A little background- I have a degree in Civil/Environmental Engineering with an emphasis in water/wastewater treatment.  While I got tired of it and dropped out before I finished, my graduate work was also dealing with water systems and contaminate transport (through urban systems).  I also worked in the industry as a treatment design consultant and/or researcher for several years.  I'm also a backpacker, hunter, camper, prepardness nut and family-man, so my preference in water treatment types, technology and methods is flavored by this mindset.

Here is the text of a handout I wrote for my church group when we did a preparedness seminar.  The Word document of this text contains much better formatting, a table of advantages and disadvantages for various treatments and information on a personal/family sand filter that can be used in the event scarcity of any other treatment components.  If anyone is interested in the Word document please send me (Shane Watson)an email at shane(DOT)watson(AT)ecislc(dot)com.

1-Common drinking water contaminates and treatment
 a.Bacteria
 b.Algae & Dirt/Clay Particulates
 c.Viruses
 d.Cysts
 e.Chemicals
 f.Taste/odors



2-Likely survival-situation contaminates

3-Types of Treatment
 a.Filtration
   i.Reverse Osmosis
   ii.Sand (slow and rapid)
   iii.‘Backpacker’ style filters
   iv.Charcoal
 b.Disinfection
   i.Iodine
   ii.Chlorine
   iii.Commercial Tablets/Drops
   iv.MIOX/ MIOX Pen (MSR)
   v.UV/SteriPen
   vi.Boiling
   vii.Distillation
   viii.Nuclear

4-Wash-water  aka Graywater

5-Wastewater  aka Blackwater
 a.Contaminates
 b.Health Risks
 c.Treatment
 d.Solid Waste (Trash)

6-Water Storage
 a.How much?
 b.Storage Treatment
 c.Where & How


1-Common Drinking Water Contaminates
Contaminates in drinking water are as varied as the places that water is collected from.  Typically municipal systems focus on treating bacteria, algae & dirt/clay, viruses, particulates, taste and odors and chemicals.
-
Bacteria- Present in all water sources, typically groundwater bacteria is not a health risk to humans or animals, although it may have taste/odor issues and minerals that hamper plant growth.  Bacteria is on the smaller end of the spectrum, but will not typically be found unattached to other objects.  It is typically easy to filter the clay and algae particles that the bacteria attach to, but if the filtration process is too violent/abrupt (such as trying to force more water through a filter than it is rated for), it can dislodge the bacteria from its host.

-Algae & Dirt/Clay- Algae & dirt/clay are also present in some form in nearly every water source, including underground.  Most are not harmful but can contribute to turbidity (cloudiness), taste and odor issues and harbor harmful hitchhikers.  Algae particles are typically quite large and very easy to filter, although settling is difficult without an added coagulant such as Alum.  Clay particulates can be particularly difficult to settle and will clog many filters.  The only practical solution is to use the cleanest water possible or give it substantial time in a quiescent basin to settle.

-Viruses – Viruses that are harmful to humans are somewhat rare in most natural water sources in the mountain west.  Typically harmful viruses originate from humans, where there is a any amount of untreated wastewater contaminating the drinking water viruses can be found.  Viruses are very small by comparison and cannot be filtered effectively, but are typically quite easy to kill with common and simple disinfection processes.

-Cysts – Most notably Giardia and Cryptosporidium, these hard-shelled organisms are responsible for many cases of sickness and death- even in the USA!  The hard shell is very difficult to permeate with nearly all disinfection types in typical dosages and contact-times, or the time allowed for the chemical to contact the water before use.  Cysts are very large in comparison to all other organisms and are very easy to filter with the cheapest and most common filter types.  Distillation and MIOX are effective disinfection techniques, but most other techniques can be used in emergency.  Cysts are very resistant to chlorine and iodine-based disinfection and can live outside the host for extended periods of time.  Because of the ease of filtration and relative common appearance of these cysts in water sources, it is best to filter before disinfection.  Giardia related sickness historically was called ‘Beaver Fever’ as it is passed by beaver and many types of livestock  and is very common in streams throughout the mountain west.  Crypto is a relatively new species that is responsible for killing hundreds of people in Milwaukee in 1993, and hospitalizing several thousand more.  It is primarily found in humans with HIV but can be quickly and easily passed to the general public.  

-Chemicals – Inorganic chemicals are not typically treated in normal municipal water treatment, they are found in low enough concentrations that they do not pose a health risk and are monitored, but not treated for the most part.  The only effective treatments for chemical contaminates are distillation and Reverse Osmosis filtration.  These are both costly in both operational and start-up costs.

-Taste/Odors – These are typically very difficult to quantify, identify or locate their origin because of their subjective nature.  They are common in most water sources, especially surface water in the spring and fall months when the water in reservoirs becomes active with temperature changes, but can exist in underground sources as well.  They are easily treated with charcoal filters on both the small and large scale.

2- Likely survival-situation contaminates –
An important consideration in this situation is the increased dosage requirements of all disinfection due to the likely increased concentration of harmful biology in the water supply.  This is a very subjective consideration that will have to be considered on a case-by-case situation when looking for water supply.

a.Viruses- Common in areas where wastewater or human waste is not being transported or treated correctly.

b.Bacteria- Increased concentrations and sources of contamination.  

c.Chemicals-  Likely to be released in urban areas, they may be very difficult to discover.




3-Treatment

a.Filtration-  Filtration is the act of removing particles in the water by passing them through a porous membrane.  Only true Reverse Osmosis will completely treat water through filtration, all other filters will leave some amount of constituents in the water after filtration.  

i.Reverse Osmosis – TRUE reverse osmosis separates water molecules from any other constituent in the water through a filter membrane slightly larger than the water molecule itself.  True RO systems also require a waste outlet and will waste 20-50% of the inflowing water, depending on the characteristics of the water.  True RO will also require a substantial constant pressure (50-150 psi) for optimal operation.  Many filter systems available through Home Depot and similar stores sell products as an RO system, but in fact are little more than a backpacking style filter used under the sink.  RO systems are the only method besides distillation that will remove chemical contamination.  Like distillation, continuous consumption of RO water can result in a mineral deficiency.  

ii.Sand Filters – Sand filters are the primary filtration used in municipal water treatment the world over.  There are two main types, slow and rapid sand filters, both of which can be constructed of relatively common materials, however the operational issues of rapid sand filters make them suitable for municipal settings, where the slow filters can be managed by more simple means.  Slow sand filters depend on a layer of growing biology on top of a thick layer (2-5 ft) of sand to treat both the biological contaminates and mechanically trap constituents in the water.  They require constant water of relatively even temperature covering the biologic layer, as well as several months of operation before the layer is sufficiently treating water for consumption.  Because of the low technology, simple materials and easy operation, slow sand filters are very common in areas where clean water is required with minimal infrastructure.  Two filters should be built at the same time so that one can be taken off-line for cleaning or maintenance and still provide clean water.  After cleaning several weeks to months should pass before the filter is producing adequate water quality again.

iii.Backpacking Filters – There is a large variety of filters on the market for hikers, with effectiveness ranging from excellent to very poor.  Here are a few things to look for in a good filter-
  1.Ceramic/porcelain filter element (NOT fabric!!)
  2..2 Micron average pore size
  3.Sturdy Construction- Good filter will require high pressure and a lot of physical force on the pump.  Some cheaper filters are not well built of designed for the task.
  4.Pre-filter (typically foam)
  5.Filter vs. Purifier vs. ??????- Don’t get sucked into marketing, there is not scientific difference between a ‘Filter’ and a ‘Purifier’.  No matter how good the filter it cannot remove chemicals and all viruses, nor can it magically treat the water to ensure it is 100% safe in all cases.  Stick to average pore size, element type and use a reputable brand, but realize the abilities of what you are buying.

iv.Charcoal Filters – These are common in filters from Home Depot type stores for residential use.  They are very effective at removing taste and odor issues, but can actually grow a substantial amount of biology in the filter without the user being aware as they continue to treat taste and odors.  Because they continue to successfully treat water long after they are actually introducing bacteria into the water, they should be regularly cleaned/replaced.   Carbon is a good method of removing many types of chemicals because of its porous nature, but will quickly become loaded and require replacement.  Again, this loading is difficult to detect as the taste will continue to be improved.  Charcoal can be made of nearly any organic matter, but activated charcoal for filtration is typically made from coconut husk because of its large surface area.  It is also ‘activated’ by immersing it into an acid bath to open the pore structure and make it more attractive to chemicals.  Low-tech methods of creating and using charcoal for filtration and attempting to activate charcoal have limited testing for effectiveness.  Because of the variety of materials used for both the coal and the acid, in addition to the variety in initial water quality, home-made charcoal for filters may remain more of an individual success or failure.  As a precaution, the charcoal from a home-made filter should be changed quite often.

b.Disinfection – Disinfection is the process of killing any biological constituents in the water.  This can be done with or without filtration, but is best when done after at least some filtration.  Many types of disinfection make water safer, but less appealing for drinking because it simply adds more chemicals and tastes to the water.  It is possible to completely treat water from a corral and make it safe to drink, but you will still have a hard time finding a taker without significant filtration.  

i.Iodine – Iodine is a very effective disinfectant for most biological contaminates, but requires extremely long dwell times and high dosage to treat cysts and unfiltered water.  It is relatively cheap and available, but the residual taste, color and odors may require a cover in the form of Kool-Aid or similar to get kids to stay properly hydrated.  Cold water requires a longer dwell time.

ii.Chlorine – Chlorine is a very effective oxidizer for simple organisms, but also requires high dosages for cysts and will result in poor taste issues.  Chlorine is the best way to treat water for storage because of its ability to control algae and bacteria.  Typically a proper storage dosage is undetectable as a taste or odor.  Residual chorine levels are monitored in municipal drinking water systems in order to control algae and bacteria in piping and storage systems.  Hydrogen Peroxide is a viable alternative to chlorine/bleach, but should be purchased in stronger solution strengths than typically available at the corner store.  Peroxide is also much more volatile than bleach and will quickly dissipate if left open to the atmosphere.  As an advantage it can reduce the taste and odor issue common with chlorine/bleach.

iii.Commercial Tablets & Drops – These relatively new tablets are available at hiking and outdoor stores.  They can be dropped into water like iodine, but have an improved success rate against cysts.  They still require long dwell times especially in cold water, and are expensive per gallon of treated water.  The drops consist of two chemicals which are combined to produce a form of Chlorine gas, a very effective disinfection for most constituents.  These must be used as quickly as possible after mixing, and even open, unmixed containers should be used as soon as possible.  Unopened storage life should be very good.

iv.MIOX – MIOX is an acronym for Mixed Oxidants, it is an oxidizing solution created by passing an electrical current through a solution of salt water.  This is becoming the most common method of municipal/industrial disinfection on large and small scale treatment.  Without question this is the best solution for mixed and unknown biology in a water source, and is the most robust in terms of operation, storage and disinfection ability.  Small-scale municipal systems are not tremendously cost prohibitive, and only require 110 V power and a supply of salt.  Small hand-held units are manufactured and sold by MSR for personal/camping applications, and are in use by the US military around the world.  For small scale short term needs this is the best option on the market today, at around $130 each.  

v.UV Treatment – Although UV treatment was very popular for a period of time, it quickly lost favor in the municipal settings and is rife with problems.  UV has the ability to deactivate all biological activity in a stream of water, but because it depends on the water moving past the light source, there is no dwell time, or pools of water being treated.  In the event of failure, the flowing water is not treated and immediately contaminates the stored water downstream.  In applied disinfectants, such as chlorine, the untreated water is mixed with treated water and a residual chlorine dosage which will disinfect the untreated water in the storage basin.  Also, UV light is extremely dependant on producing exactly the right wavelength of light- which is dependent on the temperature of the bulb.  If the water quickly changes temperature the bulb temp can be affected and reduce effectiveness.  The greatest concern, however, is algae in the water and the production of algae on and near the bulb.  If the water is not well filtered dirt and soil particles create UV ‘shadows’ which can protect contaminates from the UV light as bacteria or viruses contained in algae pass through the UV light.  The algae also can collect and grow on the bulb or housing, eventually darkening the light and burning to the housing.  Many millions of dollars worth of practically new UV technology have been removed from systems because of continuous issues with UV.  All of these problems exist on the small scale as well in products such as the Steri-Pen which can be purchased for about $80.  The science behind UV is very sound, but the actual use has been difficult to say the least.  Knowing these problems and accommodating them closely would allow the Steri-Pen to work well, but care must be taken to accommodate the weaknesses.

vi.Boiling – Boiling is always going to work, provided the water is boiled long enough.  Again, cysts are resistant to boiling for short periods, and most people do not boil long enough for proper disinfection.  A pressure canner/cooker is a good way to effectively boil water with minimal time and energy consumption.
vii.Distillation – A by-product of boiling, distillation is the process of collecting the steam effluent and using it.  The resulting water is perfectly clean, but is even more labor and energy intensive than boiling.  Prolonged consumption of distilled water can lead to a deficiency of minerals in the body.
viii.Nuclear – Nuclear treatment is the process of irradiating contaminates with a short half-life radiation, rendering them inactive quickly and effectively.  This is a burgeoning science that is becoming more popular, and we will be seeing much more of this in the coming years.  It is not suitable for non-municipal use, but the disinfection properties cannot be ignored.


4-Wash-water aka grey water –

a.Grey water is the waste from laundry, baths/showers and cooking.  It is separated from black water by not containing ANY human waste, even small amounts.  The relative clarity of grey water compared to wastewater makes it a much preferred source of culinary water if water supply is tainted, compromised or in short supply.

b.Several common household items can taint grey water and make it questionable for re-use in the garden.  Bleach and borax in small doses will kill any favorable bacteria in a sand filter and root plants.   Most soaps and cleansers are also high in sodium, so a close watch must be kept to make sure the soil in not being loaded with salts, especially in the mountain west where we have a high natural salt content.  

c.Laundry can be washed several times with the same wash load by stopping the washer before it begins to drain and rinse the clothes.  The next set of clothes can then be washed using the same soap and water.  Rinse water can still be used on the garden and the extremely dirty wash water can be used to supply water for toilets.
d.Any wash water from clothes soiled with gasoline or pesticides should only be used to supply flushing water
e.Grey water from food preparation with fats and oils may create problems with build-up in a garden, and should be used only for flushing as well.

5-Wastewater aka black water –

a.Contaminates-

i.Untreated wastewater not only contains all of the above health risks, it also concentrates them into one highly toxic stream or area.

b.Health Risks-
 i.In addition to water-borne issues as mentioned above, wastewater  also presents vector problems, otherwise known as pests such as rats, insects and other wild vermin which are attracted to open sewage.  These pests spread diseases and contaminate, as well as create comfort problems by spreading odors and physical remnants.

c.Treatment –
   i.Wastewater treatment is essentially a large bug-farm.  The goal is to give good bugs the opportunity to eat bad bugs, then turn the tables and let other bugs eat the first set.  Eventually the result is dewatered and solidified and removed from the system.  Although there is a tremendous amount of chemistry, biology and engineering involved, the resulting methods are surprisingly low-tech and relatively easy to operate.  The first step is to allow the flow to be oxygenated as much as possible, and pass over as much surface area as possible.  This allows the first set of ‘good’ bugs to thrive on the surface area in an oxygen rich environment, reducing the loading in the stream considerably.  In practice, this can be something as simple as a streambed with base-ball sized cobble and plenty of water-fall action to mix air in the water.  The resulting effluent can then be discharged into a lake or river if the flow is not too great, relying on the dilution to take care of the rest.  

   ii.On a small scale, a family should dig a latrine and have a supply of lye available to keep the above issues to a minimum.  Care should be taken to place the latrine in a location where it will not contaminate water supplies, create odor problems or create problems with living areas.  Latrines are not permanent solutions and shallow pits will have to be moved more frequently to prevent overloading the area.

d.Solid Waste aka trash – Garbage has the same odor and vector issues that wastewater has, and should be treated very similarly.  A trash pit can be dug away from living areas and water supplies, but in the event of overfilling it must be covered and a new pit dug.  Burning trash in an incinerator is a good option, throwing unburnable items into a pit after incineration.  Contaminates from solid waste are among the most toxic that mankind has introduced and great care must be taken to keep them from reaching water sources- including groundwater.


6-Water Storage-

a.How Much?-
 i.The more the merrier.  Plan on at least a gallon per person, per day for drinking and eating requirements.  Washing and hygiene can be added to this amount and may not require complete treatment, depending on the nature of the emergency.  How many days of storage will depend on your specific family, space and anticipated emergency.
b.Treatment-
 i.Chlorine is the best form of treatment for stored water.  It is cheap, readily available and easy to use.  Only 5-7 drops of bleach (only about 7% chlorine) is needed to treat each gallon of water, this should be barely recognizable by taste.  Remember that chlorine beats cholera and bleach doesn’t taste nearly so bad.
c.Where & How-
 i.Barrels and buckets should be food-grade.  Milk jugs are frequently used, either refilled or purchased new, but these will rupture after 6 months to a year of sitting on the shelf.  Two-liter pop bottles last considerably longer.
 ii.A great place to store water is in the freezer, large blocks of ice help to keep the temperature constant, reducing energy costs during operation.  In the event of a power outage the ice will continue to keep the contents cold long after the outage, and will provide drinking water as they melt.
 iii.Toilet tanks, water heaters and bathtubs (if the outage event can be predicted) all hold clean water for culinary uses.  
 iv.Water storage should be kept out of sunlight to reduce algae growth, as well as away from solvents such as gasoline, diesel, paint and pesticides.  
 v.With 3” PVC pipe is it possible to build a large amount of storage into a wall, under a bed or in other tight areas.  This is a fairly costly way to store water and must be designed to allow venting during use, cycling of old water for new and the addition of chemical treatment.

very nice
covers everything

can this be made so that it doesnt archive?
and just point everyone who asks about water here!

Thanks gents.  If and when I can afford to do so, I would really like to write up a pictoral using many of these methods in the field, unfortunately this would require several hundred dollars worth of products, so it may take some time.

Also, because my experience has been with municipal water I left off a lot of the 'alternative' methods that I have been asked about in the past.  These include silver -colloidal and dollars (dollars were once used to keep milk from going bad before refrigeration was common), grafefruit seed extract, eyes of newt, dragon farts, etc.  Most of these methods are very poorly defined and typically have no quatitative dosage or success rates that I have been able to discover, so I leave them up to the users judgement.  

As it mentioned before, my goal is to make people educated shoppers and preppers, every family should tailor this to their own needs and pocket-books.

I was going to ask about silver as I understand the Romans used silver containers for their water. I mean a few silver dollars are easy to carry and pack.

SCW, Excellent post once again. About a year ago you posted another essay on water treatment that was so informative that I saved it to my important documents file. Thanks for taking the time to share your knowedge. Any experience or opinion on the newer hollow fiber technology that are used in the Sawyer Fiters and MSR Hyperflow?

Full-Auto

Dragongoddess- Silver has been used for a very long time to control spoilage, I'm really surprised that information about it is so slim.  Another effective technique that an old timer taught me way back before I ever went to college was using a copper Chore-Boy in the water storage.  Not the copper plated junk the tweakers use, a real copper one.  After several months (years??) his untreated well-water was still very good.  Again, YMMV.




Thanks!  Send me an email at shane.watson(at)ecislc.com and I'll send you the Word version that contains some other information as well.

Regarding the hollow fiber technology, I'd have to say.....I'm probably familiar with it.  There are not very many manufacturers of these parts but they carry all kinds of brand names.  In municipal settings these (at least these type of filters) are used as MBR and SBR treatment, primarily for wastewater.  Pretty cutting edge for the most part, although they are becoming much more common, and very reliable.  I have not seen the Sawyer/MSR in person however.  I just read the specs on it, they seem quite good (no carbon filter if that matters to you) and the MSR brand is good, so my gut feeling is that it would be a great filter.

I REALLY appriciate people bringing up these products as I'm not around the small scale stuff, in fact I've left the water industry in general for a while.  It's great to see all the stuff on the market.

Great post.  Thanks for the info, SCW.

Great info, thanks!

  SCW excellent info.  Thanks for posting.  I've save the infor to my survival folder.

Thank you.  If you send me an email I'll give you a Word document with all of the above (albeit better formatted) with a few pages of additional information that didn't make it in the post.

shane.watson(AT)ecislc(DOT)com

I have purchased a pretty fair amount of filters and other methods of treatment in the past few weeks, I hope to make a pictoral review of about 20 treatment methods in the spring.  If anyone has a specific request please let me know.

Shane

Shane, thank you for taking the time to post such an informative thread for us.  I was directed here by another ARFCOM'er when he read a question I had about using a MSR filter as a short to mid-term solution in my household should the need to be self-sufficient ever arrive.

Great post- thank you!

tag

thanks for the info

just printed off

You are very welcome.  As I said, I did this for my a prepardness seminar for my church and I figured it would be well recieved here as well.





Don't print that crap!  The formatting sucks and it's missing an entire table on advantages and disadvantages of a everything discussed.  It's also missing design info on a sand filter that can treat water completely without chemicals.  Send me an email and I'll send it to you, mucho better.  shane.watson(at)ecislc(dot)com

EDIT-

At the suggestion of a fellow ArfCommer, I have posted the document to Google Documents, the formatting is much better and all the text is there, but I don't know how well it will print/download.  Here it is, if it's not doing well let me know and I'll just email the document.

WATER DOCUMENT HERE

I tried printing the Google Doc to a PDF file and it's screwing up the spacing. Would like to get the Word document if possible.

Thank you SCW, well done!

Get it quick, because of the Utes win over Alabama I'm offering a one-time get one-get one free.

It looked like the drawing is not getting through very well either.  I had a hell of a time getting that drawing to print well in my paper copies.  It's just an AutoCAD .dwg FCOL.

Prolonged drinking of distilled water will cause nothing.

But then what the fuck do I know, I've been drinking distilled water now for 15 years straight.


There are a lot of mis-conceptions in that write up but, whatever, my opinion.

That just means you are getting your minerals from other sources, probably veggies.  Most people get most of their minerals from their water, RO and distilled are distincly lacking.  Municipal systems that use RO treatment are required to replace minerals to a certain level to ensure people don't wash themselves too clean of them, it's a real risk for a percentage (nearly 100%) of the population.  Good luck....

For what it's worth I'm a Doc, and have researched this and written articles that have been published on water.  My undergrad degree is in Nutrition.

This washing thing you talk of is bullshit.

The body stores minerals in the bones and can liberate some if needed.

There are two forms of minerals, organic and inorganic.  

Inorganic minerals refers to non-vegetable or non-animal matter, i.e. not living. This includes carbonate and lime compounds, calcium, iron and magnesium.  

Because these components are non-living, our bodies can no make use of these minerals and our cells reject them.  

The result of ingesting these minerals is an accumulation of debris in our bodies. Organic minerals living and are found in vegetables, fruit, seeds, grains, meats, and nuts.

These are easily assimilated by our cells and are essential for good health. If your rely on water as the source of your required minerals, you are sadly lacking.

The minerals in water are inorganic, and the body cannot make use of them. The body continually assimilates the much needed minerals from the food we eat.

Arguing with know it all's in this forum is why I rarely post here anymore.

Maybe I should just go away.

I drank distilled water for two years straight at an earlier time in my life.

Presently, I have an RO unit under the kitchen sink for drinking water and cooking which is down stream of a bacteriostatic water softener originally designed by Ionics.

I'm still here and functioning fine

Interesting.  Dispite your abrasive post, I'll make the same offer to you that I have made to everyone I've given the text to thus far.  If you see any problems or corrections, let me know.  Municipal water system are given a requirement for minerals in the water after treatment with RO, we do this for two purposes.  

1- Straight RO/Distilled water is pretty caustic.  It can eat through pipes and fittings pretty quickly as it tries to come to a more natural balance.

2- Health reasons as mentioned.

So-

Given that we are a bunch of engineers who treat water to a specific standard, I don't know or study the medical side at all.  Not my job, I just treat water to a standard.  Could the standard be in error?  You bet, it wouldn't be the first nor the last time policy has been made based on B.S. political motivations or simply wrong ideas.

"I've been doing it for 15 years" is NEVER an acceptable reason to validate anything, but if you can provide some additional information Im more than willing to learn something new.  I've had quite a few people ask about this specific issue and my fallback position is always the water quality standards.  I'd be more that happy to make it more correct based on further info if provided.

Thanks-

SCW - question...

For general poop hitting the fan / couple days in the mountains ... would you recommend the MSR Miniworks or the MSR Miox Pen?

After reading this thread a while ago studied up on the Miox Pen and it worked, but had mixed reviews in practical usage (some people don't like relying on batteries and so on).

The concern people had with the Miox pen were these:
- Taste (some said had a taste, some didn't)
- Time to disinfect (up to 4 hours)
- If the water has lots of particles in it or is cloudy (turbid?), this can be a haven for organisms that are not reached with Mixed Oxidants ... so should be used with a pre filter.

I have some SureFire lights so I got around 40-50 SF CR123 batteries.  Don't really care about taste if survival is an issue ... but the turbid water thing is a concern.

The MSR miniworks had a ton of good reviews; however ... Filters can clog too ... so neither is perfect.

Just wanted your opinion.

Plus 1

I got your email, otherwise it probably would have taken me weeks to find this!

I ALWAYS filter first.  There is a potential for the organizms in water to be shielded/shrouded by stuff in the water, especially clay particles.  The larger the particles makes it more likely for the organisms to be shrouded, but it also makes it easier to filter out the particles.  Again, filtering first will also effectively lower the required contact time for a MIOX system, if you have filtered correctly there shouldn't be any cycsts left in the water, therefore you should be pretty good with a MUCH shorter contact time.

In short, both the filter and the disinfectant are required for complete treatment.  Do you really need the MIOX?  Most of the time not but it's great for the what-if situations.  If you are just in the market for one, get the filter.  Later you can get a replacement filter cartridge or two for the filter.  Then maybe get the MIOX, that's where I'd rank the importance.  MIOX is only important when you are concerned about human-borne issues in the water, like raw sewage.  Even in that case you'd want to filter it first.

I spent a lot of years designing water treatment equipment - mostly very high purity stuff (like for washing semiconductors). I can assure you that very pure water is somewhat corrosive. Water is a very good solvent, and it wants to dissolve things. It will even dissolve stuff like stainless steel to a certain extent. Plastics of some kind work best.

I have heard, but cannot confirm an earlier poster's claim that RO water is required to have a certain level of mineral replenishment when used in municipal supplies. Not sure why, but suspect it is an attempt to protect piping systems as much as anything. It may also be to reduce the amount of lead from lead soldered copper pipes that dissolves into the water. I have also heard the thing about it leaching minerals from your body if you drink it. Cannot confirm or deny that. But a lot of RO treated water is sold as drinking water, and no mention of adding minerals back into it.

You want some amazing coffee? Get yourself a coffee filter and some ground coffee and pour some very pure (like 18+ MOhm) water through it and then heat that up in a microwave.

We were told of pure water being corrosive to systems when I was in school, but we never designed around in when I was in the industry, probably because we never really got 'pure' water.  The only large-scale RO plant I know of in the state mixes with conventially treated water at about a 30% RO to 70% conventional ratio- but that's mostly due to the high cost of RO treatment compared to the required amount of water.  It's also part of a settlement with a local mine in regards to their impact on the water supply, so a lot of issues beyond the actual minerals.

With regards to bottled drinking water, just remember there are no (NO!!) standards for bottled water.  I find that strainght RO water tastes kinda flat and many bottled water brands have added minerals for taste.

I'd love to try the coffee, but in the microwave?  I've never liked microwave coffee, and it seems to get cold faster (or am I just nuts?).

While I don't have a need to wash semi-conductors I would like to RO my new surface water when it arrives.

As the Home Depot type is ineffective, what or where do I want? where to go?

Any links appreciated

Just lookin' for drinking water and plumbing to the ice maker, not needed for the whole house

thanks

(great write up BTW)

The HD/Lowes RO units are not 'ineffective', just not really RO.  If you get a unit from the box store make sure it includes (or at least requires) a pressure tank and waste drain, plan on spending several hundred dollars.  Also, this will still not be a true RO system that filters water on a molecular level, but it will be *pretty good*- about like a backpacking filter.

I found this a couple of years ago

filter making


Is a true RO unit not affordable?  I would like to get something that truely does a good job.

Cool post. Tack it.

Not really needed or affordable for home use, I'm not really sure if you can get one that small, but I would imagine there are unit out there.  Why do you want that level of treatment?

Send an email to shane.watson(at)ecislc(dot)com and I'll give you a document with a similar design as what you posted.  It uses a 55gal drum rather than a concrete case, but same principle.

SWC,

Thanks for the reply.  One more question.

IF I end up getting the miox, what is a practical / sustainable way to prefilter the water for particulates?

For example, I read a Millbank filter would pair nicely with a miox - and from what I understand - its just a mesh bag you roll up / reuse and lets the water drain out the bottom.

like - could you use a coffee filter to prefilter for a miox?

For those wanting to treat larger quantities of water, here's a discussion about how to apply RO filtering at relatively low cost, without the tank [which is only used in normal installations as an 'accumulator' for convenience filling up a gallon or so container quickly -and isn't necessary]. My SO is filling up our storage bottles as I write this w/o a tank.

Low membrane differential pressures -obtainable by siphoning with a head of 15 feet or better, work fine but with a reduced thruput.

The RO elements in the box store kits are true RO membranes. The box stores do have simple charcoal/carbon block filters, I'm not referring to those.

The cost of setting up a small portable system can be kept below $75 with careful shopping.

I posted a few days about RO systems at Lowes being on sale for IIRC $117 or maybe $147. A few months ago, Sam's had a clearance of true RO systems [I posted about it here] for about $80 IIRC and I stocked up.

http://www.ar15.com/forums/topic.html?b=10&f=17&t=577038

You have mail SCW. Thanks for the good info.

A coffee filter is about 15 microns, so it's going to let a LOT of stuff through.  Like almost everything that's not stuck to a big chunk of dirt or moss.  I'd never seen the Millbank bag until I looked it up after reading your post, but to some extent a filter is a filter is a filter.  Look at the pore size and then just make a judgement about which particular brand/construction suits your purposes best.  I use an MSR Sweetwater for hunting/camping type stuff, and I have ceramic filters like a Berkey, two of the Monolithic ceramic filters, a Sawyer and I don't know what else.  They all have plusses and minuses.  MIOX just does a VERY nice job of batting clean-up in my opinion, and it will also hit the grand slam when you need it to- given the right conditions.  By that I mean it's the only one I'd trust if I had no way to filter, but I'd much rather filter first.

Yep.  I actually wanted to include much of the work that EXPY37 had done here, but it was getting kinda long and dry (pardon the pun) so much of this got clipped from my document.  The RO systems from HD/Lowes/Wal-Mart are not true RO- but that's OK.  You (usually) don't need *true* RO, just clean water.  I actually don't have this set-up myself but it is a perfectly valid way to treat your water- usually to a half micron or a little larger, like a good backpacking filter only faster, easier and with the ability to treat a lot more water volume over the life of the filter(s).  The cleaner the source water the better, faster and longer these filters will work- like any other filter.

Again, if you are worried about human-borne viruses or really nasty stuff in the water, you will want to disinfect after filtering.  I've never encountered that condition yet.  I would consider this a problem on safari in Africa, in a flood where the water supply has been compromised or camping where again, the water supply has been compromised with poor sanitation.

For clarification, RO is a membrane where the pore size is about 1.5 times the size of a water molecule.  Because the fabric is hydrophylic, the water hugs the fabric along the face of the filter, and around the corner into the pore 'tunnel' (remember on a microscopic scale the pore will look like a tunnel to the water molecule).  As the water hugs the fabric, it pushes any particles/molecules that are not water away from the fabric such that even though a (for example) salt molecule might fit in the pore space, it can't get into the tunnel when the water keeps bumping it back out.  An RO system must waste about 50% of it's flow to properly get rid of the non-water molecules that are being pumped out.  Any system without a waste is either letting everything get through, or letting the crud plug up the filter.

Most home filter systems operate very similar to this, only because RO requires a lot of pressure, they open up the pore size a lot more and use the buzz-work Reverse Osmosis to sell it.  The pressure canisters required to hold RO filters become expensive, as well as building the pressure required to get the water through the very tight popre size.  Not only that, but most of the time we really don't need that level of treatment anyway.

Here's an illustrative diagram relating particle size to various common materials. Note the bottom scale is conveniently defined in microns, directly relating to measurements we're already familiar with ––for hiking, Berky, ceramic, the new Sawyer filters, reverse osmosis, etc.







Note that the RO filter is on the far left of the chart and the far right relates to coarse sand as a filter media. A pin "point is about 80 microns and viruses can to be as small as .002 microns according to the chart. An RO filter pore diameter approches the the radius of an atom. Pretty danged small.

A sugar molecule is at the limit of being passed by an RO membrane, of which there are several kinds of membranes designed for different applications.

Processing brackish water requires pressures around 350 psi for efficient flow because of the type of membrane used, non-brackish water can be processed at around 40 psi, and as I have reported, at a considerably lower pressure albeit with much less flow.

Interestingly, the hollow fiber filter membrane that is used in the new hi perf Sawyer filter, being discussed in another thread, appears to be another form of a reverse osmosis 'membrane'.

The 10 inch standard RO membrane cartridge used in household RO installations can be purchased in various flow rates and in several materials depending on your specific application. They are available in 20 inch and larger sizes for institutional use.

Here's one similar to the one we're using at our location, it has a pore size of .001 micron [not too much smaller than the high performance Sawyer hollow fiber filter and it's designed to be tolerent to chlorine.] Note that the price is a complete ripoff for uninformed consumers.

http://www.advancedwaterfilters.com/filter-products/reverse-osmosis-membrane-cta.html

This chart is handy to print out and refer to in discussions of different kinds of filters especially when making a decision which is best for your needs.

Temperature of the membrane is directly related to the flow efficiency.

Also note the difference between "suspended" contaminants and "dissolved" contaminents. Dissolved contaminants won't be filtered out by ceramic and larger pore sized filters. Generally you have to use RO to remove dissolved substances at the atomic/molecular level.

A carbon block filter inline to other stages works well to adsorb some dissolved materials.

ETA One last issue.

There are reports of bacteria being able to "grow through" the pores of some small pore filters. Filters that are used occasionally seem to have the problem, filters that are in constant use are reported to be less susceptible. Chlorine treatment of the input supposedly kills the bacteria.

Lowes has Reverse Osmosis kits on sale for under $150. Not that great of a price but something to look at.

BRD, why are you thinking HD RO filters are ineffective?

They certainly are effective.

But there are better prices elsewhere for essentially the same thing. See my thread on RO.

Tagged.  Excellent post.

The RO units sold at lowes, etc are indeed RO units.

because they operate at low pressures, they have some design compromises. one of them is they don't have the recovery rate a higher pressure RO has.

they also have to be able to deal with the relatively high level of hardness they may see from well water, so that also pushes them toward low rates of recovery.

bump!

I got a lot out of this thread so I'm bumping it again.

Btw - I got a MSR miniworks and a camelbak filter adapter so I can remove the bite valve and reverse fill my camelbak without having to unscrew it.  I may add a siltstopper to the inlet to extend the life of the filter - maybe not.  I hear if you put one of those on you don't end up needing to clean the ceramic filter nearly at all.

Any suggestions for using my well water in an emergency? The situation is that even if I can get some water out of the well (method irrelevant right now), I'm next door to a golf course and I expect the water to be FULL of chemicals/pesticides, etc.  Is there a practical method to make such water useable in an emergency (either short term or long term)? I get the sense that charcoal filtration isn't going to work as well as I'd like.

Berkley filter or something else?

This is an excellent thread.  I think a lot of people overlook the importance of water in a catastrophic event.

Bump, nice info!