S.O.B.! Help!

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I wondered where you'd got off to. . . It's real good to see you back.

Anyway, remembering your past post about a water tank, I'd like to pick your brain some and since the info may be useful to others here, I'd like to do it in public.

I've got a piece of concrete sewer pipe about the same size as my 1000 gallon propane tank. It's never been used, and I'd like to explore the idea of using it as a water tank.

It is currently laying on its side, and I would think that the easiest way to utilize it would be to stand it on end in a concrete base with plumbing embedded into the concrete, and cover the top with a septic tank cover. That may or may not be a good idea, and I'd like your comments.

Also, I have heard that there are problems with using concrete tanks for storage of drinking water because of some chemical contamination of the water. This doesn't make any sense to me off the top of my head, but I'd like your opinion here as well.

Another point that I'd like your knowledge about is freezing. How cold would you think it would have to get to freeze the contents enough to damage the tank, if it was full, half, etc.? In other words, how well will the concrete insulate the water from the outside air?

Knowing that you have some considerable experience here, anything else that you can think of to add would be greatly appreciated.

Finally (and this is just hoping that you or anyone else on the forum might have a good trick up your sleeve), lacking an industrial crane, how would you go about getting this monster-heavy pipe up on its end?

-- Hardliner (searcher@internet.com), March 25, 1999


Put htis in "New Answers" so S.O.B. will see it before he leaves again. . .

-- Hardliner (searcher@internet.com), March 25, 1999.

Hardliner, I have absolutely no experience in these matters, so naturally, I feel compelled to respond.

If you're worried about chemical leaching, you might want to consider a pond or pool liner. Real Goods sells pond liners.

With regard to the pipe, how long and wide is it?

I saw a show on Discovery channel a year or so ago where they were trying to recreate the raising of ancient obelisks. That would show you some techniques for dealing with standing unwieldy stuff on end.

If I recall right, they got the obelisk up on a ramp that was maybe 30 degrees and then used a gin-pole set up to try to raise the obelisk vertical on its base. They failed, but the obelisk was huge.

I can't remember how they got it on the ramp. Maybe by continuous insertion of small wedges underneath.

What about a front end loader?

-- Puddintame (dit@dot.com), March 25, 1999.

Another .02::

1) Consider a chopper gun fiberglass coat for inside if you know any fiberglass folks (pool installers, etc).

2) dig hole under 1/3 of pipe, install plumbing, pour concrete, let set, screw jack for the high end and tilt into place with perhaps a dozer or tractor to hold it BACK rather than simply dropping it in.

BTW, you can probably bury half or more of it this way and cut down on the freeze problem.

3) the concrete will not do a lot for insulation. You will be working with the cooling rate of a given mass in air, which calc's I haven't done in a couple decades plus. You can slow this down with a spray on coat of the stuff new propane tanks are coated with (It's some kind of poly or rubber), or you can house it and fill the house with fiberglass (loose or batts).

Chuck, always willing to be unhelpful, just don't ask. ;-D}

-- Chuck, a night driver (reinzoo@en.com), March 25, 1999.

Hardliner: why turn it vertical? Dig an angled trench next to it, and roll it in. Although you lose a little storage due to the angle, depending on the length, shouldn't be more than 10% capacity. Easier to cover, too, for insulation/privacy. As far as potability, not sure, but you can always have it as back up for desperate times, or for cleaning, flushing, irrigation. Water is better than no water, usually.

-- Spidey (in@jam.com), March 26, 1999.

Spidey, you missed the fact that it wasn't capped. He needs to cap both ends. Setting it on a pad and then capping the top is INFINITELY easier than trying to secure a cap on both ends, with the plumbing included in one of the caps.


-- Chuck, a night driver (reinzoo@en.com), March 26, 1999.


I would be a little careful. I don't know where you're located, but where I live it gets -20 in winter. Because of that cities that use buried resevoirs have concrete 12 - 18" thick. Not only for strength in holding water, but because a little freezeing or especially heaving of the ground (if you bury it) can break concrete. If your pipe is only a few inches (less than 6) thick theres a good chance it will crack in weather extremes. Sewers don't worry about this because: the pipe is kept warm by sewage, and if it does crack, the cracks are more or less sealed by debris.

As someone indicated, concrete is a very poor insulator. Your idea still is possible, but it will definitely need a little attention to details.

Good luck to us all.

-- Jon Johnson (narnia4@usa.net), March 26, 1999.

Now, remember, I drink my tap water straight up with ice from the freezer - so I'm not what you might call a "pure water purist," but it appears to me that you should be able to use the thing as emergency ervice tank - the size is smaller that you may think though - maybe 100 gallons? Two 55 gal "food service" drums probably would hold more - at much less effort. ID, length?

Water is delivered to cities via concrete lined tunnels - so by that example, leachate from the conc itself is not likely a problem. Clean it thoroughly while horizontal with no end to facilitate flushing..

Sealing the ends? You have two different problems - the lower end probably easiest resolved by digging a hole and trench - lay your "supply pipe" through the trench, into to the hole, then "up" a few inches. (cap it temporarily - but be able to remove this cap after the tank is in place from the top of the tank. Rope, string maybe?) Pour enough concrete into the base to do several things - be wide enough to be stable - decide on your soil type, height of "tank", distance "into the ground" the tank will sit, then how much "side pressure" you get by backfilling the hole. Regardless, pour at least 3-4 inches of concrete deep - probably 4-6 inches wider than the pipe. Tip (as they described above) the pipe down into the concrete, but don't let it settle through the concrete to the dirt. Done - the bottom joint is sealed. Add extra concrete around the outside. Let dry, then remove the outlet pipe cover from the top of the tank. If you try to remove the cover before the concrete has completely set, the pipe will tip over and destroy your work. Don't work the concrete too much - else it will settle in from the outside up into the inside.

Make a "tight" top cover to keep bugs, rodents, birds, mice, and leaves out of the water. Don't try to fill the tank from rain water - the little water you get will be out-numbered by the atmospheric dirt and soot falling in. Evap losses will exceed rainfall and snowfall - unless your're in the Pacific Northwest.

Site planning - the outlet pipe, if possible, should be above your kitchem sink to allow gravity drain and a regular cutout valve, not a pump. If not, go back in the trench and add remaining plumbing and pump. If water level in the tank is "above" the drain valve - it will flow naturally.

The tank should be on the "clean" uphill side of the house from the septic tank and outflow piping. Check with your county extension service or water dept.

Freezing - the pipe has smooth inside walls and doesn't have a "pressure tight cover - if (when) the water freezes, it will push the top layer of ice "up" as lower (warmer water in contact with the ground) cools and freezes as the air in the tank cools. If the whole thing freezes, you have no water coming out - the drain pipe will be your difficult point if it is not at leat 12- 18" down.

Don't recommend coming out the side - you'd have to cut through the wall of the tank, reseal the hole and the drain pipe, and that's not easy. Also, you'd lose the water volume below the drain pipe.

-- Robert A Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), March 26, 1999.

Thanks everyone, for the responses. I've done some measuring and some calculating and have a few facts to add to the problem.

First, the pipe is 3 feet ID and 40 inches OD, and 13 feet long. As Robert noted, it is smooth inside and rough outside. By my calculations, it should hold 687.396 gallons and the pipe itself should weigh somewhere between 3741 and 4181 pounds.

Both the pipe and the well that I intend to fill it from are on the hill behind the house and several feet above even the showerheads in my house. The septic system is several hundred feet away and well downhill from the well-house.

The frost line here is about 4 inches down, but those are basically 4 inches of rock. The hill is mostly rock, with a thin covering of dirt in some places and in the crevices in the rock. When you dig post holes here, you put a rock bit on the auger, park the tractor and come back after lunch. I suspect that I could make a hole for the bottom of the pipe, but it seems far more practical to up-end it and then push rock and earth against the bottom several feet for stability.

As to the plumbing, your advice, Robert, about not cutting through the side has almost certainly saved me from a major mistake. Although I don't want to go too deep (because of both the difficulty of digging and the height above the house plumbing), I see the inherent superiority of your method.

It seems apparent that the suggestions about getting the pipe upright were all made with a much lighter piece in mind. Although I can imagine a rigging using hydraulic jacks, "come-alongs", wedges, ramps, chains and my tractor (an ancient Ford 8-N), I think that in the interests of safety and possible consequences, I'd better plan on hiring a truck with a suitable crane for that part of the job.

I would also think that the concrete base had better be reinforced and cured before setting the pipe onto it. I don't see how wet concrete would even come close to supporting that weight on a 40 inch circle 2 inches thick. Robert, I suspect that you can answer the concrete stuff; does it have to be set into wet concrete or can I get as good a seal afterward? How about casting a circular groove into the base and then setting the pipe into that after the base had cured?

I'd also like to fill this thing from the top, so that the pump doesn't work against a steadily increasing load. I'd also like for that "fill" pipe to be inside the tank, for physical protection. That means that I'll have this 12 foot plus pipe sticking up in the air that I have to lower the big concrete pipe down over; again, that sounds like a job for a real crane.

Taking your comments, Robert, as meaning that if the water in the tank does freeze, it will not break the tank but simply push a "plug" of ice upward, can I count on a concrete cover (septic tank lid) not falling off if that happens but simply "riding" the ice up as it freezes, sitting on top of it and riding it back down when it melts? Getting such a cover on top with the aforementioned crane will be no problem, but if I had to do it without, I'm not real enthused about the idea (picture me trying to climb a ladder with a 4 foot diameter disk of concrete that's 3 inches thick!). Of course, that would only happen if the tank was completely full, and it might be easier to simply not fill it that much in the cold parts of the year.

Given that cutting through the side of the tank is not a good idea in any case, would a pressure gauge on the outlet plumbing be a viable way to determine the height of water in the tank? (I know it would theoretically, but I have no idea if a pressure gauge suitably calibrated is available)

My bottom-line question about this project is: Is the effort to implement and durability of the finished product consistent with the utility it will provide? I'd welcome comments on that from all, as well.

-- Hardliner (searcher@internet.com), March 26, 1999.

At that size, and because you can build it and fill it above the house - so you won't have to go outside in the cold to pump water, and because of the absolute advantages of getting that much pressure head in the kitchen, bathroom, and toilets with only a little effort - go for it.

Use a wood lid - no need to be concrete to be "dirt proof".

Ice expands 9-11% I think (90% of an iceberg is underwater - so invert the density to get volume expansion.) Just leave a 12" margin at the top.

If you have the conc lid already - use it as your foundation - thus you have a "slab already built" that will carry many tons of compression loads. If not, dig and pour first - since it is into rock (not clay or loose soil) the "support" part is simplified and the margin around the outside is reduced.

Either way, you're apparently left with a "sealing" problem around the base and inlet pipe and outlet pipe 9if the inlet pipe is also from "inside" the tank - regardless of whether you are on either a poured slab, rough rock that "adequately flattened" to keep the thing upright, or the "lid" - make a couple pounds of mortar or very small gravel aggregate concrete - the slab concrete for example would have 1/2 - 3/4 inch aggreaate - get a finer mix ideally (or use slightly more of the 1/2 aggregate concrete). Anyway, fill the "bottom of the tank to at least 3/4" higher than than the joint between the tank and the bottom. If the joint is "exposed" (not in a slight hole) make a outer form to retain the wet concrete as it works its way out throught the cracks. If it is tank is sitting in a slightly hollowed out hole - use the walls of the hole and the dirt as a dam to hold the wet concrete.

Jump in - wearing old rubbers or wading boots - and smooth the concrete out - working the stuff so the smooth concrete works it way under and out between the bottom and the "outside" form. Use a good trowel with a point to get a smooth surface at the seam - as you work the concrete mix the water and cement will rise anyway. Make sure you have an overlap of the new bottom and the walls. That overlap is your joint.

The concrete "outside" should be smoothed by your helper outside to make a backup joint as you work the inside. If you remain inside while the outside is worked, you can add concrete or move concrete to correct any problems. Your vistors will only see the outside, the water will only see the inside. You decide which is more important in the future.

When you get the floor smooth - climb out - you did remember the ladder right? Remember also to minimize disturbing the walls as you climb out - some movement probably isn't a significant problem - but you do want to keep that joint as smooth as possible.

Once dry, this is a rigid joint - so may over time devleope slight cracks and leaks. These should be neglible, but don't be surprised if they develope. Could be a slight discoloration or algea if they persist. A commercial concrete pipe contractor might be able to recommend a permanent rubber seal or gaket that could be used - but I'm not sure it's worth your while even to investigate.

Tilting it up? Hmmmmn. Gonna have to think about that one. Got trees? Rope? Come-alongs? Seems like you've got a mobility problem (roll it/move it to the right area) and a tilt-it upright problem.

Insulation - wrap it with 3"-4" insulation blankets to reduce heat loss to the air, then with black plastic to increase heat gain from solar. remeber to cover the roof too with black plastic.

-- Robert A Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), March 26, 1999.

Let's see, 13 ft. tall, 36 inch inside diameter, hmmm, is CO2 heavier or lighter than atmospheric mixture? Got snorkels?

-- Puddintame (dit@dot.com), March 26, 1999.

Forgot about the fill pipe - if you have two small pipe stubs sticking up 3-4" above the bottom seal concrete- wait for the seal concrete to dry - then climb back inside (you did remember to remove the ladder before the concrete dried right?) 8<) and finish extending the fillpipe to near the top with a connector and a new piece of pipe. 36" is plenty of working room.

If you *securely* fasten a 4x4 sized lumber to the bottom of the pipe - perhaps one 6-8 ft long - and then use the lumber as you pivot point - the lumber will prevent the cylinder from "rolling" as you work to tilt it up. This will give you more control to "pull" with the tractor or come along.

To rotate, the cylinder will need to be anchored to prevent it from "skidding" as you pull it. Anchor the lumber with a couple of posts into the ground. The cylinder than can be pulled horizontally - and the cylinder will pivot about the axis of the timber at the point where the timber hits the two anchor points. So plan these two points so the cylinder will land inits final position when it is vertical.

Be careful - you are uphill of the house - if the timber breaks free, and the concrete isn't secured with a backup chain - it may roll downhill and hit the house. You will have try again - and your wife WON'T be happy with the new "picture this" window.

-- Robert A Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), March 26, 1999.


Air = 80% N2 and 20% O2 (near enough) = .80*28 + .20*32 = 28.8 average molecular density.

CO2 = 12 + 32 = 44.....

- so either hold your breathe or put a little fan at the top pointed down into the tank. Get some scuba operator to figure safe time in the tank at the bottom, then divide that by two as a safety margin....

-- Robert A Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), March 26, 1999.

Hardliner, Cut the pipe in half and buy a few more plumbing fixtures.

-- Puddintame (dit@dot.com), March 26, 1999.


I wasn't ignoring your questions Sir, I was just pretty busy.

The most obvious reason not to use the pipe for a tank is that you, (I), don't know what the specifications of the cement was when it was mixed. That is, what it's rating is. There are, as you know, several different "mixes" of cement and, depending on the rating of this particular pipe, you may have problems after you sweat it out and do all of the preparation work only to find yourself with a broken tank because of the water weight.

This is, obviously, most significant if you were to stand it up on end. Most sewer pipe is stress loaded for less than the weight that you will be looking at with a full upright pipe. Normally sewer pipe is buried underground. The dirt cover serves to spread out the surface load on the pipe to several square feet of earth surrounding the pipe, which allows you to MOMENTARILY load the pipe by driving your truck/car over it. As an exposed tank you don't have that luxury and the full water weight will be brought to bear on the pipe walls.

You didn't say just what size pipe it is but here are some basic calculations to point you in the general direction.

Water weighs 8.333 pounds per gallon.

There are 7.48 gallons in one cubic foot of water

There are 144 square inches in 1 square foot of area

The area calculation for a full pipe is: Pipe Inside Diameter Squared times 0.7854, That is [ ID x ID x 0.7854 ],

OR - PI times the Pipe Radius Squared, which would be {0.5 ID x 0.5 ID x 3.1416}.

Either calculation will give you the same result.

The result will be in whatever units that you use as the entering arguements, feet or inches.

Example: A 4 foot (48") diameter pipe that is 10 feet (120") long would calculate out as:

4 x 4 = 16... 16 x 0.7854 = 12.5664 square feet of circular area. There are 7.48 gallons of water in each square foot of area, so you will have 12.5664 x 7.48 = 93.997 gallons of water in each foot of level in the pipe when it is full (or if it is upright).

SO: a 4' x 10' pipe would have approximately 940 gallons in it when it is full.

Since water weighs in at 8.333 pounds per gallon, you can see right away that you have some 8000 pounds of weight pressing against the weakest point in the pipe on the bottom end. If the pipe isn't stressed to this weight bearing, plus whatever safety factor you feel is necessary, you will have a catastrophic failure of the pipe. Additionally, there would be a risk of it falling over if it wasn't very stable in it's footing since it would be 2.5 times as high as it is wide, or if you do not have an extremely well drained site where the ground slopes away from the tank area in all directions. Erosion can do wonders to anything you build, so drain the site as well as you can.

Unless you just want the head pressure for drawdown purposes, ( 0.43 PSI x elevation in feet), you would probably best be served by leaving the pipe laying horizontally, slightly elevated at one end, and just using a gravity drain system with it. A masonary drill bit can be used to drill two holes in the pipe, let's say 6" in from the ends of the pipe will allow you to put a piece of Stainless steel "all thread" through the centerline of the pipe. Rubber washers and stainless steel nuts on both the inside and the outside of the all thread as it passes through the walls of the pipe will provide the seals necessary for the water and allow for the attaching of the straps used to seal the ends of the pipe. Fiberglass/resin plugs can be made up with no big problem and, tapped with a pipe tap, will serve as piping mounts for the inlet/outlet piping and valves. A bead of plumbers putty around the inside edges of the plugs and a tie-down furniture dolly type strap with turnbuckle will seal the things for you. The straps of course are secured to the all thread on both ends. The "upstream" end piping MUST include a tee and vertical stand pipe to allow for freeze expansion of the water. This stand pipe is sized to a level above the top of the tank, but not too far above it since it must not restrict the free expansion of the ice.

Insulate this pipe too. If you use this system, I would disconnect the fill pipe from the tank whenever really cold weather is coming. This allows an extra expansion point for the ice and will prevent any runoff water from freezing into the fill pipe and screwing the pooch. That sure would be the safest way at any rate. A thousand gallons of water can make a mess at any time, but when it cascades down from a few feet of elevation you can easily see that you get a multiplying effect in it's actions.

Also, sewer pipe is usually not designed to be water tight. That is, there are usually not any provisions made for sealing the sections. The "sanitary seal" function is served by the way that two or more sections are joined together. This is accomplished by widening the mouth of the inflow section so that the outflow end of the joining section will be "seamless" in the inside of the pipe where they join together. That leaves a lot less area exposed for snags or catch points for the effluent flow. And, finally, the pipe is normally used in a slightly inclined manner, nominally 1/4 inch of drop per foot of horizontal run, so there is no reason to make a perfect seal for it since gravity and flow dynamics will ensure that it empties.

That said, I, like you, can't think of any other good reasons why you can't use the damn thing as a drinking water cistern. You may well get some "leaching" effect from the lime in the cement, but I have personally seen upwards to 100 or so cement cisterns in various places around the world, and, IIRC, there is a lot of cement used in some of the aquaducts in a lot of places too. I rather doubt that there would be anything special about this particular piece of pipe. My guess.

As a side note, all of the cement cisterns that I have seen have been a minimum of 4" thick, most are 6". All were rectangular in shape. Your sewer pipe is probably 2" thick walled.

Old rule: When you double the thickness of any substance, wood, cement, steel, etc you QUADRUPLE the strength of it. You may have a fairly weak pipe there.

As for freezing:

The water in the pipe will react in the same manner as does water everywhere when it turns from a liquid to a solid. It will take the "path of least resistance" and push upwards against the top or lid. Until the thing becomes frozen solid that is. When the water freezes to the depth where the weight of the ice above overcomes the force exerted by the liquid water under the ice, that quantity of liquid water which is approaching the freeze point, the path of least resistance could then become your cement pipe wall. Such a thing should not happen in the real world, however, Murphy is alive and well, and Murphy's laws are y2k compliant.

Remember the milk bottles that we used as kids? I was raised in Ohio and I still remember getting to break off the "stick" of cream from the frozen milk bottles on the front porch in winter. The milk would freeze and the old style cardboard lids would be pushed up a good 2 - 3" above the bottle. I don't recall any broken bottles though.

The same thing with your tank/pipe. Give it room to expand and it should work out nifty neato for you. I personally wouldn't use a septic tank cover though. They are about 3" or so thick and pretty heavy. You can form up and pour a circlular cement cap about 1/4' - 1/2" thick and do the same job. Or, any auto body shop has fiberglass and resin that you can use to make a cover to fit. The forms can be any of the craft type light wood pieces, rattan etc. They can be bent to form a circle quite easily. Either way, you can install a handle, or lifter in the thing before it cures.

Perversely, by using it horizontally, you greatly increase the chances of freeze problems in the pipe depending on how good a job you do in sealing the end caps. If you do a real good job, and you then fill the pipe up, you will have a really big ice worm if an end cap fails, or a modern art form where the pipe broke apart if the end caps hold. Either way, the old 85% maximum fill level will save the day under MOST normal circumstances. A loose fit plug at the top with the flexibility of movement of the piping, and a pipe tee with a stand pipe on the upflow side of the tank will solve the problem of the tank freeze up. You at worst will simply have a really big popsicle.

As for the temperatures required to cause a freeze problem: To solid freeze a full 10 x 4 foot pipe would take quite a long spell of very cold temperatures. Several days I would think. That is continous temperatures of well below freezing. The cement will insulate the water to some degree, but since I don't have my handy dandy chart of R values of building materials in front of me, I would not hazard a quote. Gut feeling - 4 or 5 days of continuous temperatures of 20 - 25 degrees would be needed to bring the water temperature down to the freeze point and to begin the solid freeze operation. This is just a SWAG though.

Easy enough to insulate the outside of the pipe (tank) using hay bales, dirt, etc.

I assume that you intend to fill it from a catchment system, roof area, steel sheeting panel, plastic sheeting, etc.

That is an assumption on my part Sir.

You made mention of a cover for the thing so I assume that you mean to have a catchment feed line into it. The plumbing to the tank would simply be a piece of 3" pvc pipe threaded (or slip joined ) into a fiberglass/resin lid sized to fit your pipe. You then slip join a 45 degree angle 3" pvc pipe ell onto that pipe and then plumb to your catchment area outflow piping.

If it were mine to do I would use a short section of 3" pvc pipe to a 3" pipe tee then to a 3" pipe nipple then to a 4" flexible tubing, the thin wire wrapped clothes dryer exhaust type stuff, with two of the standard hose clamps to attach it at some convenient point. This will allow for some "wiggle room" in your plumbing and for sway, and for any maintenance required on the things. It, like all of the pvc piping, is very inexpensive. The up looking (open) of the tee is where you would install the vent stack pipe.

Also flexible 3 1/4" metal stove piping with the band aid (radiator) hose clamp on the upstream (High side) of the piping and the lower (tank) side end of the flexible pipe inserted into the pvc tank pipe will serve to fill the thing., it will do the same job and last longer.

Any diverter valve (gate) from your catchment area to the tank could be a simple piece of aluminum gutter flashing sized to fit your needs, or just unscrew one of the dryer (flex) hose clamps and let the flow run off. This all in turn assumes that you care about such matters. If your intent is just to fill the tank and let the overfill backup and spill off you don't need anything like a diverter gate.

I personally would use a ladies nylon stocking slipped over the downspout and the other end inserted into the flexible piping. The flex is then secured by the bandaid (radiator) hose clamp to the downspout, thus securing the nylon too. This gives you a cheap and really good inline filter which you can clean out very easily at any time by simply unscrewing the bandaid clamp and removing the nylon.

If you intend to go ahead with the vertical pipe and slab style tank pad as you first mentioned, your pad plumbing is simply laid in the same way as you do for a house on a slab and just use a bigger size pipe in the slab.

By way of illustration: a slab 6" thick on a 3" sand layer and reinforced by a 1/8" wire mesh over the pipe which is laid in a trench and bedded on the sides and bottom with straw or hay.

The plumbing that I personally would use would be a 3" pvc pipe 90 degree elled up and then nippled to a point 6" above where the tank slab surface will be. This will provide for any trash/dirt/sand/leaves, settlement in the tank.

So, you would have the pipe laid in a trench dug so as to have the surface of the pipe just below the surface elevation and extending out from the tank site for a distance of at least 2', and inclined at 1/4" drop per running foot of horizontal pipe.

An alternative to the trench would be to build up the pad site and have the pipe running on the surface and covered with hay, straw, dirt, etc.You then neck this pipe down to 1" using standard pvc reducer fittings, the fitting finally reducing down to the 1" size MUST be of a screwed (threaded) female outlet type. You then can install a 1" ball valve as a shut off valve for the outflow line by using a 1" x 2"L pvc nipple, the valve, and then a 1" screwed to slip joint fitting. Use TEFLON(R) tape on all pipe threads., or use plumbers pipe putty to seal the threads. Both are available where you buy the pvc pipe and fittings.You then simply continue to add pvc piping to wherever you are going with the water using 1" pvc piping.

This all asssumes, again, that you have the tank sited on a location that is above the level of the point that you intend to actually fill the buckets/sink/tub, whatever.

Your water pressure will be the "head" pressure of the tank minus the rise of the outlet where you actually draw the water out of the pipe. This "head" pressure will reduce as the the tank level drops of course, again at the rate of 0.43 psi per foot of level loss. Gravity will help give you the remaining water down to the 6" level, which you lose as a sacrifice to the cleanliness of the water. You could probably get away with 4" but I wouldn't go much lower. Sand will get into the tank and eventually cause wobbly woes for the system. You can install a water pressure guage in the downstream piping to give you a "guesstimate" of the amount of water in the tank. It would require that you install a pipe tee into the line and then a pipe nipple up to a pipe coupling fitting. The other (up) end of the coupling would then have a short pipe nipple to a shut off valve. The open (up) side of the valve would then go into another pipe nipple and then into another pipe coupling above that. Reduce the up end of the second coupling to the size of the guage fitting, and, using a bottom fitting guage with a range of say 0 - 30 psi, you are in business. This guage should of course be downstream of the shut off valve installed into the water line itself. This makes it easy to swap out the guage, or to plug off the guage fittings if need be.

The tank pad is the tricky part of the operation. If your intent is to set the pipe into the pad itself while the pad is still "wet", lots of luck. You will need several strong young Texans to help grunt the pipe into place for you, or Mr Archemedes and his lever. This is of course the best of all worlds.

You (they) all pick up the pipe and pissant it into position where you then brace it until the pad cures, 3 - 4 days, and then you are in business. Providing of course that your pipe doesn't just settle completely through the pad cement due to it's weight.

An 'A' frame with a block and tackle hoist would allow for the pipe to set at whatever level that you want it to be at. A couple of ropes, or furniture straps, tied off to the 'A' frame from the pipe will stop any wind sway until the pad cures. If you use an 'A' frame, be sure to use a three point tie off for the tank to keep it fairly level during the curing of the pad.

If your intent is to pour and set the pad and then place the pipe into position you will need a lot of plumbers putty to use as a seal for the tank bottom where it rests on the pad. The tank weight will press into the putty enough to greatly slow the leakage from the tank. An additional bead of Silicone weather stripping sealant around the outside of the tank should do the job. For what it's worth, I personally would use the "bell" (wide) end of the pipe as the bottom.

As far as moving the monster into a close position to your site.

Using 4 2"x6"s x 8'L, 2 4"x4" x8' long, and 4 2"x6" wedge cut chocks will allow you to use Mr. Archemedes and his lever thingy to roll that hoss into the exact position where you want it. You can site that sucker to within an inch or so of the desired location by just using a little thought and very little sweat.

Lay down the 2x6s end to end, two at each end of the pipe in the direction that you want to move the pipe. On the upside you place the 4x4 about 3" out from the side of the pipe and then use the other 4x4 as a lever, in the center of the pipe, to roll the pipe up onto the 2x6s. Use the wedges to align the pipe, and then you can roll the thing wherever you want it by guiding it with the wedges spaced at either end that you want to turn or align, and moving the 2x6s as required to provide tracks for the pipe to roll on. The 4x4 layed as a crossmember on the upside of the 2x6s will allow you to get a good leverage point to roll the hog without breaking a sweat.

If it were I who were doing it, I would locate the pipe to where I wanted it first and have it laying on two furniture straps located at about 1' from the "top" end, which, again, by the way, would be the small (outlet) end as the top end, to lessen the trapping of dust, bugs etc.

Erect an 'A' frame with a block and tackle hoist over the pipe, here you need about 12' of height clearance, and tie off the furniture straps to the hoist. Raise the pipe up to clear the ground and then secure the thing with at least three (3) straps.

Do the site preparation work, forming and pouring of the slab, and then slowly lower the pipe down to the desired depth into the pad. Let it cure for about 4 days, wetting it down as required, and you should be in business.

Oh, in case you are thinking of filling this thing from a well instead of the catchment:

Be absolutely certain that you provide a block and drain valve in the upstream side of the system and that you drain the lines when really cold weather gets in. I would run the fill pipe along the ground from the pump to a point just short of the tank. Where the pipe will start up it's vertical run to the tank you install a pipe tee instead of an ell. The open end of the tee is where you install a short pipe nipple and then a shut off valve. This will be your drain valve which will drain all of the lines from your pump and from the rise to the top of the tank too. You then simply run your piping up to the top of the tank and into the top cover. Insulate the piping with the foam rubber insulation (you can find it just about anywhere but every plumber or builer supply store sells it) and you are off and running.

I would also put in a "full union" fittting in the piping at both the lower and the top parts of the fill piping. This will make any future maintenance work on the pipes very easy to do. A full union fitting allows you to unscrew the pipe at that point without twisting or turning the pipe itself. I would also use 1" pipe for the fill side of the operation.

I hope that this will help you somewhat with your pipe Sir.

Sorry for the verbosity, but some things need to be explained in detail, especially with the newbies who may also try such things too.

Let me know if I can be of any further assistance to you. I hope that I haven't muddied the waters too much, if there is something unclear about this holler back and I'll try to clarify it. I realize that I don't know how to express myself as well as you do, and therefore this may be somewhat obscure.


-- sweetolebob (buffgun@hotmail.com), March 26, 1999.

Gentlemen, Some caution is absolutely necessary in erection of such storage chambers. Once, as a plebe at Academy of Desert Engineering, I was charged with erection of just such a device; 13 foot tall sewer pipe to be converted to water storage.

Upon careful erection upon a most sturdy base, I was dusting off my paws and beginning to admire my handywork when it became apparent that the massive structure was wobbling ever so slightly. As the magnitude of wobble increased, so did my concern for my personal safety.

I began to ponder an escape avenue, but my intuitive calculations of probable landing sites was complication by the wobble effect. Being a plebe, I had not yet had higher calculus or physics and I was unable to deal with this variable.) To make a long story short, my intended escape route became circular, a calculation I now regret.

Fortunately, the concrete tube shattered about two seconds after impact, but not before compressing the vertical measurement of the center of my body to a width of approximately 2.76 inches. Ironically, my legs were unaffected, so I was able to walk in a ducklike fashion.

This situation persisted until my recuperative powers and a 60 second commercial break restored me to full height. Best of luck in your endeavors.

-- Wiley C. Coyote (wile@wilewest.com), March 26, 1999.

Robert Cook & S.O.B.,

Thank you both for the considerable effort and sharing of knowledge and expertise obvious in your answers and the time it must have taken you. I genuinely appreciate both.


Thank you as well, and as to your suggestion to cut the pipe in half; it offers a number of advantages, but the primary purpose of upending the pipe is to achieve the pressure to assist gravity flow. Also, doubling the number of fittings and connections has to double the chances of problems and eventually increase maintenance. I'm trying to "build for the ages", so to speak.

At this point, all the issues that I see are covered between S.O.B.'s and Robert's answers, except one. That is the possibility S.O.B. raised that the pipe may not be capable of dealing with the pressure at the bottom of an upended tank usage.

It occurs to me that I might be able to eliminate this possibility and prevent seepage or leakage at the bottom in the following way:

Begin with a septic tank cover as a foundation slab, on a bed of gravel and sand. Bring the plumbing through the "clean out" plug in the center. Set the pipe on the slab, centered over the plumbing and build a circular form around the base so that a "collar" of concrete may be poured, sealing the bottom and adding additional strength where the pressure is greatest. If the form were in place and say, 3 inches of wet concrete poured into it, setting the pipe onto the slab should seal the bottom, no? It has always been my intention to build a "base" of rock and earth pushed up against the tank, to a height of about 4 feet, for physical stability.

This raises four issues (that I can think of right now) about the method.

First, would such a collar add enough strength to do the job? As is apparent, going to all the effort to build this thing would only increase the agony should it come apart the first time (or any other, for that matter) it was filled!

Second, is it feasible? That is, will the concrete in the "collar" bond well enough to the concrete of the slab and the pipe to create a mechanically solid and leakproof construction? (as you can see, I am largely ignorant about concrete)

Third, assuming that this is a viable way to proceed, how high up the pipe should I go with the "collar"? I can figure the pressure at each point, but what I am asking is where is it safe to assume that the pipe doesn't need any help?

Last, but perhaps most important, is there some way that I can find out what the characteristics of the pipe are to begin with? If it should be that the pipe is strong enough to start with, some of the questions about the "collar" would be moot.

Wiley C. Coyote,

LOL! I'll be EXTREMELY careful! (and I won't be buying anything from "Acme" either!)

-- Hardliner (searcher@internet.com), March 29, 1999.

Hardline, One further consideration. I wonder if your daily/weekly usage rate will be high enough to prevent stagnation. If you've got plenty of power for pumping and plenty of water in the ground, you can always flush it at will. Otherwise, there might be some optimum storage rate that will also minimize stagnation concerns without chemical additives.

Finally, as a layman, if I were to walk up on your project in construction, I'd expect to see some vertical rebar in there somewhere. Don't ask me where. I'd also expect to see some horizontal steel in the base.

-- Puddintame (dit@dot.com), March 29, 1999.

Ah - the joys of uncertainity and exploration - I'm thinking that the pressure (psi) at the bottom is (max) of 13 ft x .43 psi/ft or 5.6 psig. Thus, although the total weight of water present is high (as you would expect) the actual pressure (force per area of the water on the concrete wall) is very low compared to either the compressive strength (high) or tensile strength (lower) of reinf. concrete.

-- Robert A Cook, PE (Kennesaw, GA) (cook.r@csaatl.com), March 29, 1999.



It occurs to me that a quick phone call to your local cement company ( Cement R Us ?), or builders supply house would get you the answers to several of your questions from the folks who make the things. Someone near by to you makes the culverts, cement steps, septic tanks, etc.

By this I mean:

1. Sewer (drainage) culverts, (I think that is their technical title), are pretty much a standard item everywhere in any given area. Most of the specifications are set by city/county laws, at least here they sure are.

2. The things are relatively inexpensive and as such aren't shipped very far away from the point of manufacture.

3. This then tends to indicate to me that some company pretty close to you made the thing. But even if not, they are, after all, a fairly standard item, so information on the care and feeding of it should be readily available from the local guys who do it for a living.

Have you finger walked the local area Yellow pages? The information should be free too.

While you are asking, ask about the load bearing capabilities of that septic tank cover too. You are putting some pretty hefty "ground loading" on that thing with this, and I bet that it isn't reenforced with rebar or wire mesh at that. Those covers weren't meant to load bear a whole lot of weight either, since you normally just bury the thing a few inches down at best, and that only for esthetics, plus that weight is in turn transferred to the side walls of the septic tank itself.

You made mention of 40" exterior width pipe. I am assuming that this refers to the inlet (wide, or bell) end. If so then you have a 2" walled pipe. If not and you refer to the small end, or if both are of equal diameter then you have 4" walls.

Be sure that you are all singing from the same song book when you discuss it with the cement dudes.

That being said, it has been my experience in life that water will go everywhere that you really don't want it to go. Generally wherever it will cause the most grief to you.

I will absolutely guarantee you that you will have some seepage (small leaks) from the joining of the cured to uncured cement pad, if for no other reason than from the principle known as "wicking". That's the same way that the oil gets up to the tip of the wick in a lantern.

You can greatly slow it down, but it will eventually seep through the join of the two "pours". You can decrease it to a bare minimum by "roughing" up the entire surface of the septic tank cover and of the pipe itself up to the height where you intend to pour your new cement and before you set the pipe.

Roughing means scouring or lightly scratching the surfaces of the things before you pour the new cement. If you think about it, a scratch mark is just a very small valley or groove in a surface. By definition there must be two sides to this valley, so you have added a lot of extra surface area to the thing which will be used as a "purchase" or "binding" area by the new cement.

You may get really lucky and escape this seepage for 3 - 4 years, or even longer, or you may get some from day one of usage. But you will get some. The exterior surface of the pipe should already be of a rough type mix since nobody ever cares what those things looks like, but I would rough it up some more just for safety.

Above all else, make absolutely certain that the surface of the septic tank cover isn't smooth finished, (machine troweled), at any point on the surface where the pipe will contact it or where your plumbing enters the pipe. Machine finished cement is very hard and smooth and there is absolutely no way that the new cement will even attempt to bond to it. The rougher the better.

Think of it as being "broom swept". You want the surface of the pad to look like you swept the cement with a broom while it was still setting up, or jelling.

If you end up using the septic tank cover as a base, I would think that you would need to pour a pad of about 80" in diameter as a minimum, and I'm not real sure that I would use a circle form. This is to allow 20" in any direction from the outer edge of any part of the pipe wall.

It is fairly simple to form up a square form, and it is just as stable a platform for the pipe. That 80" just allows 50% of the diameter of the pipe (one pipe radius) out in any arc from the pipe for stability since you will not have a true solid base, but rather one which consists of two (2) separate parts to a total of 6" in depth.

This is the premise that you will never have a true bond between the septic tank cover and the new pad. And, obviously, you have an imperfect bond of the tank to the new pad, since the pipe exists now and the new pad is yet to be.

Also, as Puddintame has mentioned, don't forget the rebar or reenforcing wire mesh in the new pad when you pour it. You need it to spread out the tank's weight over a much larger area of the pad.

I assume that your intent is to pour the pad, to include the plumbing inlet hole, at one time and then set the tank (pipe) while the pad is wet. If so, remember to work the cement (it's called *finishing* the cement) around the plumbing area really well since these are additional leak points and you won't be able to get to them once the pipe is set.

Failing that assumption, just how do you intend to seal off the plumbing entrance?

Is there a Civil Engineer around here who can help out with this?

Remember that I am just an ex-instrument technician, and over the hill gunner, and I know that I have lost at least half of my reasoning powers with the two surgeries, so please verify anything that I post. I'm not as well versed as I used to be and I want to be sure that we get good information here.

If not here, you can certainly get some good advise from the cement company. They work with this stuff every day.

Just be sure that they understand what you are doing with the pipe.

Since you aren't pouring a slab for a house, which would have a "footing", or chain wall around it, you can't use the usual anchor bolts here. You could, but working on two (2) 3 inch thick surfaces you would end up doing more harm than good I think.

I hope that I helped somewhat. Ask any further questions that you may have, and I'll try to dig up the answers for you.

Let us all know what you find out in your local area search.


-- sweetolebob (buffgun@hotmail.com), March 29, 1999.

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