Many of us wonder if and how we can continue to use our hoses during a hosepipe ban, and whilst using a mains-water connected hose during a hosepipe ban is illegal, there are indeed other ways that we can continue to use a hose; say hello to rainwater harvesting!
With global warming showing no signs of slowing down, droughts and hosepipe bans are becoming commonplace in the UK and can be a recipe for disaster for gardeners, homeowners and farmers alike.
The good news is that with just a small investment, homeowners, allotment holders and commercial/agricultural landowners can begin harvesting rainwater to ensure there is a good supply of water for plants, crops and livestock during times of drought.
Not only will harvesting rainwater allow you to continue using your hose during hosepipe bans, but it will bring many other benefits throughout the rest of the year too, which we will discuss in this article.
What is Rainwater Harvesting?
Rainwater harvesting refers to the collection and storage of rainwater using a rainwater harvesting tank or water butt, instead of letting it disperse into the ground.
By harvesting this free resource, we not only provide ourselves with an independent water supply during drought or times of regional water restrictions, but we are also supplementing the mains water supply and hence reducing water usage bills.
Additionally, with a harvested source of water, you be able to continue using your hose during a hosepipe ban whilst your water bills will be reduced too. Hence having a rainwater harvesting system installed often works out to be a very worthwhile investment!
How Is Rainwater Harvested?
Generally, rainwater is collected from guttering and/or roof-like surfaces that have been attached to existing buildings or walls and redirected to a water storage tank, either sat above the ground or set below.
There are many different types and brands of tanks which can be used to harvest rainwater, from IBC tanks which are great for allotments to larger water storage tanks such as Enduramaxx tanks which are great for commercial and agricultural use.
For home users, decorative water butts such as the 3P Technik range can provide a more stylish option, with their range including stunning modern and traditional styles to suit a variety of gardens.
The harvested rainwater can then be gravity-fed or pumped to its final destination. A hose can be attached to the tap on your rainwater storage tanks and the water can be used for watering plants or for livestock and crops, evening during a hosepipe ban!
The Benefits of Harvesting Rainwater
Rainwater is an asset that saves money and reaps dividends for the environment
On top of reducing water bills and allowing you to continue using your hose during hosepipe bans, there are many other benefits to ‘saving’ and harvesting rainwater.
Some of these include:
1 Reduced Water Bills
To most people, the main and most obvious benefit of harvesting rainwater is that aside from the initial investment, the water is free and hence water usage and bills will be reduced!
In times of a cost-of-living crisis, soaring bills and inflation, reducing water bills can help ease some of the pressure that many of us are experiencing right now and allow our money to go further.
3 Good For The Environment
Harvesting rainwater and using it in your garden or for agricultural uses can not only help to reduce bills and running costs, but it is also much better for the environment.
Rainwater doesn’t need to be chemically treated, processed and delivered, all of which result in mains water supplies having a high carbon emission rate that harvested rainwater doesn’t.
4 Better for plants, vegetables and livestock
Rainwater has a balanced pH and is free from chemicals that are found in mains water including drinking water, such as chlorine and fluoride.
For this reason, rainwater is much better for watering plants and crops.
Because rainwater is naturally soft, it is also better for livestock and in residential settings, it can be used for watering back garden poultry too.
Mains water would need to be filtered to have a similar effect on plants and livestock, but even then, some dissolved minerals, nitrates and other substances may remain.
5 Reduce Pressure on Storm Water Drains
Because the water collected on guttering is filtered to remove debris before it is harvested (referred to as pre-tank filtration), pressure is reduced from stormwater drains.
6 Water is Usable in Many Applications
Harvested rainwater is suitable for many applications around your home or allotment including pressure washing, irrigation, dust suppression, spraying and livestock.
It can also be useful when access to the mains water supply is limited, such as in brownfield sites or on development sites. In these settings, it can be collected and harvested with IBC tanks.
7 Allows you to continue using your hose during a hosepipe ban
Whilst it has already been mentioned above, how could we not reiterate the fact that harvesting rainwater allows you to continue using your hose during times when their use is banned!
How Much Water Can Be Saved with Rainwater Harvesting?
Whilst throughout most of the year, outdoor water consumption accounts for just 7% of the total amount of mains water we use, during the summer months, this can rise to as much as 50% or more, according to Waterwise.
Some sources indicate that in residential settings, up to 55% of mains water used in the UK could be substituted for harvested rainwater. That’s one very large reduction in water bills!
According to garden designer Clive Hall, who spoke about this topic with The Guardian, harvesting rainwater can reduce mains water usage by between 35% and 55% depending on the season and amount of rainfall.
This figure increases to an 85% reduction in mains water usage when considering the amount used for commerce, industry and agriculture. In conclusion, much of the water we use does not have to be purified or come from the country's mains water supply.
How To Calculate How Much Water You Can Save
The following formula and calculation examples give you an initial estimate of the maximum water harvesting potential:
Average annual rainfall for the Southwest 850mm-950mm as per the Met office
Approx total annual rainwater harvest potential in cubic metres = The roof area (footprint) in square metres (m^2) multiplied by the average annual rainfall in cubic metres (m^3)
The average monthly rainfall capture = the approx. annual rainwater harvest potential in cubic metres (as calculated above) divided by 12
Calculation Examples
For our calculation examples, we will use data from the South West, where the average annual rainfall is 850mml= 0.85m^3. We will use this figure for our annual average rainfall in the calculation examples below:
Example 1: Typical 2.44 x 1.2 (8x4ft) = 2.93 Metre Squared Garden Shed
● e.g. 2.93m x 0.85m Cubed = 2.49m Cubed (2490L of water saved per Annum)
● divided by 12 = 153L of water saved per month on average.
Example 2: Average UK 3 Bedroom Home with a roof area measuring 70m^2
● e.g. 70m x 0.85m Cubed = 59.5m Cubed (59500L of water saved per annum)
● Divided by 12 = 4958L per month average.
Looking To Have a Rainwater Harvesting System Installed?
If you’re based in the South West and looking to start harvesting your rainwater, we can supply and install a complete rainwater harvesting system in Devon, Dorset, Somerset and Wiltshire. Just drop us a message and we'll be more than happy to help!
We supply only the highest quality water tanks from Enduramaxx or for water butts, 3P Technik, the latter of which are great for residential customers who want their tanks to match and complement the décor of their homes.
Our range of Enduramaxx tanks includes underground water tanks, rainwater tanks, baffled tanks, potable water tanks and horizontal transport tanks.
We also offer a large range of reconditioned IBC tanks which are perfect for harvesting rainwater that can be used for watering flowers and plants not intended for human consumption.
The spring and summer are a great time to start harvesting rainwater, which is often when hosepipe bans are introduced too.
If you’re not based locally then check out our guide next month on how to set up a home rainwater harvesting system in the garden, or check out our range of water storage tanks!