D&D 5E Decanter of Endless Water facts


Rotten DM
So Hussar mention no fresh water in the big WD. Here is an article I wrote/updated years ago.

Decanter of endless water.

Ok let see the time to fill various things with the decanter.

For an oval swimming pool the calculation is Len * width * avg depth * 5.9 to find the number gallons an oval pool holds. For a rectangle swimming pool the calculation is Len * width * avg depth * 7.5 to find the number of gallons a rectangle pool holds. I got the calculation from a swimming pool site.

A 16 by 32 foot pool with an 8.5 deep end and 3 shallow end, holds about 22,080 gals so my parents’ pool holds a lot. The decanter has the rate of 30 gallons per round = 300 a minute = 18,000 an hour = 432,000 gallons a day, and 157,680,000 gallons a year. Then it would take 1.226 hours or 74 minutes to fill the pool at my parents’ house. Dad will be happy.

For 10 by 10 by 10 room it would take 25 minutes to fill. The orc will have time to eat his pie and brush his teeth before he starts to get worried. For a 20 by 20 by 20 room it would take 3.33 hours (3 hours 20 minutes) or just enough to enjoy one of Lord of Rings before you drown.

If want to fill the Empire State building 424 * 424 * 1250 * 7.5 (this max volume not true) 3901 + days. 10 years 251 days (I could not find where the dimensions of the breaks were)

Looking at the sample dungeon in 1e and 3e DMG and fill it to depth of one foot. The sample dungeon is 577.5 squares making 5775 * 5775 * 7.5 * 1 foot deep = 250,129,687.5 gallons or 579 days. This does not take in account the depth of the various stair ways and if the water was able to enter all parts of dungeon.

My house is 1300 square feet. So 1300 * 10 (I don’t have ten foot ceilings) * 7.5 = 97,500 gal it will take 5.4166 hours or 5 hours and 25 minutes. So if I late going home for lunch my house would be over flowing from the two chimneys. Hope the cats remember to hold their breath.

The old joke about Englishman, Scotsman and Irishman with a wall around England. England is 93,000 square miles. 93,000 * 5280 * 100 (foot wall) * 7.5 (water) = 368,280,000,000 gallons = 2,335 years 225 days. So if the decanter of endless water starting filling England on the stroke of midnight in the year 2000 you would have to the year 4334 November 24. 11/24/4334.

The Earth’s total surface area is 197,000,000 square miles. 197,000,000 * 5280 * 7.5 would result in 7,801,200,000,000 gallons. 49,474 years, 323 days and 8 hours.

How much water would give to town’s people besiege? A person needs one liter of water a day to replace water loss by normal activities but needs 2.5 quarts to maintain health but this includes water contain in food.(American Water Works Association 25 facts about water). It was hard to find an exact minimum of water usage per day which did not include modern appliances. I am going to go with one gallon to include bathing, cooking, or activities. So one decanter could supply the needs of any fort. If you use the one hundred gallons of water per person per day (this include modern showers, dishwasher, and washer) a larger village can live a modern life if the population is under five thousand and the orcs are at the gates. So the only major problems would be spellcasters dispelling the decanter, weather in the winter freezing the bottle up, and vandals.

A fire engine can put out up one thousand gallons of water a minute on the water cannon. To get down three hundred gallons a minute you have to go to the “Neptune” 1837 fire engine in Toledo Ohio museum.

Decanter of Endless Water: If the stopper is removed from this ordinary-looking flask and a command word spoken, an amount of fresh or salt water pours out. Separate command words determine the type as well as the volume and velocity.

“Stream” pours out 1 gallon per round.

“Fountain” produces a 5-foot-long stream at 5 gallons per round.

“Geyser” produces a 20-foot-long, 1-foot-wide stream at 30 gallons per round.

The geyser effect causes considerable back pressure, requiring the holder to make a DC 12 Strength check to avoid being knocked down. The force of the geyser deals 1d4 points of damage but can only affect one target per round. The command word must be spoken to stop it.

Oh goody. New stuff from the army.

The 3,000-gallon onion tank is a highly mobile, easily transportable, manually inflatable, collapsible fabric water tank. The tank is 23 by 28 by 42 inches and weighs 130 pounds packaged. The tank is 56 by 148 by 94 inches and weighs 24,020 pounds filled with water (Figure D-1). From fm 10-52-1 appendix d.

You got your water for the day for 3,000. Call it 30 minutes setup time. Fill time is 10 minutes on geyser. A five man team can rig a support beam so two or more men can hold the geyser. But this a little too big.

In the field mess we had a few collapsible fabric drums which carried 55 gallons when full iirc

It was basically 3 six foot long poles, a metal plate with holes for the poles and chain in center. A od green canvas bag with a dust cover and one metal rim with 3 chains connecting to the center. And the center was clipped into chain above. It took 3 minutes to setup well more if did by the regs digging footing holes for the posts, and laying down peddles to keep the mud down. Call it 10 pds when empty. Fill time is about 6 minutes on stream. Under 2 on fountain. Call it 10 minutes total setup time. Break down time is less especially if empty.

FM 10-52 Chptr 2 Water Support Planning and Operations

Speaking of bathing you don’t shower but bathe in your pot helmet or a bucket. So call it a gallon of water each of bathing and you don’t have to bathe each night. But if you need a shower canvas bag with shower head. Call it six poles each 8 feet long. 3 for shower head, 3 for curtain.

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The big question is; how many decanters have been created? How many have been left open and filling the world? Are the water elemental gods upset by them loosing water? Have the fire elemental gods created any?

Awesome! And, for some further context-

A 16 by 32 foot pool with an 8.5 deep end and 3 shallow end, holds about 22,080 gals so my parents’ pool holds a lot. The decanter has the rate of 30 gallons per round = 300 a minute = 18,000 an hour = 432,000 gallons a day, and 157,680,000 gallons a year. Then it would take 1.226 hours or 74 minutes to fill the pool at my parents’ house. Dad will be happy.
Water truck services to rapidly fill pools take 1-4 hours, depending on the size of the pool. So, a reasonable mental image could be a tanker truck full of water an hour.

Average minimum household water supply is 5 gallons / minute. More than 10 gal/min and you may need a second tank to draw from so the water doesn't jet out of the faucet.

I went with a gallon a day for the "travelling adventurer" water needs as well.

You pull the stopper on the decanter, and a few moments later you hear a wavering voice:

"Water is composed of two parts hydrogen, and one part oxygen."

A few moments later, the mysterious voice again can be heard. This time it says:

"When water is cooled below it's freezing point, it typically changes state into a solid known as ice."

Again, the voice is silent for a few moments. Until again, it speaks:

"Although we often simply call it 'ice' there are at least 300 distinct and different forms of solid water."

It dawns on you that you really have discovered the long-lost Decanter of Endless Water Facts.

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