A guide on how to harvest rainwater on a farm

A guide on how to harvest rainwater on a farm

A lot of farmers carry out rainwater harvesting on a farm for use for sprayers, washdown, pressure washing and water for dairy and yard washdown.  A rainwater harvesting system collects, filters and stores rainwater reliably until it can be used.  Our rainwater harvesting systems are designed to accommodate for livestock and arable farms to reduce the dependence on mains water supply.

Rainwater Harvesting for Livestock Farms

Livestock farms can use large amounts of water form dairy washdown, pressure washing and livestock watering, so rain harvesting is a worthwhile investment.  A study done by Warwick University suggests that on dairy farms, drinking water accounts for 50-75% of all water used with a dairy cow drinking up to 32,000 litres per year.

Using rainwater for livestock can be a worthwhile investment to cut down on water bills, with a borehole or mains water top-up, rainwater harvesting can be used for many livestock waterings uses from the many buildings which they have to collect water.

Enduramaxx works with rainwater system installers across the UK to provide rainwater-harvesting systems available for farms, from smaller DIY rainwater systems and to more expensive pumped systems with mains water/borehole back up supplies which with filtration and UV treatment used for livestock drinking.

As well as which helps minimise the environmental impact on the farm, rainwater harvesting can minimise the amount of surface water and water entering slurry pits resulting in less capacity being taken up by clean water.

According to an ADAS report on a Derbyshire farm which spent £12,500 on a borehole, pumps, control unit and buffer tank with the equipment is housed in an existing building, with mains backup supply was able to make savings in water costs of £6,000 in the first year.  On this installation mains, water can still be used as a back-up supply, if the borehole supply failed, and the buffer tank had run out of collected rainwater.

Rainwater Harvesting Return on Investment

A common misconception of rainwater harvesting any roof can be used for rainwater harvesting.  Although this is right up to a point there are factors which affect this form the type of roof, accessibility to gutters, area for storage tanks and pumps and filtration which may be required.

Factors which affect ROI for rain harvesting systems include

• Amount of rainfall you get – some parts of the country get greater rainfall than others.  The west side fo the country areas have greater potential for rainwater harvesting.  Rainfall statistics for your location are available to view on the Met Office website and when used with our rainwater calculator online here can start to give an estimate of how much you can save.
• Roof area, type and pitch of roof – the roof size, type and downpipe locations will influence the efficiency of gathering water.  A low pitch roof will collect water more effectively with suitable guttering as water can be lost with too much water flowing through the downpipes too fast.  Location of downpipes affects where tanks can be located.
• Installation & accessibility of water tanks – depending on how much work is required on the downpipes, having the tanks in the correct place makes water reuse for sprayers easier.
  Rainwater harvesting can be viewed favourably by planners on greenfield dairy projects. For example, a rainwater-harvesting system is easier to install on a new unit with the correct amount of downpipes.
• How much water do you use? – before you can work out how much you can save, running over your old water bills with a rainwater harvesting installer, reviewing how it’s used and uses for rainwater will help working out the ROI of a rain harvesting system.

Above Ground or Below Ground Rainwater Harvesting Tanks?

With many domestic applications, where space can be an issue, below-ground storage can offer a put of side solution.  However, many industrial or agricultural installations where the harvested volumes are much much greater, space is not generally an issue.   To store large volumes of water underground is very expensive will require pumps to get the water above ground to use it.  Generally, in industry and agriculture, the main volume of harvested roof water above ground with several tanks interlinked with a mains top-up where the use of the exceeds the water stored.

Why do I need to filter rainwater?

Rainwater filters are important in a rainwater harvesting system to filter debris from the rain-water as it flows from the collection roof before it enters the storage tank.  These rainwater harvesting filters prevent the leaves and moss entering the tank and save a build-up of sediment in the tanks.   These rainwater filters have 2 inlets for incoming water which are 4?  and 6? on the larger 800m2 roof area filter.  On the 450m2 and 800m2 roof, filters have an overflow taking the leaves and moss away to a drain or soakaway and an outlet in the bottom of the filter for water to enter the storage tank.

As a guide rainwater filters range from less than £100 for a simple mesh or lid filter to more than £800 for wall mounted filters filter out leaves, moss and larger particles.  These larger filters are generally automatically self-cleaned the mesh using about 10-15% of the water collected to take leaves and moss to a soakaway or drain.  To avoid any contamination through the surface water collected, we advise the water is passed through a UV filter prior to being used for animal drinking water or parlour washing.

How Much Rainwater Can I Collect?

Rainfall statistics for your location are available to view on the Met Office website.  Our rainwater calculator can be viewed online here

What Are The Most Popular Water Tanks?

View our full range of rainwater harvesting tanks here

For more details on rainwater harvesting on a farm, pricing for water tanks or Camlock fittings for your sprayers – please get in touch.