Frequently Asked Questions

Marshall Pump Systems Ltd has a proven track record in water treatment, built up over many years of specialist experience.  No one has better resource, back up or technical knowledge in this field than our CleanStream Department.  Continually liaising with Water Authorities, University Research Departments and The Environmental Health Departments we are ideally placed to solve your water problems and provide you and your family with clean, safe, water.

The new Private Water Supplies Regulations 2009 came into force on the 1st January 2010, the revised regulations are an update of the 1991 regulations and one of the most significant changes is that they not only rely on water samples but they also include and put great emphasis on the source of water and supply chain being subject to a risk assessment.

The inclusion of a risk assessment is a ‘step change’ in the management of private water supplies, previously a sample of water was taken and that result formed the basis of the treatment process, unfortunately the quality of water from a private water supply is at the effect of the prevailing weather and the immediate environment; so a single water analysis is only a ‘snapshot’ of the water quality at that moment in time and not representative of the variation in the water quality, or the risks that it represents.

The inclusion of a risk assessment is more comprehensive approach to quantify the potential risks a particular water source poses, the assessment begins at the source of the water and includes any intermediate processes, i.e. storage tanks, through to the point of use, it will also consider the risk of contamination from external sources such as fuel, chemical and septic tanks, agricultural and commercial activity, and allows a sensible approach to the deal with the risks these may pose.

General Water Quality

What is Ecoli?
Why must I have this treatment installed? I have never had a days illness and my granny lived to be 94years old.
Why have they never found any bacteria before?
Why does the hot water tank leak and have green spots?
Why does the soap go blue or green?
Why does my wife’s blonde hair turn green?
Why have I got blue/green stains on all the sanitary fittings?
My old hot water cylinder lasted for years , why has the new one only lasted a few years.
Has the acid level got worse?
Does treating the water alter the taste?
Can I just treat drinking water? The rest I’m not bothered about!
How big is the U.V.?
How long will the U.V. last?
How much do the lamps cost?
Can I just put in a filter without an ultra-violet unit?
Will I need a pump?

Iron

My supply is a borehole supply. It is high in iron. Can you help?
How big is the filter and how much will it cost?
Where does it go?
How long does an iron removal filter last?
The water is clear but often the hot tap is very dirty or the water is dirty sometimes. Why?
How is the filter cleaned?
Will the filter treat other problems?

Nitrates

What about nitrates?
What systems are available?
Which system is best?

General

I have had other quotes and your system seems expensive. Why is that?
How often does the filter require servicing?
If I put in a sediment filter, how long will it last?
The water gravity feeds from the stream into a tank. Where does the equipment fit?
If I don’t have an analysis. Where can I get one?
Can the equipment be installed in the house?
How much will a service cost?
Do I need a U.V. on the borehole supply?
There is a smell of bad eggs in the water. What is it and can you cure it?

General Water Quality

Q. What is Ecoli? top of page

A. A bacteria living in the intestines of man and animals. When testing the water supplies it is very easy to test for bacteria and is an indicator that other more harmful pathogens are present. The harmful ones such as E0157 are more difficult and expensive to test for.

Q. Why must I have this treatment installed? I have never had a days illness and my granny lived to be 94 years old. top of page

A. You have probably built up immunity to the bacteria present and the occasional upset caused by virulent bacteria was probably put down to a ‘bad pint of beer’. People visiting your house would not be immune and could be more susceptible to any bacteria. If you are in food preparation or catering in any way to the public you should have treatment plant installed.

Q. Why have they never found any bacteria before? top of page

A. Weather has a lot of influence on both chemicals and bacteria analysis. Recent surveys show that most surface water supplies fail if the tests are carried out within 3 days of rain and may pass within dry periods. Contamination is often the result of bacteria in animal droppings. They thrive in a nice warm intestine, fed three times a day and multiply rapidly. Once excreted into the hostile world, they have a limited life, usually up to 3 days. If it does not rain then the droppings and hence the bacteria don’t get washed in. Also, they tend to ‘clump’ together in the water so your analysis is really a ‘snapshot’ of the water at a particular time, and cannot be used as an exact interpretation. Also, specific pathogens such as Cryptosporidium & Giardia do not show up on the test methods.

Q. Why does the hot water tank leak and have green spots?
Why does the soap go blue or green?
Why does my wife’s blonde hair turn green?
Why have I got blue/green stains on all the sanitary fittings?top of page

A. All these are an indication of low pH or ‘acid water’. The rain in the U.K. often has a pH valve or hydrogen ion value of between 5 and 6. It is therefore aggressive to metals. Dependent on the type of land it flows over the acid level can be increased i.e. the pH lowered. It therefore corrodes any metals it comes into contact with. In your property the copper is dissolved, particularly the ‘hot acid’ in your hot water cylinder. The copper reacts with soaps and dyes causing the discolouration you see. In extreme cases it reacts with blonde dyes resulting in unusual hair colour. If this happened with your wife she may not be a natural blonde!

Q. My old hot water cylinder lasted for years but the new one only a few years.
Has the acid level got worse? top of page

A. The answer to this is probably yes. Industrial pollution, particularly sulphur dioxide from power stations has increased resulting in acid rain. In addition, the tanks are now manufactured from much thinner material resulting in quicker penetration by the water.

Q. Does treating the water alter the taste? top of page

A. It depends on the treatment. Using ultra-violet light to destroy bacteria does not affect the taste. It is a physical process, not a chemical process, however the water must be pre-treated. The minimum requirement is a sediment filter to stop particles of dirt shielding bacteria from the U.V. light. Unlike chlorine, which does affect the taste and is a chemical process. Chlorination therefore takes time for the reaction to take place – usually 45 minutes. Ultra-violet is instant and does not require the addition of chemicals. pH correction may cause a slight change in taste if this is fitted. Care is however taken to prevent this or minimise it.

Q. Can I just treat drinking water? The rest I’m not bothered about! top of page

A. No. The regulations are quite clear and sensible. From a bacteria viewpoint all water must be treated. Where children are concerned you never know which tap they will drink from. Another point is if the water is contaminated with sheep droppings, do you really want to shower in it? If you have any open wounds – would you want to bathe them in infected water?

Q. How big is the U.V.? top of page

A. The size is shown in the literature. It is usually 1m in length. It is however the flow-rate which is critical and the energy level. Whilst the lamp should generate enough energy to destroy bacteria, it can only treat a certain rate of flow. Since the ultra-violet unit must be capable of meeting the peak flow demands it must treat sufficient for your needs. Each tap runs at between 6 and 8 litres/minute. The U.V. must therefore be capable of treating generally in excess of one tap and possibly two or more if you take in account other demands. The energy levels are important.

Q. How long will the U.V. last? top of page

A. The basic unit should have a life of many years, although the lamp does degrade with use, a 12-month life is normal. This is longer than some other manufactured units and even at the end of its life, leaves safety margins in levels of disinfection. The CleanStream® system is installed with your health as a priority and as such we carry out full annual services on all equipment.

Q. How much do the lamps cost? top of page

A. They vary but current range is between £20 and £50 depending on wattage. We recommend that you check spare lamp price and availability before you buy a U.V., we’ll be happy to assist in this

Q. Can I just put in a filter without an ultra-violet unit? top of page

A. Not if the supply is a surface water supply. If a filter is fitted it can make matters worse unless a U.V. is fitted. The filter can harbour bacteria and in certain circumstances promote bacterial growth. It is therefore essential the two be integrated carefully. Research on borehole supplies show that over 20% of these are contaminated with bacteria so; again UV should be considered as an option.

Q. Will I need a pump? top of page

A. A U.V. does not cause any significant pressure loss; it will however treat only a certain flow rate. With CleanStream® care is taken to ensure no significant pressure restriction is placed on the system. A sediment filter will cause some restriction dependent on how clean it is. The neutralising filters need more pressure, approximately 20m head. (2 Bar). Often therefore a pump is required but this a relatively low cost part of the system.

Iron

Q. My supply is a borehole supply. It is high in iron. Can you help? top of page

A. Yes. You need an iron removal filter. Firstly however we need some details. What levels of iron are present? Usually this is given in the report from the analyst. The units will be in mg / litre (milligrammes per litre) or µg / litre (microgrammes per litre). The maximum allowable values are 0.2mg/litre.

One mg / litre is one part per million, one µg/litre is one part per 1000 million!!!

Q. How big is the filter and how much will it cost? top of page

A. That depends on the iron levels. Up to 5mg/litre we can use our ‘B’ type filter. Over that the ‘T’ filter is needed. A site visit would be required but costs could be between £900 and £1800 dependent on what we find. As far as size is concerned, it is nearly 6ft (1830mm) tall and looks a bit like an oxyacetylene bottle with a clock on top.

Q. Where does it go? top of page

A. On the raw water supply into your property, typically in a garage or outbuilding, definitely not a loft!

The WaterPac cabinets we supply as an option can accommodate all the equipment necessary they even include a tank. Why not ask for a specific quote?

Q. How long does an iron removal filter last? top of page

A. Indefinitely. The media used to remove iron acts as a catalyst. However, if the water is acidic then an additional media is used in the filter to correct this and will need topping up usually once per year. We can arrange this on our service visit.

Q. The water is clear but often the hot tap is very dirty or the water is dirty sometimes. Why? top of page

A. The iron in the water is in solution and is in the form of ferrous oxide. The filter introduces some air into the water to oxidise the iron to ferric oxide and this is insoluble. It therefore comes out in the filter. Also the pH of the water needs to be around 8.5 to ensure the iron level is low. Thus often there are two media in the filter.

Q. How is the filter cleaned? top of page

A. Automatically, usually twice per week. A timeclock selects a backwash of the filter to clean out the iron sludge and pass it through a ½” pipe to a surface water drain. Usually this is done at night but the clock can be set to clean the filter at other times.

Q. Will the filter treat other problems? top of page

A. Yes. Manganese is often present in irony water or ochre water as it is often referred to. The filter will remove the manganese. Again the process is to form insoluble oxides and hydroxides. Tests have shown that the filter will also deal with a range of metals e.g. aluminium and cadmium but we need to see an analysis to determine the best media.

Nitrates

Q. What about nitrates? top of page

A. Nitrates are removed by a different process, needing an additional filter or filters. With nitrates we need to know both sulphate and chloride levels to advise on a suitable treatment.

Q. What systems are available? top of page

A. Reverse Osmosis and Ion Exchange are the two systems used.

Reverse Osmosis is a very slow method of producing high quality water by removing virtually all impurities in the supply. This type of system produces only a few gallons per day.

Ion Exchange can cope with much higher flow rates and uses a filter media specially designed to remove nitrates from the water. It can almost be considered as a ‘chemical magnet’, which swaps nitrates for chlorides.

Q. Which system is best? top of page

A. Both produce nitrate free water. We would need to discuss your requirements in detail to select the best system to suit your needs. This would all form part of our free water evaluation survey and recommendation.

General

Q. I have had other quotes and your system seems expensive. Why is that? top of page

A. The water treatment equipment available today covers a wide range of products, some good, some bad. Some work and some don’t. The buyer often does not have the ability to make a technical evaluation. Our system is engineered to meet your specific analysis and your house needs. It includes all the necessary isolation and non-return valves to enable servicing to take place. In addition, we fully meet the 1991 Water Regulations. Ask for recommendations and the guarantee from other suppliers and remember, it’s not worth spending money on something you are going to use everyday unless you spend it wisely.

Q. How often does the filter require servicing? top of page

A. We aim for a minimum time between services of 12 months. It will depend however on the water quality and the amount of water used. Some units have been working successfully for up to 4 years without any attention.

Q. If I put in a sediment filter, how long will it last? top of page

A. That depends on how dirty your water gets and how much you use. Remember that with CleanStream® we recommend a site survey (now termed – “Sanitary Survey” in the regulations). This tries to resolve these problems and advise on any preventative measures which can be taken to safeguard your supply. The water supply is an extremely valuable asset to your property. Without a clean and adequate supply your property is worthless. It makes sense to safeguard it.

Q. The water gravity feeds from the stream into a tank. Where does the equipment fit? top of page

A. If the tank is in your loft the U.V. could go on the outlet of the tank but this could present some problems in certain cases. However, care must be taken if the tank is elsewhere e.g. in a barn. There is no point in sterilizing the water to allow a dead bird to contaminate it by falling into an open tank. A long-term view should be taken when deciding on a system. Often it is useful to put the U.V. before the tank, at the point of entry to the house and then tap the drinking water off the rising main.

The addition of a small booster pump is well worth considering giving good cold-water pressure throughout the property. The house can then be plumbed as a mains supply with cold water for drinking and washing off the main feed. This is not often as big a modification as it may first appear and has very major advantages.

In addition, we offer a range of cabinets, which house the equipment outside the house. This allows a pre-built and tested system to be easily fitted at your property.

Q. If I don’t have an analysis. Where can I get one? top of page

A. Your Environmental Health Department will arrange one but will probably charge for it. It may cost anything up to £120. We can however test for pH, iron, manganese, alkalinity and aluminium on our visit to site.

Q. Can the equipment be installed in the house? top of page

A. Yes, but remember you have a large surface area with cold water inside. Condensation can be a problem although the filter can be lagged.

Q. How much will a service cost? top of page

A. Again it will vary with the type of equipment. You should expect a ‘ballpark’ figure of £150.00 - £ 250.00, a more accurate figure will be provided in our final quotation.

Q. Do I need a U.V. on the borehole supply? top of page

A. Not always. Borehole water is usually clear from bacteria (20% are bacteriologically unsafe). If you have bacteria present then they usually have found their way in due to some fault. The most common being surface water running into the bore. Check the drain at the wellhead and also check to see that you are not feeding into a tank with something inside it i.e.: birds, mice, rats etc;

A U.V. can however give added protection and peace of mind.

Q. There is a smell of bad eggs in the water. What is it and can you cure it? top of page

A. The smell is hydrogen sulphide coming from the bore. Generally this can be cured, or at least greatly reduced, by aeration of the water in the filter. In certain circumstances an additional activated carbon cartridge may be required.