Frequently Asked Questions
Water Storage Tanks
Q: What is water storage?
Storage tanks are many and vary in size and construction from small plastic tanks to concrete and steel above ground tanks and can vary between 50 litres capacity to a million litres of more.
For most purposes, storage tanks would usually be in the 1 to 5 tonne range, constructed of bonded nylon and may be placed above ground, preferably under cover or shielded from frost. Such tanks are lightweight, easy to move and maneuver and last very many years - maintenance free and resist harmful solar UV radiation.
Q: What type of storage do I need?
For most scenarios we always recommend a water storage tank. This tank or series of tanks may be sited above ground under cover - in an out-building or other enclosure for example or may be sited in the ground in a purpose built chamber. Tanks above ground which are not under cover will either need to be shielded from frost - or built of a special type which resist frost. Although it would be very difficult to freeze such a large volume of water.
Tank size is calculated as a portion of your water requirements.
For example: if you need two tonnes a day and your system suddenly develops a problem, you either have to do without water until the system has been repaired or you must switch back to mains water - if you have mains. A two tonne tank means you can continue using your water and have a day in which to isolate and fix the problem.
Suddenly finding yourself without water may be inconvenient if the water is simply for a home situation but if your pumping water for commercial use, this could be costly to your business. Having a storage tank which can store a portion of your water gives you time. You can continue operating as you effectively have a reserve.A storage tank buys you time to get any problem fixed, enables you to continue using your water, reduces stress on your borehole or well pump by not having it operating constantly and in general gives your better control over your entire system. Thats not to mention the fact the pump is not on all the time you are saving money on electricity.
Q: What is a bunded tank and do I need one?
A plastic tank within a tank. This design was created to provide a safer means of storing flammable fuels and is not specifically intended for storing water.
Q: Do i need to place my tank above or below ground?
This is really a question of personal preference. If your tank is sited in an area where you do not want to see it or if available land space is limited, it might be better to put it below ground. You can use the same type of tank as you use above ground, a simple bonded nylon tank, though you would need to construct a chamber to house it because nylon tanks cannot resist the pressure of earth or other material against them.
If however your tank is to be sited above ground, then this of course is not an issue. Placing your tank above ground has two advantages. One, there is no need to invest in the cost of having an underground pit excavated and then a concrete chamber built in it and two, having the tank above ground and raised means you can have a tap fitted to the tank near the base to draw off water without the need for pumping. If you don't want to see it, then you can simply add some screens around it to disguise it.
There is some plastic tanks which are new out that can be buried directly without the need for a chamber. They have specifically designed supports and can withstand a fair amount of hydro static pressure but they do require strapping down which may require a concrete base. We have installed many of these now and have had zero problems with them.
All you see at ground level is a standard man hole cover so they are very effective in a garden.
Q: What about concrete or steel water tanks?
Concrete is a good medium from which to construct a water tank however they are expensive. If you're keen on DIY and reasonably fit, you can build one yourself. Concrete water tanks should be lined for two reasons.
One -if you intend to use the tank to store drinking water, you should apply a generous layer of a special sealer to prevent any leaching from the concrete into your water
Two - to prevent the concrete from absorbing any water - as this may cause the concrete to crack and split if you expect sub-zero temperatures. Frost heaving.
Steel is commonly used for storing very high volumes of water but are mainly for commercial and industrial.
Nylon tanks can be built in sizes up to 20,000 litres though few manufacturers of such sizes exist within the UK as the cost of molding them is very high and customers are few in number. We have however installed a number of them and they do make it a great option if you need to move the tank at some point in the life of it.
In reality, once we get over 20,000 litre sizes, tanks tend to be built of steel. They can be tall and narrow, wide and short, be unlined for irrigation or grey water systems or may be lined to store drinking water. Such water tanks are usually made to order. Typically they would be built to contain water volumes ranging from 10,000 to a million litres.
If your project is likely to need very high capacity storage tanks, we will help you make the right choice at the appropriate time.
Q: Do i need to protect my water storage tanks from frost?
Yes and no, This can be done easily and cheaply. Plastic tanks of special construction may be purchased which resist frost though they tend to be rather more expensive than conventional plastic water tanks. Sighting your tank under trees, in an outhouse or barn will usually suffice and prevent freezing problems. The construction of a simple roofed structure will often reduce the risk of freezing too, insulation in the roof area to create sufficient 'indoor' effect - as to keep frost out.
However we will also argue that yes there is a risk of freezing, if you do not cover it we have found that the top inch of water will freeze if the water is not used for a day or so but if you are constantly using the water it simply will not freeze because of two reasons. The first being the volume is just to big to completely freeze within a few days. The second is that water below the ground from a well or borehole is usually +12 degrees all year round.
If using a plastic tank it is able to expand and contract so there is also no problem with the frost.