Answers to concerns

Some people have had concerns about the Oxford Flood Alleviation Scheme – the Environment Agency have recently made this response which we thought people might find of interest. (To avoid making it even longer we have not included the questions but the answers should make it clear enough what the questions are.)

Design of the scheme 

The scheme has been designed to be as natural as possible and respects and works with the existing natural floodplain. It is not a concrete channel. It is not an ‘on/off’ channel but a passive design which allows the natural floodplain to carry more water when needed. Most of the excavated area will be planted with vegetation and provide valuable new habitat for the area. It is designed to increase the capacity of the floodplain to carry more water.

The Oxford Flood Alleviation Scheme will not increase flood risk to properties downstream of Oxford. The scheme does not hold back water (like a flood storage scheme) nor does it speed up water (like a deep narrow channel could do). We conduct detailed modelling, which is always independently verified, and this shows the scheme will not increase flood risk to properties downstream of Oxford. In addition, the Vale of White Horse District Council also commissioned a completely independent review of downstream impact. This was published in December 2017 and confirmed that the scheme will not increase flood risk to downstream properties.

Willow Walk 

We will be removing the existing culverts and their metal railings, shown below and will install a new bridge in their place.

The existing Willow Walk track is already raised above Hinksey Meadow. The new bridge will continue from this track, just raised slightly higher, and will span 19 metres. The height of the deck of the bridge will be approximately 1.5 metres above the existing footpath. The bridge needs to be this size to allow flood water to pass underneath it.

We recognise the importance of Willow Walk as an historic route and a key east-west link for pedestrians and cyclists into Oxford City. Access will be needed for occasional maintenance vehicles. We have confirmed previously that there are no plans to turn Willow Walk into a road.

 Green Belt

If the scheme is approved we believe it will help to safeguard the Green Belt in this area as it will need to remain as a functioning flood alleviation scheme for at least the next 100 years. This will help to maintain and preserve the openness of this part of the Green Belt. The natural design for the scheme includes the creation of over 20 hectares of new habitat. The scheme aims to bring a long term green legacy to the area.

 Maintenance

The scheme will have a long term maintenance plan for the lifetime of the scheme, 100 years. This includes managing the vegetation in the area by grazing. The ‘second stage’ wider part of the channel has been designed to be grazed by cattle to create floodplain grazing marsh. Temporary fencing and removable barriers will allow the second stage channel area to be grazed. We will also create many wetland features within the second stage channel to maximise available habitat for wetland and aquatic species. The backwaters, scrapes and ponds will have a variety of depths, dimensions and gradients, to encourage diversity of wetland wildlife.

Existing streams

The new flood alleviation scheme does not divert water away from Seacourt, Bulstake and Hinksey Streams. The scheme lowers the existing natural floodplain so that in the event of high flows it can carry more water. In the Hinksey Meadow area, the existing Seacourt Stream will act as the first stage channel.

Managing excavated material

A Materials Management Plan has been submitted as part of the planning application. This plan explains the options we considered for both the management of the materials excavated as well as the options for transporting the material from the site. There are no plans to use North Hinksey Village to divert traffic or transport materials. We will construct a haul road specifically for construction traffic within the scheme area to reduce the need for lorries to drive on local roads to access different areas of the site. However, we will be removing a large amount of material which will need to remove from site. Lorries will leave the site via a new compound and access road at South Hinksey and join the A34. This will be our main compound and access point onto the road network.

The majority of the material being excavated will be alluvium, a silty clay. We will reuse this material in the proposed flood embankments where possible. Excavated gravel will be re-used in the scheme for environmental improvements and on the channel of the new river bed.

Most of the material leaving the site will be transported to old quarries and will be used to restore these sites. Once planning permission for the scheme has been granted we will be able to confirm which sites have the capacity and necessary permissions to receive the material.

Tree planting

To mitigate for the estimated 2,000 trees that will need to be felled during construction, we will be planting 4,325 trees. Approximately 15,000 smaller tree species, such as hawthorn, hazel and elder, will also be planted, along with many more native shrubs such as dogwood, goat willow, dog rose and wild privet. The tree-planting proposals result in more woodland within the scheme area after completion, than there currently is at present. These woodland areas will be managed for wildlife and include glades that are sown with wildflowers to encourage butterflies and other insects, as well as birds and foraging bats.

The replacement woodland trees will be saplings and it will be many years before they have the same ecological value as those being felled, so throughout the design process, our contractors, engineers and ecologists have worked together to minimise tree loss wherever possible. Once a contractor has been appointed we will work with them to further minimise losses of mature trees wherever possible. The contractor will also protect all retained trees and hedgerows within the scheme boundary by erecting stout fencing before materials or machinery are brought on site and before any work starts.

The Environment Agency is committed to the scheme bringing additional environmental benefits beyond reduced flood risk, and this includes our consideration for the trees and wildlife across the scheme area.

Dredging

Dredging the River Thames would not significantly reduce flood risk to Oxford. Even if we dredge all the channels that currently exist in Oxford, it would not reduce flooding from a major flood. In many cases, dredging isn’t the best long-term solution because rivers can quickly silt-up again. It can even increase flood risk downstream, alter the ecosystem, be environmentally damaging, costly and disruptive. Studies have indicated the River Thames would require frequent re-dredging as the natural tendency of all rivers after dredging is to deposit silt and return to their more natural dimensions. And it would not be a cheap option to dredge the River Thames.

 

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Vicki Arroyo: “Let’s prepare for our new climate”

Vicki Arroyo is the Executive Director of the Georgetown Climate Center at Georgetown Law, where she also serves as the Assistant Dean of Centers and Institutes and a Professor from Practice. See here for more about her: https://www.georgetownclimate.org/about-us/staff.html

In the video below she talks about preparing for and adapting to climate change. She ends with:

“The larger point I’m trying to make is this. It’s up to us to look at our homes and our communities, our vulnerabilities and our exposures to risk, and to find ways to not just survive, but to thrive, and it’s up to us to plan and to prepare and to call on our government leaders and require them to do the same, even while they address the underlying causes of climate change. There are no quick fixes. There are no one-size-fits-all solutions. We’re all learning by doing. But the operative word is doing.”

As a flood plain city Oxford is very vulnerable: seven main rivers meet at Oxford, with a combined upstream catchment of about 2,500 km2. For over 10 years our Alliance has been talking to, calling on, and working with, the authorities responsible – from the Directors of the Environment Agency to local government and other bodies –  to make Oxford better prepared for what climate change will bring. A good deal has already been done but more is needed; the Oxford Flood Alleviation Scheme will enable Oxford to continue to thrive. Without it we may be, almost literally, sunk.

Accompanying editorial

Good to see this positive and supportive editorial.

Trees

The Environment Agency has looked again at the question of trees in the Oxford Flood Alleviation Scheme (OFAS) – this is from their recent newsletter:

‘We have listened to local concerns about the impact the scheme will have on trees and recently conducted some additional tree surveys. Although trees will unfortunately have to be felled during the construction stage, we can confirm that our tree-planting proposals will ensure there will be more woodland within the scheme area after completion, than there currently is at present. 

By surveying individual trees by eye, we estimate that 2,000 trees will need to be felled. To mitigate for this we will be planting around 4,325 trees. In addition, 15,000 smaller trees, such as hawthorn, hazel and elder, will also be planted, along with many more native shrubs such as dogwood, goat willow, dog rose and wild privet. Throughout the design process, our contractors, engineers and ecologists have worked together to minimise tree loss wherever possible. Once a contractor has been appointed we will work with them to further minimise losses of trees wherever possible. 

Our aim is for the scheme to bring a true green legacy to the area. We are currently exploring options for the long term maintenance of the scheme to ensure it is not only maintained as a flood scheme, but continues to provide lasting environmental improvements well into the future.’

Seacourt P&R extension – work halted

Make of this what you will – what is going on?….

https://www.oxfordmail.co.uk/news/17269391.park-and-ride-expansion-work-stopped-and-its-unclear-when-it-will-restart

“In papers, the council said it has stopped the work because it wants to get it ‘right’.”

Rather suggests they were getting it wrong (we’d agree with that).

From the agenda pack of the meeting of Oxford City Council’s Finance Panel of the Scrutiny Committee on Thursday 6 December:

[p. 17] “7. Direct Services Client – £0.494 million adverse variance arising from a decline in car parking income. It was originally envisaged that visitor numbers travelling into the city by car would significantly increase with the opening of Westgate and City Council car parks would benefit, however any increased business together with existing business appears to have gone to the Westgate car park. Worcester Street and Oxpens car park are both seeing a decline in usage which is having a significant impact on income.” 

[p. 18-19] “10. A thorough review has been made of the Capital Programme as at the end of September 2018 and this has led to a significant amount of slippage into future years. The projected outturn on the Capital Programme is currently a favourable variance of £15.945 million against the latest budget of £109.665 million. The main variances are:….. 

  • Extension of Seacourt Park and Ride – £3.217 million is to be slipped, this is the remaining balance of funding. It is important to get the detail of this project right and it is unlikely that works will commence in this financial year.”

 

 

Future UK climate

From the new (26 November 2018) Met Office report on the challenge of climate change in the UK:

‘The projections will be factored into the UK’s flood adaptation planning and the Environment Agency’s advice to flood and coastal erosion risk management authorities.

Since 2010 government has invested a record £2.6 billion in flood defences, and we are on track to protect 300,000 more homes from flooding by 2021.

Chair of the Environment Agency, Emma Howard Boyd, said: “The UKCP18 projections are further evidence that we will see more extreme weather in the future – we need to prepare and adapt now, climate change impacts are already being felt with the record books being re-written.

“It is not too late to act. Working together – governments, business, and communities – we can mitigate the impacts of climate change and adapt to a different future.

“The Environment Agency cannot wall up the country, but will be at the forefront – protecting communities, building resilience, and responding to incidents.” ‘

The UK’s most comprehensive picture yet of how the climate could change over the next century has been launched today by Environment Secretary Michael Gove.