Future Surface Water Management

Rainwater Harvesting diagram

In a recent edition of Builder Merchants Magazine, Glyn Hyett, Founder-member and Director of the UK Rainwater Management Association, writes about how to mitigate the problems of Winter floods and Summer droughts.

The solution, Glyn summises, is two fold. To “… store sufficient surplus Winter rainfall to meet subsequent summer requirements without relying upon river extraction.” He goes on to say that “Taking an integrated approach to SuDS and water shortages would be much more cost-effective than treating floods and droughts as separate issues”. In times of drought, rain water is a valuable natural resource.

Making use of stored water (after it has been temporarily stored in cisterns) for non-potable purposes such as flushing toilets makes sense from a sustainable point of view.

The illustration at the top of this post shows infiltration, water gardens and rainwater harvesting (RWH) being used as the primary Sustainable Drainage System (SuDS) tools. The overflow of the RWH component of the system can be used to help supply downstream communal systems; these serve properties with a low roof-to-occupancy ratio, which do not harvest sufficient rainfall to meet residents’ non-potable needs. Balancing ponds or swales to accommodate exceptional weather events then complete a highly cost-effective system that provides a raft of environmental and amenity benefits.

Read the full Future Surface Water Management article as a pdf document.


Flooding and Drought Avoidance must be linked, says UKRHA

13A - Building Engineer_page3_image3Terry Nash, the Director of the UK Rainwater Harvesting Association (UKRHA) this year wrote an open letter to the Prime Minister providing an outline for a plan to tackle both flooding and drought as one issue.

Following the hugely disruptive flooding of this winter, Government announced its plans to deal with the environmental and economic effects with a £540 million recovery package, but the UKRHA has urged David Cameron to take into consideration the obvious links between flooding and drought.

13A - Building Engineer_page3_image2The UKRHA mentioned the drought of 2012 combined with the more recent flooding to support the earlier predictions of The Environment Agency in its 2010 publication “Water for People and the Environment”, which argued that winter flooding and summer droughts were to increase in regularity.

The argument that drought management and flood avoidance are simply two sides of the same coin seems obvious, but current policies do not reflect this. UKRHA is urging government to incorporate plans to cope with drought into its new flood avoidance strategies, and points out worries about the future of water management in the UK as funding delays and Housing Standards reviews are undertaken. With the scrapping of the Code for Sustainable Homes, it is unclear what Government’s water management policies will become.

How rainwater harvesting can help

Rainwater Harvesting can be of use in two ways: by collecting water as opposed to allowing it to run off over the land, flooding can be prevented. The collection of rainwater will also benefit us in times of drought as the stored water can be used to keep crops alive until wetter weather returns.

Domestic rainwater harvesting is ideal for use by individual households, but larger systems could be put in place to cover local areas, larger districts, and even greater regions of the country.13A - Building Engineer_page3_image4

Rainwater Harvesting FAQs

  1. 9000530K-Wall-Tank-GreenWhat Happens during a drought?

    A full rainwater harvesting system will automatically take water from the mains when rain is scarce.

  2. Is the water clean?

    Rainwater tanks have filters to remove debris and particles, so the water is clean.

  3. How much water can a system harvest?

    This depends on variables such as the catchment area and how much it rains where you are based. On average, a domestic system will cut mains reliance by about 50%, rising to around 80% for commercial applications.

  4. Why buy a system?

    Rainwater harvesting has significant environmental benefits, cutting mains demand and lowering storm water run-off. Controlling your storm-water run-off is becoming more important in the eyes of Planning departments.

  5. Can rainwater harvesting systems be retrofitted?

    The systems are best when built into the design from the beginning, but they can be retrofitted to existing buildings.

  6. Is there a danger of Legionella?

    Legionella cannot cultivate in the dark, cool, and oxygenated conditions of underground tanks.

  7. How big are the systems?

    System sizes vary considerably, and depend on the harvesting capabilities of your roof as well as the levels of use of non-potable water usage in the building.

  8. What maintenance do rainwater harvesting systems need?

    This varies from one system to the next, but is always minimal. Typically, you’ll need to wash off the filter with a garden hose for five minutes once per quarter.

  9. How long will a system last?

    The buried parts of the system will last indefinitely, and the control system, pump, and filter all have long lives and are easily replaced if necessary.

  10. How long has rainwater harvesting been in use?

    The Romans created the first rainwater harvesting systems, but those used today are based on mid-1980s’ designs.

  11. Is the modern technology proven?

    Yes – Systems fitted in Germany in the 1980s are still in use, and one benefit of the UK being behind the rest of Europe is that any issues with the systems have been worked out through all of the work done in Germany.

  12. How often will the rainwater harvesting system need to be topped up from the mains supply?

    Systems with good balances of supply and demand should only need to be topped up when it hasn’t rained for a while. Severn Trent monitored a domestic system and found it rarely needed topping up and was usually around 50% full – ideally balancing having enough water to use and enough space to hold future rainfall.

  13. What uses does the water have?

    Harvested rainwater is suitable for all non-potable purposes from watering plants, washing cars, flushing toilets, and running washing machines. In some cases, further treatment can make the water safe to drink.

  14. How much do pumps cost to run?

    A pump will normally use less than 1.0kWh of electricity to provide 1 cubic metre of water (1,000 litres). Pumping costs are around 10p per week for a 3-bed house using rainwater for WCs, gardening, and the washing machine.

  15. How much do rainwater harvesting systems cost?

    Smaller water butts used for gardening or washing cars will be significantly cheaper, but larger domestic systems cost around £1500 to £2000, depending on size. Commercial systems are more expensive, but will save more due to the greater roof areas.

  16. Is rainwater potable?

    In the UK, rainwater usually isn’t harvested to be drunk. However, some manufacturers can offer solutions to bring water to potable quality with sufficient maintenance.

  17. Are there any rainwater harvesting grants or tax allowances available?

    At the moment, there are none. However, rainwater harvesting systems do qualify for 100% capital allowance in commercial applications.

Water Butt Maintenance

9000700K Tuscan Terracotta 275l photo2Water butt maintenance is a pretty simple process, and certainly worth the little effort it takes to keep your greenery in good health. You shouldn’t need to carry out maintenance checks more than once per year, but that doesn’t mean it isn’t important – ignoring the butt’s needs will leave you with smelly, algae-covered water which your plants aren’t going to thank you for.

Give the water butt a good clean once per year (the height of summer is a good time, when rainfall is lower and you have less water to lose by emptying the tank): use the remaining water around the garden, and then disconnect the pipes so that you can reach right in to take out any debris and give the container a good scrub.

Don’t stop there – for the most effective and efficient water butt maintenance, it’s best to sort out the whole system at once instead of coming back to see to odd bits and pieces further down the line. Clean out the gutters and replace any faulty parts you come across. You could think about fitting a water butt filter to keep any plant debris to a minimum.

To stop mosquitos from laying their eggs in your water, keep the lid nice and tight – this will keep light from getting in, stopping algae from growing too.

You can use non-toxic treatments like Biotal Refresh Rain Water Butt Treatment to stop any smells or algae.

To collect more rainwater, you can add a number of water butts to each other and create a rainwater harvesting system. Slimline water butts are great for collecting water without taking up heaps of space.

Conservatives to cut funding to countryside Wind Farms

Having already laid waste to the Code for Sustainable Homes, the Conservative party is expected to announce a cut to the funding of onshore wind farms in favour of their more expensive offshore counterparts. The environmentally questionable move, which was strongly hinted at by Tory chairman Grant Shapps last week, is expected to form a part of the Conservatives’ manifesto ahead of the 2015 general election. This will put them at odds with their coalition partners, the Liberal Democrats, but will answer some voters’ concerns about the visual effects of wind turbines on the British countryside.

Scout Moor Wind Farm

Image by Paul Anderson

According to a report on wind power by the Royal Academy of Engineering (RAEng) last week, the change would result in higher energy bills. Professor Richard Green, an economist at Imperial College London and a member of the independent working group responsible for the RAEng report, has claimed that the Conservatives’ plan would lead to greater subsidies of £300,000 per turbine. Offshore turbines would be given £140 per megawatt hour of electricity produced, whereas onshore turbines would be granted £90 per megawatt hour. This would be accounted for by increased energy bills, according to Prof. Green.

In the report, the RAEng found that Britain could generate up to 20% of its electricity needs through wind farms – the grid currently supports just over half of that – before any major upgrades would have to be made to the system.

But curbing onshore wind turbines is seen by the Tories as a vote-clinching move. In a report from the London School of Economics last week, it was found that wind farms can decrease the value of a home within a radius of 2km by as much as 12%. However, this was just days following a contradictory study by the Centre for Economics and Business Research and RenewableUK.

Ultimately, according to RAEng group member and professorial fellow in engineering at Lancaster University, Roger Kemp, the public will look most closely at the impact of the change on their finances. He said: ‘If we’re being serious about decarbonising the grid and doing the things the government says it’s committed to doing about climate change, then we’ve got to find some way of getting electricity without burning fossil fuels – coal, gas, oil and so on. The alternative to wind power is solar power, but our peak electricity requirement is at about six o’clock in the evening in December, and you don’t get much out of your solar panels in December at six o’clock.’

The focus on finance is of course important to all, so with onshore wind farms costing significantly less money and potentially supplying a great amount of our electricity there is still hope that the public will opt for the environmentally beneficial option in next year’s general election.

Domestic Renewable Heat Incentive (RHI) Launches

After what feels like a long wait, the Domestic Renewable Heat Incentive (RHI) has been launched today, offering cash incentives to people who heat their homes or water with a renewable heating system.  Payments are made to households who install low carbon systems to attempt to lessen the divide between those stuck using fossil fuels and those who can afford the more expensive renewable heat alternatives.

The scheme is open to any kind of homeowner, including social and private landlords, self-builders, and those both on and off the mains gas grid and is hoped to encourage a reduction of carbon emissions in the UK.

The scheme currently covers the following technologies:

  • Biomass heating systems
  • Ground or water source heat pumps
  • Air to water heat pumps
  • Solar thermal panels

Only one space heating system can be used in conjunction with the scheme per household, but it is possible to apply for solar thermal for hot water and a separate space heating system.

Rainwater Harvesting neglected by Government

There are currently no support schemes in place for rainwater harvesting, which is beneficial in a number of ways including reducing energy consumption, preventing localised flooding, and providing water during the ever-more-frequent droughts that the UK, especially the south-east, is facing. With the scrapping of the Code for Sustainable Homes, support for such vital measures is lessening.

Image by Palamedes Ltd

3P Technik Water Butts: a Brief Guide

Rainwater harvesting to for your garden and plants is the most natural method of making sure your environment is properly hydrated. Avoiding watering the garden with drinking water means using less energy, losing less money, and better benefiting the environment.

Why use a Water Butt?3P Tuscan

  • When properly set up, a water butt is able to provide all of the water necessary to keep a garden thriving during the warmer, longer summer days.
  • Transferring rainwater from the butt to your plants with a watering can, you can be certain you are not using any more water than is needed whilst avoiding unnecessary waste of high quality drinking water.
  • Using a water butt will drastically reduce your carbon footprint. At the moment, the average household in the UK receives half a tonne of water from the mains supply each day, incurring massive costs in money and energy.
  • If each and every home in the UK were to rely at least partly on a water butt, around 30,000 million litres of water could be conserved each summer – that’s sufficient to fill the Bewl Water reservoir which dried out in the summer of 2006.
  • Naturally acidic rainfall is actually more beneficial for our plants than the chalky, filtered  water we prefer to drink, so everyone and everything benefits!


The quality water butts available from Water Butt Shop are designed to fit inconspicuously into a vast array of settings, from cottage gardens to city centre yards. The 3P Technik water butts are available in a range of looks including wood effect, stone effect, and minimalist space saving designs. They are all made using the highest quality, rota moulded polyethylene, each with brass threaded inserts.

To decide how small or large a tank you will need, work out the amount of water you are likely to need depending upon your plant varieties and the size of your outdoor areas. A number of water butts can be connected together if needs be.

Our Range

3P Utility TankProviding for house builders, developers, and retailers, the products we offer vary in size, cost, and appearance. Starting at £168 (inc VAT) for our 275 Litre Tuscan Water Butt (above) to £618 for our 1500 Litre Utility Tank (left) and more, there is an option for every application.

For a full list of the products we currently have in stock, visit the Water Butt Shop.


All of our water butts will be shipped free of charge.

Filtered Rainwater Harvesting for Gardening

9000580K evergreen dark brown 475l photo6There are a few simple steps you can take when harvesting rainwater to use as a part of your sustainable gardening routine which will ensure you keep your supply safe, clean, and constant. Harvesting rainwater as it travels through a downpipe is achieved by diverting the flow halfway down from the pipe into a tank. It is considered best to filter the water before it travels from the filter into the tank itself:

  • Filtering the water will remove any leaves or other organic matter from the water, which is great for reducing the risk of disease carry-over and allow harvested rainwater to be used on even the least mature plants, enabling truly sustainable gardening for the entire garden.
  • Filtration will prevent any algae or sludge from growing within the tank, avoiding the water turning ‘green’ without having to resort to chemical anti-algae solutions.
  • Filtering the water will take out any large particles so that it is easily and safely pumped, making sustainable gardening easier than ever.

How does rainwater filtering work?

As rainwater is travels down the downpipe running from the roof, it channeled through the filter entrance to the sieve cartridge where the dirt is then rinsed away into the sewer. The clean water is then taken via the cartridge’s outlet channel into storage.

Filter tankThe 4 cleaning steps of sustainable rainwater for gardening:

  1. Filter the water before storing in the tank to remove the larger particles. This keeps blockages down and provides a good enough quality of water for keeping your plants in good health.
  2. The calmed inlet prevents the particles settling at the bottom of the tank getting mixed up with the rest of the water, and it keeps oxygen circulating around the tank so that the water remains fresh.
  3. The overflow siphon skims the top layer of the water, where small particles such as pollen will collect, to keep the water oxygenated.
  4. The floating intake takes water from the cleanest part of the tank, which is just beneath the surface of the water.

Rainwater Harvesting without the Code for Sustainable Homes

9000680K barrique dark brown 270l photo8Here in the UK, our water supplies are under a great strain due to a number of contributing factors. The main identifiable issues are our increasing individual consumption of water, an ever-expanding population, and alterations to the patterns of rainfall in the country as a result of recent climate change.

Such issues have been reflected in a number of different Government policies. Legislation such as the Building Regulations, and documents such as the Code for Sustainable Homes and BREEAM have called for rainwater harvesting schemes to be implemented to cause mains water consumption to be reduced. Economising methods and the substitution of potable water for harvested rainwater in applications such as toilet flushing, clothes washing, and garden watering have all been suggested as water-saving initiatives.

The response of industry has been largely to reconfigure the ancient historic practice of rainwater harvesting (RWH) in a modern and very reliable way which automatically cleans, stores, and supplies aesthetically pleasing (though not potable) water to sundry services on demand. This is accomplished by harvesting the rainwater which falls on the roofs of homes, businesses, and other buildings.

However, the Code for Sustainable Homes – one of the main advocates for rainwater harvesting in the UK – came under threat late last year as it was proposed that it could be scrapped and partly folded into the Building Regulations instead. The Environmental Audit Committee chairman Joan Walley said:  “The Secretary of State should think again before demolishing the Code for Sustainable Homes. It has been a big success in driving up home building standards.

9000357K noblesse charcoal 270l photo10“Hundreds of thousands of homes have to be built in the coming decades. Smart energy and water saving measures – which will ultimately save homeowners money on their bills – must become the norm if we want our homes to be fit for the future.”

Without the Code, it is feared that standards will drop in sustainable building and that the importance of rainwater harvesting in particular has not been appreciated.

Fionn Stevenson, head at Sheffield School of Architecture, has said: “My main concern is that the government, in its haste to ‘simplify’ everything, does not throw the ecological baby out with the ‘red tape’ bathwater.

“It concerns me, for example, to see that simple, passive rainwater harvesting is dropped in ‘areas with no water shortages’ – completely missing the point that such moves also save energy and resource use by localising water use, and provide much needed resilience if there is a central failure in the waterworks.”

Find us on Facebook and Twitter to keep up with our latest Eco Updates!

The Benefits of Rainwater Harvesting with WaterButtShop

9000700K Tuscan Terracotta 275l photo12Rainwater harvesting to take care of your garden, plants, and animals is the most natural way of ensuring that your garden is sufficiently watered. By not using drinking water for non-drinking purposes, you will use less energy, spend less money, and do a better job for the environment.

Why use a Water Butt?

  • When properly used, a water butt is capable of providing all of the water you need to keep your garden thriving throughout the long, hot summer months.
  • Using a watering can to carry rainwater from the butt to your plants, you can ensure you do not use any more water than is necessary whilst avoiding wasting your high quality drinking water.
  • Your carbon footprint will be significantly reduced. At the moment, the average household in the UK has half a tonne of water delivered to their home each day, costing large sums of money and energy.
  • If all households in the UK were to use a water butt, around 30,000 million litres of water would be saved each summer, which is enough to fill the Bewl Water reservoir which dried out in the summer of 2006.
  • Rainwater is actually better for our plants than the filtered water we drink, so everyone and everything benefits!


9000520K wall tank sand 800l photo9The high quality water butts on offer at WaterButtShop are designed to fit unobtrusively into all kinds of settings, from country gardens to town centre backyards. The 3P Technik water butts are available in wood effect, stone effect, and space saving designs and all are made from high quality, rota moulded polyethylene, each with brass threaded inserts.

To decide what size tank you will need, consider the amount of water you are likely to need depending upon your plant varieties and the size of your garden area. In many cases, a number of water butts can be connected together if needs be.

Our Range

Providing for house builders, developers, and retailers, the products we have on offer vary greatly in size, cost, and appearance. Ranging from £168 (inc VAT) for our 275 Litre Tuscan Water Butt to £1,999 for our 5000 Litre Wall Tank System, there is a perfect option for every application.

For a full list of the products we currently have in stock, visit Waterbuttshop.co.uk.


All of our water butts are shipped free of charge.