OPINION: Thames Flood Diversion – Time For A Rethink?

The River Thames Scheme: piecemeal planning based on unreliable evidence?

OPINION by Miles Macleod
– The following article expresses the views of the author, and does not necessarily reflect the views of PPDRA.

Will the plans for River Thames flood diversion channels be an effective solution for flooding, or a source of bigger future problems downstream and increased flood risk to London?

The Environment Agency’s River Thames Scheme proposes three new flood relief channels alongside the Thames, intended to reduce flooding between Datchet and Chertsey. The final channel, with a capacity of 150 cubic metres per second, would be cut past Shepperton and discharge at Weybridge, opposite the Canoe Club.

‘The River Thames Scheme’ is perhaps a misleading name. Originally called The Lower Thames Flood Risk Management Strategy, it covers the stretch of non-tidal river between Datchet and Teddington. Not the whole River Thames.

Capacity increase funded, impact unknown
Downstream of the three planned relief channels, the River Thames Scheme proposes to widen the Desborough Cut at Weybridge, and to increase flow capacity at Hampton, Molesey and Teddington Locks, to carry extra water onwards towards London.

What would the effects be at Weybridge, and downstream towards London? Would it increase the flood risk?

At present, the Environment Agency can’t say. Why so? Because “the hydraulic model that will be used to assess the impact of the RTS (including downstream of Teddington) is currently being finalised“.

Yet over £300 million funding for the River Thames Scheme has been promised, on the basis of old assumptions and outdated flood risk and flow predictions. Meanwhile – as we will see later in this article – senior figures in the Environment Agency itself are questioning existing thinking on flood protection.

Risk to London
In the 2014 floods, the existing River Thames flow capacity carried 500 cubic metres per second of water over Teddington Weir. The Thames Barrier had to be deployed repeatedly, in sync with normal tidal flows, to help carry the excessive river flow onwards, and hence prevent flooding in the tidal Thames.

The River Thames Scheme proposes to increase the potential flow arriving at Teddington Lock by another 150 cubic metres per second. Will that increase in flow capacity lead to an increase in the flood risk to London? At present, the Environment Agency can’t say.

Some of us are deeply concerned at what seems like a succession of uncoordinated plans – different project schemes, with different political sponsors, looking at different parts of the river – moving the flood risk progressively downstream.

Previous experience
In 2002, a flood diversion channel bypassing Maidenhead, Windsor and Eton was opened. It discharges just upstream of Datchet. Called the Jubilee River, and costing £110 million, with a capacity of around 170 cubic metres per second, it has helped divert floods from Maidenhead, Windsor, Eton and Cookham.

In the years since the Jubilee River was opened, flooding has increased from Datchet downstream. That, according to the Environment Agency, is a coincidence. They say that the Jubilee River “operates so that flood levels downstream are not adversely affected”.

Local concerns
In 2009 the Environment Agency put forward the Lower Thames Flood Risk Management Strategy, setting out plans to address the flood risk downstream of the Jubilee River. That raised hopes for some people, and worried others.

In Elmbridge, people were concerned by the potential downstream effects of a flood relief channel discharging at Weybridge, and also the proposals for cutting into a significant amenity, the popular stretch of the Thames Path and National Cycle Route which runs alongside the Desborough Cut. The Environment Agency called this an ‘access track’. They proposed to widen this side of the Desborough Cut by 3-4 metres, and move the ‘access track’ closer to the road (Walton Lane) – but not to widen the two bridges across the Cut, which are existing bottlenecks restricting flow.

Elmbridge objections
The author of this article, Miles Macleod, was at that time an Elmbridge Borough Councillor for Weybridge North. That is where the planned third flood relief channel would discharge, bringing 150 cubic metres a second of additional water flow capacity. He alerted Elmbridge Borough Council to the implications for the Borough of the plans. Others councillors agreed that this was a serious issue for the Borough.

Elmbridge Borough Council studied the plans, and was concerned. It concluded in January 2010 that it could not support the plans for widening the Desborough Cut – plans which would need the Council’s consent.

Elmbridge Borough Council also said that the projections for flood risk and flows needed credible independent external verification, and fluvial and tidal flood strategies should be coordinated.

PR campaign
The Environment Agency found that in the financial climate of the time it could not secure funding for its Lower Thames Flood Risk Management Strategy plans. So it spent five years actively promoting the plans and the projected benefits, using its old flow calculations as evidence. It renamed the strategy as The River Thames Scheme – a name suggesting something more far-reaching than the lower Thames between Datchet and Teddington – but still could not raise enough funding.

Then the February 2014 floods came upon us, with particularly severe effects on residential areas between Datchet and Chertsey (downstream of the Jubilee River). The result was political pressure to fund the proposed Lower Thames flood relief channels between Datchet and Weybridge (and the wider Desborough Cut). At the time, a general election was not far away.

Lo, the remaining funding for the River Thames Scheme was secured. And it was secured despite new evidence about river flows and flood levels – experienced in the 2014 floods and more recently – which raised serious questions about existing flood risk and flow calculations and modelling, including those underpinning the River Thames Scheme.

Misguided approach
The relief channels should help moderate short term extreme peaks of flow, but if there are extended periods of very high flow they have the potential to increase the total volume of water flow arriving at Weybridge by some 30%.

The Environment Agency reassuringly says that the differences in projected flood risks are expected to be small in the revised calculations, drawing on recent evidence added to the accumulated evidence of the past 130 years. But the fact remains that the scheme begs questions which at present don’t have good answers.

The answers may continue to change: with a changing climate and more extreme events, we cannot rely so much on probabilities calculated from the frequency of past flood events. Flood risk models must build in higher probabilities of known maximum flows and levels being exceeded.

Complete rethink
There is a basic concern.

Flood defences need a complete rethink. Who says so? The Environment Agency.

Rarely has a truer word been spoken.

The Agency’s deputy chief executive, David Rooke, has said the UK’s climate is entering an era of unknown extremes, and that a complete rethink of flood protection and resilience across the country is needed.

The £300 million River Thames Scheme plans are based on calculations of risks and flows which recent evidence has already shown to be unreliable. They reflect a limited view of flood protection, and potentially increase flood risk to London from an extreme event, by significantly increasing flow capacity into the tidal Thames.

New approach needed
Successive extreme floods in various parts of Britain have led many people to the conclusion that current flood strategies are flawed, too narrowly focused and trying to tackle flood problems in the wrong way.

Piecemeal plans which move flood risk downstream are unacceptable.

A new approach is essential. The Thames needs a better thought out whole catchment plan, to help reduce the size of flood peaks along the length of the river – even in extended periods of exceptional rainfall.

A whole catchment plan might start with initiatives to slow down inflows along the length of the river, rather than trying to increase capacity in first one problematic stretch of the river, then another downstream.

Yet the River Thames Scheme appears to be going forward with great determination, to deliver what history may judge to be a very expensive mistake: an outdated, narrow and ultimately damaging project.

Time for that complete rethink? It is not too late!

Responses are welcome. Interested in contributing an opinion piece? Find out more…

Weybridge Parking Review – PPDRA Response

On 17 January 2016, PPDRA sent the following to the Surrey Highways Parking Strategy & Implementation Team. It draws on extensive local discussion by our committee, input from residents at meetings and via a survey, and discussions with local groups.

PPDRA submission to SCC Weybridge Parking Review

Portmore Park & District Residents Association (PPDRA) recognises that Weybridge needs adequate parking for residents, shoppers, visitors and workers, if our town is to thrive. We also know that this is a difficult balance to achieve.

The PPDRA committee broadly welcomes the principle of reducing parking restrictions to help increase capacity, where that is possible and desirable, so long as

a good balance of priorities is achieved (especially the balance between parking for residents, shoppers and workers)
safety is kept as a prime consideration.

We welcome the principle of consulting residents of individual roads about the specific needs of their road, especially where residents are being displaced from limited parking spaces in their own road.

PPDRA believes there is a very strong need for more public off-street parking, priced more affordably, and convenient for Weybridge town centre. This is a view which has been widely expressed by local residents in our community meetings and surveys. Cheap or free short stay parking in particular could help the town centre thrive. Affordable long stay off-street parking is also much needed, within reasonable walking distance.

We recognise that allowing on-street parking can have positive outcomes beyond a simple increase in parking capacity, especially in potential rat runs. Traffic speeds in our local residential roads are a major issue. Parked cars can be a positive natural form of traffic calming: for example, Portmore Park Road and Thames Street are unclassified residential roads which without parked cars might become high speed rat runs for through traffic.

Thames Street and Portmore Park Road include schools and a church, which have different parking needs and impacts on the community, meriting additional thought about how best to enable the required mainly short stay parking nearby. PPDRA has met with St George’s Junior School 3 times a year since 2002, liaising on issues including how best to manage school run drop off and pick up parking. We have also discussed parking issues with representatives of Christ The Prince of Peace church and other local groups. We note that Thames Street has recently faced issues of excessive obstruction caused by inconsiderate parking at the upper end between the junction with Grotto Road and Monument Green.

The most serious parking issues locally arise close to Weybridge High Street. The Portmore Park and District area of north Weybridge has a fair density of mainly Victorian homes with no off-street parking. The lack of private off-street parking is a particular issue in roads adjacent to the High Street, where shoppers and town centre workers look to park their cars. The result has been that residents of these roads, returning from a school run or shopping journey, risk finding nowhere to park within walking distance of their home. Hence many living in these roads favour residents’ parking schemes.

PPDRA has long supported the principle that Surrey County Council should consult residents of individual roads about specific residents’ parking schemes for their road.

The PPDRA committee also recognises the need to permit short term shopper and visitor parking in such roads, with a good level of churn, so long as it allows for the needed level of daytime residents’ parking. It is not good to see ‘residents only’ parking zones with few parked cars in daytime, when shoppers can find nowhere to park and when local shops are in need of footfall.

Further from the High Street, many homes in Portmore Park & District have private off-street parking. For roads where there is no issue of residents being displaced from essential on-street parking, as a general principle the majority of the PPDRA committee would favour only minimal restrictions, simply where safety issues demand double yellow lines on dangerous corners. However, we appreciate that there is concern among residents in some roads (particularly Wey Road and Round Oak Road) about potential displacement of parking into their roads if CPZs are introduced elsewhere, and we feel this issue needs careful consideration by Surrey.

We are aware of specific issues in Radnor and Glencoe Roads where there is a very high density of houses and almost no off-street parking, and Church Walk which has very limited parking. Some residents of these and other roads rely on their parking being able to overflow into on-street parking in Portmore Park Road.

PPDRA would be happy to contribute further on any way possible to help support Surrey County Council (and Elmbridge Borough Council) in finding ways to achieve adequate parking for Weybridge residents, shoppers, visitors and workers.

Weybridge parking review – hope on hold?

People hoping for early action on chronic parking issues which afflict some roads in Weybridge may be disappointed at new plans from Surrey. The idea is sound – a strategic parking review looking at needs as well as restrictions, seeking to free up spaces – but the timing and interim arrangements have left some residents feeling badly let down.

Despite previous talk of Weybridge getting an early review, we have been moved down the queue, behind Cobham. That may mean waiting until 2017 for changes.

Frozen out for now?
Until after the review, Surrey propose not to act on local parking issues unless there is an ‘irrefutable serious road safety implication’. The current system for making numerous changes yearly – to deal with specific local problems soon after they arise – will cease. This would mean proposals to deal with pressing parking issues in Dorchester Road and near the top of Thames Street being left in limbo.

So where does that leave Dorchester Road residents who were given hope of early action when they took a petition to Surrey (see PETITION RESPONSE DORCHESTER ROAD. WEYBRIDGE FOR INFORMATION)? They would love to know.

Consultation
More positively, the SCC ELMBRIDGE PARKING STRATEGY EXECUTIVE FUNCTION REPORT — presented to the Surrey County Council Local Committee on 23 February 2015 — proposes a high level of consultation, using an external consultant to engage with local groups. PPDRA is determined to ensure that local Weybridge views get a good hearing.

There is a strong feeling locally that there is an overall shortage of parking in Weybridge town centre, and better collaboration is needed between Surrey County Council (responsible for on-street parking), Elmbridge Borough Council (responsible for some off-street parking) and businesses (also responsible for some off-street parking).

Surrey County Council Proposals

So what has Surrey proposed? Well, the SCC Elmbridge Parking Strategy Executive Function report prepared by Rikki Hill has a promising start:

Reasons for Recommendations. In the past, reviews of parking have tended to be reactive in nature and concentrated on where parking was not desirable and so should be controlled or restricted. A more strategic approach would allow us to also consider where parking is needed and how those parking needs may be met.

But the analysis suggests a longer than anticipated wait for action on local issues:

2.8 Adopting this new more holistic approach to reviewing parking will mean that it will not be possible to review the whole of Elmbridge at the same time. We would therefore need to review each area within the borough on a rolling programme and it would make sense to start with the Cobham area (including Stoke D’Abernon and Oxshott) as the Cobham Chamber of Commerce have already collected a considerable amount of information about the needs of local businesses and the amount of existing private off street parking spaces.

2.9 Taking into account the number of possible problems that have been brought to our attention in the last couple of years, we should then look at Weybridge, followed by the Moleseys and the Dittons, then Esher, Claygate and Hinchley Wood. We should finish with Walton & Hersham, as this is where there has most recently been a comprehensive review.

2.10 The aim would be to complete the reviews in all the areas within the next three financial years after which we would review our strategy and consider whether to start the process again or adopt a new approach.

2.11 As there may still be parking issues that arise outside of the above programme, where there is an irrefutable serious road safety implication, we would want to continue with a smaller version of the current review system to deal with these.

The parking issue in Dorchester Road probably doesn’t have “an irrefutable serious road safety implication”. A case might be made for safety improvements at the top of Thames Street, but our previous experience of arguing for restrictions on safety grounds — at the end of Grotto Road — was that Surrey County Council really wanted evidence of someone being seriously injured (“anyone can say a road is dangerous, but we need to see evidence”).

The root of the issue north of Weybridge High Street is that parking by non-residents has been squeezed out of adjacent roads by restrictions (including residents-only parking). So Dorchester Road and the top of Thames Street have become the nearest accessible places for town centre workers looking for spaces, leaving some residents with nowhere to park. And now Weybridge has a new supermarket with no on-site staff parking spaces.