CISTERN BASICS
Water is a leading prep for survivalists, preppers, and virtually anybody looking to prepare for an emergency. For the most part water prepping consists of stockpiling hundreds or thousands of gallons of water, well installation, constructing reservoirs, and/or the use of equipment to reconstitute waste water. These are great preparations and if done correctly you may have no need of any other type of water-prepping, however there exists other ways to prep water, cistern collection. The most effective way to collect water outside of having your own well is through a cistern system, connected to the downspouts of your rain gutters. This method uses zero electricity to collect the water and store it. When precipitation falls on your home it runs into the gutters and eventually the street, sewer system, and eventually the rivers. You get absolutely zero use out of these possibly tens of thousands of gallons each year, besides washing the bird droppings from the roof of your home. Why not utilize cistern tanks to capture some of that water to use at a later date? Collect today so you can have water tomorrow.
Why a Cistern and not another Water Prep
The last thing I would do is discourage anybody from prepping any method of water collection, however cisterns have certain tangibles other types may not. See the examples below;
Water Wells: Private Water Wells may not be permissible by your local municipality, however I have yet to find a single municipal that does not allow surface cisterns.
Water Wells: Drilling or Digging private water wells can be extremely expensive and time-consuming. To make matters worse the quality of the well you might find yourself with is reliant upon many variables, the least being the workmanship of
the company you hire.
the company you hire.
Reconstitution: Reconstituting grey water back into drinking is a great way of extending existing resources, however when you reconstitute you still have some water loss in the form of black water or sludge. If you do not replenish your stores they
will eventually run out.
will eventually run out.
Reservoir Construction: The ability to construct a reservoir is dependent upon running water from runoff, rain, creek, river, or natural spring. If you got the water flow and the land that is great, but most people live in the suburban and urban settings.
Stockpiling: Stockpiling is a great way to prep water, especially if you know exactly what you need. The biggest problem with stockpiling is the storability of the water, because gallon jugs or drums need an enormous space for storage. Another issue is that most containers purchased for stockpiling water must be environmentally controlled, therefore they are unable to handle freezing temperatures if stored externally.
Conclusion: All methods of water collection are good ways to prep. As well as all methods may not be suitable to your purposes or needs, so you must find the right one for your situation. It is has been my experience that using diverse methods to prep water is a good thing, because no matter how seemingly full-proof a system might be, water supply disruption can happen.
Cisterns in History
The Romans were not the first people to use cisterns but they did so in such capacity it is worthy of noting. The cistern of Piscina Mirabilis for example, located in Italy measures over 12,500 cubic meters, or 441,433 cubic feet of capacity, or over 3.3 million gallons of water.
Piscina Mirabilis was designed to supply the Roman Imperial Fleet with fresh drinking water and fed directly from the main roman aqueduct, Aqua Augusta. This massive cistern was dug entirely into the cliff face, with massive pillars and vaulted ceilings. A storage tank at a municipal water system I used to work at held 1 million gallons of water and I remember thinking at the time that it looked massive, the city supply would have been dwarfed by Piscina Mirabilis.
Cisterns of Today
Today most cisterns are much smaller and prefabricated from steel or plastic materials, but the basic idea is still the same with few differences. Instead of transferring water runoff from distant mountains or reservoirs we utilize our own aqueduct type system we call gutters, downspouts, and storm water drains. The water transfer may be “slightly” different but the purpose is still the same; you take water that would not normally be used for anything, transfer it to a storage facility, and use it later.
TYPES OF CISTERNS
There are three basic types of modern cistern collectors; (a) subsurface holding tanks, (b) surface holding tanks, and (c)
emergency and alternative storage devices. Each system have their own pros and cons, but you could hardly go wrong with using different types. I have identified some pros and cons of each type below to aid you in your choice. Be aware that I have absolutely no idea of the city code you live in or your household situation.
emergency and alternative storage devices. Each system have their own pros and cons, but you could hardly go wrong with using different types. I have identified some pros and cons of each type below to aid you in your choice. Be aware that I have absolutely no idea of the city code you live in or your household situation.
Surface Cisterns
PROS
I. Water is easily obtained without pumps, or much effort.
II. The higher the tank is placed above the ground the more readily available water pressure. It will not be high water pressure but you will not have to bucket it if the spigot is placed towards the bottom.
III. If the tank is left in direct sunlight and painted black it could, (depending upon the volume of water) heat the water for an added benefit during colder seasons.
IV. Surface tanks like subsurface come in a variety of sizes.
V. It is not commonly required to have city or district permission for medium and smaller holding tanks.
CONS
I. Water becomes more vulnerable to stagnation, algae growth, and human intrusion.
II. Surface tanks are prone to freezing in seasonal climates.
III. Surface tanks are prone to settling over time, usually on one side.
IV. If left uncovered surface tanks can become a haven for mosquitoes, flies, and disease.
Subsurface Cistern
PROS
I. Tanks below ground retain geothermal benefits as the hotter external air during the summer can not reach the water and warm it. In other words the soil compacted around your tank insulates it very well from solar and air temperatures.
II. Tanks below ground are better insulated from freeze, but before you place your tank you need to know the depth of your frost line. Plan to bury your tank several inches below the frost line or have built a fitted and insulated cover for the top.
CONS
I. Pumps, Buckets, or Siphons are required to lift water from under ground.
Emergency and Alternative Storage Devices
PROS
I. Emergency Storage Devices can be kept out of sight and mind, not being deployed until needed.
II. Emergency Storage Devices can be added to existing cistern system during an emergency for extra capacity or to replace broken or damaged tanks.
CONS
I. If only cistern system is an Emergency Device the prepper risks having little to no water when they need it most.
II. Water weighs 8.34 lbs per gallon, multiply that times the device capacity and you have a significant amount of weight. If the prepper fails to add support under the device before installing they risk tipping of cistern or damage to foundation of nearby structures.
A little bit more about Emergency Devices
These devices are not filled until the moment they are needed. I do not recommend waiting until an emergency effects your household to collect water, but it may become necessary to do so when the time comes. I have listed a couple of common types of emergency water storage devices;
Above Ground Swimming Pools: There are numerous soft-sided swimming pools that are perfect for storing water, even at the last minute, and I keep one on hand. Above ground pools range in the 1500 gallon, all the way up to 15000 and higher. The one I chose is made of strong PVC, and holds 1800 gallons. It cost me $75.00 brand new (the same cost as a Food Grade 55 Gallon Drum), and it came with a pump. I added several dozen filters, extra bleach for disinfection, and a plastic cover to the list. It takes several hours to fill with a regular 5/8 garden hose, but if I have the time than I will do so because 1800 gallons is better than nothing. If the emergency occurs near or during a rainy season I might even place the pool near my existing downspouts, and when the cisterns full I can always run another 1800 gallons into the pool. In case your doing the math this adds almost 5 gallons of water, per day for an entire year.
Existing Swimming Pools or Hot Tubs: Caution: FEMA does not advise that people drink the water from these sources either, however many devices exist that can remove chemicals from the water thus providing you with filtered water. Hot tubs can hold several hundred gallons of water, and pools upwards of several thousand. It would be ridiculous not to plan to use these devices as resources when the need arrives, however you must have filtration systems to remove these dangerous chemicals. Also note that occasionally, despite harsh chemical treatment these areas can become breading grounds for bacteria, viruses, insects, and parasites. Removing the chemicals may still not make the water safe for consumption, as always add another level of water treatment such as distilling.