Rainwater harvesting    

Rainwater harvesting is a simple idea: collect rain that falls on roofs, channel it through gutters, and store it in tanks for later use. The concept is the same as a garden water butt; but scaled up!    

The type of water filtration needed is determined by the purpose of the water. For watering crops, or washing down yards, a simple first flush diverter is usually enough. This is a device which removes leaves and debris. For food processing water, a finer filtration and UV treatment may be required.   

Rob says, “It’s been absolutely game changing having the rainwater tank. It’s very tough and bomb proof, I’d 100% recommend getting one to other farmers. Since we’ve had the tank, we haven’t needed to use an ounce off the mains for spraying.”   

A 180m² roof area shed can capture around 117,000 litres of rainwater each year. That is about equal to a year of drinking water for 10 cattle, or enough for spraying 1,170ha. It could save a farm £257 each year (based on mains water at £2.20 per m3). Costs vary depending on what a farm already has. If guttering and recycled tanks are used, many systems pay for themselves within a year.   

At Rob’s farm we supported the implementation of a rainwater harvesting system in 2022. We contributed towards 50m of deep guttering, a first flush filter, and a storage tank to collect water from about 540m² of roof. That single system now supplies all the water needed to spray his 280 acre mixed arable and cattle farm.    

Rob says, “We ran out (of water) once last autumn and that’s the only time. I managed to do all the spraying that I needed, realised the tank was almost empty, but then there was no more left to do. It rained and I didn’t need to use any tap water.    

“We’re thinking about expanding our rainwater harvesting. We’re able to apply for a capital grant to fund more big rainwater tanks so that we can start using rainwater for cattle drinking water in the fields, rather than cattle having access to the ponds. This will keep the cattle (and their droppings) away from clean water within the pond.” 

Regenerative farming practices   

Water management doesn’t stop at the farmyard. Out in the fields, soil health is everything. Depending on how soil is managed, it can act like a sponge, absorbing rain and slowly releasing it. Or it can act like a block of concrete, shedding water and causing runoff. Healthy soil has more space for water to filter in, less erosion, fewer drainage headaches, and more resilience to extreme weather.  

“We are just tinkering and starting with regen farming ideas but are really inspired by those further along. One of the things we did last autumn is put cover crops in, with the view that the roots of the turnips and mustard etc reduce soil compaction without the need of machinery.   

“Due to a small spraying mistake, we have witnessed the difference it has made as we could see to the inch what got sprayed off because water is sat on the field. The moment you go to where the cover crop is established all the water is draining away. I have spent a lot of time fiddling about with draining rods trying to move water off fields, but the heavy machinery has compacted the soil and water will run off sideways instead and go into the ground. If we can correct that by removing the machinery and getting plants to do the job, its brilliant.”

General farm infrastructure improvement   

Beyond fields and tanks, small upgrades across a farm can have huge impacts. Good capacity guttering, cross drains to protect tracks, and repairing broken concrete and roofing over livestock handling areas all improve day-to-day operations while reducing pollution risk.  

Directing rainwater can stop it taking up capacity within slurry pits, reducing the likelihood it will overflow in storms. It can also reduce the erosion, lengthening the life of tracks and reducing potential pollution inputs into ditches and streams.  

“Replacing the concrete that was lifting has made a huge difference to the smoothness of operations, moving cattle about much better. Smoother yard to manure around means we are not dropping feed off the front of the tractor or straw off the trailers.   

“When we have cleaned sheds the tidying up of the yard is so much easier, we sweep the concrete and it looks pristine again. Before you could not clean half of it up as the concrete was so rough and cracked.” 

A note from Thea Margetts

Every farm is different and all of these changes need to be supported with grants and the right advice. 

We have worked extensively with landowners in the Whiston Brook and Marchington catchment. This year we are supporting a farmyard improvement scheme, gateway resurfacing, and running training events for farmers and landowners in Marchington. These actions are strengthening local farms, protecting water quality, and helping to build a more resilient landscape for the future.