Contents

  1. Get help during a flood
  2. Report flooding
  3. Find out if you’re at risk of flooding
  4. How we’re managing local flood risk
  5. Strategic Flood Risk Assessment
  6. Sustainable drainage in planning applications
  7. Section 19 flood investigations
  8. Raynes Park Flood Alleviation Study

Updating Merton’s Local Flood Risk Management Strategy and Surface Water Management Plan

We’re starting an update of Merton’s Local Flood Risk Management Strategy and Surface Water Management Plan. Once our consultants have gathered the most up-to-date evidence, later in 2024 we would like to hear your views on how flood risk is managed in Merton and on the emerging strategies. We will update this web page and please keep an eye out for communication as your feedback can help shape how flood risk is managed across the borough.

Local Flood Risk Management Strategy 2015

We have a duty to co-ordinate flood risk management within the borough and to ensure that certain flood risks are identified and managed appropriately.

Merton’s Local Flood Risk Management Strategy sets out our plan for managing local flood risk across the borough until 2020.

Following a public consultation, Merton’s Local Flood Risk Management Strategy was formally adopted on 28 May 2015.

Investigating significant flooding events

We have a duty to investigate and publish the findings of any significant flood events within Merton. Significant flood incidents are defined in our Local Flood Risk Management Strategy.

All reported flooding incidents that meet the criteria set out in our local strategy, will require a formal flood investigation (under section 19 of the Flood & Water Management Act) and will be recorded in our Flood Incident Database. This allows us to improve our understanding of flood risk and flooding mechanisms across Merton. More information can be found here: Flood risk investigations.

Managing ordinary watercourse activities

We  make sure that watercourses are kept clear of obstructions to prevent flooding. This involves giving consent for work to be carried out and we will take enforcement action if work is unacceptable.  In Merton the following rivers are defined as Main Rivers and fall under the responsibility of the Environment Agency:

  • River Wandle
  • Beverley Brook
  • Pyl Brook (inc. East Branch)
  • River Graveney
  • Bunce’s Ditch
  • The Pickle
  • Wandle Park Ditch
  • Figges Marsh Ditch

All other watercourses are classed as Ordinary Watercourses and fall under the responsibility of Merton LLFA.

If you own land above or with a watercourse running through it, you are a ‘riparian owner’ and have responsibilities. You must make sure that the watercourse is maintained and all obstructions (natural or otherwise) are cleared so the normal flow of water is not blocked..

If you want to do any any works to an ordinary watercourse you will need our permission before starting work. Please contact us via email: enquiriesfuturemerton@merton.gov.uk

Flood risk management plans and maps

We produced our first Preliminary Flood Risk Assessment in 2011