The Water Supply (Water Quality) (Scotland) Regulations 2000

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1 - INTRODUCTION

1.1 The quality of drinking water is a vital element of public health and wellbeing. Yet it derives from rivers, reservoirs and groundwater, which are subject to many different sources of potential contamination. The potentially damaging substances, which are likely to appear in drinking water, are covered by European and domestic legislation, which sets limits on the concentrations, which are permissible. These range from absolute zero for potentially dangerous microbiological organisms such as faecal coliforms, to various concentrations for other parameters of health or aesthetic significance. In Scotland, the limits are monitored by the water authorities in some 300,000 tests a year, audited by the Water Services Unit at the Scottish Executive on behalf of Scottish Ministers.

1.2 The existing EC Directive, on which the current legislation is based, was adopted in 1980, on a proposal presented in 1975. Much has changed since then, in our understanding of the health effects of different potential contaminants, in our ability to detect and remove them and indeed in the structure and organisation of the water industry.

1.3 A new Directive on Water Intended for Human Consumption was proposed by the Commission in 1995, and adopted as European law in November 1998. Member States are required to incorporate implementing legislation by 25 December 2000, and to comply with the bulk of the standards in the Directive by 25 December 2003.

1.4 This document sets out how the Scottish Executive proposes to implement the Directive in respect of public water supplies from the Scottish water undertakers. Proposals for private water supplies will be issued later in the year.

1.5 The document is a key part of the first stage in the process to consult on the draft Drinking Water Regulations. It describes the background of drinking water quality legislation, the terms of the new Directive, and a draft of the new Regulations that it is proposed to lay before the Scottish Parliament. It then makes an assessment of the costs of compliance, and raises some specific points on which we would particularly invite comments. Comments are however welcome on all of the draft Regulations, not just the points raised.

1.6 We propose a second stage in the consultation process later in the summer. The main purpose of this will be to provide further information on the potential impact of the draft Regulations on public buildings and to invite comments on this aspect of the proposed legislation.

1.7 Copies of the European Directive, the draft Regulations, and the Regulatory Impact Assessment are attached as Annexes.

1.8 Responses are invited, in accordance with Section 7 of this document, by 21 July 2000.

2 - BACKGROUND

2.1 Current drinking water standards are based on requirements set out in Directive 80/778/EEC relating to the quality of water intended for human consumption. This Directive laid down for the first time a set of mandatory quality standards for drinking water throughout the European Community which Member States were obliged to meet. Member States were required to bring into force any laws, regulations and administrative provisions necessary to comply with the directive by 18 July 1982. Full compliance was required by 18 July 1985. The Directive set standards for 64 parameters and required regular monitoring to ensure that standards were met.

2.2 The importance of wholesome water has long been recognised in the UK and the Directive served to underline and reinforce existing UK standards and practice, rather than alter existing policy and procedures. The Directive was implemented in Scotland by administrative means and the use of existing legislative powers included in the Water (Scotland) Act 1980.

2.3 The current regulatory regime was introduced in 1990 but it was the Local Government etc. (Scotland) Act 1994 and the Water Industry Act 1999 that established the existing framework for water and sewerage services in Scotland.

2.4 Under Section 76A of the 1980 Act water authorities are under a duty when supplying water to any premises for domestic or food production purposes to supply only water which is wholesome at the time of supply. If Scottish Ministers are satisfied that a water authority has failed in its duty under Section 76A, then they will make an order declaring them to be in default and directing them to remedy the default within such times as may be specified in the order. The Act makes it a criminal offence to supply water that is unfit for human consumption. This is not defined in legislation and is interpreted in the courts on a case by case basis.

2.5 Under the Act ‘wholesomeness’ is defined by reference to standards and other requirements set out in the Water Supply (Water Quality) (Scotland) Regulations 1990 (SI 1990 No.119), which have been amended slightly by SI 1991 No.1333. The Regulations incorporate all the standards (maximum admissible concentrations and minimum required concentrations) set out in the EC Drinking Water Directive and include 11 national standards. In total, numerical standards are set for 55 parameters and descriptive standards for a further two. All standards apply to water at the time of supply, and a number apply to water leaving treatment works and to water held in service reservoirs within the distribution system. The Secretary of State may authorise the relaxation of a standard, but only in particular circumstance and where there is no danger to public health.

2.6 The Regulations place responsibility for monitoring the quality of water supplies upon water authorities themselves. Authorities are required to take a specified minimum standard number of samples for each parameter within each water supply zone according to the population served by the zone. The frequency of sampling is at least the minimum required by the EC Directive, and in most cases substantially more. This "self-monitoring" role is subject to checks by local authorities and by the Water Services Unit at the Scottish Executive.

2.7 The regulations also require water authorities to prepare and maintain records on the quality of water supplied in their water supply zones. Registers of results must be open for inspection and copies of information on the register must be provided to any person on demand. Annual reports must be made to local authorities and water authorities must also publish an annual report containing information on the quality of the water supplied.

2.8 The Water Services Unit is responsible for initiating any default orders on behalf of Scottish Ministers. If they are satisfied that a water authority has failed in its duty to supply only water which is wholesome, Scottish Ministers shall make an order under section 76E of the 1980 Act unless they are satisfied that the failure is trivial, or that the authority has given and are complying with an undertaking to take appropriate steps to secure or facilitate compliance.

2.9 The Water Services Unit would not initiate a default order when an authority, after becoming aware of a breach of a regulatory requirement, takes immediate remedial action and demonstrates that compliance has been achieved and is likely to be maintained.

3 - THE NEW DIRECTIVE

3.1 The need for a fundamental review of the Drinking Water Directive (80/778/EEC) was agreed at the Brussels European Council in December 1993. The Commission believed that, although the Directive had been a driving force behind the overall improvement in drinking water quality in Europe over the decade since its introduction, it had shortcomings that needed to be addressed. One difficulty was that the Directive did not provide Member States with an adequate legal framework within which to respond to variations in the quality of raw water and to the technical difficulties encountered in the production and distribution of drinking water. In addition, as the Directive was based on a proposal made in 1975, its ideas and standards corresponded to what was thought to be appropriate at that time. It did not take into account improvements that had taken place since then in scientific understanding and in technology.

3.2 There was also a requirement to reconsider the Directive in light of the subsidiarity principle embodied in the Treaty of European Union signed at Maastricht. This was confirmed at the Edinburgh European Council in December 1992. The conclusions of the Edinburgh Council stated that "On the environment, the Commission intends to simplify, consolidate and update existing texts, particularly those on water, to take new knowledge and technical progress into account."

3.3 On 4 January 1995 the Commission adopted the proposal for a revised Drinking Water Directive. Political agreement on a text for adoption to Common Position was agreed at the Environment Council in Luxembourg on 16 October 1997. The Common Position was formally adopted on 19 December 1997. The European Parliament gave its Opinion (Second Reading) at its sitting on 13 May 1998 and the Commission’s response to the Parliament’s Second Reading amendments was transmitted to Council on 9 July 1998. The new Directive (See Annex A) was adopted in November 1998 and entered into force on 25 December 1998.

3.4 The Directive’s objective is to protect human health from adverse effects resulting from contamination of water intended for human consumption. It sets standards for water intended for drinking, cooking, food preparation or other domestic purposes, regardless or its origin and whether it is supplied from a distribution network, from a tanker, or in bottles or containers. These standards also apply to water used in food production unless the quality of the water cannot affect the wholesomeness of the foodstuff in its finished form.

3.5 Member States must bring into force the laws and regulations necessary to comply with the new Directive by 25 December 2000. Most of the new and tighter standards must be met by December 2003. For bromate, trihalomethanes and lead, interim standards have to be met by December 2003. Final standards are to be met by the end of 2008 for bromate and trihalomethanes and December 2013 for lead.

3.6 The Directive sets parametric values for drinking water standards generally in line with the 1993 World Health Organisation (WHO) guidelines for drinking water quality. These guideline values represent the concentration of a constituent that does not result in any significant risk to the health of a consumer, usually over a lifetime of consumption. The value or concentration set for substances and parameters in the Directive incorporates margins that allow for uncertainties in our current estimation of risk. New parameters have been added where new scientific research has shown this to be necessary, but overall the total number of parameters has been reduced to include only those considered essential at the level of the European Union to ensure a continued high level of health protection. Member States are left to set values for additional national parameters where it is necessary, in light of local conditions, in order to protect human health. The following table shows the Directive’s mandatory standards which are different from the 1989 regulations.

New Mandatory Standards

(a) annual average
(b) three monthly average
(c) weekly average
(d) the formula is [nitrate]/50 + [nitrite]/3 a 1

3.7 The most important change in the Directive is the reduction from 50 µg/l to 10 µg/l in the maximum permitted concentration of lead in drinking water. This change, which is in accordance with the latest recommendations of the World Health Organisation, is introduced primarily in order to protect infants, young children and pregnant women from the neuro toxic effects that are known to contribute to IQ deficits, learning and behavioural problems.

3.8 Monitoring requirements are revised in the Directive, and allow Member States to adapt the amount and nature of monitoring to local conditions. The approach to reference methods of analysis for monitoring has also been revised to permit the use of methods meeting certain performance standards rather than requiring the use of certain defined methods. This allows Member States to adapt their methods to technical and scientific progress without necessitating changes to the Directive.

3.9 The Directive provides a flexible framework of derogations within which Member States can redress failures to meet the required standards provided there is no potential danger to human health and that the supply of drinking water cannot be maintained by any other reasonable means.

4.- CONTENT OF THE PROPOSED REGULATIONS

4.1 The proposed Regulations (see Annex B) consolidate the existing Water Supply (Water Quality) (Scotland) Regulations 1990 together with the amendments. They also implement the provisions of the new Drinking Water Directive (the Directive), incorporating not only the new parameters, but also the changes to the conduct of water quality regulation that it requires.

Part I: General

4.2 Part 1 sets out the timetable for the different Regulations to enter into force. For most, this is 25 December 2003, which is the date by which the standards of the new Directive need to be met. Some provisions come into force on 1 January 2001 — these contain transitional arrangements which are designed to ensure that the work which water authorities need to do in order to comply is finished by December 2003. Finally, most of the monitoring arrangements enter into force on 1 January 2004. This is because monitoring frequencies, the collection of data, and reporting (including to the European Commission) are all done on a calendar year basis. In fact, full monitoring coverage of the new Directive’s parameters will be in place from 1 January 2001 through a combination of monitoring under the 1989 regulations, and monitoring under the transitional arrangements.

Part II: Water Supply Zones

4.3 Part II. Monitoring the quality of water, and reporting the results, is undertaken on the basis of "water supply zones". These provide manageable areas for regulation that are more consistent in size than, for instance, the areas covered by treatment works. Regulation 3 permits zones to cover populations of up to 100 000, compared with 50 000 at present, and requires water authorities to define and designate these.

Part III: Wholesomeness

4.4 Part III is where the substantive requirements for water quality are set out. The Water (Scotland) Act 1980 (the Act), requires water authorities to supply only water which is wholesome at the time of supply, and it is here that the term is defined. Regulation 4(1) sets out the purposes for which water subject to the wholesomeness definition is supplied. This includes water supplied to premises in which food is produced, although the quality of water as it is actually used for food production is the subject of different controls. Regulation 4(2) refers to Tables A and B, which are contained in Schedule 1 of the draft Regulations. These include the mandatory standards set out in the new Directive. Those of the standards that are different from the 1990 regulations are set out in paragraph 3.6.

4.5 Tables A and B also include some national standards, not mandatory under the Directive, which were included in the 1990 regulations, and which we are proposing should be retained (see paragraph 6.1 below). There are also more general requirements for drinking water not to contain anything at concentrations that would constitute a potential danger to human health. Regulation 4(3) maintains, as a national standard, the requirement that where water is softened before supply, it should nevertheless retain hardness of at least 60 mg of calcium per litre (or its magnesium equivalent). It does not require the hardening to this level of naturally soft water. These standards apply at the consumer’s tap, while others, set out in Regulation 4 (5)(6) and (7), apply at treatment works or service reservoirs.

Parts IV and V: Monitoring

4.6 Parts IV and V contain provisions for monitoring the quality of drinking water. These closely follow the arrangements contained in the 1990 Regulations, adjusted where necessary to ensure compliance with the requirements of the new Directive, including the definitions of check and audit monitoring, and the indications, in Regulation 6(2) and Table 1 of Schedule 3, as to which should be employed. Sampling is at consumers’ taps, except for those parameters, many of which are specified, where Scottish Ministers are satisfied that samples taken from treatment works will produce data that is representative of the position at consumers’ taps. A general provision (Regulation 10) requires authorities to take samples to establish whether water is wholesome, whenever they suspect that it might not be, other than through contamination by one of the listed parameters, i.e. that it might contravene the more general requirements of Part III. Sampling at consumers’ taps is generally to be by random selection.

4.7 Part V includes further provisions as regards monitoring, including the extra monitoring needed when a new source of water is to be used. Conversely, reduced monitoring frequencies apply where there is a good history of full compliance with the appropriate parameters. Further regulations cover the analysis of samples, by specified or authorised methods, and methods which meet specified performance in terms of trueness, precision, and limit of detection.

Part V1: Investigations, authorisation of departures and remedial action

4.8 Part VI sets out what should happen when something goes wrong or appears to go wrong, with the quality of drinking water. It is important to emphasise that the standards for the different wholesomeness parameters are very tight. They are, in the main, based on World Health Organisation guidelines as to concentrations in water that are safe over a lifetime’s drinking. Those guidelines themselves are set with substantial safety margins. For the chemical parameters in particular therefore, a limited and/or temporary failure to meet the standards does not necessarily give rise to any risk to health, whereas remedial action might take a long time to put in place, and the provision of water from alternative sources may be impracticable. On the other hand, microbiological contamination of water can lead to serious diseases such as cholera. The provisions of this part are therefore based on the need to assess any particular situation and make an appropriate and proportionate response.

Investigations

4.9 In response to any failure to meet a standard for drinking water quality, the water authority must establish the cause and nature of the failure. This means establishing whether the failure is due to the quality of the water supplied to the premises, or to some shortcoming within the premises themselves (for instance a lead pipe bringing water into the house). The water authority is responsible only for the former — where water becomes unwholesome within the premises being supplied, this is the responsibility of whoever deals with the maintenance of those premises (but see below). On completion of the investigation, the water authority must inform Scottish Ministers (in practice the Water Services Unit) of its findings.

4.10 The new Directive and Regulations introduce a new concept of indicator parameters. These are subject to monitoring under Parts IV and V of the Regulations, but they do not contribute directly to the definition of wholesome water. Under the Directive, remedial action is necessary in cases where the specifications for indicator parameters are exceeded, only where the Member State judges there to be a risk to health. Regulation 18 provides for a reduced investigation and reporting responsibility in respect of cases where the specifications for indicator parameters are exceeded. In practice, the Water Services Unit will issue guidance as to those (generally higher) levels of the indicator parameters that Scottish Ministers consider represent a concentration or value constituting a potential danger to human health. These would then be covered by the general provisions for the definition of unwholesome water, and would therefore be subject to the more urgent and stringent requirements for investigation and reporting.

Water which becomes unwholesome through contamination by lead, and/or within a consumer’s premises.

4.11 The new Directive for the first time imposes limited obligations on Member States in respect of water quality at the consumer’s tap, rather than at the point at which it leaves the company’s pipes. It is there (at the tap from which drinking water is normally taken) that Directive’s standards formally apply. However, under most circumstances, the Member State is deemed to be in compliance with the Directive, if failure to meet the standards can be shown to be due to deterioration within premises. This will most commonly result from the use of lead pipes to carry water from the water authorities’ pipes to and within a building. Those responsibilities that remain are reflected in various elements of the draft regulations. This is described in the following paragraphs — it is necessary to take the regulations out of sequence to explain them clearly.

4.12 Where there is a risk of failure to meet the lead (or copper) standard, water authorities will be obliged to treat the water so as to minimise its potential to dissolve lead (or copper) from pipes (Regulation 29 27). Such water treatment will be carried out wherever it is practicable and would be effective in reducing lead (or copper) levels. Copper is included because of the copper standard in the Directive. In practice, cases of failure to meet the copper standard are expected to be very rare.

4.13 Regulation 17(9) reflects the fact that when the lead standard is exceeded, and there are lead pipes in contact with the water, both within the authority’s responsibility and within premises, it is not possible to allocated blame to either one or the other. Where the lead (or copper) standard is breached, the authority has to replace or otherwise make safe any lead (or copper) pipes within its own distribution system, regardless of whether the main cause of the failure lies in the authority’s pipes or those of the consumer. This replaces a different provision in the 1990 regulations, which requires the authority to replace its lead pipes when requested to do so by a consumer, and when the consumer is replacing their own lead pipes. The new provision is automatic, but only when there is a breach of the standard.

4.14 Under Regulation 40 38, authorities will need to draw up programmes of work for compliance with the Directive standards. This will include programmes to minimise plumbosolvency through water treatment, but also programmes to replace (or otherwise modify) lead pipes where such treatment is not sufficient to ensure that the lead standard is complied with. For the 10µg/l lead standard, these pipe replacement programmes will extend towards December 2013 by which time the standard must be complied with.

4.15 Finally, under Regulation 17 and elsewhere, water authorities are required, when discovering a failure to meet the standards which is due to the domestic plumbing, to inform the consumer as to what the problem is and how it might best be tackled. This is not restricted to the lead standard — for instance microbiological contamination could result from faults within a building’s plumbing system, particularly if water is stored at some intermediate point between entering the building and being supplied to taps.

4.16 The provision whereby a Member State is deemed to be in compliance with the Directive, notwithstanding deterioration in water quality within consumer premises, does not extend to premises such as restaurants, schools and hospitals where water is supplied to the public. Transposition of this aspect of the Directive is a complex issue, on which the Scottish Executive has not yet decided what it considers to be the best way forward. Within the current draft, in the case of failure caused by the pipework within premises from which water is supplied to the public, Regulation 17 merely contains provision for the water authority to inform a third party to be nominated by Scottish Ministers. Such an ability to ensure that an appropriate regulator is informed, will need to be supplemented by powers for that regulator to enforce compliance, whether contained within the Water Supply (Water Quality) Regulations 2000 or elsewhere. This will be the subject of a separate consultation.

Action by Scottish Ministers

4.17 Under the Act and the 1990 regulations, where the supply of unwholesome water occurred, and this was judged not to be trivial or unlikely to recur, Scottish Ministers could make an order declaring the authority to be in default and require work to be carried out to put matters right. However, Scottish Ministers can instead accept a legally binding undertaking from an authority that it will take the appropriate steps — compliance with which is itself enforceable. In practice acceptance of undertakings became the rule. It was a quick and convenient method of achieving the necessary compliance with standards, but it was not specifically catered for by the original Directive, and left a great deal to the discretion of Scottish Ministers. The Drinking Water (Undertakings) (Scotland) Regulations, due to come into force later this year, aim to ensure that legislation specifically defines such undertakings. The new Drinking Water Directive provides for "derogations" which can be granted for periods of up to 3 years at a time, and sets out a detailed framework governing the conditions under which such derogations can be granted. The provisions include the specification of concentrations and values (less stringent than the standards) to be complied with during the period of the derogation. However, this mechanism is not available for the microbiological parameters contained in the Directive. Regulations 19-24 reflect these provision of the new Directive. Under Regulation 19, for any breach of the Directive’s microbiological parameters, which is not adjudged to be either trivial or unlikely to recur, Scottish Ministers have no option but to move directly to a default order.

4.18 The remainder of this Part implements the mechanism for "derogations" under the Directive, which are here described as authorisations to depart from the wholesomeness provisions contained in Part III of the Regulations (i.e. to supply water that is unwholesome for the period of the departure), or "authorised departures." Regulation 20 sets out the conditions under which a departure can be authorised, the matters which the water authority must put into its application, and the local bodies to whom the application should be copied - the local authority, health authority, and the Water Industry Commissioner for Scotland. These all have the right to make representations to Scottish Ministers in connection with the application. Regulation 21 sets out what the authorisation should contain, and the remainder of the Part includes the various administrative provisions, following closely the provision of the Directive, which need to be implemented.

Part VII: Water Treatment

4.19 Regulation 26 sets out the basic requirements to disinfect raw water, and to take such other necessary action to conform with EC and national arrangements for classification, abstraction and treatment of waters intended for human consumption — there are no substantive changes from the 1990 regulations. Regulation 29 27 deals with plumbosolvency treatment (as outlined above), while Regulations 3028 and 31 29 deal with approval mechanisms for the use of substances, products and processes in connection with the supply of water, with only minor changes from the existing regime. Regulation 32 30 sets out the offences connected with this Part, with no substantive change from the existing Regulations.

Parts VIII-X: Records and information, functions of local authorities and enforcement

4.20 These are technical provisions, not showing any substantive change from the existing Regulations. They include an open-ended requirement for the keeping of all records except the results of analysis of samples.

Part XI: Transitional Provision etc.

4.21 Regulation 39 37 amends the 1990 Regulations so as to require additional monitoring and reporting against the new standards, while the old ones remain in place. This is for the purpose of assessing the work needed in order to comply with the new standards. As mentioned above, Regulation 40 38 — supplemented by Schedule 6 - requires water authorities to submit programmes of work to Scottish Ministers, outlining what it is they expect to do in the interim period, in order to ensure compliance with the standards by the due date. It will then be for Scottish Ministers to approve programmes of work (with or without modification).

5 - REGULATORY IMPACT ASSESSMENT

5.1 A regulatory impact assessment for the Regulations is at Annex C. It identifies the main costs arising from the new Regulations as those falling on water suppliers arising from the need to meet the more stringent standards, and those passed on by water authorities to consumers, most businesses and industry in the form of increased water charges.

5.2 It is difficult to estimate the cost to the water industry of compliance with the Drinking Water Regulations. A single investment, for example in a new treatment facility, will be directed at a number of objectives, such as increasing capacity, installing automated monitoring, compliance with pre-existing regulations, the DWRs, the Crypto directive. It is therefore difficult to estimate what element of the cost should be ascribed to the DWRs. In England and Wales, the regulatory system includes a detailed assessment of capital investment by objective, allowing more precision. Work on a similar system in Scotland is being taken forward by the Water Industry Commissioner. Over the next two years, the period covered by the Quality and Standards paper published in 1999, investment in water treatment in Scotland will amount to some £180m. Some of this expenditure will be directed at satisfying the requirements of these regulations. The overall level of expenditure thereafter will be determined by the new Quality and Standards exercise, and will include further expenditure directed at the 2003, and subsequent, deadlines

5.3 The effect of passing on the cost of the new Directive standards to domestic customers, before the savings identified by the Water Industry Commissioner are taken into account, would be to raise average bills. By 2004-2005 the Commissioner estimates that [on average 1.7% or £1.80 of a typical domestic bill of £107.90] will be attributable to the additional costs of meeting the new drinking water standards.Some costs will fall to domestic, public and voluntary sector customers by way of water charges. It is not possible to quantify with certainty the proportion of charges that may arise from compliance with the standards although a figure of it has been suggested that perhaps up to 5% of an average household bill in 2004/5 may be due to compliance. However with improvements in efficiency plus an investment of £1.8bn in the Scottish Water Industry over the next three years increases will be kept to a minimum.

5.4 Bills for small business users are similar to those for domestic users and the impact of the Regulations on these bills will be similar to that shown for domestic customers. It is more difficult to predict the impact of the new Regulations on bills for large business users. However, if long run marginal costs are used as the basis for setting tariffs for these customers, the impact of the new Regulations on bills will be similar to the impact on domestic bills.

5.5 Introducing the new Regulations will benefit consumers who will receive drinking water that meets up to date World Health Organisation standards. As a result they will be less likely to experience long term adverse health effects. The single most important benefit is likely to arise from the introduction of the Directive’s new lead standard of 10 µg/l from 2013. This will protect infants, young children and pregnant women from the neuro toxic effects of lead that are known to contribute to IQ deficits, learning and behavioural problems. The total health benefits, for England and Wales, of achieving the final lead standard have been estimated at between [£724m] £724m and [£2741m], £274m and the non-heath benefits at between [£124m and £360m] £124m and £360m depending on the assumptions used in the evaluations. (Scottish figures are not available. However as a general indication of the scale of the benefits to Scotland we might state them as 10% of the English and Welsh figures noted above)

6 ISSUES FOR CONSULTATION

National standards for drinking water quality

6.1 The UK has traditionally set some national drinking water standards that are more stringent than those now required by EC legislation. These standards are based on the best UK scientific and medical advice and increase protection to consumers. We propose that these standards should be maintained and included in the new Regulations, given the benefits and the fact that there are no new costs associated with their maintenance.

Microbiological quality parameter

6.2 The 1998 Directive has a mandatory standard of 0/100 ml for E coli (equivalent to the standard for faecal coliforms in the 1990 Regulations which implement the 1980 Directive) and an indicator parameter value of 0/100 ml for coliform bacteria (total coliforms in the 1990 Regulations). These values must be applied and monitored at consumers’ taps.

6.3 The 1990 Regulations also include a mandatory standard for faecal coliforms of 0/100 ml in the water leaving treatment works and in service reservoirs. We propose to retain the mandatory standard for E coli as a public health measure because the detection of E coli in treated water leaving a treatment works or in a service reservoir indicates the presence of contaminating material of faecal origin. Such a situation is potentially dangerous and requires immediate investigation and action by the water supplier.

6.4 The 1990 Regulations include a mandatory standard for total coliforms of 0/100 ml in water leaving treatment works and a similar standard for water in service reservoirs. At service reservoirs the standard must be met in 95% of samples. We propose to retain these mandatory standards for coliform bacteria as a public health measure because the detection of coliforms in treated water indicates the possible presence of contaminating material of faecal or environmental origin that requires immediate investigation and if necessary action by the water supplier. If more than 5% of samples taken from a service reservoir contain coliform bacteria it indicates that the reservoir may not be structurally sound.

6.5 The 1990 Regulations include from the 1980 Directive a mandatory standard for total coliforms of 0/100ml that must be met in 95% of samples taken from consumers’ taps. In many cases the detection of coliform bacteria in samples from consumers’ taps is due to deficiencies in the hygienic condition of the consumers’ pipework and taps and is not due to the quality of water supplied by the water supplier. We propose to include coliform bacteria as an indicator parameter at consumers’ taps with a value of 0/100 ml. When coliform bacteria are detected at a consumer’s tap we propose that the regulations require the water supplier to establish whether the cause of the detection was associated with the hygienic condition of the consumer’s plumbing and if so, to advise the consumer on the remedial action they should take. If the origin of the coliform bacteria was associated with the water supplier’s distribution system, the water supplier would be required to determine the cause and, if there was a potential risk to public health, to take appropriate action. Consultees might like to consider whether the current mandatory standard for coliform bacteria of 0/100 ml to be met in 95% of samples from consumers’ taps should be retained instead of the proposed indicator parameter value.

Aesthetic quality parameters

6.6 The 1990 Regulations include mandatory standards from the 1980 Directive for aluminium, iron, manganese, colour, turbidity, odour and taste that apply at the point of supply. The 1998 Directive does not have mandatory standards for these parameters. They are classed as indicator parameters with the values given for aluminium, iron and manganese and a specification of "acceptable to consumers and no abnormal change" for colour, turbidity, odour and taste.

6.7 The aesthetic quality of water supplies is very important to consumers. They notice when the water supply is discoloured or it has an unpleasant taste or odour. It is important therefore to ensure that water authorities treat and distribute water in such a way that its appearance, taste and odour are acceptable to consumers. What is acceptable to consumers may vary widely depending on circumstances and what they are used to.

6.8 We propose therefore to retain the current mandatory standards for these aesthetic parameters. They have served consumers well for the last 10 years. They have enabled the Water Services Unit to require water authorities to improve treatment and renovate parts of the distribution system that give rise to discoloured water. Renovation of the distribution system is a long-term programme that will take water authorities several years to complete. Mandatory standards for aesthetic parameters are essential to ensure that this programme is completed and thus minimise the risk that water of unacceptable aesthetic quality is supplied to consumers.

Total Hardness

6.9 The 1990 Regulations implemented the 1980 Directive’s requirements for a minimum total hardness of 60 mgCa/l and a minimum alkalinity of 30 mgHCO₂/l for water supplies that were softened or desalinated. These requirements were omitted from the 1998 Directive.

6.10 In 1994, the UK Department of Health (DH) report "Nutritional Aspects of Cardiovascular Disease", stated that "in view of the consistency of the [epidemiological] evidence [of a weak inverse association between natural water hardness and cardiovascular disease mortality], it remains prudent not to undertake softening of drinking water supplies". DH has advised that studies published since then have not changed this position and that the minima above should be retained as national standards.

6.11 We propose therefore to retain the minimum standard for total hardness of 60 mgCa/l for softened and desalinated water. We are not proposing to retain the minimum standard for alkalinity as this is unnecessary. The minimum standard for total hardness is sufficient to ensure that softened water is not put into supply.

Sodium

6.12 The 1990 Regulations implemented the 1980 Directive’s requirement of a standard for sodium of 150 mg/l to be met in 80% of the samples taken over 3 years. The 1998 Directive does not have a mandatory standard for sodium but includes it as an indicator parameter with a value of 200 mg/l.

6.13 DH has advised that there should be a mandatory standard for sodium of 200 mg/l applied as a maximum rather than a percentile. The primary aim is to help prevent infantile hypernatraemia and a secondary aim is to assist recommendations to reduce sodium intake in the general population. We propose therefore to have a mandatory sodium standard of 200 mg/l.

Tetrachloromethane

6.14 The 1990 Regulations contain a mandatory national standard of 3 µg/l for tetrachloromethane (carbon tetrachloride) based on the 1984 World Health Organisation (WHO) tentative guideline value. It was necessary to regulate tetrachloromethane because it was found to contaminate some groundwaters used as drinking water sources in urban and industrial areas. The 1998 Directive does not include a standard for tetrachloromethane.

6.15 The 1993 WHO guideline for tetrachloromethane is 2 µg/l and the value is no longer tentative. WHO specifically states that short term deviations above guideline values do not necessarily mean that the water is unsuitable for human consumption. Furthermore the value for this substance has a wide margin of safety. Therefore we propose to retain the current mandatory standard of 3 µg/l for tetrachloromethane.

pH value

6.16 The 1990 Regulations contain mandatory standards for pH value of 5.5 as a minimum and 9.5 as a maximum. The latter implements the 1980 Directive’s maximum and the minimum as a national standard. The 1998 Directive does not have mandatory standards for pH value. Instead it has indicator parameter values of greater than or equal to 6.5 and less than or equal to 9.5 with a note that the water should not be aggressive (i.e its tendency to corrode).

6.17 The prime aim of controlling the pH value of water supplies is to ensure that the water does not adversely affect the materials of the water supplier’s distribution system and the plumbing materials and fittings within the consumer’s premises. To achieve this we propose to retain mandatory standards for pH value. We propose 6.5 as the minimum pH value to give better corrosion protection than the current 5.5. We seek consultees’ views on whether the maximum pH value should be retained at 9.5 or whether a new value of 10.0 should be regulated. A value of 10.0 would allow more flexibility to optimise plumbosolvency control compared with 9.5 as it would assist in maintaining relatively high pH values throughout long distribution systems and thus minimise lead concentrations. On the other hand it may increase the aggressiveness of water towards other materials.

Indicator parameters

6.18 998 Directive also has indicator parameter values or specifications for ammonium, chloride, clostridium perfringens, colony counts, conductivity, sulphate, total indicative dose for radioactivity, total organic carbon, tritium and turbidity (for water leaving treatment works). We propose to regulate these as indicator parameter values for monitoring purposes. Failure to meet one of these values or specifications does not mean that the water is unwholesome. Action will only need to be taken when the failure to meet the value or specification is of such a magnitude or duration that it poses a risk to public health. The Water Services Unit will issue some general guidance on the action that water suppliers should take in these circumstances. In respect of sulphate, it has been suggested that we should include a mandatory standard of 500 mg/l as well as the indicator parameter value of 250 mg/l. The mandatory standard would be based on preventing infantile gastroenteritis. We seek consultees’ views on this issue.

Cryptosporidium

6.19 Scotttish Ministers issued a Direction to water authorities regarding cryptosporidium in water supplies in February 2000. The Direction required the water authorities to implement the recommendations contained in the third report by the Group of Experts on Cryptosporidium in Water Supplies published in November 1998 and to carry out risk assessments on public drinking water supplies in Scotland for cryptopsporidium. The draft Regulations do not incorporate cryptosporidium since it is not a parameter covered by the EC Directive and because the Executive believes that the regime that is already in place will prove to be a significant step in protecting the community against this organism. The Executive does not intend to make changes to the obligations and procedures set out in the Cryptosporidium Directive, however it recognises the opportunity to allow comment on the exclusion of Cryptosporidium from the draft regulations.

Maintenance of Records

6.20 Draft regulation 33 31 covers the maintenance of records, and largely reflects the the existing provisions. Paragraph 4 provides that records of the results of analysis of particular samples need not, by virtue of this regulation, be kept for more than 5 years. The implication is that the other records covered by the Regulation need to be kept for all time. The Executive is sympathetic to the suggestion that this may be excessive, and would welcome views as to the appropriate periods for which the various types of information need to be retained.

Public Buildings

6.21 This draft of the Regulations is largely silent on the question of the wholesomeness of water at the tap in premises and establishments in which water is supplied to the public (see paragraph 4.16 above). The Executive is still considering various ideas for the transposition of this part of the Directive. It will consult on its preferred option separately, whether transposition is done as part of these Regulations or separately.

7 - RESPONSES TO THE CONSULTATION

7.1 Consultees are asked to send their responses to Janet Brunton, Scottish Executive, Water Services Unit, 1-H82, Victoria Quay, EDINBURGH EH6 6QQ. Alternatively, E-mail responses may be sent to waterservices@scotland.gov.uk. Responses should reach the Executive no later than 21 July 2000.

7.2 The Executive may wish to publish responses to the Consultation document in due course, or deposit them in Parliamentary or Departmental Libraries, where they may be consulted. If this is done, all responses will be deposited unless a respondent specifically asks the Executive to treat their response as confidential. Should you not want a copy of your reply made available to the public please make this clear in your response. Confidential responses will nevertheless be included in any statistical summary of numbers of comments received and views expressed.

7.3 This publication will be available on the Scottish Executive web site at http://www.scotland.gov.uk

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