Sand and Gravel Water Filter

Boy Scouts do this, probably for a merit badge.

Is this for drinking water? Or fun?

My swimming pool filter uses sand to remove particulates, but it doesn't remove bacteria. That is done by adding chlorine.

not too get too complicated....but a good RO filter will also remove the lil bugs, a charcosl filtrer goes a long way to improve taste

The kid(s) want to drink it if they can. Who knows where they want to take the 'uncleaned' water from .

This set up just gets rid of "hard matter", not bacteria like what would cause dissentary or other gut wrenching ailments Correct?

noe you're scaring me, Google chlorine and iodine to get "contact times" required to disinfect water

My advice is to definitely NOT let them drink this water. There's a big, BIG difference between filtered water and purified/drinking water.

Without getting too technical, filtration removes particulates, and some other stuff that is big enough to get caught.

It doesn't remove all the bacteria and viruses.

It's a good outdoor project and if you start with safe water it'll be fun.

Greetings from Belgium, the land of 2000 beers. Famous high alcohol beers are brewed with these filters where pond water is used through a sand/gravel water filter and an additional carbon filter. (wood carbon) They taste very good, probably the alcohol takes over the disinfecting function? (better taste than chlorine?) Monks invented the beers to keep water safe in times of typhus, pest and cholera. And invented cheese immediately to keep milk for a long time. Is the combination beer and cheese just coincidence?

Bon voyage.

What happens when you run out of beer? Brew 2000 more?

Sorry about answering a question with a question. What are they inducing into the filter and what do they want to end up with?

I have filtered a lot of fluids this is usually where the discussion starts. (We will skip the volume and flow rate for later)

Depending on the source of the water, a simple sand and gravel filter is generally NOT adequate for preparing drinking water. One also needs to consider the sand and gravel- just digging it up on the beach is not good enough. Normally, one purchases commercially-prepared sand and gravel. As noted by others, the sand and gravel will only remove particulate matter. There are a whole lot of other natsty things that get in to water that have to be dealt with before it is safe to drink (not just bacteria and viruses- you also have to think about chemicals such as agricultural runoff or air polution from automotive traffic- especially if the water comes from highway run-off). Anyone dumping raw sewerage upstream from where you are collecting the water?

Step 1- get a chemical analysis of the water. Then figure out what sort of treatment you need...

you clearly have experience but I think you flew right past the spirit of the guys question, I might have misunderstood him. I don't think he wants to build settling ponds and excavate down 6 feet or more, it sounds more like a weekend project for him and his grand kids to do for fun.if he was just going camping or back backpacking and wanted a safe drink I'd recommend one of these......but I think he wants a project a

Yeah I flew by quite a bit, didn't I? LOL

If the kid is looking for a water filter when back packing in the wilds, then he ought to purchase a Katadyn "Vario" water filter.....not at all cheap, but if your life is on the line in the wilderness it can mean life or death. Lightweigh and extremely easy to use....but you need to read the instructions carefully, otherwise you can break it of misuse it!

I have one of these and they work great. I still disinfect the filtered water with the water purification tabs or household bleach (unscented) just to play it safe.

Use three grades of filter material not just sand and gravel. The sand layer on top will be too fine so it needs a courser layer in between the sand and gravel to stop the sand being washed down into the gravel. Typically 30-35% top sand, 15% course layer, 50-55% gravel.

Make sure that there is a method of distributing the inlet water evenly or the sand will "rat-hole" at the point where the bulk of the water hits the sand.

The sediments in your raw water will build up quickly and form a skin that will reduce flow. Think about ways of skimming this off. A backwash system introduces clean water at the base which floats off the scum allowing it to be flushed away but this may be a little over the top for your set-up.

A woodsman's trick is to cut the base off a soda bottle (some carry a funnel shaped canvas bag for this) and hang it upside down half stuffed with moss as the filtering agent then top it up with water. Leave a pan underneath overnight to catch the filtered water. This will provide enough to allow a few cups of clear water for a breakfast brew-up.

The kids can drink it but they must boil it first.

To improve it a bit, add some fermented potatoes and bran, boil it in a closed vessel and collect the condensate. It may not taste much better but after a few cups they won't care. Caution this may turn the kids blind.

What you're talking about is basically a medium or rapid multi-media water filtration method...

This is what I was talking about earlier:

http://en.wikipedia.org/wiki/Slow_sand_filter

I made a filter to use with our aquarium because our pleco puts out a lot of waste and bits of food. the filter I paid good money for helps but still leaves a lot on there. instead of changing out much of the water weekly, which is bad for the fish, I took a piece of 2.5 inch pvc pipe and put a fitting on the bottom with several pieces of round 40 mesh stainless discs I had from a previous project, put some of that filter foam stuff in on top and added an inch or so of charcoal then about 8 inches of sand, then another piece of the foam on top. I siphon the water through this into a bucket then put most of it back into the tank. it comes out fairly clear (not sure if potable) This reduces us to about 25 percent water change weekly. Might try something like this though hindsight I would have used a three or four inch pipe about 2 feet long as the smaller pipe is slower.

Shouldn't that be "activated" charcoal?

maybe his fish are fans of BBQ

All good answers.Further investigation turned up a basic school type project. No drinking anything. Just an experiment of sorts on basic "clean water" in nature.

Why a mountain stream is so clear and a Louisana bayou is soooo dirty.

thanks all.

A huge bead filter like is used in aquaculture would have been my best guess for really clean but as you all state, it does NOT remove the bacteria that could harm humans.

A good particulate filter with a good charcoal filter will render water relatively safe. By this I mean if you depended on it for survival it would suffice, but still not 100 percent. If you were in dire need of drinkng water then boiling it is the best. If I were in need of drinking water in a survival situation I would likely filter through sand and charcoal(if available) then boil it. Of course if I had materials I would also distill it. Depending on your needs these are all effective methods. Drinking water out of a puddle that has been boiled is good, but sediment would likely make it taste like chit, so there comes the filter to take the chit out of it.

I'm not endorsing this product because I have a business stake in the company, but rather it is one of the best on the market. It uses GAC for eliminating odors and bad tastes. Also, it employs a ceramic disc filter.....just make sure to wrap a paper coffee filter on the end of the suction tube to prevent uptake of sediments. Hold it in place with a rubber band.

http://www.katadyn.com/usen/katadyn-products/products/katadynshopconnect/katadyn-water-filters-backcountry-series-products/katadyn-vario-1/

These are commonly used in large outdoor fish ponds to remove the particulate waste from the fish, With a follow up Algae Tank to remove the ammonia and urea wastes.

A mate of mine uses this set-up for his Koi and other fish ponds.

Regards,
Sapper

A fairly common field expedient filter

How to make a water filter

Knowing how to make a water filter is important, if the only water you can find is dirty muddy water. There are a number of different ways to make a water filter. One simple way is to use sand. Sand is nature's way of purifying water.Simple sand water filter1. To start with, you need a container. If you can find a large, empty can, use it. Punch 5-10 holes in the bottom of the can. A large plastic bottle is also fine. Cut the end of the bottle off evenly. If there is no container available, you have to use what material that nature can provide, or that you brought with you.If you find a birch tree, make a cone of birch bark. The cone will need to have a fairly small hole in the bottom. Tie the cone with rope to keep it from opening up. 2. First, you need to stop the sand to get out of the container. Find some filter material you can place at the bottom. For instance:• a couple of inches (centimeters) of pebbles.• a grass mesh, make sure it's nonpoisonous grass.• or cotton material.3. Add a layer of gravel. The main purpose of the gravel layer is to strengthen the filter material and prevent sand mixed with the water you get from the filter.4. Fill your bottle or cone with sand.5. Collect some water. Pour your collected water through the filter. Catch it in another container at the bottom. Look at the water that comes out of the filter. It should be clear. If not, you may have to pass the water through the filter more than once.Safe waterNow you know how to make a water filter, but to get safe water to drink, you also have to purify your water. The water may still contain harmful bacteria that your filter did not remove.To improve your water filter, add a layer of charcoal between the gravel and sand layer. Get charcoal from your fire, crush it, not to powder but just fine gravel size.

What we have here, is failure to communicate, again.

While your post describes a way to filter water, it does not describe a way to purify that water. It also does not cite the source of your post. A citation/link would, make your post legal, and allow anyone wanting to review it the ability to see the references/bold type included in the post.

Following this post will not yield safe drinking water, unless it is already safe before being "filtered" by your method.

Through no fault of yours, this thread has morphed into a method of commercial/municipal filtration, filtration of water using modern personal brackish water filtration equipment and filtering fish pond water and maybe some other off topic methods I forget, while not contributing anything in the way of a backyard, afternoon project.

The OP's grand kids want to try to clean some water in the back yard, using sand and gravel. Nothing more, nothing less.

True to form, the members here cannot leave well enough alone and just suggest some fun things to do to purify water. We want to get really technical when it is not required.

Don't take my rant personally, it is directed at us all.

Happy Holidays.

Media filters are more-or-less standard practice in the water industries - usually the first in a number of stages of processing to make potable water.

I would argue about filtration being the first stage. Any coagulants (like Alum) are added upstream of the filters so that the filters will remove any coagulated products.

Thanks for the clarification.

pdf file link to text and youtube link to wmv file given below
ebookbrowse.com/barrel-biosand-filter-pdf-d316202404

29 Feb 2012 - Download Barrel Biosand filter.pdf documents from www.rcsdin.org at @EbookBrowse.barrel biosand filter.pdf

and

www.youtube.com/watch?v=I1t2hhoqpaQ

Nov 20, 2011 - Uploaded by rcsdin

Safe potable water considered a basic human right and an essential for achieving gender equality, sustainable ...

Once again, thank you all. I have enough info to help them make a small Show-n-Tell gadget for the school project.

Thank you all and a Joyeaux Noel !