What many people don’t realise is that a water source is going to determine a lot about a farm. When planning what and how much you can grow, how many harvests you will get and how you could irrigate – it all comes down to your access to water and how you plan to use it.
What type of water source do you have?
There are two main types of water source defined by how close the water level is to the ground:
A surface water source is easily accessible from the surface, with the water levels within 7m (22ft) of the ground. Examples of these are a lake, river, pond, shallow well or underground water tank. Surface water sources can have water lifted out with a surface water pump that is placed on the ground next to or above them.
A deep-water source is harder to access from the surface, with their water levels deeper than 7m (22ft). Examples of these are wells and boreholes. Water must be pushed up and out from these water sources using water pumps that are submersed into the water.
The depth of your water source is a very important element to consider. It will determine what type of water pump you need and the flow rate that can be delivered.
The deeper your water source the more energy will be needed to pump water up and out. Surface water pumps are optimised for high flow rates as they only have to lift water up from shallow depths (up to 7m (22ft)). If your water is further down than 7m then you will be limited to submersible pumps.
And don’t forget – your water level may not stay the same throughout the year.
How does the water level in your water source fluctuate?
The water level is not going to stay the same – from short term changes throughout the day, to long term seasonal shifts. You need to be aware of these changes so you can manage your water use.
Short term fluctuation
As you pump water out you may find that your water level drops, this will be particularly noticeable in a well or borehole. It’s a good idea to record your water levels to make sure you know when water might run out and what the recharge rate is (how long it takes to refill and/or for the water level to return to normal).
Dry running of pumps
If you know your water source is likely to run dry during an irrigation session, then it’s important to be sure that your water pump can handle this. Not all water pumps can ‘run dry’ (where they are on but not pumping water) as this will cause them to overheat and break. There are water pumps on the market – such as our range of solar water pumps – that can handle running dry, so you never have to worry about unexpected downtime or maintenance costs.
Long term or seasonal fluctuations can be planned for too, first by knowing when there are drier times of the year. What is important to consider is if your water levels could drop below 7m (22ft) deep during these drier spells. If you know it will, then you need to make sure you can still pump water from these water sources during this time.
With ever changing climate conditions it is getting harder to predict when we might have longer dry spells and droughts. Keep a watch on longer term weather forecasts and monitor the impacts on your own water sources.
One more thing to consider is not to pump too much water at a time. Over abstraction of water will mean that you could make it run dry without it having a sustainable way to refill. This leaves you without water when you need it and wasting water when you have it.
How can you save water and use it more efficiently?
To help mitigate the impacts of any drier periods – both expected and unexpected ones – and reduce the risk of over-abstraction, there are many ways we can be smart with water use on our farms.
Some easy and popular ones are:
1. Use more efficient types of irrigation. Drip irrigation is one of the most efficient types of irrigation, as it delivers a slow but steady amount of water to the base of your plants. We have another blog that goes through different types of irrigation if you want to learn more.
2. Water harvesting is the practice of collecting and storing water on your farm during wet and rainy weather. Using gutters and tanks to store water means you’ll have more access to water during the drier periods.
3. Irrigate at cooler periods of the day. This will reduce evaporation so you need less water to irrigate your plants properly. If you are using solar water pumps, this could mean pumping water to raised tanks during the sunniest periods to make the most of the free energy and then irrigate during dawn/dusk
We have some helpful blogs if you would like to know more about how to save water and get more crops per drop across your farm. If you have any particular questions about your water source and the crops you are wanting to grow, it can be helpful to get a local expert out to provide a farm survey and tailored information about your farm.