Contents. Dŵr Cymru Welsh Water. How Welsh Water is managed. How water resources are managed. How water is treated and distributed

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2 Contents About Dŵr Cymru Welsh Water How Welsh Water is managed How water resources are managed How water is treated and distributed How wastewater/sewage is managed Water and the customer Water in Wales Health and Safety at Dŵr Cymru Welsh Water

3 Key facts about Dŵr Cymru welsh water number of household customers water 1,300,000 number of household customers wastewater 1,250,000 number of business customers water 110,000 number of business customers wastewater 76,000 average amount of water produced every day (megalitres) 840 length of water mains (km) 27,400 length of sewers (km) 19,000 number of water treatment works 68 number of sewage treatment works 833 number of water pumping stations 714 number of sewage pumping stations 1861 number of combined sewage outfalls 3,200 number of impounding reservoirs 65 number of service reservoirs 654 1

4 1 about Dŵr Cymru welsh water Dŵr Cymru Welsh Water is a regulated not for profit company, that provides water supply and sewerage services to more than three million people living and working in Wales and some adjoining areas of England. as with all other UK water companies, welsh water s spending and maximum customer bill levels are determined by industry regulator Ofwat. Other regulators include the welsh assembly Government, the Drinking water inspectorate and the environment agency. The company has 1.3 million household customers and over 100,000 business customers, making it the sixth largest of the 23 water companies in england and wales. it may seem that providing water to people s homes is a simple matter as it only involves capturing the rain and piping it to homes. But in reality the water industry is much more complex. To ensure a constant supply of water, man has created his own water cycle by tapping into the natural one. welsh water takes water from rivers, lakes and boreholes. it is then cleaned and treated before being delivered to its 3 million customers. welsh water has two key responsibilities: to provide a high quality water supply to customers and to take away wastewater and return it to the environment safely. These functions require billions of pounds of equipment and other assets, and cost hundreds of millions of pounds to operate each year. To replace all of welsh water s assets at today s prices would cost 25 billion. To provide a water supply, welsh water has 65 impounding reservoirs that is, water storage areas mainly created by building dams across river valleys in upland areas. The company has 68 water treatment works, where reservoir water is treated so it can be drunk from the tap, and it supplies an average of 840 million litres of water every day through a network of 27,400 km of water mains. as many reservoirs and water treatment works are on high ground, gravity helps supply much of the water our customers consume. This means less energy is needed to pump water around the system and this benefits the environment by reducing the company s carbon footprint. Taking away wastewater from customers homes and businesses from sinks, baths, toilets and industrial activities - is also a major task. we collect this wastewater together with rainwater that runs into drains from roadways, roofs and other surfaces and it is all carried through a network of 19,000 km of sewers. The wastewater is treated to make it biologically safe at 833 wastewater treatment works located next to rivers and along the coast of wales. 2

5 2 How welsh water is managed Welsh Water is not like other UK water and sewerage companies in the way it is operated, as it is not run to make a profit. it is owned by Glas Cymru and has no shareholders. its only purpose is to deliver the best possible service to customers at a fair price. if welsh water makes a financial surplus then it is reinvested for better services. welsh water also differs from other water companies in that it employs relatively few people. instead it outsources key functions such as maintaining its equipment, building new assets and providing customer services, to other companies that are expert in each of these activities. in this way welsh water aims to get the best service for its customers. welsh water and its partner companies work together in what is called the asset Management alliance. 3

6 3 How water resources are managed The water cycle The earth has a finite amount of water, which is naturally circulated in what is called the "water Cycle". This cycle starts with evaporation of water from seas, lakes and rivers and transpiration from plants. The evaporated water condenses and falls as rain. The rainwater collects in streams and rivers that starts the process over again. after use, the dirty wastewater or sewage is taken away, cleaned and returned to the natural cycle. it is an amazing fact that 99% of the world s water is unavailable for us to use. 97% is saltwater in the oceans and the seas and 2% is frozen in the polar ice caps, leaving only 1% as fresh water for us to use which is the equivalent of only ten days rainfall! Water supply sources of drinking water have changed little over the centuries. it is still drawn from springs, rivers and lakes, all of which are replenished by rainfall. This process of taking water from the environment is called abstraction. in many cases, the natural water supply is insufficient to meet demands of the community particularly in densely populated areas. To overcome this deficiency, dams are built to create reservoirs. also, major transfer schemes are used to move water from areas where there is a surplus, to others where there may be a shortfall. For example, the large city of Birmingham is supplied from the elan Valley reservoirs of Mid wales. 4

7 The area served by welsh water receives more rain overall than most other parts of the UK. The wettest area is snowdonia with up to 6000mm rainfall a year. The driest is Herefordshire with an average of only 700mm. although there is a generous supply of rain in wales, the demand for water from customers increases every year. This requires careful management of resources at every stage if the company is to ensure a high quality, constant supply of fresh, clean water. so to satisfy the ever increasing demands of customers, welsh water is constantly investing in, improving and extending its water supply network. Water in Wales The region s high annual rainfall and natural geographical features of hills and valleys favour the catchment and storage of water. Of welsh water s water supplies: 97% comes from surface water 3% comes from ground water 5

8 River flow Various factors affect the surface drainage pattern and extent of river flow within a particular region. These combine to determine the ways in which water resources are managed. Climate amount of precipitation received, evaporation and transpiration (evaporation of water from plants) rates. Catchment size and shape of catchment area. Slope the steeper the degree of slope the greater the run-off into streams and rivers. Valley form glaciated, U-shaped valleys hold more water and reduce evaporation losses. Geology permeable rocks such as chalk allow water to percolate through to the water table below. Soil & Vegetation thin soil and sparse ground cover over impervious rocks greatly increase surface run-off and therefore river flow. Conversely, thick soil and extensive vegetation will transpire water and reduce the volume of run-off. Farming grazing animals deplete the natural vegetation which increases surface water runoff. arable farming needs a reliable supply of water and often involves irrigation or drainage schemes which take water from rivers and reduce flow. Urban Development tarmac and concrete surfaces greatly increase run-off rates. if treated wastewater is pumped back into a river, flow is increased from that point. 6

9 4 How water is treated and distributed Water quality By the time it reaches rivers, reservoirs or aquifers, water already contains a wide variety of substances which determine its quality. it absorbs dirt, dust and gases from the air, debris and bacteria from the ground, and soluble minerals from rocks. at a water treatment works the main objective is to destroy the bacteria and remove as many unwanted substances as possible. although water treatment techniques vary widely depending on local factors, the end result will always be water that complies with the current drinking water directives. However, its character will vary greatly from one area to another. in Britain today people take access to a regular, reliable and safe supply of pure water very much for granted. water from our taps is expected to be safe, clean and pleasant to drink. water is a natural resource, but it has to be purified before you can drink it. The water you see in the reservoirs is raw water in its natural state. The water needs to be cleaned and treated at the treatment works to a high quality, and delivered 24 hours a day, 365 days a year. This requires a high degree of engineering and scientific skill. Clean water The natural water we see around us almost everywhere often appears to be clean but this is rarely the case. water has the ability to accommodate a huge range of substances which can make the water unsafe to drink without any change in its appearance. natural waters are a mixture of chemicals, microorganisms, and suspended material. The exact composition of water varies from one area to another and even from day to day. water sources throughout wales can vary in it s make up dependent on its source and the surrounding geography. 7

10 Above: Clarification process. Above: Clarification, removal of clumps from clearer water (Floccuation tanks). Above: Filtration, Stage 1. TO SLUDGE THICKENING PLANT RETURN TO WASH WATER RECOVERY TANKS SLUDGE TO SLUDGE DRYING LAGOONS SLUDGE FROM WASH WATER RECOVERY PLANT DIRTY WASH WATER FROM GRAVITY FILTERS SLUDGE PUMP HOUSE TO SLUDGE PUMP HOUSE WATER OVERFLOW FROM SLUDGE THICKENING PLANT POLYELECTROLYTE Polyelectrolyte is dosed and mixed to help the wash water separate into clean water for recycling and sludge for disposal AFTER SETTLEMENT CYCLE, CLEAN WATER IS RETURNED TO RAW WATER CONTACT TANK FOR REPROCESSING Cleaning water as the quality of water received by water treatment works varies according to where it has come from, the amount of treatment it receives must also vary. water from underground is usually the purest form of natural water having been filtered though rocks and soil. Often, all it needs is disinfection to kill harmful bacteria. water from lakes and reservoirs requires additional treatment and often a series of processes to remove or destroy any unwanted substance. The water abstracted from rivers can be the most variable in quality and usually needs the most treatment. This includes screening, clarification, filtration and disinfection. Methods of treatment Screening this is the first step in the treatment process where mechanical screens remove some of the larger debris that can be found in rivers and reservoirs ie floating material such as branches, twigs, leaves etc. Clarification a treatment chemical (coagulant) is added to the water which causes smaller particles that remain from the screening process to cling together. This process is called coagulation. These particles build into larger clumps which then are easier 8

11 Above: PH Adjustment. Above: Disinfection, chlorine. TO GRAVITY FILTERS WASTE WATER SUPERNATENT RETURN MANGANESE REMOVAL BALANCING TANKS BALANCING TANKS By addition of Chlorine and Lime NORMAL OPERATION WATER LEVEL RECYCLED WATER FROM WASH WATER RECOVERY TANKS FROM COCODAFF PLANT FROM COCODAFF PLANT VIA MANGANESE REMOVAL STAGE 150mm GRANULAR ACTIVATED CARBON 280mm ANTHRACITE 425mm SILICA SAND 75mm FINE GRAVEL ( mm) 75mm COARSE GRAVEL ( mm) TO FILTERED WATER CONTACT TANKS to remove by allowing them to settle and fall to the bottom of the tank leaving cleaner water above. Filtration this is in effect an attempt to recreate nature s own purification process. The water is percolated down through a series of filters made up of a layer of fine sand and supported on layers of coarse sand and gravel. as the water passes through the filters, any remaining material is retained and the clear, filtered water is collected at the bottom. The filters are regularly cleaned and the resulting sludge which has collected is removed for disposal. ph adjustment sometimes it may be necessary to add chemicals to adjust the ph of the water. Chemicals are added to correct the ph value and maintain consistent quality. Disinfection finally, the water must be disinfected to kill any remaining bacteria. This is usually done by adding chlorine or sodium hypochlorite and occasionally ozone. NORMAL OPERATION WATER LEVEL Quality control DIRTY WATER TO WASH WATER RECOVERY TANKS FOR RECYCLING AIR SCOUR 150mm GRANULAR ACTIVATED CARBON 280mm ANTHRACITE 425mm SILICA SAND 75mm FINE GRAVEL ( mm) 75mm COARSE GRAVEL ( mm) FROM WASHWATER TANKS Before drinking water reaches the tap, every drop is cleaned and purified. To make sure it is wholesome and fit to drink, detailed laboratory tests are carried out at different points in the water supply system, including customer s taps. water obtained from upland sources contains

12 naturally occurring iron and manganese which may cause discoloured water. Old water pipes, often made of iron, can add to the problem. all of these are measured prior to and during the treatment process to ensure their removal. The quality of treated water is constantly monitored welsh water analyses more than 60,000 samples every year. Service reservoirs The cleaned water is then stored in totally enclosed tanks made of concrete, metal or fibreglass called service reservoirs, before being piped to customers. These reservoirs also ensure a supply to the customer s taps during periods of peak demand and maintain pressure within the system. Water distribution systems Delivering great volumes of water to virtually every domestic, agricultural and industrial premises in the land requires a vast network of pipes and mains. Much of the network in welsh water s region covers rural areas with small populations where it is much more costly to supply each resident than in high density urban areas. Maintaining a water supply network presents many problems. as the mains are underground, detecting fractures or cracks is not easy and even when minor leaks are detected it is very expensive to dig up the ground to repair them. water from the service reservoir (where treated water is stored) passes through pipes, usually by gravity flow, until it reaches the customer. in some areas it is necessary to build tall water towers to maintain pressure. it is this pressure that makes water pour out of the tap when it is turned on. water mains have to be designed and constructed to withstand this pressure. Many different materials have been used in the past, but today mains tend to be made of ductile iron or PVC, depending on the nature of the ground. Ductile iron is very strong and can resist ground movement, but plastic is more resistant to corrosion. 1

13 5 How wastewater/sewage is managed What is wastewater/sewage? we tend to think of sewage as the water poured down the drain after washing dishes, taking a bath or flushing the toilet. in fact, wastewater includes all waste water. This contains a variety of substances, some dissolved and some in the form of solids which will float, sink or stay suspended in the water. Domestic water from baths, washing up, toilets etc. industrial waste water that may contain animal and human waste, oils, sand and sometimes harmful chemicals. Rainwater that runs off roofs, roads and pavements. Wastewater collection Collecting this enormous amount of wastewater and getting it to a treatment works is a major engineering task requiring a vast network of sewers spreading out to virtually every home, office, shop, school and factory in the country. in the region covered by welsh water, this amounts to approximately 19,000km of pipes and drains. This network has been developed over many years and in some parts of Britain the sewers in use today were designed and built during the 19th century. Many of them are in a poor state of repair and badly need replacing. Carrying out maintenance work on such a large underground network is both difficult and costly. apart from deterioration through normal wear and tear, sewers can be damaged by the weight of traffic moving above them, by ground movement or subsidence in the soil. a major break in a foul water sewer can lead to serious problems. it is therefore essential that the sewage network works efficiently and is maintained to the highest possible standard. Sewage network types There are two main types of sewage network: Combined sewers single pipes which carry both domestic and industrial foul water as well as surface rainwater. Separate sewers one pipe that carries foul water and another pipe that carries rainwater run-off. wherever possible, separate sewers are preferred because rainwater and foul water can be kept apart and in storm conditions rainwater can be easily discharged directly to rivers or the sea. (for more info see page 16) Industrial effluent The quality of domestic sewage is fairly predictable and unlikely to contain any highly toxic substances. industrial effluent however varies greatly and companies need consent before any discharge into public sewers can take place. The sewerage company needs to be sure that the effluent: is safe and will not be a health risk to service engineers will not damage either the fabric of the pipes and sewers or the equipment at the sewage treatment works, and Has been sufficiently treated before discharge to remove any toxic substances. 11

14 Above: Inlet and grit removal. Above: First stage - primary settlement. Above: Activated sludge. Screening conveyor Raw sewage from inlet chamber Travelling bridge Grease removal Grease skimmed from the surface into the channel From screening plant Grease to grease To concentrator primary treatment From primary lamella tanks To secondary settlement tanks Screen brush Screenings removed to macerator tank Screened water forwarded for grit and grease removal Grit removal Grit pumped to grit classifiers Grit settles to base of the tank and is scraped to the grit pumps Turbine aerators to float grease to the surface Compressed air pumped to the diffusers Fine bubble air duffusers Wastewater treatment The purpose of wastewater treatment is to remove enough impurities from the wastewater to enable it to be returned safely to a river or the sea where it can again become part of the natural water cycle. wastewater treatment is a complex process and methods used vary within the company s areas. However, the key processes are as follows: Screening metal screens remove large, floating objects such as paper, wood, cans and plastics which could block pipes or damage equipment. Grit channels wastewater flows slowly along wide channels allowing grit and heavy particles to fall to the bottom. Settling tanks fine, solid particles settle out of the sewage, falling to the bottom of the tank to form sludge. This process is called sedimentation. Biological filters partly treated wastewater is spread over large beds of rough stones or clinker where colonies of bacteria have formed. The bacteria remove harmful waste by feeding on organic matter in the sewage converting it to carbon dioxide, water and nitrogen compounds. This biological activity produces a liquid containing humus particles which then settle out in special tanks. 12

15 Above: Final settlement tanks. Above: Sludge storage. Water Spray Plastic Media Filter Plenum Water Chemical Dosing From aeration tanks Water To Secomam Unit To ultra violet disinfection Lamella plates Sludge settles to base of hopper-bottomed tanks Activated sludge this is an alternative to biological filtration where a culture of bacteria (activated sludge) feeds on the sewage. The air the bacteria need is pumped in under pressure by surface aerators and fine bubble diffusers. Final settling tanks even after final sedimentation the cleaned water, or effluent, still contains organic material. if this is discharged into a river with low natural flow pollution could occur. also, the water may not be clean enough to be safely abstracted downstream. in these cases polishing treatments such as pebble bed clarifiers, sand filtration and micro-straining are used. The treated effluent then flows over weirs to rivers and streams where it rejoins the natural water cycle. To raw sludge holding tank From secondary lamella tanks 160 medium pressure ultra violet lamps in two banks of 80 Monitoring as technology creates new, more advanced materials and substances such as chemical compounds or even biological washing powders, water services companies and the environment agency need to match these developments with sophisticated monitoring techniques to ensure thorough and safe wastewater treatment for their customers. Treated clean water to sea outfall 13

16 Wastewater disposal when people have finished using water, it is expected that the wastewater produced will be taken away and cleaned up properly before it is put back into rivers and the sea. However, the more water people use, the more wastewater is created and as environmental protection becomes increasingly important, traditional methods of disposing of wastewater come under close scrutiny. Sewers welsh water s network of sewers takes away the wastewater produced by households and businesses as well as the rainwater that runs off roofs and streets into drains. Much of the network is old, often dating back to Victorian times and some sewers are too small to cope with the sheer volume of today s wastewater. as our climate is changing sometimes flooding occurs when there is heavy rain or flash floods. Surface Water surface water is the rainwater that runs from roofs, highways and paved areas into the public sewerage system. For a number of reasons, including more frequent storms and the growth of built up areas, welsh water s sewer network has to deal with increasing flows of surface water. Occasionally, the capacity of the network is exceeded in some areas and results in incidents of sewage flooding of homes, gardens and roadways and can cause pollution incidents in streams and rivers. Storm overflows There are 3,200 storm overflows on welsh water s sewerage system. These are structures on a sewer designed to discharge excess surface water directly into rivers during periods of heavy rainfall to avoid flooding roads and properties. River discharge welsh water has 833 sewage treatment works across its region, most of which are located inland next to towns and villages and discharge into local rivers or the sea. all the inland works use biological processes to clean the waste water collected from customers so that it can be safely returned to local rivers. environment agency wales sets clear, well defined standards to protect the river environment and then monitors the performance of welsh water s sewage works, the company s pass rate is routinely between 99% and 100%. 14

17 6 water and the customer Each person in Britain uses an average of 150 litres of water a day - about 15 bucketfuls. Our great grandparents would have managed with about 18 litres or two bucketfuls! Water in the home and garden in recent years domestic consumption of water has increased dramatically, and as living standards rise and more people buy washing machines, dishwashers, hot-tubs and even swimming pools, so the demand for water increases. The average household uses 420 litres of water every single day. The largest domestic use is for flushing toilets followed by baths, showers and washing machines. although all this water has to be treated to a standard that makes it fit to drink; only 1% is actually used for drinking purposes. The rest is used for a wide variety of other activities in and around the home. Welsh Water customer campaigns welsh water is keen to involve its customers in understanding how their behaviour affects the water and wastewater network in their area, and has a number of customer campaigns designed to draw attention to customers activities and how they impact on the performance of its systems. also, welsh water is rising to the challenges that climate change is bringing to the water industry. with more long, hot and dry summers predicted, together with more frequent and intense winter storms, welsh water is asking its customers to look at how small changes in their everyday lives can help to combat the effects of climate change. Be Waterwise water efficiency The Be waterwise campaign was launched in March 2007 and is designed to inform customers that whilst they can use all the drinking water they need, water, even in wales, is a finite resource and wasting it is bad for the environment. Our message Use as much drinking water as you need but please don t waste it Using water wisely is one of the everyday activities we can all do to help manage the effects of climate change. 13% 9% 16% 4% 3% 22% 33% wales is not immune from the threat of future water shortages and we can all play an important part in conserving resources. it is in everyone s interest to avoid wasting water and advice is being made available on how to achieve this in the home and garden. water efficiency tips include having a shower instead of a bath, and not leaving the tap running when washing hands or brushing teeth. The biggest user of water in the home is garden sprinklers, using as much water in an hour as an average family will use over two days - use a watering can or handheld device instead. How your water is used in the home 33% flushing the toilet 22% using the washing machine and dishwasher 16% using the kitchen sink 13% taking a bath 9% using a handbasin 4% taking a shower 3% using the outside tap 15

18 Green Space Wales surface water run-off welsh water s Green space wales campaign is focused on the management of surface water run- off to prevent flooding and pollution by maintaining as much Green space as possible. Climate change is predicted to bring more heavy rainfall on an increasingly developed urban landscape of roads, car parks, buildings and paved front gardens. with reduced green areas for drainage, rainfall is increasingly channelled into public sewers, sometimes overloading them and causing sewer flooding and pollution incidents. The company is asking people to consider the following practical examples of things that will help, such as using porous paving or gravel for new or altered paths, driveways or patios, so instead of rainwater running off, it soaks through to the ground underneath. also, if people are building an extension to their house or a complete new build, the layout can be designed so that it allows drainpipes to run straight into the garden to water plants directly. The company is also encouraging people to use water butts which can be attached to drainpipes. This water can be stored and used to water the garden, and stops the water going into the sewer. Drains awareness Wales keep FOG out of the sewers welsh water s Drains awareness wales campaign aims to prevent the build up of fats, oils and grease (FOG) in sewers across wales, by discouraging customers from pouring them down the sink. Coagulated FOG builds up in sewers, causing blockages which can result in flooding pollution, and overflowing drains, sinks and toilets. This can be an expensive problem not only for welsh water, but also for householders if they have a blockage on their own system and need to call out a plumber to clear it. in the UK there are approximately 200,000 sewer blockages, and 75% of these are caused by fats, oils and grease disposed of into the sewer system. welsh water encourages customers to stop and think. not down the sink! instead offering customers tips on how to dispose of FOG correctly, including collecting FOG in a container to dispose of with the refuse. Or, make fat balls or bird cakes to feed the birds and scrape plates into the bin or food collection containers provided by the local authority and not wash it down the sink. Pouring boiling water down the sink to flush away FOG does not work! 16

19 The Dirty Dozen don t use toilets as bins welsh water is asking its customers not to use toilets as bins, and is drawing attention to the Dirty Dozen items that cause most problems when they are flushed down the toilet, instead of being disposed of with the household waste. Flushing inappropriate objects causes thousands of blocked sewers every year, sometimes resulting in pollution of water courses and sewage flooding of homes. even small items that are flushed away can build up and cause obstructions, or pass through sewage works and end up as litter on beaches and river banks. For more information visit our website on WaterAid in Wales welsh water and its alliance partners are fully committed to supporting national charity wateraid s aim to use practical solutions to provide safe water, effective sanitation and hygiene education to the world s poorest people. wateraid also seeks to influence policy at national and international levels. welsh water re-launched wateraid in wales on world water Day (22nd March) 2004 and set the ambitious target of raising 1 million in ten years. a wide range of large and small fundraising activities are organised every year and fundraising is on track to achieving its ambitious target. Education and Welsh Water welsh water is keen to provide a hands on learning experience for its future customers. since the launch of the education strategy, over 100,000 pupils have visited one of its 4 award winning education centres. Teachers are seconded into the business on a professional development opportunity to deliver key business messages on the vital role of water. Pupils are able to experience first hand how the water is cleaned at the treatment works. They can also discover how the climate is changing and how this is affecting the water cycle along with river study lessons, water efficiency and many other exciting practical outdoor lessons. all lessons are linked to the national Curriculum and fully risk assessed. Paying for water services Rainwater may be free but water from the tap is certainly not and customers have to pay for their supplies. industrial users have a meter to measure the amount they use. new homes must have a water meter, and other domestic customers can also choose to have a water meter installed free by their water services company, but most householders choose to pay for an unmeasured supply of water at the standard annual rates. 17

20 7 water in wales Welsh Water provides most of Wales and some bordering areas of England with water and sewerage services, supplying customers with clean, safe drinking water and taking away wastewater 24 hours a day, 365 days a year. Location of Welsh Water assets welsh water sites are found all over wales. its reservoirs are generally located on high ground. Rainfall is higher and the water can then be gravity fed to the treatment works and on to the settlements where water is used. welsh water s water treatment works are also generally located on higher ground and near to reservoirs. This also means that it is possible to take advantage of gravity to move water and minimise the company s use of electricity and consequently reduce the environmental impact and its carbon footprint. wastewater treatment works are located near to settlements where much of the wastewater is produced. welsh water has 10 times as many wastewater treatment works as it does water treatment works. This is because it is not possible to take advantage of gravity to move wastewater to the treatment works from people s houses and it would not be efficient to pump wastewater great distances. There is also more wastewater to treat because of the surface water (or rainwater) going down the drains from roofs, roads and driveways. 18

21 water Treatment works Holyhead Bangor Pwllheli Llyn Alaw Cwmstradllyn Llandudno Rhyl Denbigh Mold Conwy Alwen Celyn Alwen Llyn Brenig Chester Dee Wrexham 1-10 Ml/d Ml/d Ml/d > 100 Ml/d 14 largest reservoirs Machynlleth Dolgellau Severn Water boundary Wastewater boundary Aberystwyth Elan Llandrindod Wells Llyn Brianne Wye Llys-y-Frân Fishguard E Cleddau Haverfordwest Tenby Carmarthen Llanelli Lampeter Swansea Tywi Usk Crai Pontypridd Brecon Llwynon Pontsticill Talybont Usk Hereford Monmouth Chepstow Llandegfedd Newport Bridgend 1

22 Conwy wastewater Treatment works Holyhead Llandudno Rhyl Bangor Denbigh Mold Chester Pwllheli Alwen Dee Wrexham Population ,000 2,000-10,000 10,000-25,000 25,000 + Water boundary Wastewater boundary Machynlleth Aberystwyth Dolgellau Severn Llandrindod Wells Wye Fishguard Lampeter Tywi Usk Brecon Hereford E Cleddau Haverfordwest Tenby Carmarthen Llanelli Swansea Pontypridd Monmouth Chepstow Bridgend Newport 2

23 8 Health and safety at Dŵr Cymru welsh water Welsh Water believes that everyone who works on its behalf, or is affected by its undertaking, has the fundamental right to return home safely at the end of each day and that there is nothing more important than the health and safety of the company s employees, customers, partners, contractors, neighbours and members of the public. The company aims to create a positive health and safety culture in which everyone believes that health and safety is an integral part of the way welsh water manages its business, and understands and accepts their responsibilities and actively seeks to minimise the risk to themselves, and to those who may be affected by the company s undertaking. Hazard and risk a hazard is any source or situation with a potential for harm in terms of human injury or ill health, damage to property, damage to the workplace environment, or a combination thereof. a risk is the combination of the likelihood and consequence(s) of a specified hazardous event occurring. People face hazards and risks everyday, (crossing the road for example) and make their own judgement on the potential risks in this situation. However, in the workplace businesses have to make a formal judgement on whether any significant level of risk is acceptable as part of its work. at welsh water we do this through a formal process of risk assessment. This process is quite simple, it involves: looking for hazards in a task identifying anyone or anything that may be harmed or damaged Deciding how likely and how serious the harm or damage will be Deciding the best ways to reduce the likelihood and severity of the harm or damage. This is often achieved by adopting safe working practices. 21

24 Contact For further information please contact: Cilfynydd Environmental Education Centre, Cilfynydd Waste Water Treatment Works Cilfynydd, Rhondda Cynon Taff, CF37 4WX. Telephone: Fax: web: 22