Hellingly Flood Working Group Update
Meeting on Friday 19th January at 12.30pm
At Hellingly Community Hub, The Drive, Hellingly. BN27 3UY
Nus Ghani MP
David White - Hellingly Parish Council
Gill Hesselgrave - Hellingly Parish Council
Jenny Hoodless - Parish Clerk
Chris Bending - Wealden District Council (remotely)
Graham Keane - Wealden District Council
Mark Stapley - East Sussex Highways (remotely
Revai Kinsella - East Sussex County Council (remotely)
Nick Davies - Southern Water Programme Sponsor Wastewater Asset, Strategy and Planning
Joseph Whitehead - Southern Water Project Manager (remotely)
Martha - Southern Water
Alexandra Riordan - Southern Water (remotely)
Russell Paisy - Highways, Asset Manager
Paul Levitt - Environment Agency
Daniel Sargent - Environment Agency
- Nick Claxton, East Sussex County Council, Flood Risk Management
- Sue Cobb, Stakeholder Engagement Manager
- Russell Long, Environment Agency
- Claire Francis, Environment Agency
Cllr D White thanked everyone for all their efforts in answering the questions previously put to them and for attending today’s meeting.
SOUTHERN WATER (SW) COMMENTS:
1. SW had carried out a Connectivity Study for 581 address points in Hellingly and the report was over 4,000 pages long. This report is to be simplified and summarised, then email to the Clerk for circulation.
2. SW confirmed that Since December 2022 a number of activities have been kicked off to understand the root cause of the flooding in Station Road, the details are to be sent to the Clerk for circulation. They advised that the pumping station (PS) has not failed but is overwhelmed from the effects of surface water & ground water entering the system from the Hellingly area prior to reaching the PS. This is not caused by the river but the river levels mean that the pumping station cannot discharge through its permitted overflow. The investigations confirm the pumping station receives increased flow in heavy rainfall that it is not built to take, this is not just sewerage that enters the pumping station. As the area does not see flooding or hydraulic constraints in dry weather root cause is likely to be surface water inundation, misconnections and ground water infiltration. There is future growth in the area and all sites are yet to connect; the issues seen are not due to growth. The question was asked as to what was the maximum number of dwellings that could be joined to the PS in dry weather conditions. (In other words at what level of new connections would it become necessary to increase the capacity in the system). (SW to check and confirm)
3. SW confirmed that in November the South of England experienced storm Ciaran which resulted in the River Cuckmere bursting its banks. This was an extreme event that caused a failing of the drainage system. During this time they had operational support in the area to make sure they could reduce the impact as much as possible, they had confirmation that all but one AFD in Station Road was working, For the one that failed it was confirmed to be a electrical issue that has now been solved.
SW advised that the area served by the Station Road PS requires a pump and cannot be served by a gravity system alone. Pumping stations are typically situated close to a water course as these are the low points of drainage catchments. Given the nature of the Cuckmere River regardless of location the same issue of high river levels would occur and would simply shift the problem. The best solution is to remove the surface and ground water from the system. This is supported by EA Surface Water mapping and reports from on-site operatives that its current location is preferable to any area between its current location and B2104.
4. SW advised that as previously highlighted in the other questions; Hellingly is an area with a number of contributing factors to a complicated situation which requires work from all stakeholders. The immediate focus is in reducing the impact of foul flooding on the residents along Station Road. Through work with asset protection by the removal of surface water, misconnections and ground water. In the long term they are looking towards wider work in the Hailsham area that is in our PR24 plan that was submitted in October to OFWAT, more detail can be found on their website.
5. SW advised that an investigation to identify improvements had been completed and they had received the report just before Christmas this is now in review. Once they understand the report discussions will be instigated with the developer. Although they had now included Danecroft in their investigations, they had not been notified of the approval until the meeting held on the 5th December, until then they had only been notified that the application had been withdrawn. Given this they are approaching the developer to understand more of their plans and timelines of build out.
6. SW advised that given the construction on Sussex Plants was now well advanced, works are scheduled for completion by March 2025. Currently this timeline is reliant on the results of the connectivity survey, CCTV and Electroscan that are being reviewed by the team. The results will inform if there are any quick wins that can be completed alongside larger plans for the area. (What is the present number of consented connections? Originally it was to be limited to 69 without improvements to the system)
7. SW advised that the improvement works required to accept the foul flows from Park Farm East are scheduled for completion by March 2025, all developments along Station Road are encompassed in the same project.
8. SW advised that as a statutory consultee, they have no power past 24 months of outlined planning, to impose restrictions on developers to prevent further dwellings being added to the system prior to improvement. Prior to the 24 months where no capacity is seen, developments are responsible for their own sewerage disposal, after 24 months Southern water becomes responsible for this.
9. SW advised that Park Farm East West (Swingate Park dev) would be monitored as the developer has to keep moving the water around as the final connection had not yet been made.
SW confirmed they carry out inspections every 30 days of the pumping station and fix any issues found.
10. Southern Waters Report
Due to the nature of water it is hard to determine where if any single points of failure are, without modelling and surveying a wide area. This means there is not an easy fix due to the many contributing factors there is no single quick solution that one agency can complete, all agencies need to work together to understand how all owned assets interact.
Hellingly is an area with consistent flooding which we cannot change without the work of the partnered stakeholders, we can only protect our assets from the excess water. It is clear from our recent work that both surface water and ground water is getting into our system, and we are working to make sure that no longer happens. This will ensure we have the required capacity to ensure foul sewerage removal.
The Hellingly area is a foul only system, the system is not designed to handle the amount of surface/ground water entering and we are working to remove this water from our system. Other infrastructure in the area needs to work in tandem with the foul network in order to stop what is currently happening.
Surface water drainage systems – including gullies, ditches, streams etc
SUDs schemes being followed as designed
Since becoming aware of the ongoing issues in the Station Road area Southern Water has completed the following including high level costs:
Connectivity surveys for the whole area – currently being reviewed (£110k)
Survey for the area has been completed we are waiting for the report to be returned, which will inform our future works.
There has been a number of delays with this survey the longest being land access issues.
Pumped AFDs (£200k)
Installed for houses along Station Road in August.
Asset Protection (£50k)
Manhole sealing to reduce inundation.
Tankers in heavy rainfall to reduce customer impact until longer term solutions are identified.
Electroscan & CCTV surveys of Sewers – currently being reviewed (£30k inclusive of the alternative surveys) Completed along Park Road & Station Road to determine areas of infiltration
Studies into Flow Diversion of future growth (ongoing) – currently being reviewed.
CCTV and survey of alternative sewers will be completed for the Land off New Road development.
Consistent visits with residents. This has given us detailed first-hand information which we had otherwise not received giving us a better understanding of when the issues occur and their severity.
East Sussex Highways comments:
11. ESH confirmed the discharge points for the road drains in Park Road are going into the soakaways and then through the SUD system. There was no connection to foul drains of which they were aware
12. Nick Claxton confirmed (by email) that they are responsible for the attenuation pond and SUDS by Swingate Cross, investigation of maintenance arrangements to be carried out and report back to the Clerk.
13. Hellingly Parish Council thanked Mark for jet blasting the drains on Park Road, this appears to have removed the flooding issue on Park Road, near the junction with New Road, confirmation would be made after the next rainfall.
14. confirmed the discharge points for the road drains in Park Road are going into the soakaways and then through the SUD system.
15. confirmed that they are currently carrying out an investigation to the flooding on New Road and the lower section of Park Road near the new Hellingly Primary Academy and would report back to the Clerk.
LEAD FLOOD AUTHORITY (LFA) Comments
16. Chris Bending advised that Wealden Planning Enforcement will investigate any claims that developments have not been built in accordance with approved plans. This has successfully taken place in recent years, including at a site in this area.
17. Nick Claxton advised that a recent inspection undertaken by Nigel Powers (Lead Flood Authority Officer) at the request of a local resident had identified various deficiencies in the SUDS system approved as part of the Burfield Grange development. He believed that this is the Vistry site at Park Lane West where he had met the resident but the deficiencies noted were observations on the height of the site and the impact that would have on the ability of the drainage system function. Given that there was no evidence that the drainage system does not work there is no action to be taken. The resident also reported concerns regarding outfalls and the condition of ditches towards the west of the site which we are investigating. The developer (Vistry) had agreed to look into those issues, but we have yet to receive a response.
18. LFA advised that given the ownership of the attenuation pond at the junction of New Road and Park Road at Swingate Cross is with ESCC, the setting of the site and surrounding property is equally important as the site itself when considering drainage issues as part of a planning application. As a rule major development will require a Flood Risk Assessment as part of the application and in this the applicant must consider surface water risk to the site from outside and how it will be managed. If surface water risk has not been included, they would insist upon it as it is a fundamental aspect of the assessment.
WEALDEN DISTRICT COUNCIL (WDC) Comments
19. Chris Bending confirmed that the land raised would not be allowed in future without clear evidence that there will be no impact upon adjacent property and that natural surface water runoff from adjacent property will not be impacted. He advised that WDC would always seek to clearly understand the impact of development on flood risk before granting consent, This includes for applications that include land raise. To be clear, WDC do not accept that previously granted developments have failed to take account of this or that said developments have had the impacts claimed, these judgements had been made in the best public interest, using their in-house expert advice, that from the LLFA and others.
Environment Agency (EA) comments:
20. EA advised that they recognise that the Station Road pumping station is in a location that is prone to flooding however the presence of Arlington reservoir control weir means it is extremely unlikely that any part of the river above this structure is ‘tide locked’. They do not have further information on the implications for operation of the pumping station, nor the source of water infiltration in the sewer network.
21. EA confirmed they do not have a responsibility to protect wastewater infrastructure from flooding.
22. EA confirmed that it is the role of water companies to manage the risk of flooding to sewerage infrastructure.
23. EA advised that they are not responsible for maintaining the Cuckmere in such a condition to ensure that the CSO is not tide locked. The design and operation of the CSO is a matter for Southern Water.
24. EA confirmed that some work had been carried out on the lower Bull River below Hellingly within the last 10 years or so and they check the watercourse for blockages that could cause an increase in flood risk to properties.
25. EA advised they don’t have an assessment of river capacity along its entire length but tat they had not seen evidence of a decrease in capacity over time. We understand the river to be a dynamic environment and siltation and erosion will occur wherever conditions allow. Silt removal is expensive (especially if it is contaminated) and temporary. If siltation is an issue then possibly addressing silt sources could be more effective.
26. EA advised they would not expect siltation to have a significant impact on the frequency of flooding in this location. The increased intensity of rainfall events and prolonged wet weather seen in recent years is a more significant factor in causing high river levels and increased frequency of flooding. The ability of sewage systems and surface water systems to discharge to the river is a matter for the relevant authorities. They do however remove any blockages in the main river that would keep river levels abnormally high in areas that could affect people or properties or could impede the operation of drainage systems.
Summary of Action Points agreed at the meeting on Friday 19th January 2024:
Southern Water to:
- confirm the max capacity of the pumping station in Station Road.
- send a copy of their maintenance schedule.
- provide a summary report of the condition survey they carried out.
- provide a ‘misconnections’ report.
- SW & EA to discuss the details of the permit for the Station Road pumping station.
- to resolve any misconnections found with the property owners and advise the Clerk an approx. time frame for the project to be completed.
- investigate the old hospital sewer as a possibility for use and report back to the Clerk.
- advise the Clerk of what if any issues had been found and when the work would done from the connectivity study.
- carry out an investigation for any issues with the drainage of Park Farm and Danecroft Place.
East Sussex Highways to:
- carry out a site inspection on Mill Lane.
- carry out a site inspection of Park Road by the junction of Bulrush Lane.
- send a copy of their maintenance schedule for the SUDS on Park Road to the Clerk.
- Inform the Clerk of the arrangements for the emptying of road gullies in the area
Wealden District Council to:
Graham Kean to provide any historical data he can find on the foul drainage of the former Hellingly Hospital.