Proposed Gurnell development will increase flood risk and encroach on protected land

The Brent River & Canal Society (BRCS) has expressed serious concern about Ealing Council’s proposal to build 295 flats next to Gurnell Leisure Centre, for two main reasons:

  1. The development would increase flood risk along the River Brent. 
  2. The land earmarked for development is protected by national, London-wide and Ealing Council’s own environmental and planning policies.

The proposed development would see four blocks built to the East of the proposed new leisure centre, West of Peal Gardens and North of Ruislip Road East. 

Plan from Ealing Council’s planning application.

Increased Flood Risk

The proposed residential development would increase the risk of properties along the River Brent being flooded. 

The Flood Risk Assessment submitted as part of Ealing Council’s planning application admits that the development would mean a reduction in floodplain storage. The council’s proposed compensation plan consists of a series of warning systems and an underground car park which “has been intentionally designed to flood“. In the event of a flood, the cars would be evacuated and the car park would convert to being a flood water storage tank, with the water being pumped out once the risk of flooding had receded. 

As the minutes of the council’s meeting with the Environment Agency note: 

“The residential development will reduce flood plain volume. This is largely compensated through allowing the leisure centre car park to flood.” 

These proposals are disappointingly unrealistic and ill-thought-out. The plan to use an underground car park as flood storage is a very high-risk strategy. It places a huge reliance on technology. It also rests on the assumption that there will be adequate advance warning of floods. However, the severe downpour in July 2021 took London by surprise. A sudden flood could potentially see a car park full of cars submerged or, alternatively, sealed off against flood water, diverting it to homes and businesses nearby. 

The council’s Flood Risk Assessment also claims that there is risk to neighbouring properties on Peal Gardens and that a “marginal increase of up to 30mm” could be “contained within back gardens”. It is highly unlikely that this will be of much comfort to the residents. An increase of 30mm in the floodwater in a back garden could be the difference between a home flooding or staying dry. 

Ealing Council may deem these risks acceptable but the calculations on which the risk assessment is based could change radically over the coming years. Decisions made today need to work with the environment of tomorrow. The frequency and severity of flooding is expected to increase over the next decade. We have no idea how severe the flood risk will get but it is significant that the insurance industry is not prepared to guarantee its FloodRe scheme (which subsidises the premiums of high-risk properties) beyond 2039. That is well within the lifetime of the mortgages that will be taken out to buy the Gurnell properties and many of those nearby. 

The Brent River Park is crucial to Ealing’s flood defences

The BRCS is opposed to any reduction in floodplain volume and, therefore, to any increase in hard standing in the Brent River Park. The Park is a critical component of Ealing’s flood defences. For example, the green spaces by the river between Hanger Lane and the Wharncliffe Viaduct regularly flood after heavy rain. They absorb and retain the surge of water that would otherwise swell the river and cause serious problems for homes and businesses. The building of 295 apartments would reduce the park’s flood storage capacity and therefore increase the likelihood of properties being flooded in Perivale, Pitshanger, Greenford and Hanwell. 

Most of the Gurnell area is already classed as ‘functional floodplain’ (an area intended to flood) by the Environment Agency. The site flooded as recently as 2022, as the picture below shows. 

Flooding at Gurnell in 2022. (Photo by Save Gurnell)

The flood risk map below shows Environment Agency’s designations for the Gurnell site. Functional floodplain is shown in red and much of the rest of the site designated as ‘high risk’, shown in purple. The map also shows risk from surface water flooding (coloured orange), which occurs when heavy rainfall overwhelms the roadside drainage system. This combination of river and surface flooding compounds the risk to neighbouring properties. 

Map by West London Strategic Flood Risk Assessment

In 1977, there was severe flooding at Coston’s Lane and the resulting outcry caused Ealing’s flood defences (a combination of barriers and water-absorbing parkland) to be developed in the 1980s. But this system is now under strain. As global warming is increasing the volume and frequency of rainfall, sudden heavy rainstorms are becoming more common. 

Ealing Council’s own Flood Risk Management Strategy acknowledges the importance of the Brent River Park as ‘the borough’s functional floodplain’ in preventing flooding and says that the council:

“Will look at the potential of creating other parks, or areas of restricted development, to allow space for water and prevent increased flood risk due to poorly sited developments.”

Putting buildings and more hard standing on the park is the opposite of what the council’s own policy suggests. The Brent River Park is doing its job as a flood defence and to reduce its floodplain capacity would be a damaging step. 

Coston’s Lane by Greenford Bridge, August 1977, before the flood protections were put in place (Photo via Ealing Council.)

The proposed apartment blocks would be built on protected land

By building on protected land, the proposed development runs counter to national, London-wide and local planning policy. The entire area earmarked for development is on development would be built on protected land. As the map below shows, the entire area earmarked for development is on Metropolitan Open Land (MOL – shaded green) and the two northernmost residential blocks would also be on Public Open Space (POS – shaded with diagonal lines).  

Section of Ealing Council’s Local Plan map

The site is currently designated as Metropolitan Open Land (MOL). MOL is urban Green Belt. This prevents the site being used for residential development. 

In his response to Ealing Council’s latest Local Plan, the Mayor of London made the following comments on the proposed development of Gurnell:    

“The proposed use is for residential development which the Mayor considers is inappropriate development in MOL.” 

Two of the residential blocks would be built on land that it designated as Public Open Space. This, too, is protected by council policies. In April 2022, Ealing Council rightly rejected a planning application to build on Public Open Space in Acton (Ref 220577OUT). 

The first reason given was:

“The proposed development by reason of its siting on designated public open space, would not be acceptable in principle, as it would be contrary to Chapters 8 and 15 of the National Planning Policy Framework (2021), policy G1 and G4 of the London Plan (2021), policy 1.1 and 5.5 of Ealing’s Development Strategy (2012) and policy 2.18 of Ealing Development Management Documents (2013).”

If building on Public Open Space is not acceptable for the reasons quoted here, then surely it is not acceptable at Gurnell. 

The National Planning Policy Framework states that Public Open Space should not be built on unless it is surplus to requirements, is being replaced by equivalent or better provision or is to be used for alternative sports and recreation provision, the benefits of which clearly outweigh the loss of the current or former use. None of these conditions apply, so the proposed development clearly contravenes national government policy.

Brent River & Canal Society (BRCS) Chair Phil Belman commented:

“We stand alongside residents wanting to see Gurnell Leisure Centre brought back into use. The pool is sorely missed and it is important for health and wellbeing to re-open what was once a well-used facility. However, we must be realistic on this latest proposal. Building houses and flats on the Brent floodplain in the Brent River Park is unwise. These new homes will carry a significant flood risk as soon as they are built. Furthermore, they will increase the risk to properties and homes nearby and further along the River Brent. We know that climate change is already producing more flash floods. Ealing Council should be trying to reduce the amount of hard-standing close to our river, not increasing it.”

Brent River & Canal Society (BRCS) Trustee Steven Toft added”

“The housing development is proposed on Metropolitan Open Land and Public Open Space both of which are protected by national, London wide and local policies. This proposal also runs counter to Ealing Council’s own policies. The council rightly refused ‘in principle’ a development on Public Open Space in Acton in 2022. Surely the same principle applies at Gurnell.”

The Brent River Park charity is urging Ealing residents to respond to the planning consultation and to emphasise the following points:

  • The proposed development will reduce the site’s flood storage capacity and increase the flood risk to nearby properties and those further along the River Brent.
  • The flood mitigation proposals are inadequate and unworkable.
  • In the face of massively increasing rainfall, Ealing Council should be improving flood resilience by reducing hard-standing next to the river, not increasing it.
  • The proposal runs counter to Ealing Council’s own Flood Risk Management Strategy.
  • The proposal runs counter to national, London-wide and local planning policy which protects Metropolitan Open Land (MOL) from inappropriate development.
  • The development should not reduce or encroach on Public Open Space (POS).

Follow this link for the consultation documents and this link to leave comments. Reference: 241706OUTR3

The closing date for comments is 18 June 2024. 

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Follow this link for the full text of our objection.