Oireachtas Joint and Select Committees

Tuesday, 5 November 2019

Joint Oireachtas Committee on Housing, Planning and Local Government

Issues Affecting the Quality of Water: Discussion

Mr. Niall Gleeson:

My name is Niall Gleeson and I am the managing director of Irish Water. I am accompanied today by Michael O’Leary, head of asset operations, and Katherine Walshe, head of environmental regulation. I thank the Chairman, Deputy Rock, and the committee members for the opportunity to address them.

I apologise to affected customers for the inconvenience caused by both the previous and the current boil water notices. I welcome the opportunity to explain to the committee how the events happened, what actions we have taken and how we, along with our colleagues in Fingal County Council, intend to mitigate the risk of such events happening in future. As the committee heard from the EPA, there are two plants in Leixlip, an old plant and a new plant. As discussed, we have had problems with the old plant and are currently upgrading it. It is where the problem occurred at the weekend. The prolonged heavy rain on Saturday night presented issues with turbidity, or cloudiness, and the old plant could not treat the water to the required standard. In fairness to the plant operators, on this occasion they reacted quickly. They saw the alarms, kicked in and shut down the plant, preventing untreated water from entering the system. They spent most of Sunday and Monday morning trying to return the old plant to service, using a wastewater discharge, which allows the plant to be run but to waste rather than into the system.

Unfortunately, this was not successful and our reservoirs throughout the city were running low. We had to make the decision that rather than have water restrictions, where people would not have had water for flushing toilets, showering or washing, we would reintroduce the water with whose treatment we were not happy, while at the same time issuing a boil water notice. It was a conscious decision taken over the weekend, and it is important to emphasise the difference between the incident in question and the previous incident. The Fingal County Council operators acted correctly and Irish Water took a decision to introduce the water I have described because the only other option was to introduce water restrictions.

To end the current boil water notice, as was discussed with the EPA, satisfactory water quality tests will be needed. The first sample was taken today and we will continue in that regard during the week. On EPA confirmation that the plant is operating satisfactorily, unfortunately the plant is still not delivering the levels of treated water we would like. It is still delivering cloudiness outside the limits set by the EPA and us, which is unfortunate but we are working as hard as possible to correct the problem. It is not a plant failure or the result of a particular incident rather it concerns the filter beds we are currently trying to refurbish. As soon as we are happy that the water entering the system is of good quality, we can start the clock and flush the slug of water through the system. That is the current position.

Irish Water has a comprehensive compliance monitoring programme in place for every public water supply in the country to ensure that drinking water quality is adequately monitored and complies with legislation.

Since Irish Water was established in 2014, we have significantly improved water quality monitoring on public drinking water supplies. More rigorous sampling regimes have been put in place, for example the number of tests for cryptosporidium and giardia doubled from approximately 800 in 2014 to more than 1,500 in 2018.

The EPA and HSE, who have responsibility for regulating drinking water quality and protecting public health respectively, now have a single point of contact for all water quality issues nationally. Water quality risks and failures are identified sooner, corrective action can be taken quickly, and the risk to public health from poor water quality has been reduced significantly. Of course, we have more work to do in this area.

The quality of public drinking water in Ireland remains high with microbiological compliance at 99.87% and chemical compliance at 99.63%, as outlined in the 2018 EPA drinking water quality report.

All drinking water must be treated before being consumed to remove biological and chemical contaminants that can be harmful to human health. Bacteria from animal or human waste and parasites such as cryptosporidium and giardia are commonly found in open water bodies such as the River Liffey. These organisms can cause gastrointestinal illness in humans.

Following consultation with the HSE, a boil water notice is imposed where water treatment may be inadequate to eliminate the risk of illness from microbiological contamination. There are currently 17 boil water notices in place nationally impacting on approximately 14,000 people. The largest is on Lough Talt in Sligo, affecting 12,500 people, where there is a risk of cryptosporidium contamination. The majority of the other boil water notices relate to areas where treated water requires additional disinfection contact time, a problem identified through Irish Water’s national disinfection programme. Due to work under way by Irish Water, four of the 17 notices are on track to be lifted this year, with most of the others, including Lough Talt, on track to be lifted in 2020.

The greater Dublin area, GDA, drinking water supply serves all of Dublin and parts of Kildare, Meath and Wicklow. Drinking water in the GDA is supplied from a number of sources, predominantly the River Liffey, which accounts for 85% of the supply to Dublin, and the River Vartry. Water is produced in Dublin on a 24-hour basis and the total water production capacity is 612 megalitres per day, which can reduce to 580 megalitres due to weather, drought or algal blooms, for example. Demand for water in the GDA varies but the average daily demand is 570 megalitres per day, increasing to 600 megalitres per day at times of high demand. Headroom or spare capacity in available water in Dublin is, therefore, between 10 and 40 megalitres per day. That is important in the context of the old plant, which is having problems and which produces in the region of 20% of Dublin's water supply.

Leixlip water treatment plant, WTP, is the second largest water treatment plant in Ireland; the largest is at Ballymore Eustace. Leixlip WTP supplies treated drinking water to more than 600,000 people in Dublin, Kildare and Meath, approximately one third of the greater Dublin area, including healthcare facilities, industry and many large commercial customers. Leixlip WTP is operated by Fingal County Council under a service level agreement with Irish Water.

Leixlip WTP currently produces 195 megalitres per day of treated drinking water, with a maximum production of 210 megalitres per day. Due to the phased expansion of Leixlip WTP since it first opened in 1967, current operations on the site are carried out across a number of plants known as the old plant, built by PCI in the 1970s and upgraded by McMahon Philips in the 1990s, and the new plant, built by AECOM in 2014. These are separate plants and there is not a continuous upgrade process on the old plant. The old plant produces two thirds of the water at Leixlip.

In 2019, there have been ten low level detections of giardia and one detection of cryptosporidium in treated water at Leixlip. These test results were reported to the EPA and the HSE and not deemed to be an immediate risk to public health. Given the detections, in consultation with HSE, Irish Water doubled its monitoring programme for cryptosporidium and giardia at the plant in 2019.

We have also taken special interest in the operation of the filter beds in the old plant because if the filter beds are not meeting the levels required and there are instances of giardia, there are increased concerns. We are currently upgrading the filter beds in the old plant and ideally we would take the plant out of service for a six-month or 12-month period to complete all the works and bring it back into service thereafter.

Ideally we would take this plant out of service for a period of six to 12 months, complete all the works and then bring it back into service. However, because it supplies 20% of Dublin's water and because we cannot switch it off as we do not have any backup supplies, we have to do this work on an ongoing basis. The plant needs to remain operational at all times. This is akin to trying to change the tyres on a car while it is moving down the road. It is a very difficult process and has led to some delays, which the EPA highlighted.

In March 2019, there was a mechanical failure of a chemical dosing pump at the new plant. An on-site alarm was triggered but was not responded to. The incident was reported at the time to the EPA and the HSE, which did not consider the failure to be a risk to public health. Water produced remained safe. The EPA conducted an audit of the new plant on 22 March. Following recommendations made by the EPA in its March audit, the automatic shutdown requested by it was completed in the new plant. A contract was issued to install automatic shutdown at the old plant but this work had not been completed when the incident occurred on 22 October.

On Monday 21 October, a mechanical failure occurred on a piece of equipment at the old plant at Leixlip. I will describe the events in more detail. At 3.15 p.m. a blockage occurred in a chemical delivery line leading to a failure of a pressure-release valve. No pump alarm activated as the failure point was downstream of the pumps. At 5 p.m., turbidity levels in filtered water started to increase as a result of the delivery line failure. Turbidity is cloudiness in water due to suspended particles. At 6.16 p.m., increasing turbidity in filtered water triggered an on-site alarm and sent an SMS text alert to the operators. The alarm was not responded to and turbidity continued to rise. At 7.07 p.m. an on-site high-turbidity alarm was activated on the clarified water. The alarm was not responded to and turbidity continued to rise. At 9.15 p.m., an off-site plant manager who had logged on remotely to the Leixlip plant noticed the activation of turbidity alarms and the lack of response on site. The alarm was investigated and a contractor was called to clear the pipe blockage and carry out temporary repairs. From 10.15 p.m. to 11.30 p.m., the repair was completed. A decision was taken to shut down the old plant temporarily to allow the treatment process to stabilise. Between 11.30 p.m. and 5 a.m. on Tuesday, 22 October, the old plant was gradually brought back into operation. The automatic plant shutdown did not happen when the alarms were not responded to because we had not yet put this facility in place.

The new plant at Leixlip continued to produce drinking water that met all drinking water quality standards while the incident was ongoing at the old plant. However as the drinking water produced at both plants is mixed when it enters the network, all areas supplied by the Leixlip plant were subject to the boil water notice. Irish Water was first notified of the incident at the old plant by Fingal County Council at 9.45 a.m. on Tuesday, 22 October. We immediately contacted the HSE and EPA. We were in discussions with them throughout the day sharing data, reviewing the plant performance data and determining the level of risk to public health arising from the incident. Following the consultation, a decision was taken at 4.30 p.m. on Tuesday, 22 October to impose a boil water notice on customers supplied by Leixlip wastewater treatment plant. The Irish Water crisis management team, which was on standby, formally convened at 5 p.m. and the notification of customers began immediately. Irish Water's foremost priority throughout the period of the boil water notice was to protect public health and to advise all customers as quickly as possible. The first task of the team was to issue widespread communications with immediate effect. Given the number and geographic spread of customers affected, multiple communication channels were used, with emphasis on mass communication and prioritising proactive contact with vulnerable customers and large water users.

A press release with detailed advice and information and a map of the affected area was issued to national media in time for the 6 p.m. news on Tuesday, 22 October. This information was posted on our website and on social media channels and briefed to our customer contact centre. We directly contacted our registered vulnerable customers and an email went to elected representatives in the affected areas. We contacted large commercial and industrial customers and worked with stakeholders to identify critical users such as hospitals, schools, nursing homes and crèches. Engagement with customers, stakeholders and media continued through Wednesday, Thursday and Friday. A more detailed interactive map of the areas affected was posted on the website and shared widely. Further details of customer communications are provided in the appendix to my written statement. I thank the media, elected representatives, local authorities, business and industry groups, Departments and all who extensively and proactively shared our advice to customers while the boil water notice was in place.

Irish Water's website experienced difficulty on Tuesday, 22 October due to very high volumes of traffic to the site. Our IT teams worked throughout Tuesday evening to rectify the situation and, by Wednesday morning, the website was fully operational.

Our IT teams worked throughout Tuesday evening to rectify the situation and by Wednesday morning the website was fully operational. This was clearly not satisfactory and we are working to ensure that the site can cope with high volumes in future. During this more recent boil water notice, it has been able to handle the increased volumes.

On the lifting of the boil water notice, on Wednesday, 23 October Irish Water sought to identify clear criteria for lifting the boil water notice as quickly as possible while still ensuring no risk to public health. Lifting criteria agreed with the HSE and the EPA were as follows: satisfactory sample results for giardia and cryptosporidium; a satisfactory EPA audit of the old plant; and confirmation that all remaining at-risk water had passed through or was removed from the network. The result of the first sample covering the period of the incident was available on the morning of 24 October and water quality was satisfactory. Results of the second and third drinking water quality samples taken on 22 and 23 October were returned on Friday, 25 October and these samples were also satisfactory. The EPA inspectors carried out an audit of the Leixlip plant on Thursday, 24 October, accompanied by the HSE, Irish Water and Fingal County Council. Initial feedback from the EPA inspectors at the site indicated they were satisfied from a technical perspective that the boil water notice could be lifted. The final audit report from the EPA was issued on 30 October. On the network flushing side, Irish Water carried out extensive network modelling to work out how much of the water produced at Leixlip on 21 and 22 October was still in the network. Proactive flushing was carried out by Fingal County Council on Friday, 25 October to remove any remaining at-risk water from the extremities of the network. Irish Water continued discussions with the HSE and the EPA during Friday, 25 October to ensure all criteria agreed were met to allow the boil water notice to be lifted. The HSE confirmed at 4.30 p.m. that it was satisfied that the boil water notice could be lifted and this was communicated immediately and as widely as possible to all customers and stakeholders through all available communication channels.

The following immediate actions have been taken. Throughout the incident, Irish Water and senior Fingal County Council staff have been in contact with each other. The discussions are ongoing and we are trying to prevent the last and current incidents from happening again. The Leixlip water treatment plant is already staffed on a 24-hour basis and Irish Water has requested that Fingal County Council increase staffing at the plant to ensure an appropriate level of vigilance and eliminate the risk of an alarm not being responded to in future. Irish Water will work with Fingal County Council to agree more on-site presence by Irish Water staff at the Leixlip water treatment plant. Irish Water is looking at all potential enhancements to operations that will further safeguard water quality at Leixlip water treatment plant and all other large plants nationally. Automatic shut-off at the old plant is now operational. It is worth highlighting that automatic shut-off should be the option of last resort in a plant with 24-hour staffing as alarms should be responded to and a shut-off takes the plant completely out of production. Shutting down and restarting a water treatment plant brings its own risks and given Dublin’s lack of headroom, this could also present supply challenges which we are experiencing at the moment. Irish Water is in the process of bringing all critical alarms nationally into our national operations centre. For this to be beneficial, however, Irish Water needs to be able to contact plant operators directly when an alarm is triggered. This is not part of the current working arrangements. Irish Water is carrying out a review of the filter upgrade programme under way at the old plant to expedite its completion, bearing in mind the current water supply headroom challenges.

The recent incident at Leixlip caused significant disruption to customers and is not acceptable to Irish Water. That goes for the current incident as well. Our priority is to provide a safe, secure drinking water supply and we accept responsibility for this incident. We will continue to notify the EPA and HSE of any reportable incidents as soon as we are aware of them. We are working with Fingal County Council to take all necessary steps to reduce the risk of an incident like this happening again.

Irish Water is preparing a detailed written response to the issues raised by the EPA following its recent audit. At the time of the incident auto shut-off had been installed at the new plant and was in the process of being installed at the old plant. It should be reiterated that auto shut-off is an option of last resort. A plant of this size cannot be reliant on the sole response of individuals. The incident highlights the fact that we must use all available technology to prevent a failure like this happening in future. Under the current working arrangements this is not possible. Filter beds in the old plant are being upgraded.

This work started in 2018 and will be completed by the second quarter of next year. Any acceleration of this work must be balanced with the need to maintain sufficient water supply to the greater Dublin area.

Irish Water is fully committed to the Workplace Relations Commission process, initiated by the Minister and now under way, to replace the current service level agreements, SLAs, with local authorities with arrangements which will provide Irish Water with the necessary full control of operations, accountability and capacity to manage risk and provide a single identity for customer-facing services. Completing that process is likely to take some time and we believe that several operational issues must be addressed in the interim, under the current SLA, to reduce current risks to the provision of safe and reliable water services to our customers. I thank the committee members for their time. I will take any questions they wish to raise with me or my colleagues.