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  • Rainwater recycling systems are often designed for use with an irrigation system. However, what happens when we have a dry spell and you need the irrigation system most? The water runs out! To overcome this, a mains water top-up system can be used. This adds a pre-set amount of water into the storage tank when the water level is low – generally just enough to give one day’s irrigation. Then, if it rains, there is still plenty of room in the tank to catch the rainwater. The Water Regulations, which is the legal framework for the use of mains water in the UK, are very strict about ensuring the public drinking water supply is not contaminated by rainwater. Therefore, it is not possible to simply connect the water supply to the tank – there must be a physical air break between the rainwater tank and the public mains. An air gap can either be achieved by an air gap in an above ground tank or via a tundish assembly that allows the water to fall into an underground tank by gravity. Underground tanks must also have an alarm system installed to warn of an overflow situation. This is to prevent the mains water that is being added to the tank flowing down the drain and being wasted. Access Irrigation manufacture two types of mains water top-up system, one for above ground use and one for below ground use. Each has a level sensor that can be set to trigger the top-up when the tank level falls below a pre-set amount.

  • What is a borehole? A borehole is a very narrow hole drilled down through the earth. For irrigation purposes the borehole is drilled to reach the water in an aquifer, it is a much more efficient way of reaching water than digging a well. An aquifer consists of porous rock that is filled with water. Before a borehole is drilled it is important for a survey to be done to ensure that the likelihood of finding water is worth the drilling costs. In the UK, the advantage of drilling a borehole is that the water extracted by the landowner is free. It is also not subject to hosepipe bans like mains water. However, if more than 20m3 of water per day is to be extracted, the Environment Agency must be informed and a licence applied for. As a single aquifer might have many boreholes drawing from it, the Environment Agency restricts the amount of water that can be extracted to ensure there is sufficient for higher priority needs and that the environment isn’t unnecessarily damaged. How does a borehole work? The borehole taps into the underground water source and a pump is used to bring the water to the surface. Generally a borehole will be lined with a porous plastic liner to ensure that it has a very long life and that the sides do not collapse. Borehole pumps are very narrow to allow them to be dropped down the hole that has been drilled. However, when they need servicing they have to be brought back up to the surface, which is time consuming. How to treat borehole water Water from a borehole may need to be treated for chemical imbalances eg. high levels of iron and may also need to be filtered to remove sediment. How much filtration is required is dependent on the flows and how clean the water is. As the water had been filtered as descends through the rocks, it is often very clean, in which case a simple screen filter would be added after the pump. Simple screen filters are only a few pounds, for dirtier water, high capacity semi-automatic filters start at several hundred pounds.How much does a borehole cost?The cost of the borehole depends on a number of factors including the depth to be drilled and the ease of access for the drilling ring. A ballpark figure for a 60m deep borehole is between £7,000 and £10,000 Could you save money with a private borehole water supply? How much money you will save depends on how much water you need to use. A 1,000m2 garden will use 3-4,000 litres a day in summer. With mains water at around £1.50 per m3 this would translate in a daily savings of up to £6.00. If we water for 120 days of the year, this would give an annual saving of £720. Extracting the maximum permitted amount per day would water around 5,500m2 of garden and save around £4,500 a year. At this point a borehole starts to look an economic option. Borehole Regulations The Environment Agency allows the extraction of up to 20m3 of water per day without an extraction licence. Above that amount, a licence must be applied for from the Environment Agency. This is a relatively complex process and will depend on how much water is available in the catchment area, balancing the environmental damage that over-extraction can cause against the benefits. Records must be kept of how much water is used and these must be reported to the EA. Abstraction covers taking water from rivers, streams, canals or from underground sources via a well or borehole. As a general rule of thumb, if you catch the water before it hits the ground eg. from a roof structure, it is yours. Once it is on the ground then the abstraction regulations apply.

  • Irrigation pumps are designed to provide sufficient pressure and water flow for an irrigation system. Sometimes an irrigation pump is specified as the main water supply is not capable of providing the pressure and flow required, this is especially true for pop-up lawn sprinklers and large sprinkler sets in horticulture. Irrigation pumps are also required where the Water Regulations require a break from the public water main - most commercial irrigation systems need this by law. The break from the mains is normally achieved using a water storage tank, generally called a break tank. Once the water is in the tank it has lost all pressure, so has to be re-pressurised by an irrigation pump. The third use of irrigation pumps is where the water source is a stream, well or lake. We shall look at each of these requirements for pumps. Mains water will only supply a finite amount of water flow and pressure. The available pressure and flow can be measured with a bucket, stopwatch and pressure gauge. The available water supply can be compared with the requirement of the new irrigation system - if the mains water supply is insufficient then an irrigation pump will be required. However, the UK Water Regulations prohibit irrigation pumps being connected directly onto the water mains, so a storage tank is also needed. The tank needs to be big enough to hold the difference between the water required on the irrigation cycle and the amount available from the mains. The UK Water Regulations require a break tank for almost all commercial irrigation systems. This is to prevent the risk of contaminated irrigation water flowing into the public mains - a situation called 'back-flow'. Generally, a break tank and an irrigation pump are used to achieve compliance. For lakes, streams and wells submersible irrigation pumps are normally used. These can be dropped into the water to draw the water out. For dirtier water sources a floating inlet can be used to ensure the water just below the surface is drawn in, as this is generally cleaner. Filtration is a must on these water sources, what type of filtration will depend on the amount of contamination in the water and also the type. Most smaller irrigation pumps are electric and are either single stage or, for higher pressures, multi-stage. On agricultural installations diesel or petrol irrigation pumps may be used. Electric pumps are normally controlled either via an auto-start unit or via a relay that is connected to the irrigation controller. With auto-start pumps it is very important to ensure that there a no leaks on the system pipework, otherwise the pump will keep turning on and off to top-up the pressure, potentially damaging the irrigation pump. Irrigation pumps are water cooled, so can be damaged if the pump runs dry. In extreme cases the pump can overheat and catch fire.  

  • Keeping football and rugby pitches in good condition is vital, and last year's dry weather demonstrated to need for an efficient irrigation system. A dry, cracked pitch becomes a heath and safety concern. With irrigation a little and often approach is important - once the pitch has dried out it is very difficult to get it back into shape. Pitches also need a lot of water - to replace the evapotranspiration losses of just one week's hot, dry weather requires 160 tonnes of water. Only an irrigation system can provide this amount of water onto a pitch. Access Irrigation have designed two watering solutions, providing water for one pitch or two pitches. Each system includes the storage tank, an industrial quality pump, underground supply pipe to a hydrant and either a travelling sprinkler or a reel irrigator. The systems can be installed with intermediate level DIY skills and require a concrete base for the tank and trenches removing for the pipe runs.

  • Access Irrigation is pleased to announce that it has been accredited with the prestigious ISO 9001 quality standard. International Organization for Standardization (ISO) 9001:2015 is the most up-to-update standard of its kind and focuses on quality management systems and performance. It assists companies in developing a management system that aligns quality with their wider business strategy. There is a focus on risk-based thinking and accountability in all organizational processes that helps improve communications, efficiency, and implementation of continuous improvement. For any company, the road to certification requires time and commitment. Access began their internal preparation for certification in Autumn 2017, by evaluating their existing procedures and aligning them with the new requirements. Since their internal documentation and procedures were already well established they only needed to make minor changes to their quality manual and overall processes and procedures to meet the new standards. Managing Director, Matthew Pearce, said that "acheiving the quality standard recognises the hard work and professionalism of everyone in the company. The standard ensures that our processes are robust and that we can focus on continually improving our service to customers."

  • The temporary ban on water use (hosepipe ban) being implemented by United Utilities from 5th August 2018 will ban the use of hosepipes and sprinklers to water domestic gardens. There are however a number of exceptions: Newly turfed areas These can be watered for the first 28 days after laying - an efficient sprinkler system will ensure that the best use is made of water, and a timer will allow the watering to be done early in the morning when evaporation levels are at their lowest. Drip Watering As drip watering systems are so efficient compared to sprinklers and hand watering, Water Companies are using hose pipe bans to try and encourage long term water efficiency. To help with this, they are allowing drip watering systems fitted with a timer to be used. All of the drippers we supply are pressure regulated, providing a highly efficient drip system that complies with the regulations. Drip lines can be supplied for borders or for baskets and tubs. A range of tap timers are also available.

  • The Water Supply (Water Fitting) Regulations 1999 provides five backflow prevention categories dependant on the risk level of the water use. The regulations require back-flow prevention devices to prevent the water on the premises being drawn backward into the public drinking water supply. Backflow may occur in a number of situations, including burst pipes in the street or cross connection of the mains water supply with pressurised supplies on the premises. An assessment needs to be made of the potential dangers to health of the backflow – if the backflow water comes from a butcher’s shop it is more likely to be contaminated than a newsagent. What is a Cat 5 break tank for? Backflow needs to be prevented as the Water Companies primary obligation is to provide safe, clean drinking water (potable water) to the population. Water quality is  rigorously tested as it leaves the treatment plant, however if the water is subsequently contaminated it may cause widespread illness or disease. Category 5 compliance is provided by a physical 'air-gap'. Water falls into the tank from the inlet valve. the height of the inlet valve above the maximum water level is laid down in the regulations. The laws of physics demonstrate that even in a back-flow situation, water cannot jump from the break-tank back into the mains water pipe. The critical provision of the air gap tank is the maximum water level. Therefore, the tanks have to have some form of weir that the water flows over to prevent the water level rising above its maximum. Type 'AA' airgaps use the top of the tank as the weir, type 'AB' tanks have a slot cut into the side of the tank for the water to pour over.  In the legislation, fluid risk category 5 covers the following areas: Fluid which represents a serious health hazard because of the concentration of pathogenic organisms, radioactive or very toxic substances, including any fluid which contains –  faecal material or other human waste: butchery or other animal waste: or pathogens from any other source.   A non-exhaustive list of examples of this include: General: Industrial cisterns Non-domestic hose union taps Permeable pipe other than domestic gardens, laid below or at ground level, with or without chemical additives Medical: Mortuary and embalming equipment Commercial clothes washing plant in health care premises Food processing: Butchery and meat trades Slaughterhouse equipment Vegetable washing Cat 5 break tanks To provide category 5 compliance, Access Irrigation produce a Cat 5 break tank and pump set. The break tank has a category ‘AB’ air-gap and the pump re-pressurises the water. An auto start device on the pump brings the pump on when there is a water demand and will stop the pump when the demand ceases. The pump set is available with a range of Lowara pumps which can be matched to the flow and pressure requirements of the project. Two units are available. The smaller unit has a storage tank that holds 91 litres of water and has a 1/2” BSP inlet thread and will handle an inflow of up to 1,200 l/h into the tank. The larger Cat 5 break tank also holds 500l of water, so the tank will hold a buffer of water is situations where demand is higher than the water inflow.

  • One of the neatest ways of installing an irrigation system is to locate all of the control valves in underground chambers. Not only does this hide away all of the messy control valves, but it prevents unauthorised tampering with the control equipment. The only problem with this solution is when you do want to change the watering times, you have to grovel in the underground chamber. To solve this problem, a fully waterproof Bluetooth irrigation controller is now available in the UK. The controller itself is IP68 rated, so it is designed to be fully immersed in water and will control up to 4 solenoid valves, plus a master vale and a rain sensor. The app itself will store the details of up to 200 controllers, as well as manually start, stop or suspend the controller from up to 10m away. For extra security a passcode can be added. To make installation simple, Access Irrigation also produce valve box kits which include a valve box and also 2 or 4 irrigation valves. These are designed to be buried in the garden, with an underground supply pipe bringing water to the valve box and then undergroung pipes going from the control valves to the variour areas to be watered. In 'Home Gardens' a DB valve kit is available to comply with the Water Regulations; this connects via the master valve of the controller. For very simple systems, Access also produce a Bluetooth tap timer, which can be operated from an app.

  • Hunter MP rotator sprinklers provide flexible watering for small lawns. One of the problems with rotor sprinklers is that if the arc is halved, the precipitation rate is effectively doubled. This leads to very uneven watering. In contrast the MP (matched precipitation) nozzles ensure that if the arc is reduced, so is the flow of water. With complex lawn shapes the ability to mix different arcs on the same zone and not have to worry about differences in precipitation is a game changer for the industry. Hunter MP Rotator Sprinklers With the MP Rotator range there are a number of different sprinkler heads. Three main ranges are the MP1000, MP2000 and MP3000. The MP1000 range has 4 different arc combinations, the smallest covering 45-105 degrees and the largest a 360 degree full circle. The MP1000 sprinkler covers 2.6m -3.5m radius. The MP2000 range covers 4.9m - 6.4m and the MP3000 range covers 7.6m - 9.1m.  Hunter Industries have recently launched a new short radius nozzle and also a longer range nozzle which will cover up to 10.7m radius. The short radius 800 series are designed for lawn coverage of between 2.6m and 3.0m, making them ideal of UK sized domestic gardens. There are two nozzles in the MP800 range, the Orange/Grey nozzle will cover arcs from 90 degrees to 210 degrees, and the Lime Green will cover a full circle. Both nozzles will operate at pressures between 1.7 bar and 3.8 bar. At the top end of the range the MP3500 sprinkler will cover a radius between 9.4m and 10.7m. At present only one colour is available, the Light Brown option which will cover an arc between 90 degrees and 270 degrees. With an output of 900 l/h a very good mains pressure and flow are needed, or the sprinkler needs to operate from a pump and storage tank. Hunter MP Rotator Sprinkler bodies Two MP rotator sprinkler body types are offered. The unregulated body allows the pressure to be varied. With the MP rotator system, when the pressure changes the radius of the sprinkler also varies. Hunter are also offering a new 'Pro' body. This features a heavier duty spring and a 5 year warranty. It also features a check valve, which is ideal for sites with changes in elevation. With the Pro body, the sprinkler output is regulated to 2.8 bar. Operating Hunter MP Rotators in Domestic Gardens Hunter MP rotator sprinklers are generally operated at 2.8 bar pressure, which is high for a private domestic garden. To ensure an adequate pressure and flow is provided, a pump and tank unit is recommended. The pump and tank also provides compliance with UK Water Regulations for domestic gardens. A 500 litre tank with submersible pump can be delivered on a pallet for easy installation and will provide enough flow to water a typical irrigation system in a domestic garden.

  • Causes of Water Hammer Like any other moving fluid, flowing water has momentum.  When subjected to a sudden change in flow, shock waves propagate through the system.  This occurrence is referred to as ‘water hammer’.  Flow changes can occur due to the operation of valves, the starting and stopping of pumps, or directional changes caused by pipe fittings.  Other causes may be the rapid exhaustion of all air from the system or the recombination of water after water column separation. When sudden changes in flow occur, the energy associated with the flowing water is suddenly transformed into pressure at that location.  This excess pressure is known as surge pressure and is greater with large changes in velocity. Water hammer is usually caused in high pressure (e.g. mains pressure) water systems either when a tap is turned off quickly, or by fast-acting solenoid valves, which suddenly stop the water moving through the pipes and sets up a shock wave through the water, causing the pipes to vibrate and ‘shudder’. Water hammer will be made worse by having worn valves and pipework inadequately supported. There are five probable areas to look at for the cause of water hammer and a number of possible cures - the appropriate cure will depend upon the actual cause and the installation.  If the water hammer only started after some work was done on the plumbing system, start by looking at those areas; however, any change to a plumbing system may start water hammer in another area. Probable Sources of Water Hammer Inadequately secured pipework – more likely to cause water hammer after new work has been done; if water hammer first occurs without new work having been done, check the other possible cures first. Ball and float valves. Fast acting valves. Worn stop valves. Trapped air. Unsecured Pipework Ensure that pipework is clipped, secured and supported at regular intervals using pipe clips of the appropriate size. Ball /Float Valves Water hammer can result from ripples inside open water tanks where the water level is controlled by a ball/float valve – the ripples being caused by the inflow of water with the result that the valve float ‘bobs’ up and down thus repeatedly opening and closing the valve.  This repeated opening and closing of the valve sets up shock waves which reverberate along the pipework causing the water hammer effect. If the water tank is plastic, a metal reinforcing plate fitted on the side of the tank where the float valve is installed will reduce the flexing of the tank. Other than the above, ripples in the water will usually only cause problems if the ball/float valve is worn or if the valve has a low pressure valve nozzle fitted when the water supply is high pressure.  Ensure that the washers and diaphragms in ball/float valves are not worn and that the appropriate valve nozzle is fitted.  The latter should not be the problem if the water hammer started some time after the valve was fitted. On small tanks, fitting a Torbeck cistern valve is another possible cure as it will prevent ripples on the water surface, so the valve will close cleanly. Solenoid Valves Some electrically operated solenoid valves stop the flow of water instantaneously, so possibly setting up the shock wave through the pipework to cause the water hammer.  Flexible hose attaching the valve to the water supply may be enough to absorb any shock in the pipework. Stop Valve Stop valves (stopcocks) and taps can cause water hammer if they have loose gland packing and/or worn washer jumpers.  Stop valves will generally be open when the water hammer shock wave travels through the pipework and the shock wave could well ‘rattle’ the valve handle and a loose jumper. While it is possible to tighten the gland packing and replace a loose jumper, the easiest way to cure the problem is to replace the stop valve. Trapped Air Problems associated with air entrapment can be minimized by preventing air from accumulating in the system.  This can be accomplished by using air-relief valves positioned at the high points of the piping system.  In areas of relatively flat terrain these should also be used in the vicinity of the pump discharge, near the middle of the line, and at the downstream end of the line. Empty pipelines should be filled as slowly as possible to allow entrapped air to escape. Other Considerations All pipework should be sized so that the flow velocity is not more than 1.5m/s. Surge arrestors (relatively simple devices such as small pressure tanks or buffer vessels, which can absorb shock waves) can be installed at strategic positions in the pipeline to minimize the effects of water hammer in the system.  Surge arrestors should be installed as close to the source of the problem as possible.

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