatment last season. It certainly was not in earlier years past. Iodine tablets are of course of no consequence from a weight standpoint but they will add some time to water preparation.

I am curious as to their reasoning. Has there been new testing, recent infections traced to the water, or just an abundance of caution (given the present pandemic)? I just looked up the size of SARS Covid 2 and the average size was said to be 0.12 microns and that is considered large for most viruses (some other virus are as small as 0.02 microns). I think there are filtration systems said to be suitable for viruses but I do not know how portable they are now days (the ones I saw were not suitable for backpacking).

Note: Chemical (or UV light) treatment alone will NOT rid the water of the tapeworm parasite that can be present. Also, if an algae bloom is present then no amount of any treatment is effective. These lakes are closed to human use when this rarely occurs.

[Spyder1]

That’s what I thought it’s actually .02 microns so I think I will stick with the platypus only it’s seems to have been sufficient for all these years although they say the cysts can take years to develop which is a little scary. But then again what isn’t scary these days!

[Ingo]

I haven't heard of any new concerns about the water on the island, so I would think it's an abundance of caution. I think it (chemical treatment) was added maybe last year? I've never treated, just filtered.

[Midwest Ed]

The Platypus filter is 0.2 microns which is 10 times larger than the smallest virus and also almost twice the size of SARS Covid 19. Ingesting some viruses like Hepatitis or Norovirus can certainly cause infections (I always rinse the top of canned food before opening as rodents could be running around warehouses). From what I've read there is so far no evidence the SARS/Corona family is transmissible via ingestion, but primarily through respiration. Hard to believe there's SARS on Isle Royale (yet). Plus it's my pure speculation it's even playing a part in the Park's thinking. I did check the 2020 Greenstone and there's no mention of chemical treatment requirements so it is new.

I have always personally thought that any water (especially non-flowing) near or downstream from human activity (especially sewage) deserved chemical treatment. It's difficult to fathom that situation would ever be encountered on the Island. I've sometimes wondered about filtering water from a puddle up on a ridge or from a stagnant beaver pond. Still, I'm not suggesting to anyone to go against present Park standards. I tend to agree it's choice #3 (caution) but it would be good to know more about management's decision process. I hesitate to even bring it up but what's next, recommendations to sanitize shelters and picnic tables before using?

[johnhens]

From the NPS Health page: It seems the NPS is advocating treating all water as if it has viruses. Use what ever treatment method makes you comfortable. I have never treated for and never worried about viruses in the backcountry in the US.

Your backcountry outing may take you far away from running water. When planning your trip, you should pay attention to where you will be able to access clean drinking water (whether from a potable water tap or natural source). Remember: Water from natural sources must be purified by boiling or filtering and disinfecting.

Always store potable water in clean containers. When possible, use water from approved park facilities. If you will be drinking water collected from a natural source, you need to treat it first to remove bacteria, viruses, and other organisms that can make you sick. Water collected from natural sources can be cleaned in two ways: (1) boiling, or (2) filtering and disinfecting. Filtering does not remove viruses, which is why disinfecting is needed as well. Instructions for both methods are listed below:

Boiling Filter and Disinfect
If water is cloudy, allow it to settle.

Bring clear water to a rolling boil for 1 minute or 3 minutes if elevation is over 6,500 ft (2,000 m).

Filter water through a 1 micron filter.
Disinfect with bleach according to the table below
Let water sit for at least 30 minutes before drinking.

Use the table below to determine how much bleach to add, depending on concentration of sodium hypochlorite:

Volume of Water Amount of 6% Bleach to Add Amount of 8.25% Bleach to Add
1 quart (liter) 2 drops 2 drops
1 gallon 8 drops 6 drops
2 gallons 16 drops (1/4 teaspoon) 12 drops (1/8 teaspoon)
4 gallons 1/3 teaspoon 1/4 teaspoon
8 gallons 2/3 teaspoon 1/2 teaspoon

For more information, visit the CDC Backcountry Drinking Water Guide. https://www.cdc.gov/healthywater/pdf/dr ... atment.pdf

[Kelly]

Somewhere along the way, I have read conflicting information on filtering and/or treating water on ISRO. To be on the safe side, at some point I started using Betadine in addition to filtering.

[TopCarrot]

The ranger we asked said it was for the NoroVirus on the inland lakes and was erring on overly cautious.

[Midwest Ed]

Norovirus. Interesting. Norovirus is spread through ingestion of contaminated food or water and manifests in an almost always non-lethal (except for the very compromised) case of gastroenteritis (stomach bug or stomach flu-tho not the flu) lasting 1 to 4 days. You can remain infectious for months. It's physical size is as small as 0.020 microns. This 5 to 40 times smaller than the popular backpacking filters so indeed a secondary treatment method is needed (boiling or chemical). Note: Proper boiling negates need for filtering (except for taste improvements).

So, this leads to the question, why norovirus and why now? Was testing done on or near the Island or were surveys done in other national park areas resulting in a national memorandum. Assuming all of this is true as I'm still not a MD or epidemiologist. My personal outlook on filtering only anywhere near human activity was just reviewed.

[torpified]

So, this leads to the question, why norovirus and why now? Was testing done on or near the Island or were surveys done in other national park areas resulting in a national memorandum. Assuming all of this is true as I'm still not a MD or epidemiologist. My personal outlook on filtering only anywhere near human activity was just reviewed.

Nothing national, I don't think. I've gone on modest trips in two National Parks in California (Yosemite and Sequoia/Kings Canyon) in the past month, and neither wilderness briefing included more stringent guidelines for water treatment than the previous normal.

[Base654]

I picked up a sawyer purifer a couple years ago for travel outside the country. It's different than the filter. So far I have been able to drink the "do not drink the water" water without adverse effect. It claims to purify to 0.02 microns. It costs about $140, looks about the same as their big filter but is about the size of my fist.

[Bobcat1]

In 2018 (?) late in the season (right around Labor Day) there was a norovirus outbreak on the east end of Isle Royale. A number of people got sick. In 2019, one of the seasonal rangers was telling about having been evacuated from the island two weeks early because she was one of the people who got sick "in the outbreak". So maybe there is heightened concern about noroviruses in particular.

[jerry]

Interesting, the rangers only worried that this old man had trouble hiking on the east end last year. They all seemed to know about me. Never heard about norovirus from them.