Off Grid Water in Spain: Everything You Need To Know
You need a source of water if you live off-grid anywhere in the world. At a minimum you need water for drinking, washing, cleaning and preparing food. In a warm country like Spain, if you are planning on doing any gardening at any scale, you will need to irrigate your plants - often all year round.
How much water do you think you use per day in your household and how much could you get away with and still be comfortable? The Spanish average is 127 litres per day, and I think you'd struggle to get much below 100 without making major lifestyle changes (which maybe we should all be making - that's a different matter!)
If you are buying a property, having an idea how you will meet your water needs before you buy is paramount.
In this article I will explain some of the options you have for obtaining water in an off-grid setting in Spain. If you find this information useful and have the means, it would mean a lot if you felt like buying us a little Coffee or supporting us on Patreon.
Rainwater Harvesting from Rooves etc.
It is possible to live off rainwater harvesting, even in a country like Spain, if you have a big enough surface area and big enough storage facilities to get you through the potentially 9-month dry period. I know many people who do it - but it comes with its disadvantages.
You have to bear in mind that rain is increasingly falling in bigger, less frequent rain events. This is a challenge for rainwater harvesting because rather than having smaller storage containers that are regularly topped up throughout the year, you need to collect vast amounts of water in the few times it really rains hard, and keep that water on hand for a long time. You need to realistically think how much water you need to store to get you through 6-9 months without meaningful rain. Then you need to calculate the surface are you have available for caputring that water from, and in what kind of containers you are going to store it. The infrastructure is not insignificant .
You will likely chose to bring your drinking water to your house separately from local fountains.
You also might sometimes run out of harvested rainwater and have to fill up your containers by transporting water from a nearby fountain or source of agricultural water. This can be time-consuming and anxiety-producing, You wouldn't want to be doing this for water you intend to use on the garden. It would simply be too much work. You can probably transport a maximum of 1000l at a time if you have a van in which you can put an IBC, or a trailer. I use 1000l on the garden every day in summer. Are you going to cart 1000l back to your house every day in a trailer?
As you can imagine, growing food in Spain using rainwater harvesting only is very challenging. Although certain things can be grown, and there are plenty of dryland trees which can manage without irrigation, don't be under any illusions that you'll be able to have the veggie garden of your dreams. You will have to be very adaptive.
Traditional Rainwater Harvesting
In the above section, I'm talking about harvesting water from rooves of houses and other buildings or built surfaces. However, traditionally many properties would have harvested water from the land itself.
This is a possibility when the land sits on a hillside or terraces and there is a large surface area over which water can be directed into a well-placed storage deposit, known as an aljibe or cisterna. These were traditionally stone structures dug into the ground, often protected by a domed roof and with some kind of door or opening into which a bucket or other contraption could be lowered.
You can often find these structures on rural properties in Spain, but often they are not in use because the flow of water to them has been interrupted by disuse - channels are blocked or have eroded away, terraces themselves may have collapsed and the land itself changed shape, and the system has generally not been maintained. However, the potential for capturing a large amount of water for agricultural use is huge, if you were up for putting in the work to restore these amazing traditional systems.
Dug Well
A dug well is a well that (in the past, at least) was dug by hand and as such are generally less than 20m deep, sometimes up to as much as 60m deep, but much shallower than a borehole. They access the water table, which is the uppermost area of the ground in which water saturates rocks and fissures.
It can vary seasonally depending on the pressure of the underground water. The water table forms at the point where the underground water pressure is equal to the air pressure. In drier times, the water table may be lower and in wetter times, it could even be as high as the ground surface.
A dug well is a low tech solution which taps into this source of water, and has served communities over thousands of years.
There is always some uncertainty with these wells as to how they will recharge and perform in very dry years, unless you intimately know the water table of the area. As you can imagine, it can be really hard to know how a well will perform in dry years before you buy, unless you happen to be viewing the property during a record-dry period. You might also struggle to know the recharge-rate whilst looking at the property. It's not like you can ask the owner to pump out all the water from their well so you can measure how fast it refills. Well, I guess it's always worth asking but my guess would be that they would say no.
Sometimes you will find wonderful contraptions installed for lifting water out of these wells and channeling it into the fields, which are super cool but generally these days you would just lower a pump into the well and pump your water out.
Depending on whether the well is covered, dug wells need maintenance every now and then (maybe every 5-10 years?) to remove silt and mud from the bottom and improve their performance.
You would probably not use well-water for drinking unless you were getting it tested regularly and filtering it correctly. It's so much easier and safer to fill up jerrycans at a public spring for your drinking water to be sure you are drinking safe water.
Borehole
You might be lucky enough to have a borehole already drilled on your property. A borehole reaches below the water table to lower-level groundwater, usually perforating a pocket of water at 100+ meters below the surface. The depth of the borehole really depends - even in neighbouring properties, groundwater may be accessible at quite different depths.
You could choose to drill a borehole if you don't already have one. This can cost up to €30,000 but guarantees you a reliable, free and independent source of water drawn from a generally clean, healthy body of water that's been long underground. However, bear in mind that permission is needed to install a borehole and sometimes powerful pumps are required to extract this water and pump it to the surface. In an off-grid situation, the energy needs of your pumping system will need to be taken into account and the whole water-energy system designed accordingly.
Agricultural Water
Some properties are connected to agricultural water in some capacity. This is the case for us. Usually this water passes through a number of properties and there is an arrangement in place as to who uses the water when, who opens their gates at what time, etc. This water might be metered (albeit sometimes in a very informal way, scribbles in a logbook type of thing) or it might be free.
Natural Spring
There might be a natural spring on your property, which is great! I don't know of anyone in our area lucky enough to have a natural spring, but I did once look at a property which was right next to a municipal spring which had a very abundant flow, and apparently the spring used to belong to the property itself but was later claimed by the town as municipal property and separated, and it's now a municipal spring. Which makes a lot of sense, in a dry area like ours, such a special resource should really not be private property. However, there was a very cool feature where the overflow from the spring (which was a lot) ran in a channel through the basement of the house, providing abundant free water to the house and land for drinking, irrigation and filling a swimming pool, before carrying on through the channel to other fields and agricultural lands.
Why did we not buy this property? It was way out of our price range and too close to town for our taste, but I just share this example to give you an idea of some of the surprising water setups that you might find once you start looking at properties. And naturally, nothing about this water situation was mentioned in the property listing - it was a fun surprise when we went to visit.
Anyway, back to natural springs. In wetter areas of Spain, you might be lucky enough to have one or even more on your land. Sometimes it can be hard to find them and you might have to go hunting. Often they will be at a low point, whereas you want water at a high point, but that's a small obstacle to overcome.
Lakes and Rivers
Properties close to lakes and rivers may have the right to take a certain amount of water for agricultural purposes from these lakes or rivers. I don't actually know of any instances of this in our area, but I understand it is a possibility in some areas of Spain. You would need to pump the water to a storage location on your land, respecting the times and volumes that you are allowed to withdraw water.
Water Deposit
Another low-tech option is having a large capacity deposit and paying a water truck to come and fill it up. This can work really well for properties which mainly just need water for the household needs. A 10,000l deposit can be filled for around €100 and you can work out how long that'll last you. Many properties come with these structures ("aljibes"), sometimes below the house, often they are already fit for purpose or they might need some work to install a new lining or fix leaks, etc. Or you could construct something new, or buy some large tanks and connect them together to get your desired capacity. Bear in mind these deposits should be completely sealable, but also accessible inside for cleaning/repairs. Usually these deposits are set up to collect rainwater and the water truck is your backup option.
I have found that often the water situation is not explained in property advertisements. I don't know why this is, it seems like the first thing anyone would want to know. Don't assume that no mention of water = no water. It's worth phoning and asking.