Agenda item

To receive an update from Thames Water on the progress of Multi Agency Flood Planning.

Councillor Conneely welcomed Alex Nickson, Water Resources & Growth Lead, Thames Water to the Committee to share his report that updated the Committee on the progress of Multi Agency Flood Planning.

The following key points were discussed:

·                 Surface water flood risk was recognised as an increasing concern across London, owing to a number of factors that included loss of permeable surfaces to impermeable surfaces, a sharp growth in regeneration across London and climate change. The cumulative impact of these factors had created pressure on the drainage network across London with the historic infrastructure not able to cope with the additional pressures, resulting in more frequent flood events in London.

·                 Flood risk across London was highlighted in July 2021 after London experienced two 1 in 200 year flood events within a fortnight.

·                 Following the flood events, Thames Water (TW) commissioned an independent London Flood Review (LFR) to gain a greater understanding of why the flooding in July 2021 had been so severe, whether TW’s assets had exacerbated the flooding and to make strategic level recommendations on how to manage the increasing risk with a collaborative response and action plan.

·                 Following the recommendations made by the LFR (as detailed within Appendix 1 of the TW report provided for the Committee) and the Mayor’s Surface Water Roundtable the London Surface Water Strategic Group was created to provide a high level strategic overview to support collaboration with a range of agencies to produce and deliver a London Level Surface Water Management strategy and action plan. This would run parallel to TW’s Drainage and Wastewater Management Plans (DWMP).

·                 The Committee were advised that there was no one factor identified to resolve all the issues contributing to surface water flooding in London at present, however with effective risk management and a number of different interventions it was felt that risks could be mitigated to limit the impact of flooding in London, parallel to longer term plans being made to futureproof London’s drainage network.  The interventions identified included finding ways to increase sewer capacity, reducing the volume of floodwaters getting into the sewer and greater information sharing across boroughs to understand how issues up or down stream were impacting upon specific locations.

·                 In order to reduce the volume of floodwaters getting into the sewers the Committee heard that increased use of Sustainable Urban Drainage Systems (SuDS) features, including the use of rain gardens and water butts, was seen as positive step forwards in reducing surface water run off. It was, however, acknowledged that residents may need to be incentivised to use water butts and the addition of rain gardens would need to be funded.

·                 Members were also advised of the ongoing work being undertaken by TW designed to support an increase in the capacity of the sewer network.

Alex Nickson ended his introduction by assuring the Committee of TWs commitment to collaborative working with the Local Authority to effectively manage surface water and sewer flooding.

Councillor Conneely thanked Alex Nickson for his report before asking the Committee if they had any questions in relation to the information heard, with the following points discussed:

·                 In referencing the severity of some specific localised flooding events, the Committee queried whether increased numbers of residents using water butts would provide a significant mitigation. In response the Committee were advised that although the impact may initially be minimal, the addition of water butts provided a good starting point in reducing the volume of local surface water run off during periods of heavy rainfall.

·                 In relation to a query regarding the impact of heavy rain and flooding on pedestrian access to footpaths the Committee were advised that the increased use of SuDS would provide a betterment to the existing situation in specific locations. To optimise the use of SuDS it would be necessary to work alongside the highways team to assess if the current infrastructure was meeting the needs of the area and, if not, what type of SuDS intervention would be most effective in reducing the volume of surface water run off. It was highlighted that consideration should be given to identifying key geographical points where interventions could be actioned to provide the greatest impact.

·                 The Committee questioned how the suggested mitigations would be funded. Alex Nickson advised that TW were funded by customers and incentivised through performance commitment processes to deliver challenging targets as set by Ofwat.  In order to support the level of work required to enhance the level of effective flood management activity a co funded effort between local authorities and water companies as outlined in TW’s 5 year business plan would be necessary.

·                 The Committee raised concerns that Brent residents were frequently being impacted by the increased flooding and leaks across the borough and questioned whether this could be a result of poor connections, specifically push connections being used to replace push and screw connections.   Additionally it was queried if the replacement manhole covers being rolled out were fit for purpose as residents had shared that there appeared to be disruption when vehicles went over them. Alex Nickson advised that he was unaware of the specific issues raised, however would seek feedback from colleagues and provide a response to the Committee when the information was available.

·                 The Committee was advised that the increased use of water meters had provided valuable information in pinpointing locations where leak levels were high and/or frequent. This had supported TW to target leaks more effectively. The intelligence gathered also supported forecasting where future burst pipes may occur.

In response to a query in relation to the sewer and gully cleaning programme, officers advised that a cyclical programme using intelligence on silt levels in each of the gully’s was used to prioritise cleaning locations. The Committee heard that dependant on the levels of silt collection, gullies were cleaned approximately between every 6-18 months. It was established that the Council and TW shared responsibility for the gully and sewer cleaning programme, with the Council responsible for street cleaning and the cleaning of the gully pot, TW were responsible for cleaning from then gully down to the sewer. It was felt that going forward the cleaning of the gully and sewer system would be most effective if completed in unison. In response, TW advised of a pilot scheme already in development to trial a cohesive approach to gully cleaning with individual local authorities in order to identify the most productive, thorough and cost effective approach moving forward, which would also be open for Brent to participate in

·                 Chris Whyte, Director of Environment and Leisure advised that in addition to synchronising gully and sewer cleaning, consideration should be given to a parallel reactive response necessary to manage high foliage debris in the Autumn that was often exacerbated by changing weather conditions and therefore more challenging to plan for.

·                 In terms of the ongoing maintenance of the sewer network, TW confirmed that a rolling programme known as the Victorian Mains Replacement Programme continued to be rolled out to replace old pipes with a view to reducing leaks from the pipe network.

·                 The Committee queried the impact of the role of TW in local planning applications. TW advised that, whilst not statutory planning consultees, they would comment when consulted if it was felt that a development may cause additional pressure to the network,increasing flood risks.

·                 The Committee expressed concern at TW’s response in relation to their input on planning applications as in member’s experience of serving on Planning Committee’s they could not recall any applications where TW had made any other comment than “no objections”. It was highlighted that to support the Planning Committee in making informed decisions on applications in the future it would be helpful for TW to provide more considered responses to reassure the Committee that proposed schemes would not exacerbate existing issues or create new issues. Additionally, if TW believed that mitigations were necessary to support a scheme, this should be detailed in their response.

·                 The Committee shared concerns in relation to the level of support residents received from TW following a major flood event in Brent in December 2022 whereby some residents were left with no water or limited water pressure for a number of days following a burst main water pipe. In addition to this it was felt that the reactive response from TW had fallen below expectations in terms of delays in setting up bottled water stations and the limited accessibility in the locations of water stations. The Committee were advised that the incident in question had been a particular challenge to TW as it had taken longer than anticipated to isolate the valves due to access issues. Alex Nickson advised that the most vulnerable residents would have had water delivered directly to them, however acknowledged that they had fallen short of best practice in managing the incident and would therefore be seeking closer liaison with the Council in future in order to establish in advance the most suitable locations for bottled water stations to deliver more effective support to residents as part of a response plan if and when a future flooding event occurred.

·                 In relation to a follow up question regarding compensation for residents affected, Alex Nickson were unable to comment, however would seek to find the information and respond to the Committee following the meeting.

·                 In reference to a separate flooding incident in Brent in July 2021, the Committee raised what they felt was a poor response in relation to the communication provided to residents who called the TW contact centre for support and advice. Residents had reported that they were unable to get through on the phone and if they were successful in speaking to an operator, the operators were unable to advise or signpost appropriately. In response, Alex Nickson advised that call centre capacity had increased since the incident, it was acknowledged that the call centre had experienced issues with the capacity of calls received in July 2021, whereby they were receiving 4000 calls an hour in relation to the specific incident. TW had acknowledged their service did not meet expectations on that occasion, however since then the call centre capacity had increased and enhanced staff training had been delivered.

·                 The Committee questioned what was being done to reduce contamination in the River Brent following concerns raised regarding the presence of raw sewage impacting upon local residents and wildlife, specifically affecting an at risk species unique to Brent, the European Eel. The Committee were advised that TW took raw sewage contamination seriously and were committed to reducing this within their River Health Plan. Further exploration was underway to examine historic residential pipework in some parts of the borough where it was believed misconnections were contributing to leaking and cross contamination between foul water and surface water pipes.

·                 Joseph Barnett, Principal Engineer, Drainage and Structures (Brent Council) raised a further concern that the River Brent was severely affected by misconnections and issues upstream in the neighbouring borough of Harrow. The Committee noted that on occasions of heavy rainfall sewers overflowed and their contents were discharged into the River Brent. It was understood that as part of TW’s Drainage and Wastewater Management Plan an attenuation scheme of works were scheduled in Byron Recreation Ground in Harrow to support resolving the issues affecting Brent downstream.  In response, the Committee requested a timeline of when this work would be completed, which it was agreed would be provided once available.

As the Committee had no further questions for officers or Thames Water to respond to, the Chair went on to summarise the concerns that the Committee had in relation to Thames Water taking their responsibility seriously in managing the issues raised previously and during the Committee meeting. In sharing appreciation that Alex Nickson had attended the Committee to represent Thames Water, concerns were highlighted that engagement and the commitment towards collaborative working prior to his attendance had previously been below expected standards by Thames Water, which had been supported by their failure to provide the report for the Committee within the required timescales .The Committee had, however, welcomed the verbal responses provided during the meeting but felt that further assurances were still needed in order for the Committee to have confidence that Thames Water were committed to working with the Council to effectively manage the issues around surface water drainage and flooding in Brent. In view of the concerns highlighted, the Chair felt it would be important for Thames Water to provide the Committee with an action plan relating to the delivery of the recommendations identified in the LFR report.  On a positive note, the Chair ended by re-iterating the Committee’s thanks to Alex Nickson for attending and looked forward to increased accountability from Thames Water in the future.

The Chair thanked all those present for their contributions to the discussion before moving on to note the following suggestions for improvement and information requests:

Recommendations:

(i)              Thames Water and Brent Council to work together on a (Thames Water funded) pilot scheme of collaborative gully cleaning alongside a reactive leaf clearing programme that would readily respond at peak periods of heavy foliage debris during the Autumn.

(ii)             Thames Water to recognise their role as consultees on appropriate planning applications and encouraged to work with the Council in ensuring representations are submitted on proposed developments identifying mitigations required on relevant developments to ensure that flood risk was not increased.

Information Requests

(i)              Thames Water to provide further details regarding the change from push and screw connections to push connections and whether this could have affected efficiency and led to flooding/leaks.

(ii)             With regards to recommendation 3 in the London Flood Review (LFR), Thames Water to provide further information on how many planning applications they had commented on/objected/challenged/made a recommendation for additional mitigations to avoid flooding over the last 5 years.

(iii)           Thames Water to provide a detailed breakdown on the amount the organisation has invested financially in the borough of Brent over the last 3, 5, and 10 years; and specifically, what these investments have been made for.

(iv)           Thames Water to provide timescales on the Byron Park Recreation Scheme delivery.

(v)             Thames Water to provide the Committee with an action plan detailing the delivery of the recommendations identified in the London Flood Review report alongside a progress update.

(vi)           Provide a timescale of when Thames Water could return to the Committee to share an update of their 2025-2030 business plan and the London Level Strategy.

(vii)          Thames Water to provide detail on the investment in flood risk management in the Brondesbury Road area as this area had been prone to flooding.