Agenda item

To receive an update on flooding and consider the effectiveness of flood mitigation measures including SuDS. Progress on the gully clearance programme will also be reported.

Contributors:

Cllr Gareth Williams, Cabinet Member for Climate Change & Environment

Cllr Jilly Jordan, Deputy Cabinet Member for Climate Change and Environment

Cllr Steve Broadbent, Cabinet Member for Transport

Ian Thompson, Corporate Director for Planning, Growth & Sustainability

Richard Barker, Corporate Director for Communities

Steve Bambrick, Service Director for Planning & Environment

Karen Fisher, Strategic Flood Management Team Leader

Vikki Keeble, Sustainable Drainage Team Leader

The Chairman introduced the Deputy Cabinet Member for Environment, Councillor J Jordan, to introduce the report and outline the presentation that would be provided by officers. In the presentation, the following points were made:-

·       In Buckinghamshire, 10.7% of land lies in Flood Zone 2 and 3 (equivalent to over 8,000 properties) and 8.4% of land lies in areas at high or medium risk of surface water flooding (equivalent to over 4,000 properties). The landscape was likely to change in response to climate change.

·       Buckinghamshire Council acted as the Lead Local Flood Authority (LLFA) which required partnership working with the Environment Agency (EA) and water companies predominantly. The statutory role was outlined by officers.

·       The roles and responsibilities for each authority were highlighted for flood risk management and flood incident management.

·       The Strategic Flood Management team had a series of projects funded by central Government, regional committees, and the Council. Defra currently funded Project Groundwater 2021- 2027 which was focused on groundwater resilience in the Chilterns. The team was also responding to drainage aspects of planning applications of more than 10 units and linked with other council work such as Tree Planting and the Local Nature Recovery Strategy.

·       Sustainable drainage systems (SuDS) were designed to manage stormwater locally and emulate natural drainage. They also enhanced the local amenity and biodiversity. Planning applications were required to provide a surface water drainage strategy; examples included the use of permeable paving and rain gardens.

·       The council’s approach to flood risk management was consistent with the EA’s national strategy by creating climate resilience. The River Leck Natural Flood Management Scheme, which used leaky dams, was an example of this work. The Council also wanted to educate residents on flood risk and resilience.

·       The Local Flood Risk Management Strategy would be revised in 2023.

The Cabinet Member for Transport introduced the gully clearance report which updated on the progress of maintenance. The Council had committed to clean every drain and gully last year, costing £2m revenue, with another £2m capital investment of repairs. This exercise was being repeated for every gully this year. Last year’s work had established a baseline of silt levels for each gully which was being checked against this year during the second year of cleaning. There were 7-8 gully teams carrying this out per day, and the super suckers were proving to be important.

In response to Member questions, the following points were noted:-

·       It was acknowledged that the responsibilities for flooding were complex for all agencies which was confusing for Members and residents. The Council hosted a list of responsibilities on its website and signposted queries accordingly. The EA did have strategic oversight of flooding at a national scale which was then acted upon locally by partners which was stipulated in the Flood and Water Management Act.

·       It could be challenging to encourage developers to deliver ‘greener’ SuDS that incorporated into the landscape. Recent changes to the Local Planning Policy guidance, which emphasised the need for SuDS to take into account water quantity, water quality, biodiversity and amenity, would help to hold developers to account.

·       When speaking with residents regarding concerns of flooding and new developments, Members were advised developers had to manage their flows so that they are stored and slowly released at a controlled rate that is agreed with the LLFA and the planning authority.

·       There was regular liaison between Strategic Flood Management and Transport for Bucks (TfB) regarding road flooding and gullies with each having its own responsibilities.

·       The team followed Government climate change guidance and updated its work as the guidance changed. The latest guidance on climate change allowances could be found on the Gov.uk website: Flood risk assessments: climate change allowances. This guidance applied to both flood management projects and planning applications. For example, a developer was required to demonstrate that surface water runoff from the impermeable areas on a development can be safely contained on site for storm events up to the 1% Annual Exceedance Probability (meaning a storm event that has a 1% chance of occurring in any given year). This would include a 40% uplift on peak rainfall to account for climate change. 

·       Project Groundwater sought to address groundwater flooding which was a lesser-known and hidden issue in flooding, and its impact could be devastating and long-lasting. The project was looking to create mapping information and a warning system using bore holes.

·       Following the Section 19 Flood Report in Buckingham, an update on the recommendation regarding combined sewers work with the EA and Anglian Water would be requested. The response would be circulated separately once available.

Action: K Fisher / V Keeble

·       The purpose of the national and local policy was to steer development to the areas of lowest flood risk as set out by the Sequential Test and sequential approach. Statutory consultees, such as the LLFA and the EA, supported the planning authority in steering development to the lowest risk. There was a national record of planning applications approved contrary to the EA advice. The planning authority was not required to record the same information for decisions taken against the advice of the LLFA.

The Chairman thanked Members and officers for the discussion and requested that any further questions be referred to the Chairman and the Senior Scrutiny Officer outside the meeting.