Half the county's residents under a "Boil Water" advisory

[papaof2]

I think County Water needs to address their "replace at 40 years" policy for some of their bigger pipes in other areas of the county. We're currently under a "Boil Water" advisory (second one in two years) because of a broken 36" water main (and I think it's the same main or in the same area as last year's break - I'd have to check the County's "advisory" emails back for a year). The advisory covers the southern third of the county (about half the county's population) and is in effect for at least 24 hours (time to get water test data back from the lab). We're not greatly affected - I can bring a 5 gallon water container or two up from the basement and be good for that time frame. Both Brita pitchers are filled so we have convenient water until I make that trip on the stairs. If needed, we could boil water in the large stock pot (couple gallons at a time) to process the water quickly but I have eight 5 gallon water containers so we should be OK for a day or two ;-)

Or I could set up the Sawyer Point Zero Two filter and run water through it at one faucet (probably at the kitchen sink) so we could have unlimited clean water at the turn of a faucet.

Or if they say a week or more, then bring in the last food grade 55 gallon barrel that's sitting outside waiting to be used for rainwater collection and put it in the basement. Rinse and fill that barrel using the using the Sawyer filter and then add a submersible 12 volt pump with 50 feet of potable water hose to that barrel and bring "running water" to the kitchen sink. That would require some time but I do have all the parts. If I have an "on demand" pump (need to check the "DC pumps" box), the new, temporary faucet near the kitchen sink would work just like "normal" but be providing filtered water when that faucet is turned on. There's also 10lbs of activated carbon if I want to add taste and chemical filtering.

Nah, you don't need to make allowances for stuff breaking - everything works fine, every day, all the time.

I did put 4 quarts of water on to heat because it's easier on my back than bringing an almost 50lb container of water up the stairs. Last time we had a "Boil Water" advisory, they cancelled the advisory before the first pot of water had cooled enough to be used...

[techsar]

Lots of that going on around here as well. Two different water providers are affected.

Fortunately, we aren't on them...having a nice deep (600+ ft) well to draw from keeps us from the issues. And yes, I have enough materials on hand to replumb the system if ever necessary.

[iamnobody]

Jan 19, 2024 11:51:58 GMT -6 papaof2 said:

Nah, you don't need to make allowances for stuff breaking - everything works fine, every day, all the time.

Just like the "just in time" delivery systems that everyone depends on........

[papaof2]

Jan 19, 2024 20:45:39 GMT -6 iamnobody said:

Jan 19, 2024 11:51:58 GMT -6 papaof2 said:

Nah, you don't need to make allowances for stuff breaking - everything works fine, every day, all the time.

Just like the "just in time" delivery systems that everyone depends on........

The only reliable "Just in time" delivery system is our pantry. It's always there. It stays 90% filled. There might not be anything "quick and easy" but cornbread just requires time for the oven or the cast iron skillet to heat - still much faster than driving through the storm looking for that last loaf of bread and gallon of milk at the grocery store or a fast food place that's open. Maybe I've gotten lazy in my old age? ;-)


County Water's email said "24 hours" to get data back from the lab so their ball park for passing that info along is probably after 8AM but before noon today. Meanwhile I've poured up the water boiled yesterday into the two Brita pitchers and a couple of non-spill Contigo mugs plus a cup from Disney's Port Orleans resort that has a thumb-operated lid and it's on the counter in the master bath as a mini-pitcher for water for brushing teeth. And there's another gallon of water on to heat. I'm estimating 20+ minutes for it to be at a good boil and then I'll cover it for use later today, if needed. (Actually, 21 minutes to reach boiling.)

One more "Boil Water" advisory and I think there will be an "Emergency Water" faucet/spigot of some type near the kitchen sink. Just connect a full 5 gallon container to the 12 volt pump and we'd be good for a while. If that became a regular event, putting the Sawyer filter inline to fill that 55 gallon barrel and running that to the kitchen via an "on demand" pump sounds even better.

The best info I can find about the Sawyer Point Zero Two at the moment is 600 liters (158 gal) per day (on the box itself). The Sawyer website says 170 gallons/day. I know I found the maximum pressure and flow documents somewhere but A) that was a long time ago: I bought it from REI for $91 + $5 shipping, B) I'm not finding that reference online and C) my copy might have been lost when a laptop "walked off" a year or so back :-(

I did find links to the pressure & flow documents on the Sawyer site but those links now give a 404 ("Not found") error so they've either taken the pages down or made them internal only. I knew I wasn't crazy about those having been available IN THE PAST. This page: www.jicreadiness.com/assets/images/14%20%20Sawyer-Filter-Technology.pdf
has the no-longer-valid links to that info so it's not just "that crazy old man" who knows the info WAS out there.
The Point Zero Two box has minimal instructions inside - drawings with a little text and a large (8" by 6") adhesive label for the 5 gallon bucket (if you're using a bucket).

Guess I'll be digging out a couple of the ancient backup drives to see if that info got saved there. Be nice if the Point Zero Two filter could handle at least 3GPM so it could feed the house water system. That would include having clean water for showers and washing dishes - dishwashers don't get hot enough to kill micro-organisms unless they have a "hot-Sani" or similar cycle - and you'd have to sort out which plastic or plastic-handled kitchen items couldn't be washed in water that hot :-(

If we need to wash dishes, Clorox has the instructions online in their "Purifying water with bleach" document. Make up a solution of chlorine bleach and water and dip the dishes in it for c=xx seconds and then let them air dry. www.clorox.com/learn/how-to-sanitize-dishes-with-bleach/

Sand filters are often used in commercial/industrial/municipal water systems, usually with additional means of treatment(sometimes including UV light "filters" that the water must pass around to kill micro-organisms). You can build a big a sand filter as you have space and $$$ for so throughput would ne be an issue.
Quick reference on sand filters: www.hwts.info/products-technologies/074f5f20/biosand-filter/technical-information
More info on sand filters here: biosandfilter.org/biosand-filter/filter-media/sand-as-a-filter-media/
There's a manual for using sand filters here: www.biosandfilters.info/ (bad link and a site search sends you another bad link)

[papaof2]

This is info I collected in researching slow sand filters when they were introduced in "Jack's War - Book 1"

55 gallon barrel diameter = 22.5 in
radius = 11.25 in
surface area = 397.61 sq in = 0.2565 sq meter

From www.itacanet.org/doc-archive-eng/water/Intro_SSF.pdf

100-300 l/h per sq m of filter area

55 gallon barrel slow sand filter would be 25.65 to 76.95 l/h or 6.77 to 20.32 gal/h

minimum sand depth of 0.6 m = 1.968 ft
maximum sand depth of 1.7 m = 5.577 ft
start with 1.2 m = 3.94 ft and let it pack down

gravel layer under sand to keep sand from blocking drain pipes
gravel in 4 sizes

gravel bed can be replaced with geotextiles (weed block / ground cloth)

minimum water depth above sand 1 m = 3.28 ft
maximum water depth above sand 1.5 m = 4.92 ft

output should go to a weir high enough to ensure sand bed stays wet if input water supply stops - or just bring water up from bottom of tank with pipe and fittings so spigot is above sand in barrel.

should be followed by a filter of crushed activated carbon (5 gallon bucket full - about 25lb)

sand and gravel should be washed to remove dust/dirt

activated carbon should be rinsed to remove dust
may need cloth or paper filter to catch carbon dust for some time after building filter

[gipsy]

Cool info

[papaof2]

One further note:

Based on the estimated amount of activated carbon in a Brita filter, 10 lbs of activated carbon should be good for treating at least 4000 gallons of water for taste, chemical, etc. I previously posted a chart of how well activated carbon adsorbs various chemicals in one of the forums. Figuring that out took some serious math to get from the grams of activated carbon in the Brita filter and then dig up how many gallons turn on the red "change filter" light in the newer pitchers and make some correlations among grams and gallons. My math is probably good within +/- 50% but you have a ballpark value ;-)
Someone with access to laboratory grade equipment can probably make a more accurate determination.

[papaof2]

You might find a bit of the history of the slow sand filter interesting: en.wikipedia.org/wiki/Slow_sand_filter

Or how the "muck" layer works to collect the micro-organisms: www.mdpi.com/2073-4441/14/7/1078

The Sawyer Point Zero Two filter has similar micro-organism filtering to the best of the slow sand filters - possibly what your local water supplier uses - but in a package you can hold in one hand. But the Sawyer is only designed for up to 170 gallons/day. If you let everyone have 10 gallons a day for a sun shower and 2 gallons a day for drinking, cooking, etc, the Point Zero Two would support 170 / 12 = 14 people if the water source was capable of that much daily flow. Make that two 10 gallon sun showers a week and it would support (7 * 2) + (2 * 10) = 34 gallons/person/week but the Point Zero Two does 7 * 170 = 1190 gal/week. 1190 / 34 = 35 people. Sawyer suggests back flushing after 1000 or so gallons to retain maximum capacity. Back flushing the filter needs 150 ml or or about 5 oz or less than 1 cup of clean water. Sounds like a great piece of equipment ;-)

The filter elements in the Point Zero Two are enhanced versions of the filters used in kidney dialysis machines. just beefed up to take higher pressures and greater flows and with the pores shrunk down so they don't pass viruses. Typical viruses are 25 nanometers. The Point Zero Two's 2 microns is 20 nanometers so the Sawyer filters too finely to be used in a dialysis machine. Sawyer no longer sells the Point Zero Two in the US so I was lucky to have seen the specs on the filter and buy while they were still available in the US (in 2016).

If I had a water source big enough, I could provide limited water for the neighbors. The absolute minimum water is 1 gallon/day for an adult but I consider 2 gallons a day more realistic where we are. 170 gal/day divided by 2 = daily water for 85 people - but I suspect there would be someone (or more than one "someone") who wanted unlimited water. If we were in a long-term "no water" event, I should ask "How many of you have a tank style hot water heater?" and make them contribute for everyone else's benefit. I'd probably have to shoot whoever tried to take the filter from me (maybe multiple "whoever") - but that would reduce the total amount of water (and food) required daily. After an SHTF or a near-SHTF event, we will be in a harsh world...

An "Exam Prep" page for a class on slow sand filters which has a lot of useful info packed into a small space: water.mecc.edu/exam_prep/slowsand.htm

Another university page: www.ce.memphis.edu/1101/notes/filtration/filtration-1.html