OFA Update / OFAS & Flood Exercise

This update has recently been sent to those on our mailing list.

Dear OFA contact,

We last sent out an update in Oct 2019, just after the news about the problems with the A423 bridge (southern bypass) and likely delays to the Oxford Flood Alleviation Scheme (OFAS). OFA is still active and has been participating in meetings of the Sponsoring Group for the OFAS scheme and has also held separate meetings with the Environment Agency team about water course maintenance since our last update.

Despite the A423 issues, and the challenges presented by coronavirus, the OFAS scheme continues to progress. The EA and the County Council have agreed a collaborative approach to replacing the A423 bridge and constructing the OFAS scheme. This should save on costs for OFAS, and reduce the level of maintenance required in future.

The EA withdrew the original planning application earlier in the year and is currently revising this to incorporate the new A423 arrangements, and to update the documents on some other aspects of the scheme. Once these are resubmitted to the planning authority the public will have a fresh opportunity to comment on the plans. The EA is continuing to meet with objectors to the scheme with a view to trying to address outstanding areas of public concern.

Because OFAS is now expected to be delivered two years later than originally expected it is important that effective flood response procedures are in place in case a major flood event happens in the next few years. The EA, Fire Brigade and the local Council officials will be holding a practice response on 20 August to test aspects of current procedures. Because of coronavirus these will not involve the pubic.

The text of a recent update from the Environment Agency is pasted below which provides some additional information on OFAS and other matters,

OFA Steering Group

Oxford Scheme update

A423 bridge replacement

Oxfordshire County Council began the propping work on the A423 Kennington Railway Bridge in July.

Replacement of the A423 Bridge has provided an opportunity to design and build the bridge and the flood scheme together. This allows us to reduce disruption during construction and ensure the best use of public money. The updated design will use open channels instead of culverts to allow the flow of floodwater under the bridge. This will provide a better environment for wildlife and requires less maintenance.

The bridge is at the southern end of the scheme and during a flood, water would need to pass underneath it to re-join the River Thames. This capacity needs to be in place before the scheme is constructed to avoid increasing flood risk elsewhere. We also need to have all approvals, including planning permission and our Compulsory Purchase Order secured.

South Hinksey Archaeology

If you’ve been walking near South Hinksey, you may have spotted our contractors on site. We are carrying out archaeology surveys in a field near South Hinksey village to check whether the area is suitable for us to use as the main compound for when we construct the scheme. The archaeology surveys will determine whether there are any historical artefacts in the field. We want to ensure there’s no risk of us damaging any artefacts or remains. Once we have finished the investigations, we will remove our equipment from the site and reinstate the fields.

Kendall Copse Ground Investigations

To complement the new A423 bridge replacement, we are reviewing the design of the scheme around Kendall Copse, near Kennington.

From 10 August, we will be digging trial pits and drilling boreholes to understand the ground conditions beneath the site in order to finalise these designs.

Oxford Flood Incident Exercise

To ensure our flood protection plans are well-tested, the Oxford Flood Alleviation Scheme partners and emergency responders will be practicing their incident response plans on 20 August 2020.

The flood response exercise will consist of:

 •temporary flood barriers in South Hinksey and Bullstake Close

•pumps to remove flood water along Botley Road

Due to the current Government guidance on public gatherings, we won’t be able to invite members of the community to attend. We will be sharing updates on Twitter and Facebook as the exercise progresses. We will also share video footage of the temporary barriers and pumps so you can see our field teams in action.

Managing your flood risk

During the summer months, flood risk might be low on your list of priorities, but Environment Agency officers are thinking about it year-round. Throughout the year our operations staff carry out inspections and clear debris to keep main rivers moving. To report a blockage that could cause flooding call our 24 incident hotline: 0800 80 70 60.

You can also find out what maintenance is planned in your area: environment.data.gov.uk/asset-management/index.html

Stay prepared by signing up for flood alerts and preparing a flood plan: https://flood-warning-information.service.gov.uk

  

Want to know more?

If you have any questions or want to be added to our mailing list, please contact us at: OxfordScheme@environment-agency.gov.uk

A mistake

While we wait anxiously to see whether homes, businesses and roads will flood, work on the City Council’s extension to its Seacourt Park & Ride has come to a very wet standstill.

Building a car park in a flood plain is not sensible. Work having started as the wet winter season approached, the site is now a lake and work has stopped. The JCBs have been withdrawn onto the higher ground of the existing car park, and heaps of building materials are abandoned in the water. If the construction had been completed much of the extension would currently be under water. All this while the City is on ‘only’ a Flood Alert, the lowest category of concern.

The construction costs are likely to be much higher than estimated because of the disruption caused by flood events of the kind we’re currently witnessing. Councillors ignored the reality of frequent flooding here when they approved the planning application, and now we’re seeing the consequences. The last official budget figure we’re aware of was around £4million; we have heard, from a usually reliable source, that the cost may have risen to around £6 million, even before the present flooding of the site. Is this a sensible use of tax payers’ money?

Flooding at the site began on  Monday, so it’s already been a working week that it would have been out of action if it had been built – that means lost revenue and an unreliable service. And time and money would then be needed for pumping out, clearing up and very likely making repairs before the extension could be safely reopened to the public. Further expense and further loss of revenue. Because the site is so low-lying, this will happen quite often.

Because it’s a car park and not a field there is increased risk to the public and to vehicles, and it remains to be seen how well the Council is able to manage flooding here. The water came up quite quickly at the start of the week, and in the interests of safety the extension would have had to be closed before that to avoid cars getting trapped in flood water, i.e. sometime early last week. And remember we are only on a Flood Alert, not a Flood Warning. Were people to try to enter even quite shallow floodwater to retrieve their cars things could go horribly wrong.

In the second photo above, from yesterday, you can see two large pipes floating in the lake, one in the centre, the other far over to the right against the boundary fence. If the flooding worsens these could float downstream and jam under the nearby bridge under the Botley Road, exacerbating flood risk. Were it already a car park, for pipes read cars.

We, and many others, fought this ill-conceived project hard. We hope the City Council will even now abandon it and restore the site to its previous state, as a valuable wildlife habitat, including for the badgers who have been driven out. To press on regardless means wasting ever more of Oxford’s citizens’ money, putting off for years any possible financial return to the Council, and meanwhile potentially both increasing flood risk and posing a risk to life and vehicles.

Postscript on Seacourt P&R extension

Members of OFA steering group, along with Councillor Colin Cook, and Stephanie Ouzman (a member of MP Layla Moran’s staff), met with Council officers and their consultants WYG on 27 April 2018 to try to obtain answers to a series of questions about the proposed Seacourt P&R extension. Subsequent to the meeting there was a further email exchange and answers were provided to a number of outstanding points by the Council. We appreciate having had this opportunity for dialogue about the issues, and now feel we understand what is being proposed.

It’s clear from the response from the Council that the planning documents did not provide a clear reference to the use of an impermeable membrane at the site. It wasn’t spelled out in the application, and the documents give no details of the tanking and how this would work. This has now been explained to us.

We believe we should have been able to get answers, as of right, on points of issue like this through the planning consultation. The fact that we couldn’t was a failure of the process, and below the standards we have observed in other applications locally. The County (LLFA), Environment Agency and planning officer didn’t, in our view, fully understand what WYG were proposing – this is clear from correspondence with them during and subsequent to the planning process. Councillors, therefore, approved a proposal which had information gaps in it on flood risk, and which they couldn’t have fully understood. In our view this happened because the planning outcome had already been pre-determined, and our queries were ignored because the process was designed to secure a particular outcome. 

Now that we know what’s actually proposed, we don’t believe (as far as we can judge) that the development poses an immediate and direct flood risk to local properties, which is obviously a welcome outcome. But all development in Flood Zone 3B by its very nature creates a risk to the consistent and predictable functioning of floodplains. Hence planning policy, which incorporates learning outcomes from decades of previous developments in areas subject to flooding, prohibits such developments because the medium and long-term consequences can be unexpected and far-reaching. 

We believe the development is inconsistent with planning guidelines – building in the floodplain and Green Belt – but recognise the planning officer advised otherwise, and that Councillors agreed with his interpretation. We regret that the Secretary of State did not choose to examine this issue, and believe the Council’s decision sets an unfortunate planning precedent. We also remain unconvinced of the need case.

The car park extension will be an additional source of pollution during a flood, and there is no way to stop this. This is undesirable, and a negative environmental impact. The Seacourt P&R extension is just to the north of OFAS which has an ‘environmental vision’ aiming to improve freshwater habitat – a vision the Council signed up to. 

If the development goes ahead, we’ll be watching with interest to see how often if floods and how the local authority deals with this. At times of flooding the car park will be a potential source of risk to users and members of the public. We will also continue to be vigilant about further planning applications brought forward by the Council, as the process has left us feeling we can’t rely on the local planning authority, or members of Council planning committees, to safeguard the public interest. We hope public concerns will be better addressed should any similar situation arise in future.

NO NEED! Meeting to decide the Seacourt application today

NO NEED!

Two other posters which will be on display tonight

 

Meeting to decide the Seacourt application tomorrow – our posters for display

We will display these posters (and others) at the meeting of the Oxford City Council West Area Planning Committee to decide the Seacourt park and ride extension planning application, which (as you may have gathered by now) we oppose. The meeting is tomorrow evening (12 December) in the Assembly Room at the Town Hall and is open to the public; if you oppose the application please do attend. The meeting starts at 6pm and this will be the first application to be considered.

 

 

Risk of local property flooding

From the Planning Officer’s report to the West Area Planning Committee, December 2017:

“9.149. During the consultation process, reference has been made to the suggestion within the Factual and Interpretive Ground Investigation Report that the proposed drainage strategy will require the use of lime stabilisation to avoid damage to the paving within the car park expansion from changes to the clay layer below ground and that this needs to be given further consideration as part of any drainage proposals for the site. The concerns raised are that lime treatment is likely to have an impact on the permeability of soils below the car park, and therefore needs to be appropriately considered. 

The applicant has confirmed that the surface water drainage strategy has been designed as a tanked system which assumes no infiltration below the attenuation layer, with all storm water discharge from the site via a controlled outfall into Seacourt Stream. An impermeable membrane is included within the construction to prevent water saturating the clay. The underlying clay is of a low permeability whether lime stabilisation is employed or not, and it is envisaged that the attenuation will operate effectively in either scenario.” [emphasis added]

There is no mention in the Application of tanking, nor of an impermeable membrane. We have therefore not known of this till very recently and had no opportunity to comment. While there is little or no detail, the idea that the car park may be separated from the underlying groundwater table, as this implies, raises an extremely serious question. That is, where will the displaced groundwater go? This is a lot of water over such a large area. It is likely that it will cause a significant rise in groundwater levels around this low-lying site. This could cause (new) groundwater flooding within houses (and gardens) nearby. No decision should be taken until the details of  what is planned are made clear, appropriate calculations and modelling done, and presented as part of a further revised Flood Risk Assessment.

[By the same token, when it rains, water will be trapped within the tanking , draining only slowly – more pumping needed?]

Scheme to reduce flooding in Oxford will NOT put downstream at greater risk 

An independent review of the Oxford Flood Alleviation Scheme, commissioned by Vale of White Horse District Council, has confirmed that the proposed flood alleviation scheme will have no impact on communities downstream in the Vale or South Oxfordshire.
The Oxford Flood Alleviation Scheme will be approximately three miles long and will run from the north of Botley Road to re-join the River Thames near Kennington.  The scheme will reduce the risk of flooding from the River Thames to all homes and businesses in Oxford, as well as to services and major transport routes into the city, particularly around Botley and Abingdon Road.  This will help avoid a repeat of the disruption and damage caused by floods in 2007, 2012 and 2013/14.
Communities downstream were concerned that the Oxford scheme would increase their flood risk.
In 2016 the Environment Agency produced technical modelling using sophisticated computer programmes which showed that the scheme would not change flood risk of communities downstream. As with all Environment Agency modelling this was independently checked.
In 2017, due to local concerns, Vale of White Horse District Council commissioned independent expert, Water Resource Associates, to further review the work carried out by the Environment Agency.
This independent review confirms that the Oxford Flood Alleviation Scheme will not put communities downstream at any greater risk of flooding. To read the full Water Resource Associates’ review visit whitehorsedc.gov.uk/OFAS.
Cllr Matthew Barber, Leader of Vale of White Horse District Council, said: “This is very positive news.  Although we have always been supportive of the Oxford scheme it was important for us to listen and respond to our residents’ concerns.  We’re pleased that the independent review findings confirm the Environment Agency’s modelling, providing much needed reassurance for downstream communities that they won’t be impacted by the new scheme.
“We know communities by the River Thames will always have concerns over flooding and we will continue to work with them and Environment Agency on feasible and appropriate flood prevention projects, such as the St Helen’s Mill scheme in Abingdon.”
Dr Harvey Rodda from Water Resource Associates said: “After receiving all of the documentation from the Environment Agency and their consultants working on the OFAS we were pleased that a thorough investigation on the potential downstream impacts had taken place and the results showed there would be a negligible impact of flooding on the areas along the downstream reach of the River Thames from Sandford to Mapledurham.”
Jo Larmour, Project Director at the Environment Agency said: “The Oxford Flood Alleviation Scheme will have a positive impact on people and communities outside of Oxford. The scheme will reduce disruption to roads and the railway during flooding, a relief to those who commute into Oxford or travel on surrounding transport links. This will also benefit the approximately 7 million people who visit Oxford every year.”

Seacourt P&R in the Oxford Mail; smart signs, plus risk to life

This article in the Oxford Mail talks about the possibility of  ‘smart signs’ – electronic boards – on the ring road, to alert drivers to where there are empty park and ride spaces around Oxford. This could obviate the (claimed) need to increase the number of spaces at Seacourt, instead pointing drivers to (say) nearby Redbridge. According to an earlier report in the Oxford Mail there is apparently so much spare capacity at Redbridge that the City Council proposes to remove 270 parking spaces, and is quoted in the newspaper as saying that the loss of these spaces would be ‘marginal’.

It seems to us to be inconsistent for the City Council to argue that removing 270 spaces at Redbridge is perfectly ok, while at the same time arguing a burning need to build new spaces at Seacourt – in the floodplain, on Green Belt land, contrary to local and national planning guidance and, as far as the present application goes, creating a potential risk to life (see towards the end of the first newspaper article and our previous post). Never mind the cost, which has already risen from about £2million to over £4 million.