Annual Report on Water Quality Borough Council 2019

April 2020

Table of Contents

1 Introduction ...... 3 2 Water Treatment Works, Service Reservoirs and Water Supply Zones ...... 3 3 Water Quality ...... 4 4 Customer Contacts ...... 5 5 Section 19 Undertakings, Authorised Departures & Regulation 28 Notices...... 5 6 Notifiable events ...... 6 7 Further information and advice ...... 6 8 Appendix One ...... 8 9 Appendix Two ...... 9

1 Introduction

Affinity Water produces an annual report for each local authority regarding the general quality of water supplied to premises in the authority’s area. The information includes results of samples taken from water supply zones in the authority’s area of responsibility and any associated exceedences (see section 3 Water Quality) relevant to those supply areas i.e. exceedences from supplying water treatment works and service reservoirs. In 2019, 99.97% of the 190,000 tests taken as part of the Company’s regulatory monitoring programme complied with the standards confirming that drinking water quality continues to be of a very high standard. The report also includes details of the actions taken to comply with any enforcement orders, authorised departures and notices under regulation 19(4). This report is for the Dacorum Borough Council and covers the year ending 31 December 2019.

2 Water Treatment Works, Service Reservoirs and Water Supply Zones

In 2019, the Company met the demand for drinking water by operating 93 water treatment works (WTW). The water supply to the area covered by the Council was provided by the following water treatment works:

Amersham Batchworth Friars Wash Gerrards Cross Hunton Bridge Marlowes Mill End Northmoor Piccotts End

Treated water from the above works is either passed directly into supply or via one of the following service reservoirs:

Adeyfield 2 North West Bovingdon 2 South East Boxted Heronsgate 2 Heronsgate 3 High Street Green WT Kingshill 1 Kingshill 2

The Company’s area is divided into discrete Water Supply Zones, each with a population of 100,000 or less. In 2019, Affinity Water had 89 such zones.

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In 2019, Dacorum Borough Council’s area was served by Zone:

026 Caddington / Eaton Bray 033 Hemel / Potten End 034 / 035 037 Berkhamsted 038 039 Hemel / 042 Chesham / Bovingdon 045 Chorleywood / Gerrards Cross

Maps and results of analyses for the above zones can be found in Appendix 2.

3 Water Quality

In March, coliform bacteria were detected in a sample taken from a customer's property in Zone 033. Our investigation identified that the most likely cause of the failure was the condition of the tap where the sample was taken. The customer was informed of the situation and actions to take to prevent contamination of taps. Coliforms do not pose a risk to public health.

During June, Nickel was detected at a concentration above the standard in a sample taken from a customer's property in Zone 034. Our investigation established that the supplying treatment works were operating satisfactorily and there were no significant activities on the local distribution network. We identified the kitchen tap was the source of the nickel and have advised the customer accordingly.

During October, a sample taken from a customer's property in Zone 039 had a slight 'chlorophenol' Quantitative Odour detected in it. Our investigation identified the plumbing in the property as the most likely cause for the exceedance. The customer at the property had not noticed an unusual odour to their water supply and there were no complaints from customers in the Hemel Hempstead area regarding an unacceptable odour to the water supply around the time the sample was taken.

All exceedences of the standards are reported to the Drinking Water Inspectorate (DWI) in monthly exception reports. In the event that the DWI is not satisfied with the Company’s explanation of the circumstances and the action taken, enforcement action can be initiated.

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4 Customer Contacts

Under the Water Industry (Suppliers’ Information) Direction 2019, the Company must provide the DWI with annual information on all consumer contacts received related to drinking water quality. For each water supply zone, the consumer contacts are separated into five main categories (with further division into sub-categories). An overall rate of contact per 1000 population is calculated for each zone as well as contact rates for combined categories. The customer contact data for water supply zones within your Council’s area of responsibility is shown in the table below.

Zone Zone Rate Zone Rate Overall zone rate (Population) (Consumer (Appearance, taste (Contacts per 1000 Enquiries & and odour & illness pop.) Drinking Water per 1000 pop.) Quality Concern per 1000 population) Company average 0.25 0.81 1.06 Z026 (12,474) 0.16 1.20 1.36 Z033 (15,530) 0.26 1.35 1.61 Z034 (5,809) 0.52 1.21 1.72 Z035 (5,489) 0.55 1.28 1.82 Z037 (17,346) 0.35 0.40 0.75 Z038 (80,906) 0.16 1.04 1.20 Z039 (31,476) 0.10 1.18 1.27 Z042 (28,228) 0.39 1.03 1.42 Z045 (71,353) 0.36 0.70 1.07

5 Section 19 Undertakings, Authorised Departures & Regulation 28 Notices

Water supply zones in the Council’s area were not affected by the Company’s Section 19 Undertakings. The Company did not have any Authorised Departures in place in the Council’s area during 2019. In order to meet the standard relating to lead, the Company has continued operating orthophosphate dosing plants at 38 sites across the Company’s area. Zones 042 and 045 receive water dosed with orthophosphate.

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6 Notifiable events

Under the Water Industry (Suppliers Information) Direction 2019, the DWI must be notified of any situation where water quality is likely to be, or has been, adversely affected. Since 2009 the DWI has been using an event classification system to assess and quantify the significance of a notifiable event, giving each one a number (1 to 5) with an equivalent rating (“not significant” through to “major”). The Company regards any event classified as a 3 Significant or above as being equivalent to the previously designated ‘incident’. During 2019 there was one notifiable event within your Borough’s area of responsibility. During September, we were contacted by a consumer from Common Lane, Kings Langley regarding a diesel odour in the water supply to the property. We advised the consumer to use bottled water for drinking and cooking purposes during the investigation. Our investigation confirmed the diesel odour was confined to the single property and the odour coincides with plumbing work to the supply pipe at the property. Specifically, the relaying of the pipe to an area potentially contaminated by the removal of an old heating fuel tank. We recommended the consumer reroute their water supply pipe away from the contamination and that a suitable barrier material should be used. Samples taken following the subsequent remedial work were satisfactory with no odour detected and we lifted the restriction notice. The event was classified by the DWI as not significant.

7 Further information and advice

For further information and advice on all water quality matters please contact: Eddie Lintott Water Quality Manager Affinity Water Tamblin Way Hatfield AL10 9EZ

Telephone: 0345 357 2407

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Appendices

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8 Appendix One – Map

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9 Appendix Two – Water Quality Results

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