New PROPANE TANK 4 Water Storage ???? - Welding progect

[OldMcDonald]

JT, Your logic is convincing, so I will not argue about the effect or otherwise of corrugations. Either way, 1000gallons cannot be collected off a 1000sq ft shed unless 1000gallons plus blow off and bounce off falls on that roof. Calculating what can be collected is not an exact science, and I always allow for some losses.

Different tanks for say the bathroom and kitchen need to be sized to make best use of the long term rainfall, and I found a lot of places in Australia had estimated that they would use far more water in the kitchen than they actually did, whereas bathroom tanks overflowed regularly - then ran dry.

 

[Jim Timber]

Your numbers for how much is collected is pretty darn close by my cursory examination of the math. You'll have losses from surface tension and evaporation as well, and possibly even failure to transfer depending on the mechanics of the plumbing, so getting it right down to the ounce (or ml) isn't going to happen.

It's interesting that people would think a kitchen would use more than a bathroom. 3 people flushing 2-4x a day, and then 40 gallons per shower is far more water than washing dishes or cooking would ever consume.

When our well at the cabin gets skunky, we use bottled water for cooking. A gallon lasts a family of 5 adults several days if we're not drinking it too. Even drinking it, we're still only going to chug down a gallon a person per day at most, and that's insignificant to a single shower.

 

[LD1]

The math sounds right but it doesn't work in real life. All I know is that when my rain gauge showed "about" 1/4", I could usually count on the tank being full again. I don't use a micrometer to measure the rainfall. Whether it rained at a rate of 1" per hour for 15 minutes or rained all night for a total of 1/4" It didn't seem to matter. I also know that if you leave a pan out in the rain and it rains 1/4" by the rain gauge, the pan will have more than a 1/4" of water in it. Can't explain it but it will. Perhaps it's the way rain gauges are calibrated or the fact that it can be raining here at the house and be bone dry down the driveway. All I care about is what I get in the tank.

The barn I'm collecting rain water from is 32x30 with a 2 in 16 pitch on corrugated steel roof. So do you increase the surface area for corrugated steel? I don't know. I have rain gutters that dump the water into 4" drain pipes under ground. The tank is under ground and I have the inlet/outlet reversed since one is lower than the other. I have the high end (tank inlet) connected to drain pipe with a drain cap and it functions as an overflow release at ground level.

Oh, and there's about six feet of extra roof on one side for the entire length (32') That side has an entrance door, chicken run and chicken coop under it.

Added this post since the EDIT sucks big time.

Corrugations dont matter, and neither does the fact that the building roof is sloped (so actually more sq ft than the building). You have to look at a FLAT plane, how much area is the roof COVERING.

30x32 with an extra 6'....so 36x32 is 1152 sq ft.

1152x144 makes it 165,888 sq inches

165,888 / 231cu in to a gallon = 718 gallons would fall on the roof PER inch of rain.

1/4" would only be ~180 gal
You need 1-1/2" to fill 1000 IF you could collect 100%.

For several reasons I will go with the steel tank.
Original steel tank lasted about 18 years. No problem with rust in water.

Was hoping someone had drilled or cut 1 up. Mainly want to know how thick the metal is.

Thanks to all for your replies.
Jim

I was scanning through and thought maybe I missed it.....Did you say what you are using the tank for?

Most tanks have the shell and end thickness listed on the placard.

My 500 gallon tank at my last place was was 0.195" ends and 0.248" shell

Dad has an older used one. Its 0.210 and 0.295 IIRC. The ends are usually thinner, cause they are domed so inherently stronger