Drinking Water Quality Management Plan - City of Gold Coast · 2019. 6. 23. · Drinking Water...

Drinking Water Quality Management Plan

Annual Report 2019-20

Gold Coast Water and Waste

Drinking Water Quality Management Plan Annual Report 2019 – 2020 Page 2 of 20

Table of Contents

1. Service Provider Details ............................................................................................................................... 3

2. Glossary of terms .......................................................................................................................................... 4

3. Introduction .................................................................................................................................................... 5

4. Overview of operations ................................................................................................................................. 6

4.1 Schematic Layout of the Scheme ....................................................................................................... 6

4.2 Water Source details .......................................................................................................................... 6

4.3 Bulk Water .......................................................................................................................................... 6

4.4 Disinfection ......................................................................................................................................... 6

4.5 Drinking water supply network ............................................................................................................ 6

5. Compliance with water quality criteria ........................................................................................................ 8

5.1 Overview of water quality monitoring program ................................................................................... 8

5.2 Summary of water quality compliance ................................................................................................ 8

6. Notifications to the Regulator under sections 102 and 102A of the Act.................................................. 9

6.1 Non-compliances with the water quality criteria and corrective and preventive actions undertaken. 9

Detection of benzene – Rainbow Drive, Mudgeeraba .............................................................. 9 6.1.1

Detection of benzene – Wepham Court, Arundel ..................................................................... 9 6.1.2

7. Customer complaints related to drinking water quality .......................................................................... 11

8. Actions taken to implement the DWQMP .................................................................................................. 12

8.1 Progress in implementing the risk management improvement program. ......................................... 12

8.2 Revisions made to the operational/verification monitoring program to assist in maintaining the

compliance with water quality criteria in verification monitoring. ...................................................... 12

9. Outcome of the review of the DWQMP and how issues raised have been addressed ........................ 13

10. Findings and recommendations of the DWQMP auditor ......................................................................... 15

11. Appendix A ................................................................................................................................................... 16

12. Appendix B ................................................................................................................................................... 18


1. Service Provider Details

DETAIL INFORMATION

Service Provider ID (SPID) 0540

Name Gold Coast Water and Waste

Address PO Box 5042

Gold Coast MC 9729

Telephone 1300 465 326

Email [email protected].

Website www.goldcoast.qld.gov.au

LGA covered by this plan City of Gold Coast

Water Supply Schemes covered by this plan Gold Coast Region

mailto:[email protected]

http://www.goldcoast.qld.gov.au/


2. Glossary of terms

GLOSSARY OF TERMS

ADWG Australian Drinking Water Guidelines (2011). Published by the National Health and Medical Research Council of Australia

BTEX Acronym for chemicals associated with petroleum spillage; Benzene, Toluene, Ethyl-benzene and Xylene

City City of Gold Coast

DNRME Department of Natural Resources, Mines and Energy

DWQMP Drinking Water Quality Management Plan

E. coli Escherichia coli, a bacterium which is considered to indicate the presence of faecal contamination and therefore potential health risk

FY Financial Year

GCDP Gold Coast Desalination Plant

GCWW Gold Coast Water and Waste

HACCP Hazard Analysis and Critical Control Points

LGA Local Government Area

mg/L Milligrams per litre

ML Megalitres (1 million litres)

MPN/100mL Most Probable Number per 100 millilitres

NTU Nephelometric Turbidity Units

QWSR Queensland Water Supply Regulator

SPID Service Provider Identification Number

SRWP Southern Regional Water Pipeline, part of the SEQ Supply System

the Act Water Supply (Safety and Reliability) Act 2008

the Regulator Queensland Water Supply Regulator

THM Trihalomethanes

WSD Water Supply District

WTP Water Treatment Plant

< Less than

> Greater than


3. Introduction

This Drinking Water Quality Management Plan (DWQMP) Annual Report has been prepared to meet the

requirements of sections 141 and 142 of the Water Supply (Safety and Reliability) Act 2008 (the Act), for the

2019-20 Financial Year (FY).

This DWQMP Annual Report documents the performance of the Gold Coast Water and Waste (GCWW)

drinking water service with respect to:

The water quality performance of GCWW’s drinking water supply;

Details of information provided to the Regulator under sections 102 and 102A of the Act, for

noncompliance with water quality criteria;

The actions taken to implement the DWQMP;

Details of customer complaints relating to drinking water quality;

This report assists the Queensland Water Supply Regulator (Department of Natural Resources, Mines and

Energy (DNRME)) to determine whether the approved DWQMP and the approval conditions have been

complied with. It also provides a mechanism for GCWW to report publicly its performance in managing drinking

water quality. This report is available on the City of Gold Coast (the City) website (www.goldcoast.qld.gov.au).

This report has been prepared in accordance with the Drinking Water Quality Management Plan Report

Guidance Note 2018 and the Drinking Water Quality Management Plan Report Template published by DNRME.



4. Overview of operations

4.1 Schematic Layout of the Scheme

Figure 1 (next page) is a schematic diagram showing the layout of the GCWW drinking water scheme from

catchment to consumer. The linkages between the major infrastructure elements and the ownership of the

infrastructure have been illustrated.

4.2 Water Source details

The Hinze Dam/Little Nerang Dam system is the primary water source for the city. It has a combined capacity of

approximately 320GL. Hinze Dam upgrades, completed in 2011, increased its capacity and provides flood water

storage. The 207 square kilometre catchment area for Hinze Dam includes the Numinbah Valley and

Springbrook Plateau, with about 77 per cent covered by native bush land within State Forests and National

Parks. The Gold Coast Desalination Plant (GCDP) was brought online in 2009 to provide an additional source of

drinking water, converting seawater from the Pacific Ocean into high quality drinking water.

4.3 Bulk Water

GCWW receives treated drinking water from the bulk water supplier Seqwater. Drinking water is treated at the

Molendinar and Mudgeeraba WTPs with a combined capacity of approximately 265 ML/day, as well as the

GCDP with a capacity of 133 ML/day. Additional water is occasionally received from the Mt Crosby WTP via the

Southern Regional Water Pipeline (SRWP) which has a capacity of 130 ML/day.

4.4 Disinfection

The Australian Drinking Water Guidelines (ADWG) 2011 states that ‘disinfection is the single process that has

had the greatest impact on drinking water safety’. The City’s drinking water supply is disinfected with chlorine

(hypochlorite). GCWW strive to ensure that a disinfection residual of between 0.2mg/L and 1.8mg/L is present

throughout the drinking water supply network at all times. This is to help protect against potential

recontamination of the drinking water supply and protect public health.

4.5 Drinking water supply network

Treated drinking water is transferred from the Seqwater water treatment facilities into the GCWW drinking water

system via bulk water transport pipelines which are owned and operated by Seqwater. The GCWW drinking

water scheme services the area from Stapylton in the north to Coolangatta in the south. GCWW maintains in

excess of 3500 kilometres of water mains supplying approximately 261,321 properties. The drinking water

network is also comprised of 55 pump stations and 58 reservoirs with a total capacity of approximately 400 ML,

and 3 re-chlorination stations.


Molendinar WTP supplies

directly to: Southport West.

Grab Sample Monitoring.

Mudgeeraba WTP

supplies directly to:

Currumbin, Coolangatta,

Mudgeeraba, Reedy

Creek, Burleigh &

Elanora.

Molendinar Reservoirs fed from Gold Coast DP,

Molendinar WTP and Mudgeeraba WTP.

Supply to: Molendinar, Nerang South, Nerang, Gaven/

Coomera, Helensvale, Pimpama/Coomera, Worongary,

Gilston, Stapylton/Yatala & Beenleigh.


Online

Online Monitoring - turbidity,

free chlorine, pH & conductivity.

Chloramination Facility (Beenleigh)

Owned and operated by Logan City

Rechlorination Facilities Jacobs Well

for GCW Northern Area.


Not in scope

of this

management

plan.

SRWP Offtakes

Helensvale, Ormeau,

Pimpama.

Online

Dual Reticulation

Drinking & Non-Drinking Water

Pimpama- Coomera.

Gold Coast DP + Mudgeeraba

mix through SRWP to supply:

Robina (under normal

circumstances) Can also

supply Worongary and Gilston

if required however is not the

current operation.


Molendinar WTP Mudgeeraba WTPGold Coast DP

SRWP

Online

Non-Drinking Water

Reservoir (Peanba Park)

Non-Drinking Water Top-up

Not in Scope of this

management plan.

This area is under the scope of the following upstream providers’

DWQMPs:

- Seqwater

This area is under the scope of the following

downstream providers DWQMP:

- Logan City Council

Pacific Ocean Hinze Dam

Process

Transport

Monitoring

Storage

Key

Bulk Water Supply

Tweed Shire

Council

emergency use

only. Not in the

scope of this

management

plan.

Rechlorination Facilities

Mt Nathan and Gilston

Grab Sample Monitoring

Little Nerang Dam

Raw water

customers

Figure 1: Catchment to consumer schematic of the Gold Coast drinking water distribution system.


5. Compliance with water quality criteria

5.1 Overview of water quality monitoring program

GCWW undertakes both operational and verification monitoring across the drinking water network to ensure the

provision of safe and reliable drinking water to our customers. Water quality is tested at 112 fixed sample sites

across the drinking water network. The parameters that are monitored have been selected based on the risks

identified in the DWQMP. Additionally, continuous water quality monitoring of key disinfection parameters

occurs at strategic locations throughout the system.

5.2 Summary of water quality compliance

As part of complying with section 95(3)(g) of the Act, GCWW is required to undertake verification monitoring of

drinking water quality as specified in the DWQMP and approved by the Regulator. To determine compliance the

drinking water quality verification monitoring results are assessed against the following:

The standards for the quality of drinking water prescribed in a regulation under the Public Health Act 2005;

All parameters that have health guideline values in the ADWG;

Water quality criteria stated in the Water Quality and Reporting Guideline for a Drinking Water Service.

In 2019-20 there were two instances of noncompliance with the water quality criteria for the drinking water

system. These were identified during ad hoc sampling in response to customer complaints and were not part of

the verification monitoring program. The details of the noncompliance are summarised in table 1 and described

in further detail in section 6.

Table 1: Summary of water quality noncompliance events 2019-20

Date Location Parameter Result ADWG Limit

29/08/2019 Mudgeeraba Benzene 0.0016 mg/L <0.001 mg/L

10/06/2020 Arundel Benzene 0.029 mg/L <0.001 mg/L

The water quality data for 2019-20 has been summarised in Appendix A. The reported statistics do not include

results derived from repeat samples, or from emergency or investigative samples undertaken in response to an

elevated result, as described in the ADWG (2011) section 10.3.1. Furthermore, data used to calculate the 12

month ‘rolling’ annual value for E. coli has been presented in Appendix B. A microbial compliance of 100% was

achieved during 2019-20. An annual water quality summary is provided on the City’s website

(www.goldcoast.qld.gov.au) for customers.



6. Notifications to the Regulator under sections 102 and 102A of the Act

In the 2019-20 FY there were two instances where the Regulator was notified under sections 102 or 102A of the

Act. These notifications involved the detection of benzene from the customer’s water meter whilst investigating

taste and odour enquiries. These detections were made during ad hoc sampling and were not a part of the

routine verification monitoring.

6.1 Non-compliances with the water quality criteria and corrective and preventive

actions undertaken.

Detection of benzene – Rainbow Drive, Mudgeeraba 6.1.1

Incident Description

On 29 August 2019, whilst investigating a taste and odour enquiry at two properties on Rainbow Drive,

Mudgeeraba, samples were collected from internal plumbing, property water meters and nearby hydrants.

Analysis results showed that BTEX compounds were detected from the samples collected on the properties as

well as the water meters, these compounds were not detected in the nearby hydrants. Benzene was detected at

a concentration of 0.0016 mg/L which is above the ADWG health guideline value of <0.001 mg/L. It was noted

during the investigation that a vehicle was parked over the area where the water service lines enter the

properties with evidence of oil or fuel spillage on the gutter and the road.

Corrective and Preventive Actions

Immediately upon notification of the ADWG exceedance the incident management procedures were activated.

Customers at both properties were notified immediately and informed to avoid using the water until the issue

was rectified. They were supplied with bottled water during this time until repairs were completed. Civil

Maintenance crews attended the site and excavated and removed all of the soil around the affected area. The

polyethylene service connections from the water main were replaced with copper to prevent further

contamination, as were the impacted water meters. Additional sampling was undertaken over the following

weeks to confirm that the issue had been resolved.

The investigation concluded that the likely cause of the issue was a fuel or oil spillage from a vehicle parked on

the nature strip over the area where the service connections were. To prevent this happening again in the future

the customers were informed that they should park their vehicles in the driveway and were also given

information regarding the risks of fuel spillage around the property.

Detection of benzene – Wepham Court, Arundel 6.1.2

Incident Description

On 10 June 2020, whilst investigating a taste and odour enquiry at two properties at Wepham Court, Arundel,

samples were collected from internal plumbing, property water meters and nearby hydrant. Analysis results

showed that BTEX compounds were detected from the samples collected on the properties as well as the water

meters, these compounds were not detected in the nearby hydrant. Benzene was detected at a concentration of

0.029 mg/L which is above the ADWG health guideline value of <0.001 mg/L. It was noted during the

investigation that a boat was parked over the area where the water service lines enter the properties with

evidence of oil or fuel spillage on the ground where the water meters and service lines were located.

Corrective and Preventive Actions

Immediately upon notification of the ADWG exceedance the incident management procedures were activated.

Customers at both properties were notified immediately and informed to avoid using the water until the issue


was rectified. They were supplied with bottled water during this time until repairs were completed. Civil

Maintenance crews attended the site and excavated and removed all of the soil around the affected area. The

polyethylene service connections from the water main were replaced with copper to prevent further

contamination, as were the impacted water meters. Additional sampling was undertaken over the following

weeks to confirm that the issue had been resolved.

The investigation concluded that the likely cause of the issue was a fuel or oil spillage from a boat parked over

the area where the service connections were. To prevent this happening again in the future the customer was

informed that they should park the boat in an area away from the water infrastructure and both customers were

also given information regarding the risks of fuel spillage around the property.


7. Customer complaints related to drinking water quality

GCWW carefully monitors and investigates customer complaints relating to drinking water quality. Under section

142(3)(g) of the Act, it is a requirement of GCWW to report on the number of customer complaints, general

details of complaints, and the responses undertaken. Throughout the 2019-20 FY a total of 258 complaints were

received relating to the quality of the drinking water supplied, equating to 0.97 complaints per 1000 connections.

Table 2 provides some additional detail about the nature of the drinking water quality complaints received.

Table 2: Summary of customer complaints for drinking water quality

Scheme Suspected illness Discoloured water Taste and odour Total

Gold Coast 25 126 110 258

GCWW classifies customer complaints into three categories; those that relate to the appearance of the water

such as discolouration; those that relate to taste and odour of the water; and those where the water is

suspected to be causing a health issue. GCWW has operational procedures in place, as part of the drinking

water Hazard Analysis and Critical Control Points (HACCP) Plan, for dealing with dirty water, taste and odour or

illness related enquiries. All customer complaints are reviewed thoroughly by Product Quality and acted upon as

necessary.

Suspected illness: Complaints are sometimes received from customers who suspect their water may be

associated with an illness they are experiencing. GCWW investigates each complaint relating to alleged illness

from our water quality, typically by testing the customers tap and closest reticulation sampling point for the

presence of E. coli. During the 2019-20 FY, there were no confirmed cases of illness arising from the water

supply system. All testing for suspected illness enquiries indicated that the drinking water quality met the

required specifications.

Discoloured water: 126 customer complaints were received by GCWW in 2019-20 related to dirty or

discoloured water. Complaints in this category are primarily the result of sloughing of sediments in the water

mains, or white water due to the presence of air in the water mains. Generally these issues are able to be

resolved quickly through operational corrective actions such as flushing.

Taste and odour: Taste and odour water quality enquiries varied widely based on customer’s perception. The

most common complaint descriptions included chlorine, metallic and chemical tastes. Often when customers

receive water from a different source (i.e. desalinated as opposed to dam water) the change in taste is

noticeable. In 2019-20 GCWW received 110 taste and odour complaints. All taste and odour complaints are

investigated by Product Quality and laboratory testing is undertaken when deemed necessary.


8. Actions taken to implement the DWQMP

8.1 Progress in implementing the risk management improvement program.

The risk associated with low disinfection residual in reservoirs and the distribution system has been reduced to

an acceptable level through the mitigation measures that have been implemented. Despite this however,

disinfection improvement across the drinking water system is a key ongoing initiative for GCWW. In 2019-20

GCWW continued to implement the recommendations of the Disinfection Improvement Project which included:

Installation of mixers (with online chlorine monitoring) in three reservoirs (RW2, RW7, RNG1);

Continued optimisation of operating levels in supply reservoirs;

Finalisation of a project to install an additional 13 online water quality monitoring analysers across

the drinking water system

8.2 Revisions made to the operational/verification monitoring program to assist in

maintaining the compliance with water quality criteria in verification monitoring.

The frequency and scope of the verification monitoring program as described in the approved DWQMP has not

been changed since the last review in January 2020. As described in the DWQMP additional operational

monitoring has been added to the GCWW drinking water system. GCWW now operates 16 online water quality

monitoring stations at strategic locations across the drinking water network. This will be increased to 29 during

the 2020-21 FY. These analysers are monitored by Product Quality and the 24 hour Operations Centre

providing increased surveillance of drinking water quality across the city.


9. Outcome of the review of the DWQMP and how issues raised have

been addressed

An internal review of the DWQMP was undertaken in January 2020 and completed before 30 June 2020 as per

the requirements of Condition 10.1 of the Information Notice for the Decision. The purpose of the review is to

ensure that the plan remains relevant with regard to the operation of the drinking water service. The review and

subsequent amendments to the DWQMP were undertaken internally by staff in the Product Quality section.

Upon completion the DWQMP was reviewed and approved by the GCWW Director and Management team and

was submitted to the Regulator for review.

The amendments made to the plan are summarised below:

Table 3: Summary of changes to DWQMP following review in 2020

DWQMP Section Description of Change

Registered service details Updated data on population, service connections and water demand

Details of infrastructure providing the

service

Updated schematics to reflect changes in the drinking water network, removed reference to

PA5 re-chlorination station following decommissioning

Updated figure to include recently added online monitoring locations

Updated information on reservoirs, pumps, water mains and disinfection stations

Updated details for bulk supply points to reflect information in the Operating Protocols

Updated position details of key personnel involved in management of water quality

Identification of hazards and

hazardous events Updated historical water quality data to include previous 2 years

Assessment of risks No change

Management of risks Added detail explaining the role of the City’s Corporate Cyber Security Team

Operational monitoring

Added details of new online water quality instruments installed to provide better operation

monitoring of the system

Updated information about customer complaint monitoring

Verification monitoring Updated information to include more detail for each verification monitoring site

Updated information on sampling frequency and the number of sites

Appendix 1 Updated mapping of the drinking water infrastructure

Appendix 2 Water quality trends have been updated to include most recent data values

Appendix 3

Updated risk assessment to include information on managing risks associated with cyber

security

Included the installation of reservoir mixers at 3 sites to the risk controls for reservoir

storage

Appendix 4 Minor changes were made to the structure of the GCWW Drinking Water HACCP Plan

Appendix 5 The list of operational procedures has been updated with all procedures that have been

withdrawn removed from the list


DWQMP Section Description of Change

Appendix 6 The GCWW QP-19 Issue Management Plan has undergone significant review and

redevelopment to improve the process of incident management

Appendix 7 Minor cosmetic changes to procedure

Appendix 8 Minor updates to document to reflect current operation

Updated non-drinking water quality data summary


10. Findings and recommendations of the DWQMP auditor

No audit was conducted during the reporting period 1/7/19 to 30/6/20. As per the requirements of Condition 10.2

of the Information Notice for the Decision the next scheduled external audit of the GCWW DWQMP is to be

complete by 21 April 2021.


11. Appendix A

Table 3: 2019 – 2020 verification monitoring results

Parameter Min Max Ave 95%ile Count # Exceed

ADWG Units LOR # Detects Laboratory

Scheme Component

ADWG Value

Health or Aesthetic

Alkalinity 36 78 46 67 78 0 mg/L (CaCO3/L) 2 78 GCW-SS R 0 No Guideline

Aluminium 0.006 0.077 0.017 0.032 233 0 mg/L 0.005 233 GCW-SS R 0.2 Aesthetic

Ammonia 0.003 0.329 0.008 0.003 76 0 mg/L 0.006 2 GCW-SS R 0.5 Aesthetic

Arsenic 0.0005 0.0005 0.0005 0.0005 76 0 mg/L 0.001 0 GCW-SS R 0.01 Health

Asbestos 0 0 0 0 20 0 0 GCW-SS R 0 No Guideline

Bis (2-Ethylhexyl) Phthalate 0.005 0.005 0.005 0.005 20 0 mg/L 0.01 0 GCW-SS R 0.01 Health

Boron 0.003 0.42 0.057 0.319 88 0 mg/L 0.03 25 GCW-SS R 4 Health

Cadmium 0.0005 0.0005 0.0005 0.0005 76 0 mg/L 0.001 0 GCW-SS R 0.002 Health

Calcium 10 23 16 20 126 0 mg/L 1 126 GCW-SS R 0 No Guideline

Chlorine Free 0.025 2 0.91 1.40 2206 0 mg/L 0.05 2201 GCW-SS R 5 Health

Chromium 0.0005 0.001 0.0005 0.0005 76 0 mg/L 0.001 0 GCW-SS R 0 Health

Conductivity 0.16 0.552 0.233 0.490 522 0 mS/cm 0.03 522 GCW-SS R 0 No Guideline

Copper 0.0005 0.008 0.002 0.005 76 0 mg/L 0.005 6 GCW-SS R 2 Health

E. coli 0 0 0 0 2206 0 cfu/100mL 1 0 GCW-SS R 0 Health

Fluoride 0.05 1.2 0.78 0.90 312 0 mg/L 0.1 311 GCW-SS R 1.5 Health

Hardness 33 100 51 81 126 0 mg/L 1.3 126 GCW-SS R 200 Aesthetic

Iron 0.01 0.08 0.012 0.020 76 0 mg/L 0.01 76 GCW-SS R 0.3 Aesthetic

Lead 0.0005 0.001 0.0005 0.0005 76 0 mg/L 0.0005 1 GCW-SS R 0.01 Health

Magnesium 1.1 11 2.7 7.6 126 0 mg/L 0.5 126 GCW-SS R 0 No Guideline

Manganese 0.0005 0.069 0.0008 0.002 2206 0 mg/L 0.001 474 GCW-SS R 0.5 Health

Mercury 0.00005 0.00005 0.00005 0.00005 292 0 mg/L 0.0001 0 GCW-SS R 0.001 Health

Nickel 0.0005 0.001 0.0005 0.0005 76 0 mg/L 0.005 0 GCW-SS R 0.02 Health

Nitrate as (NO3) 0.015 0.33 0.10 0.3 75 0 mg/L 0.006 75 GCW-SS R 50 Health

Nitrite Nitrogen 0.005 0.005 0.005 0.005 75 0 mg/L 0.01 0 GCW-SS R 3 Health

pH 6.9 8.8 7.60 7.90 2206 10 2206 GCW-SS R 6.5-8.5 Aesthetic

Plate Count 0 11000 8.80 2 2202 0 cfu/mL 1 212 GCW-SS R 0 No Guideline

Silica 8 12 10.24 11.55 10 0 mg/L 0.1 10 GCW-SS R 80 Aesthetic

Sodium 12 35 16.97 30.25 76 0 mg/L 0.5 76 GCW-SS R 180 Aesthetic


Parameter Min Max Ave 95%ile Count # Exceed

ADWG Units LOR # Detects Laboratory

Scheme Component

ADWG Value

Health or Aesthetic

Temperature 7.7 33.9 23.07 28.20 2206 0 °C 0 0 GCW-SS R 0 No Guideline

Total Coliforms 0 3 0 0 2206 0 cfu/100mL 1 4 GCW-SS R 0 No Guideline

Total Dissolved Solids 33 230 113 161 59 0 mg/L 1 59 GCW-SS R 600 Aesthetic

Total Trihalomethanes 0.032 0.17 0.09 0.13 250 0 mg/L 0.005 250 GCW-SS R 0.25 Health

True Colour 1 5 1.5 3 2206 0 HU 2 869 GCW-SS R 15 Aesthetic

Turbidity 0.1 8.7 0.28 0.48 2206 3 NTU 0.1 2206 GCW-SS R 5 Aesthetic

Zinc 0.0005 0.007 0.002 0.003 76 0 mg/L 0.01 0 GCW-SS R 3 Aesthetic


12. Appendix B

Table 4: E. coli verification monitoring results

Year 2019- 20

Month Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun

No. of samples collected 219 174 208 185 174 147 171 170 214 172 172 200

No. of samples collected in which E. coli is detected (i.e. a failure) 0 0 0 0 0 0 0 0 0 0 0 0

No. of samples collected in previous 12 month period 2173 2173 2209 2181 2188 2177 2140 2135 2178 2197 2179 2206

No. of failures for previous 12 month period 1 0 0 0 0 0 0 0 0 0 0 0

% of samples that comply 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100% 100%

Compliance with 98% annual value YES YES YES YES YES YES YES YES YES YES YES YES


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