Irresponsibile or Incompetent? Local councillors role in the Bridgwater Tidal Barrier

An old boss of mine says unintended consequences is merely the failure to adequately consider the implications of the decision being made.

The location of the Bridgwater Tidal Barrier (BTB) is probably the most significant decision Sedgemoor District Council has made in many years. Rarely can such an important decision have been made with so little debate. If it’s in the wrong place we and the following generations live with the consequences for the next 200 years or so. No one is giving us another one if its wrong.

On the 26th July 2017 a full Sedgemoor District Council meeting agreed the location of the Bridgwater Tidal Barrier. This decision according to the minutes was apparently waived through without discussion. That the EA and SDC gave a superfical 3 page briefing document with so few key facts indicates just how confident EA and SDC officers felt able too simply ignore the longer term collateral environmental and economic impacts of this scheme. It is a clear indication of the low esteem our councilors are held in. Councillors lack of oversight of this scheme does indicate the officers probably wernt wrong. Silent oversight committees seems to have presided over continued and unsatisfactorily explained cost rises. The cost almost doubled in the the six months after the decision was made. Barely a word was said.

The Issue

Abandoning 1,400 acres of valuable land next to a motorway junction capable of supporting £1B of future investment (jobs) whilst unnecessarily forcing future housing onto the Quantocks foothills extending Bridgwater to absorb Cannington, Spaxton and North Petherton.

This decision  will be seen as one of the most irresponsible and  reproachable acts by councillors of any  local authority at any time. SDC knowingly made a decision to convert the Parrett Estuary into an Intertidal Habitat and behind the the secondary flood defence create more areas of habitat suitable for freshwater mosquitios such as the Zika and Denge carrying Asian Tiger Mosquito to take up residence.

Limiting economic expansion, building on the Quantocks, poisoning the fresh water ecology of Chilton Trinity and Pawlett Hamsand and creating a future health hazard is hardly what we people voted councillors into office for.

  • If they did know why did they do it?
  • If they didnt know why not?

Why is this case?

The BTB design uses farmland downstream of the barrier to allow incoming saltwater to spill over riverbanks onto the farmland. It destroys the economic value of around 2.400 acres of land either to continue as low-grade farmland or 1,400 Acres of that total to the south of the Parrett providing land for nearly a £1B of economic development accessible from J23. Would any town throw such an economic legacy away with so little concern? Bridgwater has. The longtime environmental Impact of this scheme is equally as bad; the land being flooded will ultimately become saltmarsh and a large part of the local Quantock foothills unnecessarily developed

The December 2018 public consultation asked for feedback on three basic points

  • The details of the proposals for both the barrier and the downstream flood defences.
  • How you think the proposals may affect you, your land or your business.
  • What additional improvements you would like to see delivered as priorities, in addition to the barrier and the downstream flood defences, subject to funding.

Context

Large civil engineering projects influence long-term economic development as we have seen with development taking place around our motorway junctions; the proposed Bridgwater Tidal Barrier (BTB) will influence Bridgwater’s future development in a similar way for at least the next 200 years. The Bridgwater Vision published in 2015 and referred to in the presentation  identified land for future development most of which is either now approved or starting to be built out under the local plan. Bridgwater is already reaching the limit of land that can be easily accessed from the town and the M5.

Assuming Bridgwater continues to develop economically at even half its present rate, during the design life of the BTB, an additional 25,000 houses will be built and together with land for employment and Bridgwater’s footprint will grow by around 40%.

Under the present BTB scheme low quality farmland directly beside Junction 23 that could have provided space for at least £1B of economic development, housing and jobs will be lost to the town. Alternative land over the next 100 years will need to be found and that will invariably mean development moving on to high quality agricultural to the south and west of Bridgwater. We will build on the land that feeds us whilst living ever farther from planned and established centres of employment to the north and north east of Bridgwater (Horsey). Building at Horsey will require a new bridge over the King Sedgemoor Drain; money that could be used to cross the Parrett and bring forward a much needed northern bypass.

Location

The reader should take cognisance that the two options studies done for this scheme, the first included highly improbable options such as the Bridgwater Bay power lagoon and outside the influence of the authors. The second option study looked at the same solution at a limited number of locations and would always arrive at the narrowest part of the riveras the prefered solution. It was a superficial study and lacking rigour and at the time of this note the final information used by an SDC sub group remains unpublished despite an FoI request to Sedgemoor District Council remaining outstanding.

Other options and locations to protect Bridgwater and the downstream villages were available but not considered.

Description

The Bridgwater Tidal Barrier is a 7mile long inland tidal surge flood defence scheme with a 100 year design life based on sea level rising around 800mm during this period. Similar to the current Thames Barrier it consists of a two elements.

  1. Riverbanks profiled to preferentially spill seawater, during extreme tidal surge conditions, onto farmland at Chilton Trinity and Pawlett Hams.
  2. A small double vertical floodgate barrier located in the industrial and employment Express Park area of Bridgwater and approximately 1 mile from the town centre.

The replacement Thames Barrier will be sited more conventionally at the mouth of the Thames; Combwich is Bridgwater’s equivalent location.

Key features

  1. The riverbanks are expected settle and need reconstructing every 35 years
  2. The height to which the riverbanks can be raised is limited by the poor ground conditions.
  3. Although needed no provision of any kind for a replacement is considered.
  4. Contaminates around 2400 acres of farmland with salt water
  5. Constrains economic development to the northwest of the town.
  6. Significant loss of existing freshwater habitat in line with managed realignment policy 7d39 of the Shoreline Management Plan to create an intertidal habitat.
EA DIAGRAM SHOWING SALTWATER FLOWING ONTO FARM LAND

Operation

The closure of the barrier at low tide creates a separation of the two types of water that use the River Parrett. Upstream freshwater from the Parrett and its tributaries such as the Tone; Yeo and Cam will be impounded behind the closed gates. Downstream the freshwater will finish emptying into the Severn and the then the empty river filled with seawater on the incoming tide.

All flooding shown downstream of the Bridgwater Tidal Barrier will therefore deposit salt water onto the land. This is saltwater and the impact should not be confused with the 2014 event.

The land in question at Chilton Trinity has not been flooded with salt water in this way within living memory.  Pawlett Hams was briefly flooded in the early 80’s and flooded Pawlett from the north where no flood defences are planned.

Summary

What is clear is that considerable ambiguity remains in the proposal. Many issues are simply ignored or the messages contradictory. The following summary and notes provides some comments that should be addressed.

It is disappointing that such an important scheme appears to have been given so little strategic thought whilst the barrier appearance and immediate landscaping seems to have received considerable if unsuccessful attention.

Clearly the priorities of the design and client team are not those of the ratepayers who do not need a solution where the medicine kills the patient which is what we appear to have.  

River Banks

One consistent underlying theme is that once the barrier is built the land to the north and south, Chilton Trinity and Pawlett Hams, will ultimately become intertidal habitat in line with existing published policies.

The key supporting facts are

  • The cost estimate that does not include for future riverbank reconstruction
  • Planned flooding of agricultural land with saltwater.

The claim made “Bridgwater and the surrounding area will be better protected against a severe flood by building the barrier and improving the downstream flood defences. These works will also maintain the current standard of defence to agricultural land”.is misleading to landowners indicating that farming will simply carry on as normal. With the frequency of saltwater flooding increasing the land will not support the type of grass needed for agricultural. Areas of Norfolk are still recovering from single sea water incursion 65 years ago.

Borrow Pits

No location for the pits was given, which side of the secondary flood defence. It would not be unreasonable to assume between the river bank and the secondary flood defence. A rough estimate would indicate that the scheme will need around 100,000m3 to 150,000m3 of clay creating a large open area (7-8Ha) of stagnant water that will through our now warmer summers become more saline as they will operate as a large evaporation pond. That mechanism does not allow the wildlife enhance described to occur.

Locations were shown to stakeholders but not the public

Environment

A number of claims are made regarding the lack of environmental impact that this scheme has on the ecology however changing the habitat from freshwater to saline will fundamentally change the area in line with the published strategy of changing the land to an intertidal habitat.

2,400 acres of fresh water habitat is destroyed through repeated seawater flooding.

Cost or Intention

An estimate of £94M is given in the EA presentation. Through a FoI request (03 April 2018) The EA provided an estimated whole life cost closer to £160M. That estimate assumed £12.4M Net Present Value or £55M cash cost over 100 years including for maintaining and rebuilding the riverbanks that is around 4x the value of the land. Economically this statement on maintenance costs makes funding the future bank rising impossible. If the circa £100m estimate is correct this would cover the gate maintenance and not the riverbanks. 

The expected need to rebuild the riverbanks twice in the 100-year design life is not mentioned in the presentation and the assumption must be that the intention will not become reality and would conflict with clauses 1.10.1 and 1.10.2 of SDC’s Parrett Estuary Flood Risk Management Strategy

The whole life cost of the scheme is either

  • £100M with one set of the riverbank improvements at the time the barrier is constructed.
  • £160M with three sets of the riverbank improvements including the time the barrier is constructed and subsequently at 35-year intervals after that. That must be the budget.

Did nobody ask why?

Collateral Impact

This scheme is presented at completion in 2024 and looks only at immediate local impacts.  Construction will have immediate and long term wider negative consequences for Bridgwater none of which have been raised or addressed despite written assurances that that would not be the case.

Economic Impacts

  • Loss of 1400 acres of key land suitable for £1B of economic investment for housing and industry that is directly accessible to Junction 23.
  • Creation of a working flood plain over which a potential bypass might need to be constructed.
  • Increasing separation of housing from employment by forcing development elsewhere.
  • Loss of economic food production on prime agricultural land
  • The loss of in existing land values of around £12m and potential bankruptcies where the land is used to secure business loans.

Environment Impacts

  • Destroys 2400 acres of fresh water habitat through deliberate seawater flooding initially during extreme tidal events but ultimately becoming within the normal tidal range.
  • Forces development to take place on high quality agricultural land to the south and west of Bridgwater.
  • Forces apart residential and employment areas with a consequent long term cost to the economy and the environment.
  • Places increased demand on the A38, A39 and Kings Drive as industrial development is forced east to Horsey and to the approved BAE industrial site.

Barrier Superstructure

The barrier superstructure is 2 to 2.5 times higher than it needs to be and lacks any shape that reflects its functionality. It achieves the rare combination of being both pretentious and mediocre. With a structural volume that must be four times what could be reasonably required to support its function it is bloated, unnecessarily expensive and will be difficult and expensive to maintain. Overhanging shapes require specialist access equipment for maintenance. Everything on the structure seems designed to cost more than is necessary. Its appearance seems to owe more to Mr Blobby and the Teletubbies than the Falkirk Wheel, it doesnt do anything like the Falkirk Wheel so hardly a tourist attraction.

The very large ovoid bridge structure will be particular difficult to maintain, it will be almost impossible for safe inspection of the lower quadrants to be made or worked upon. The form of the structure indicates little attention appears to have been taken with regard to the Construction, Design and Management 2015 regulations with regard to the safe operation and maintenance

The poor design of this structure extends to the gates, rather than protect the gates from the salt loaded wind driven rain, the site is classed as a marine environment, rain will be spilled from the ovoid bridge onto the gates increasing maintenance and reducing the life of the gates.

As a piece of architecture and a piece of engineering this structure almost certainly fails on cost, function, operator safety and buildability.

Storage Buildings are provided when the EA has a depot nearby at Bradney.

  • Did no one ask why we need additional buildings at the barrier site?
  • Presumably they would also attract rates?

Sustainability

The lack of sustainability in this project is very concerning;

The decision to excavate burrow pits to reduce construction traffic seems highly questionable. “Where possible, we will excavate material locally from ‘borrow pits’. This will minimise the need to bring in material to build the new downstream flood banks and reduce construction traffic.”

The EA was more than happy to bring excavated material from its Cannington flood project to Chilton Trinity yet the more sustainable option of building the banks over a longer period using spoil from building sites is not considered. It’s not as if the defences need to be at their final levels until the last planned rebuilding of the banks 35 years before then end of the design life. This work could be done on an opportunistic basis over the next 50 years or so in a sustainable cost effective method by local contractors.

The continuing reference to 2055 that is key date in the shoreline management plan indicates thatany future raising of the river banks is unlikely to occure.

This process would also assist in maintaining accesses and local resources able to respond to urgent requirements such as a breach in the river bank.

Finally just to prove the point the EA/SDC presented on page 7 of the stakeholder presentation three images of unrelated events to support its postition.

  • West Quay collapse, an old wall collapsed when it got too much water behind it; we see thse failures alongside our roads all the time but we dont try and link them to climate change or a tidal barrier.
  • The 2014 flood was a pluvial (rain) event and the Bridgwater Tidal Barrier is not designed to mitigate a repeating event. There is clue in the word Tidal. Unfortunately many people in Bridgwater and the surrounding area believe that it is part of a pluvial flood defence scheme.
  • one was applicable
WEST QUAY & 2014 ARE NOT TIDAL EVENTS

Perhaps an SDC, Town or county councillor reading this might decide to ask some serious questions about this project, one can only hope.



Flood protection, wildlife & environment is always a one sided view.

The impact of wildlife organisations on locally managed flood projects is a concern. They seem to be free to make unsubstantiated statements whilst pursuing their objectives with little public visibility, criticism or professional oversight and it is a growing problem.  It is a situation becoming increasingly familiar and yet another example of our growing democratic deficit where minorities impose their ambitions on the majority. The Somerset  Levels,  the Parrett Estuary and Bridgwater’s need for a flood defence from the sea has brought many of these parties with their own agenda to one location each focusing on what they consider to be important. Bridgwater seems to be well down the list of importance despite the planned construction of the Bridgwater Tidal Barrier. The purpose of this article is to provide an explanation as to how this is happening.

Context

Bridgwater currently builds around 500 houses a year and if that rate continues at even half that rate for the next 100 years we could expect to see the number of houses in Bridgwater rise by 25,000 taking another 700Ha (1,700 acres) of  land for housing and a further 300Ha needed for employment. This 1,000Ha’s  will see Bridgwater’s existing footprint grow by at least 50%, The 25,000 houses and associated economic development will generate perhaps 300,000m3 of clays and soil waste.

With flat and level land needed for employment land at the old BAE site and at Horsey offer the only other viable employment options to Bridgwater and they are to the northwest. New housing will be forced onto good quality farmland south along the A38 swallowing up North Petherton and eventually meeting Taunton coming the other way and to the west developing the land between Bridgwater and Cannington. Bridgwater will consume its high value agricultural land on the hills as it, like the rest of the country, continues to build our outdated ideas of housing.

Bridgwater will therefore become an even more difficult place to live and work as the gap between residential development and employment continue to grow. Every day a large part of Bridgwater’s population will get up and drive along the A38 and A39  to get to work. Bridgwater will not even start considering a bypass until 2040.

Apart from the normal lack of imagination by planners and developer’s Sedgemoor’s (Bridgwater) greatest problem now appears to be the wildlife and flood pressure groups that seem to take an extreme view in the pursuit of what they consider to be in their interest. They show little tolerance or understanding that people also live on the Levels and in Bridgwater and ignor the EU directives that accept people must come first. The true impact of their objectives is concealed and never addressed.

These organisations also seem immune from any need to consider facts in their statements whilst criticising property developers for the smallest omission. The irony that is they now ape those same commercial organisations in assembling land and changing its use without considering its long term impact on the wider local population and  it should be lost on no one.

Some typical examples

Steart Peninsula

The local economic benefits alluded to as part of the original Steart Peninsula planning application remain unproven and therefore represent little tangible benefit to the local population yet quoted as fact by The Severn Vision statements.

The Severn Vision

The Severn Vision

This plan will expand the existing saltmarsh by 833% around the Severn Estuary and in Bridgwater’s case large areas of agricultural land removed from food production and converted from a freshwater environment to a saltwater one (intertidal habitat). To date two phases have been completed; The Steart Peninsula and the RSPB reserve (funnded by Bristol Ports) both of which remove economic activity and destroy an existing habitat to create another. A process little different from modern housing development. Whilst an argument might be made on the basis of geography for these two areas to be returned to the sea no such argument exists for the destruction of Pawlett Hams and Chilton Trinity including areas of the SSI.

This is a process promoted by the following organisations

  • Wildlife and Wetlands
  • The Wildlife Trusts
  • RSPB
  • National Trust
  • Campaign for Rural England (CPRE)
  • Severn Rivers Trust

With regard to Bridgwater it makes claims regarding carbon savings whilst ignoring the collateral effect of moving Bridgwater’s housing developments onto higher quality agricultural land and increasing commuting distances. Also ignored is the loss of food production on 5,000 acres of land and the transfer of that food production overseas. It is particularly misleading in its statements with regard to Bridgwater providing no supporting evidence as to the negative benefit that it has considered in any balanced and holistic way. It is completely one sided yet already two key elements have been delivered, Steart Peninsula  and RSPB  reserve. The Bridgwater Tidal Barrier will deliver the southern land at Chilton Trinity and Pawlett Hams .

Bridgwater Tidal Barrier

The Environment Agency and Sedgemoor District Council’s Dec 2018 public consultation made a claim with regard to the lack of any environmental impact of this scheme. The EA and SDC have not considered environmental impacts beyond the immediate area of the scheme despite this scheme  imposing restrictions on economic development forcing residential development to the south and west of Bridgwater and employment to the northwest of the town.

It is worth noting that HPC looked at issues far beyond the immediate area of the power plant when it did its enviromental impact assessment.

Environmental Impact Statement

This statement above  cannot be true as

  1. Seawater is shown overtopping the river banks onto the existing farmland, the fact that it is seawater is misleading.
  2. The farmland at Chilton Trinity and Pawlett Hams will be poisoned for agriculture through the introduction of saltwater
  3. The existing wildlife that requires a freshwater environment will be destroyed.
  4. The location of the borrow pits, which side of the secondary flood defence, was not shown. The plan to excavate 100,000m3 of material will create a lake of nearly 13 acres that  will act as a reservoir for saltwater.
  5. 1,400 acres of high quality farmland suitable will be unnecessarily developed invariable towards North Petherton and Cannington as this scheme will convert  1,400 acres of low quality farmland that could have been used to saltmarsh.
  6.  100 years of lost food production on 2400 acres of farmland.
  7. 100,000m3 of clay will be unnecessarily excavated from the  land  being protected whilst during the same period 300,000m3 will be produced as waste through normal housing and industrial construction activities. (the secondary flood defences do not need to be completed to the full height during intial construction
  8. Denying economic development in the north-west will increase commuting efforts in the local community generating avoidable C02; the scheme ensures the increased separation of employment areas from housing.

The claims regarding this scheme are questionable at best and the lack of information misleading at worse. The extract from the EA/SDC public display  indicates a plan to create a  stepping-stones for species that are not identified.

Campaign for Rural England (CPRE)

The CPRE’s support for The Severn Vision that results in the wholesale destruction of a large area of our existing productive landscape and the equivalent of 10 500 acre farms is not what we imagined their core mission to be that says

“We campaign for a beautiful and living countryside. We work to protect, promote and enhance our towns and countryside to make them better places to live, work and enjoy, and to ensure the countryside is protected for now and future generations.”

How allowing saltwater (seawater) onto productive farmland that has taken 500 years to remove the salt from seems a strange way  of protecting our countryside.

Somerset’s Wild Trust (SWT)

Another supporter of The Severn Vision.

Somerset’s Wild Trust’s  website says

Since the 2013-14 flooding events, the dominant narrative in the floodplains has focussed on hard engineering schemes and dredging to reduce flood risk, overlooking flood risk reduction techniques that work with nature and provide a range of benefits to society. A future is developing where more public money will be spent on fossil fuel intensive dredging and pumping, to further drain the peat soils of the Levels, thus releasing more carbon and exacerbating climate change. As peat is drained, it shrinks, lowering land height and making the area ever more vulnerable to extreme weather. Well-informed debate on the future of Somerset’s low-lying areas in the face of rising sea level is limited, so a further vital part of our work on the Levels is to communicate a more optimistic narrative which gives nature its proper value.

This statement ignores that the Somerset Level’s is an artificial environment that needs regular maintenance and seems to conflate the need to dredge Somerset’s rivers and the need to get pluvial flows from the upper Parrett catchment areas to the sea bypassing the levels storage with an idea that somehow this process is designed to shrink the peat. “A future is developing where more public money will be spent on fossil fuel intensive dredging and pumping, to further drain the peat soils of the Levels, thus releasing more carbon and exacerbating climate change” is a particularly spurious and misleading statement. It sounds like people are secretly pumping water off the levels as some sort of conspiracy.

Anyone with any knowledge of the Levels would know that retaining water levels is just as important to the Levels as draining them. No one is going to drain the peat. Well informed debate requires informed knowledge and that is clearly not the case with this statement by the SWT.

FLAG Flooding on the Levels Action Group

FLAG reflects its single issue origins seemingly taking its position on Somerset’s farming industry geographically from the lands relationship to Moorland and what is best for Moorland.

A post (Nov 2018) supporting Somerset’ s farming industry on the Levels was made by FLAG making Brexit the largest threat to farmers in anticipation of a nonexistent trade deal with the US; no doubt the cause of the 2014 flood and global warming will in time also be subscribed to Brexit.

FLAG’s postion downstream of Moorland at Chilton Trinity and Pawlett Hams is quite different.  Flag is altogther less compasionate regarding the farmers there having their land flooded with saltwater to alleviate upstream flooding. Concern is  simply dismissed by a statement worthy of Marie Antoinette “let them raise salt beef or lamb”. It  completely ignores  that the Bridgwater Tidal Barrier has already destroyed  land values for 2,400 acres of land and food production we might  have gained. Reverse nimbyism seems to apply; as long the flooding is on someone else’s land FLAG appears to be happy whilst refuses even the smallest tacit support  for or willingness to consider alternatives tht might have a better outcome for the wider community.

Conclusion

Whilst our wildlife organisations may have started with good intentions what is clear is that many people associated with these organisations simply don’t understand the mechanisms of the Somerset Levels, the impact of what they propose (The Severn Vision)  and in most cases don’t care if it doesn’t suit their agenda. They fail to consider that ultimately the economy pays for everything and destroying local economies will ultimately call into question the viability of protecting our environment; the ratepayer maintains the roads used to get to our wildlife sites and will pay or make a significant financial contribution to the cost to the current planned defences and the their subsequent replacements. A case of shooting the goose that lays the Golden Egg of in this case chasing away industry and people.

It is clear that many organisations support the existing proposals to turn the Parrett Estuary into a saltmarsh. The  decision by SDC and the EA not to commission an economic impact assessment has allowed those organisations and the Environment Agency to  create the worst possible long term economic future as there is no assessment mechanism other than the government  investment rules to measure the value of this scheme.  Allowing the  undermining Somerset’s agricultural industry, wasteful development and not working towards an integrated low energy society is not what we should be doing.

Bridgwater Tidal Barrier Final Public Consultation

Ahead of the forthcoming last public consultation on the Bridgwater Tidal Barrier (BTB) the rate and tax payers might consider asking what becomes of Bridgwater after the BTB reaches the end of its design life?

The answer is simple.  

if there  is no barrier capable of keeping the rising sea out there will be no house insurance, no mortgages and Bridgwater the town will not be a viable place to live. 

Our present proposed EA flood defence scheme is based on retreating as far back from the sea as we can, it deliberately  puts our backs to the wall  On one side of the barrier we will ultimately have the inter tidal habitat (the sea)  and on the other our housing and industry.

No space is being provided behind the proposed barrier to create another bigger one. As a consequence there will be nowhere to go with a replacement that does not have a huge and unnecessary price tag. There is an irony that land at Chilton Trinity returned to the sea under the present scheme  and the planned managed realignment in 2055  will be inadvertently reclaimed  under a downstream replacement barrier albeit land now poisoned with salt.

With sea level rise continuing for hundreds of years past the design life of the BTB one would expect that as responsible people we would give some consideration to what happens next. Unfortunately, like so many things in need of fixing and investment we seem content to kick the problem into future refusing even to consider how we might make some provision to help those that follow us.

Many years an Arup engineer called Poul Beckmann wrote  the opening sentence of a  document with the line “Human nature is that we put off until tomorrow what we should do today”. Never has that been more true today than in Somerset. Somerset’s failure to develop a realistic, affordable and sustainable long-term strategy is unforgivable.  It really is time for some of the promises made by our political leadership on this issue to be delivered and people stop making excuses why things cannot be done. Simply working our way through the Somerset 20 years plan and saying the future is not our business is irresponsible and unacceptable.

what was the question?

The SRA was asked “What is the SRA and its partners working assumption for the replacement of the existing scheme and barrier?

The written answer received from the SRA  answer is in blue

From day one, the tidal barrier will be designed in such a way that it will still provide a 1 in 1,000-year standard of protection in 2125. The design includes an allowance for climate change up to 2125.

  • Climate change does not stop in 2125!!!! 
  • 1:1,000 sounds good but its just the margin on the starting point and degrades over time. The Dutch use 1;10,000 and maintain it as the level of protection.

The downstream defences will be designed in such a way that they will still provide a 1 in 200-year standard of protection in 2055, with allowance for further adaption for climate change over time.

  • 2055 is important because this is the date from which managed realignment is implemented under Policy 7d39  of the Shoreline Management Plan.

EA explaining the scheme in 2017

It is to be expected that any piece of infrastructure would need updating after 100 years. We cannot decide now how future generations may wish to live or what their priorities for infrastructure will need to be. This is why, for example, there are plans for the Thames Barrier to be re-built in future decades but decisions on exactly where and what will be required are deliberately being left for later.

  • Building the barrier in the town as planned does not  give those in the future choices but leaves them no choice to but to go downstream and  use land we have previously given back to the sea and to abandon the £100M investment the present scheme will have cost.
  • The response attempts to conflate the need to replace the  1970’s Thames Barrier as a reason not to make provision today for a replacement  in Somerset. if you know you have to replace something why would you not plan for the replacement? Its an excuse. 
  • We should be learning the lessons of the past rather than making a  virtue of repeating the failures that the SRA reply implies.

The Thames Barrier Myth

The continual portrayal Thames Barrier shown on TV as an iconic single barrier solution is misleading; the barrier is actually part of the Thames Estuary flood defence system comprising not one but eight individual tidal barriers that all shut together. Five of the eight barriers are closer to Bridgwater’s  situation than the “Thames Barrier”. They are however where they should be at the mouth of the rivers they defend not 5 miles upstream as with Bridgwater’s Tidal Barrier.

Thames Estuary Flood Defence

Using the Thames Barrier as an excuse for not planning a replacement in Somerset is particularly disingenuous  for a number of reasons.

  1. Nearly 60 years ago  when the Thames Barrier was designed climate change was not understood as it is now. There was little provision for sea level rise just the post Ice Age tilt of the south of England to consider.
  2. The  Thames Barrier is upstream of what were active docks  that had navigation rights in the Thames Estuary.
  3. In Somerset we have a topography in the form of the Polden Hills, Pawlett Hill and Stockland Bristol that we can link and use to our advantage.  London does not have such a luxury.
  4. All the Thames Barrier replacement options  move the replacement barrier  downstream perhaps as far as Tilbury. (July 2016 update)
  5. The  most frequent use of the Thames Barrier is now the management of fluvial flood water rather than tidal surge. Something Bridgwater is not designed to do.
  6. Sedgemoor District Council is able to reserve space for a bridge over the Parrett south of Dunball should its not be doing the same for a replacement barrier?

The collective response is No ; there is no plan.

The SRA, EA and SDC were conformed as having contributed to the response

Bridgwater Tidal Barrier; the Questions the public need to Ask

Once  the question “how will the proposed Bridgwater Tidal Barrier be replaced?” the present  scheme simply looks out of date and poor value for money.

The Bridgwater Tidal Barrier is repeating the same mistake as was made with the Thames Barrier system setting it as far upstream as possible. Because of the selected location  a replacement would like the Thames Barrier have to go downstream towards Combwich. Confused? We should be.

When you go to public consultation some questions worth asking;

  1. How will the proposed Bridgwater Tidal Barrier be replaced?”
  2. What becomes of Bridgwater after sea level rise exceeds the design basis of the Bridgwater Tidal Barrier?
  3. Why is there no long-term plan or vision for what comes next?
  4. Why is the ratepayer required to provide money to raise river banks money protecting land at Chilton Trinity when the planned sea water flooding will make it of no economic value?
  5. Why is not improving fluvial flow in the river system  part of the scheme?
  6. Why did the cost of the scheme almost double after the location was decided on?

Sustainable Flood Defence

The UK has a serious problem with leadership and sustainable construction where flood defence is concerned. There is a profound lack of critical thinking in the delivery of future UK flood defences and an unwillingness by agencies to get their  hands dirty at a local level. As a consequence government continues to fail regarding sustainability and value for money; taxpayer funded agencies seem unable or unwilling to work together.  It is a situation compounded by wildlife and environmental organisations who have seen an opportunity to gain control of and modify land in much the same way that monasteries such as Glastonbury once did.

Flood defence schemes are invariably seen in terms of a definable project that can be closed rather than the first step of a sustainable long term solution. The protected community needs to live with and manage these schemes  for 100’s of years after they are built. Our thinking on delivery is just too short and too expensive when it is a 300 year or so problem and especially when the initial solution only has a 100 year design life; it makes little sense. There is an obvious gap. That gap  means that today’s options should at least consider what happens next. Should we really  be adopting a solution today requiring the construction of a  replacement barrier tomorrow rather than a scheme today that has  provision or a plan for extending it already built in? Our current scheme takes planned obsolescence to a new level.

We should not be closing out future options for the generations that follow and we should follow our own rules for sustainable development

“Sustainable development is development that meets the needs of the present, without compromising the ability of future generations to meet their own needs.”

Delivery of the Bridgwater Tidal Barrier continues to be an exemplar of non-sustainable thinking. Part of the scheme requires the river banks between the tidal barrier and the village of Combwich to be maintained. The EA’s plan to do this work as part of the barrier construction contract. Material is to be dug from the adjacent protected fields  and where a future Northern Bridgwater Bypass might be routed.  Sedgemoor District Council (SDC) have protected in the Local Plan a potential crossing point on the River Parrett just south of the  A38 roundabout at Dunball.

Clearly excavating Chilton Trinity’s fields and creating a series of salt water pits that creates an ideal future breeding ground for salt marsh breeding mosquito’s is not what people have considered the consequence to be. It is far from impossible that in a generation Chilton Trinity and Combwich may ultimately become uninhabitable because of this excavation process rather than from the increased flood risk. Managing mosquito borne diseases may well become the larger challenge in low lying areas as our climate warms up. It is difficult to see how the EA could contemplate the creation of such a situation.

With whole life costs of the Bridgwater Tidal Barrier reaching £100M for a barrier, secondary banks and the raised river banks; banks that need continual raising means we need to consider modification of the delivery model to get the costs of this project under control.

That whole life cost  also ignores the 100 year economic impact,  both locally and nationally, of losing 1000’s  of acres of productive agricultural land  notwithstanding the questionable morality of a food importing country  choosing to export more of its food production offshore. 

If we are going to build the solution we have we need better and more economic delivery solutions than is currently proposed. We can then at least  ameliorate the present situation with a better delivery system.

Brexit allows the modification of the EU water and waste directives  that have now been written into UK law. We can now change the way in which we manage waste for the better.

Sustainable Construction

Every year Sedgemoor will build 5-600 houses and the excavation of foundations and drains for each of these houses will create around 15-20m3 of waste material (clay) suitable for re use as bank raising fill material. Sedgemoor’s  planned housing developments  will create around 9,000m3 per year that currently must be paid for to be disposed of. Housing developers could supply all the material needed to raise the banks. That is sustainable construction.

Over the 100 years life of the barrier there could be as much as 900,000 m3 of material we need to find a home for; material that could be used to build up the banks and preserve the land we have at Chilton Trinity for future generations. Even if the volume is  only 10% of the possible amount its probably enough to avoid digging up land at Chilton Trinity.

Under present EA proposals the EA is going to pay landowners for material that other organisations with similar material must pay to dispose of. We are meant to be reducing this sort of activity not making the situation worse.

We simply don’t need to get all the work in place in 2024; we need just enough to maintain the flood defence need and then use local resources to progressively deliver the longer-term solution with a local benefit to the economy. This work could be collectively done by local contractors under the supervision of either the EA or the Drainage Board. There is simply no engineering need for the EA to wantonly and unnecessarily destroy our landscape when cheaper and more sustainable alternatives are available.

NB there is only an intent to continue to raise the river banks 

To put this into perspective that recycled material would

  • build a bank 5m high bank from the Bridgwater Tidal Barrier to Combwich.
  • raise the banks and build the secondary flood defences up to match climate change.
  • raise the banks, build the secondary flood defence and start building new defences north from Pawlett Hill towards Highbridge.

5m high and nearly 5 miles long, 100 years of digging house foundations

Sea Level Rise

Sea level rise is not expected to slow for at least 300 years making both the barrier redundant as the river banks can only be raised perhaps another metre before they overload the poor ground conditions of the Parrett Estuary. Ultimately the long term plan for Chilton Trinity and Pawlett Hams’s will be realised.

The continued conditioning of the population by the EA to passively accept surrender to the sea as the first option for non-London areas of the UK is disingenuous and defeatist and never mind its land we need to grow food on.

Way Forward

At £100M the present solution for the  Bridgwater Tidal barrier is clearly neither sustainable or affordable. A situation that needs to be laid at the door of the Government, Somerset Rivers Authority and specifically the EA and Sedgemoor District Council (SDC) who provide joint project oversight.  We need

  1. Sustainability in what we do is placed at the centre  of our plans
  2. An independent inquiry into how flood defence is being delivered in Somerset.
  3. A peer review of the BTB project  into how it has arrived where it has.

Bridgwater Tidal Barrier Cost; an unacceptable defence

The January 2018  news that the estimated cost of the Bridgwater Tidal Barrier (BTB) had reached £100M caused the BBC last week to interview stakeholders at the EA, Sedgemoor and Bridgwater Town Council. Anyone who heard the interviews and knows anything of the history of this project will be as equally concerned as Bridgwater’s Town Council. The risk regarding withdrawal of funding is real; Government will not accept being led on and neither should the ratepayer which is becoming the real story of the Bridgwater Tidal Barrier.

EA and SDC interviews.

  1. The EA chose somewhat disingenuously to blame the hike in price on the Government making a perfectly normal and responsible demand regarding cost information. Information not previously provided to the SDC ratepayer. It was clear during the public consultations (the boards are still available on the SDC website) that the selection method (river width) was flawed in ignoring the cost of the downstream works and the associated maintenance costs that went with them. Cost confusion about this project has been a problem ever since work started on developing options and presenting the options to the public. Previous written responses raised this issue in March 2016 and nothing was done to clarify the situation in subsequent public consultations.
  2.  The well known poor ground conditions of the Parrett Estuary were again blamed. Ground conditions have become a convenient hook to hang cost increases on. If the costs associated with ground conditions are being continually underestimated at such a late date there is clearly a management issue that needs to be fixed. 
  3. SDC again conflated Cameron’s “never again “statement made in 2014 with the Bridgwater Tidal Barrier. People will continue to imagine that the Bridgwater Tidal Barrier will somehow mitigate a 2014 flood when that isn’t the case.

Readers can listen to the program on BBC iPlayer for a few weeks. Move the bar along to hear the EA at 40min and SDC is around 140min

The defence of the cost is indefensible.

The reality is that neither the EA’s technical management team, those responsible for providing senior project management/Governance (EA/SDC) or the councillors providing oversight have the necessary experience for a project like this. (£29M was beyond their reach and £100M is farther still and requires experienced management).  The BTB  was always going to get away from under them as it clearly has.

As a contributor to the EFRA Future Flood Prevention report in 2016 I highlighted the issues that are deeply embedded in this project. Entitled Managing local UK infrastructure; the Client Deficit.  it highlighted the lack of  an independent adviser to stakeholders as a continuing problem with UK locally managed infrastructure projects, it is a situation repeated elsewhere and in Somerset the SRA is a particularly good example of people being responsible for delivering projects that they are not experienced or qualified to do and not being provided with the support they need. The KSD  expansion project seems to be struggling in a similar way to the BTB. Googling ones mobile phone is not a valid substitute for experience nor is having laid a patio in earlier years.

We all now understand that the Bridgwater Tidal Barrier solution (location) was driven solely by the promoted idea that “river width”  somehow equated directly to project cost;  getting the barrier as far upstream (narrowest point) was the cheapest option for the EA. it was always a flawed strategy and the cost we are now seeing is the result of that approach. It is the result of not doing work that should have been done during the options study.  The initial cost of the downstream raising of the river banks and the cost associated with the intent to continue to do so does not appear to have been fully considered in the original location decision.

Unfortunately, valuable and costly time was spent on what sort of gate we should have had rather than looking at the overall solution and there was no challenge to the 2009 B&V spread of locations. Long term costs and the EA’s rather ambiguous position regarding the long term raising of the river banks were conveniently ignored in the 2016 public consultations.  Consultations that completely ignored the principles set out in  Government guidelines on public consultations.

This situation was compounded by the obvious client project inexperience shown in the rush to engineering studies before an outline plan was agreed that always results in the cost escalation we are seeing. The sudden arrival of the secondary flood defences is something that should have been highlighted in the option studies, it may not have been needed at sites farther downstream and was not shown in the early public consultations. After 30 years of managing the design process on much larger projects than the BTB starting a project without a real plan is always a trap waiting for the unwary. Sadly, as a result of the BTB execution strategy what we now have is less normal project delivery and more an episode of Grand Designs.  At least the consultants should avoid any blame.

What was striking in last week’s radio interview was the lack of any new arguments after all the work that has apparently been done to support the scheme in its present form. What is equally impressive is that both the EA and SDC imagine that Bridgwater will not want to grow beyond the line of the barrier over the next 100 years or that a critical piece of infrastructure should be located so close to the town. Shouldn’t someone have asked how big will Bridgwater be in 100 years? The whole BTB project appears to have now deteriorated to the justification of an original poor decision. It is most disappointing.

The information the ratepayer has seen to date raises questions of transparency or competency neither of which seems to have been achieved or available to any degree. 

Ratepayers should not be paying for all the people involved in the BTB project and the broader Somerset Flooding issues to be learning on the job which seems to be the case.

Its well past the time that the Bridgwater Tidal Barrier including its location is independently reviewed before it is presented to the ratepayer one last time.  Its time we considered moving the Bridgwater Tidal Barrier downstream to Combwich.

The questions of

  • transparency with regard to cost and economic impact.
  • management team  competency
  • oversight competency and relevant experience 
  • the approved barrier location
  • what happens at the end of the 100 year design life; Bridgwater Tidal Barrier 2?

clearly needs to be looked at as the information previously provided to the public and one assumes our councillors did not reach the standards we should expect and was wrong.

Projects do not suddenly almost double in price in 15 months without good reason. The defence of the cost increase presented in the interviews was as unacceptable as the scheme itself has now become.

Severn Estuary Forum 2017

The Severn Estuary Forum met for its annual meeting 2017 in Bridgwater, Somerset on the 5th October following hard on the heels of Question Time and the Antiques Road Show at the McMillian Theatre.

An event to see people working together to resolve climate change, flood risk and wildlife preservation it was not.

Richard Hickmet the High Sheriff of Somerset opened proceedings.

The day was split into three sessions and some notes on the highlights follow.

Energy and Climate Change

Session Chair SDC councillor Ann Fraser MBE introduced the session noting the increased trade (marine aggregates) going through Dunball now rising to 70,000T per year as a reflection of increasing economic trade. Fortunately, Ross Edwards in his following update on Hinkley Point C (HPC) noted that their aggregates jetty being built as part of the enabling works was still underway. The real reason for Dunball’s growth was more to do with HPC immediate need rather than some wider reason. The irony of the councillors assumptive claim was not lost.

Ross Edwards (EDF) was able to explain, whilst maintaining a serious face, the extreme lengths that EDF were going to protect the beach from the small feet of a jack up barge and a few discreet foundations. Yet another large corporate organisation feeling the need to succumb to the irrational demands of the modern environmentalist. He also noted that EDF had spent £20M on road improvements as part of the HPC project enabling works.

Dr Judith Wolf of the National Oceanography Centre in Liverpool provided a fascinating talk that actually dealt with the session subject. The moderating impact of the edge of the continental shelf in dissipating energy should make us all worry a little less about that large piece of a volcano that threatens to slide into the sea in the Canaries at La Palma causing a tsunami. The great flood of 1607 also got a brief note and it was not a tsunami.

What was more important was Dr Wolf’s comments on global warming and the best scenario of sea level rise being 0.5m and the worst at nearly  2.0m. Dr Wolf confirmed they really don’t know the figure as no one knows how the melting polar ice caps will impact on the world. It was received with little or no comment. 2.0m is around twice the figure that the EA is using for the Bridgwater Tidal Barrier (BTB).

Planning Governance & Flood Risk

Andy Hohl (EA) project manager of the Bridgwater Tidal Barrier project explained the mechanism of the floodgates but avoided the mechanism of the planned flood defence system.  A diagram was shown showing the planned flooding of Chilton Trinity and Pawlett Ham’s when there is coincident high tides and storm surges. It is an event that will increase in intensity and frequency as sea levels rise and after a few events will have poisoned the land.

River Parrett at Chilton Trinity and Pawlett Hams; EA flood model Bridgwater Tidal Barrier 5th October 2017; How the River Parrett will increasingly flood the Levels

The EA missed the opportunity to explain why a tidal barrier is to be built in Bridgwater rather than the conventional locations at the mouth of rivers such as at Newcastle and Barking.

Mr Hohl was asked what comes after rising sea levels makes the Bridgwater Tidal Barrier ( gate and river banks) ineffective in protecting the area from the sea. Apart from some irrelevant comments about things being done today, there was no answer about tomorrow. Tomorrow, if Dr Wolf is correct, will be only 50 and not 100 years away before a replacement solution is needed.

Wessex Water’s Lucy George gave an interesting talk on the construction of the new sewers being built around Bridgwater. Clever engineering in bad ground.

Protected Sites and Species
Alys Lavers the WWT manager at Steart gave an update on the last 3 years entitled Climate Change, Flood Risk and Community Action. It has obviously become a go to place for students studying for degrees and PHD’s. Even some elver’s have apparently decided it’s a great place deciding that the swim to Oathe and the freshwater rivers of the Tone, Yeo, Parrett and beyond was simply not worth the effort and turned right into the Steart reserve. Whether that was in the EIA and is safer than getting past the locals elvering is no doubt a study in itself. However a look at the IDB asset map apparently showing every route to freshwater blocked by a clyce  does not paint a promising future for the lost elvers.

Ms Laver was also remarkably candid about Steart. That there would be no facilities built there apart from the existing toilets. No chance of a place to shelter from the elements and have a cup of tea. Little chance then that Steart will deliver the promised economic contribution when planning permission was sought by the EA. Someone in the audience from Burnham on Sea said it was difficult to find and Ms Laver explained that the lack of signposting was deliberate. Apparently keeping the number of visitors down was done for the benefit of the locals.

What was apparent to many in the audience was that WWT Steart is really only interested in the right sort of visitor; academia and other suitable people. The ordinary taxpayers who paid for Steart from their taxes (that is where the EA get its money from) most definitely not welcome.

Rob Shore WWT, session chairman and coordinator of the Severn Vision introduced the document that was first published in January 2017. What is interesting is the ambition of this recent document. A saltmarsh from Dunball to Highbridge. The proposal outlined in this document is clearly in line with the EA’s and SDC’s current strategies set out in the Shoreline Management Plan and Parrett Estuary Flood Strategy.

The map below was generated from the Severn Vision interactive map. If you live around the Severn Estuary its worth checking out the aspirations of the various wildlife organisations.

Areas of Potential Saltmarsh

One cannot help but feel that the EA and various wildlife organisations including WWT  have the ambition to turn the coastal part of Somerset into a wildlife theme park.   Trading off the land in Somerset for planning gain elsewhere such the Bristol Ports deal where Bristol gets the economic benefit and people in Somerset beyond made to feel to feel uncomfortable in their own countryside is unacceptable. Climate change should not be used as  little more than a Trojan Horse by organisations with an overblown sense of morality and entitlement.

A question on the morality of an island that cannot feed itself flooding food producing farmland to create saltmarsh was quickly pushed to one side.

Finally a question about mitigating the noise from exploding old military ordnance being found as part of the HPC outfall construction work. Ordnance, when located, is subsequently blown up by the Navy’s bomb disposal team; it did not find someone willing and able to answer it.

Observations

What was quite clear was climate change and rising sea level is really only a device and agenda for wildlife organisations to pursue the expansion of wildlife habitat.

There was no big picture presented,  no key numbers and no one to provide context as to how the wildlife of the Severn Estuary, ordinary people and business might co-exist. Key local councillors present on all the flood committees, Wessex, the drainage boards and the SRA were with the exception of Ann Fraser notable by their absence. Perhaps there were no expenses paid for attendance. Councillor Fraser it was noted in the Speaker Summaries although not an engineer had been “instrumental in leading a technical review of the flood risk in Bridgwater”. The Somerset Rivers Authority is no better with regard to engineering. There is a disturbing and dangerous precedent of non-qualified people in influential positions shaping Somerset’s flood and climate change plans. Google and mobile phones do not make an expert. 

There is simply no leadership or vision when we should be looking forward not 100  years but perhaps 2 to 300 years. Sea level rise is not stopping and schemes such as the Bridgwater Tidal Barrier that just look forward 100 years and stop with no apparent reason defy reason and responsibility; what is the plan afterwards? there isnt one.

Perhaps worst of all for an event sponsored by my own institution, the Institution of Civil Engineers, there were no engineers representing the many companies making money from climate change. Engineer’s created the landscape we have and the current generation should be leading process of planning for our future but seem to have abdicated their interest or responsibility in shaping the land bordering the Severn Estuary.

Somerset and the other counties of England and Wales that border the Severn Estuary need to have a serious conversation and take control of climate change issue at a regional level. The situation needs a champion with authority and knowledge.

Bridgwater Tidal Barrier Drop in Session 10th July 2017

On the 10th of July at Bridgwater Town Hall (2-7pm) the EA and SDC will reveal the final form of their scheme for the Bridgwater Tidal Barrier. Its construction will shape the town for the next two hundred years. It is planned to be commissioned in 2024 and designed to operate for 100 years. The operational date is a political one rather than climate driven and unlike most similar structures it will be located within the town rather than at the mouth of the river.  Mitigation of a similar fluvial flood event to 2014 is not part of the barrier’s function.

People have been focused on the barrier yet the river banks are the important bit; what happens to them will decide how radically our existing landscape will change and have far greater impact than a set of gates. The downstream river banks are being maintained in accordance with the FCERM Strategy (the national flood and coastal erosion risk management strategy for England).Individual polices are detailed in the local 2010 Shoreline Management Plan covering the next 20, 50 and 100 years.

For the Parrett those policies say that within the operational life of the barrier “The long term vision is for a more naturally functioning estuary, through construction of set-back defences under a policy of managed realignment.” Land is being returned to the tidal zone.

EA maps produced in 2010 show how that will be achieved at Pawlett Hams and Chilton Trinity. The recently released BTB secondary flood defence plan and residual flood risk maps show the long term policies are being put in place. Only the river banks close to Combwich and Chilton Trinity housing will continue to be raised. Farmland will ultimately be flooded and lost as the majority of the river banks will cease to be raised to match climate change. Steart Peninsula’s habitat will in due course be extended to Dunball and Chilton Trinity.

The present scheme means that the opportunity to increase the conveyance capacity of the Parrett capacity by moving a future replacement barrier downstream is lost. Taunton Deane and South Somerset may have to build fluvial storage on their land in the future. Opportunities for a cost effective bypass will be lost to the detriment of Bridgwater and West Somerset. As a naturally occurring event Somerset land owners will not receive compensation. Bridgwater will pay around £20m in lost land values towards the present scheme. A major economic impact on Somerset as a whole is just being ignored.

It is simply not true or credible that the BTB can somehow be divorced from the EA’s longer plan for the Parrett Estuary; a plan prepared in 2010 predating the 2014 flooding of the Somerset Levels.

The Bridgwater Tidal barrier in its present form passed its sell by date in 2014 when fluvial flooding moved from management on the Levels to flooding within our homes. Even today people still imagine that the Bridgwater Tidal Barrier is somehow part of the scheme to mitigate the 2014 flood, it could be but it isn’t. The Levels’ will still flood as they did in 2014 if we get similar weather conditions.

With little information in the public domain including the option studies that supported the original 7 location and the shorter list of 4 it is not unreasonable that this scheme has many questions of transparency.  it  is unacceptable that important and relevant information is not available to the public ahead of the final consultation on the 10th of July. That flood maps produced in September 2016 have only just been published giving people little time to understand the implications of what is planned.

If the FCERM Strategy and Parrett Estuary Flood Management Strategy are executed in their present form 1000’s of acres of agricultural land will be lost to food production. Is it morally right that the UK which cannot feed itself should export even more of its food production overseas and possibly deny food to others? This lack of responsibility on our part will no doubt be further compounded when our overseas aid budget has to be used to relieve a famine we as a nation knowingly or perhaps worse unknowingly contributed to.

To reach this situation there is a clear lack of leadership, vision, scrutiny and oversight by those organisations and people charged with delivering the plan and the infrastructure for Somerset. Neither SDC nor the SRA has any engineering or qualified staff able to lead on flooding and  has chosen not to bring in people that could. There is also a clear engineering  deficit in the delivery of Somerset’s flood defences.

People should go along to the consultation and ask

  1. Is turning the River Parrett back 500 to 1000 years and extending the Steart Peninsula wildlife habitat to Dunball whilst constraining economic development really what Bridgwater and wider Somerset need?
  2. Why wasn’t a barrier considered at Combwich and extending to Pawlett Hill that would protect the whole area. Arguments that we might impinge on the edge of the SSI is not an argument for not even looking at the possibility.
  3. Why does the barrier only do TIDAL and not  FLUVIAL (2014 rainfall) with equal importance?
  4. What is the extra cost of building a barrier with a bridge on it?

 

Steve Trowbridge CEng MICE MIStructE

 

 

Somerset Flooding- A silver lining lost

A year or so ago  when Sedgemoor District Council (SDC) and the Environment Agency started work on  the Bridgwater Tidal Barrier  (BTB) scheme they jointly decided not to spend money on an economic impact assessment.

As  a result of that decision there is now no way for councillors, ratepayers and business to measure and benchmark the wider commercial and economic impacts of BTB project.  The project  is now simply valued and measured by government rules. This is especially important for those ratepayers and the HoW LEP who will directly pay for a proportion of this scheme.  For Somerset’s councillors there is no visibility of  the potential direct local (Somerset wide) benefit. With a preferred location agreed and the full details still yet to be seen or shown to the public it is difficult to see  how the Bridgwater Tidal Barrier  can be proceeding as it is.

There is a need to scrutinise the  EA’s proposed Bridgwater Tidal Barrier and its management of the delivery of the scheme. There urgently needs to be some form of independent peer review to support the decisions of councillors and EA employees who do not have suitable engineering qualifications and experience. No private company would do this.

The  River Parrett catchment  and its capacity affects much of South and Central Somerset; almost every town is on one of its tributaries. The wider opportunity that Somerset’s flood defence expenditure presents has to date been largely ignored and is in danger of being squandered. Sensible promises made in 2014 have been quietly allowed to disappear.

If you live within the Parrett Catchment or  in West Somerset this article will be worth reading for economic reasons alone.

River Parrett Catchment Area

By 2024 nearly £100M will have been spent on flood related work within Somerset and the majority of the money focused to the north and north west of Bridgwater. The EA’s  managed realignment at Steart Peninsula and the adjacent Bristol Ports property deal for it proposed container port that is of no economic benefit to Somerset sees nearly 3000 acres of farmland removed from the the local economy.

However

  • The Levels will still flood and as they did in 2014; they will simply drain more quickly.
  • A flood defence system will have been built that only works for sea water (tidal) and that will probably have to be replaced because it will not be viable to extend its design  life because of the ground conditions along the river banks.
  • The expansion of Bridgwater over the next 100 years ignored.
  • The rather novel concept of putting a tidal flood barrier 5 miles upstream of the mouth of  the River Parrett and into the town implemented.
  • An additional 2,000 acres of productive agricultural land will be in the process of being lost  to agricultural bringing the total of land lost to the local economy to 5,000 acres including Steart Peninsular and the Bristol Ports land deal.
  • There will be no bridge over the Parrett although the myth that you cannot easily have both on one structure will have been discredited albeit too late.
  • No beneficial integration with a future Bridgwater bypass considered or provided.
  • An important relationships  between the capacity of the KSD/Sowy expansion and the impact of the location of the BTB never mentioned or costed.
  • The planned loss of Pawlett Hams to the sea lying hidden in the Parrett Estuary Flood Risk Management Strategy.

Perhaps the most unfortunate decision to date  was naming  the barrier/barrage the Bridgwater Tidal Barrier and sending mixed messages as to its purpose. That single act has reduced interest and scrutiny both in Sedgemoor and further afield to almost nothing. Only 180 people came to a public consultation in September 2016.

The  introduction on the SDC barrier website reproduced below implies on the last line that it “could play a critical role in reducing flood risk” (tidal) and not the fluvial flow it started talking abut; they are not the same thing but did meet once in 2014. Two different things have been conflated  into one message.

The barrier is not designed to mitigate a another 2014 flood

with regard to fluvial (rainfall) flooding

  • Would it now have had an impact on another 2014 flood?          NO
  • Could it be made to have an impact on another 2014 Flood       YES.

Somerset’s councils seem to have no interest in this scheme yet they should because

Somerset County Council (SCC)

Despite having the SRA under its wing and councillors jointly at County and District level there is little in the way of a long term vision that can be see being developed.

A shorter more strategic tidal scheme closing off the South Somerset Levels from the sea  by closing the short gap between the hills from Combwich to Pawlett Hill has not been considered.

Such a scheme would

  • Secure the south Somerset Levels from the sea.
  • Improve the fluvial capacity of the River  Parrett to the benefit of Taunton Deane and South Somerset as well as Sedgemoor.
  • Provide a bypass and improved  road link to West Somerset using EDF’s extended Cannington Bypass.

 

West Somerset

West Somerset’s economic development is constrained by two roads (A39 & A358) and the need to navigate across either Bridgwater (A39) and Taunton (A358)  road systems to get to the M5. With little or no options and no Government money available as part of its road budget it is an area of Somerset where the wealth and opportunity of its population is always constrained and likely to continue. No doubt why it loses industry and income.

It is difficult to understand why West Somerset isn’t trying to improve its economic link to the M5 motorway and via the A39  to Frome, Wells, Shepton Mallet, Street, Glastonbury and Yeovil.

Constructing the Bridgwater Tidal Barrier at Combwich with a road bridge taking advantage of the recently constructed EDF extension to the Cannington Bypass would provide a significant economic benefit to West Somerset.

Taunton Deane & South Somerset

Both local authorities rely on their respective tributaries Rivers Isle, Cary and Tone to convey surface water to the River Parrett and onwards to the sea. No amount of SUDs, storage on the Levels or slow the flow is going to change the fact that you can only get so much fluvial flood water out through the River Parrett. That constraint will ultimately have to be faced by limiting economic development  The opportunity has not been taken to leverage  the long term benefits for the two districts by moving the  barrier downstream.

The reason to relocate the  selected  Bridgwater Tidal Barrier site downstream is that its preferred location does almost nothing to improve the conveyance of surface water to the sea. Where it is now proposed above the King Sedgemoor Drain outfall means that the full benefit of the KSD/Sowy expansion cannot be achieved or the capacity of the River Parrett optimised. Capacity that would benefit largely Taunton Deane and South Somerset. That scheme is being paid for by everyone and is simply not as good value for money as it could be. Rising sea and tide levels will reduce the time the KSD sluices can discharge. That situation will invariably negatively impact both districts by limiting how much water can go in to the system at their end.

It is therefore surprising that neither council has been pushing the barrier downstream where it could be used to increase conveyance in the same way as the Thames Barrier does. Increasing the overall capacity of the system when the Levels again flood is the priority and an opportunity not to missed offers one less obstruction to those two districts economic development.

Sedgemoor District Council (SDC)

South Somerset Levels

Sedgemoor opted to support a 15Km long scheme that cannot be extended (raised) as sea levels rise. Somewhere a bigger one will be required. Its consultants never looked at what would be the best scheme for Somerset or indeed wider Bridgwater. It is just what would be the cheapest for the EA whilst the SRA and SDC looked on. A location for the barrier where a bridge cannot be added to it is hardly planning for the future but it does ensure the ratepayer does not get value for money.

North Somerset Levels

Defending the North Somerset Levels could be achieved by the construction a new barrier from the Polden Hills to end of the Mendips (Brean Down). Such an undertaking could be easily done providing undeveloped land is identified. We could create a second line of defence over the next 30 years letting Somerset contractors run recycling operations allowing trains to bring in recycled materials to form a continuous flood defence. Its time managed retreat was abandoned.

What is disappointing is that with the SDC Local Plan under development there is no land being reserved for future improvements to the flood defences. The organised surrender of Somerset’s hard won land is being orchestrated by the EA under its Managed Realignment process and no one is challenging it. Everyone in Somerset should be interested in what is being done along the coast for safety and economic reasons. There is simply no plan.

Heart of the South West LEP

The Heart of the West LEP with its support of the BTB a project will ultimately damage local businesses based in most districts (£16-20M of lost land values) whilst in a current study is looking at improving rural businesses . The LEP is an organisation facing both ways to the detriment of everyone.

Somerset needs some joined up thinking and understand the very negative implications of some of Somerset’s flood defence scheme.Only when its built and its limits apparent will people say “if only”. 

The Options looked at by the EA lacked any sort of imagination or offered a long term solution; were simply variations on a theme and ignored the nearby topography that offered other options for the Bridgwater Tidal Barrier

It is unacceptable that better engineering options were not  identified and presented to councillors; ultimately it should be the ratepayers decision to go for a better solution if they want to. The EA should not presume as it has in this case.

On the 14th July  starting at 10.00 am  the first opportunity to do something takes place when the SRA scrutiny committee meets in open session at Somerset County Hall, TA1 4DY. 

Some Questions to Ask

  • Why is the Bridgwater Tidal Barrier not also designed to help to mitigate the effects of a similar flood to 2014?
  • What is the replacement plan for the Bridgwater Tidal Barrier?
  • What is the cost of a scheme with a bridge ?
  • Should we only be spending our money on such a limited scheme?
  • Why wasn’t Combwich and the resulting shorter flood defence system that protects a larger area than the current scheme considered by the EA?
  • Does the extension of the Cannington bypass towards Combwich necessitate the reassessment of the present scheme?
  • Should Somerset County Council be looking at a more holistic scheme for Somerset?
  • Should SCC commission a county wide economic assessment of what an alternative barrier scheme might deliver?
  • Do we need the EA or should the SRA be expanded to become a delivery focused organisation and the EA limited to a statutory consultee ?
  • Is the role of environmental charities in developing and influencing flood policy beneficial and do they have a conflict of interest?
  • Why after 3 years since the flood and 8 years since the barrier identified as the preferred solution is there almost no information about the scheme on the http://www.sedgemoor.gov.uk/bridgwaterbarrier website?

The EA plan another consultation on the full scheme later in 2017. Councillors of all Somerset’s districts  might like to look at the economic impact of this scheme (BTB) on their own areas and perhaps county might look at the bigger picture.

An unintended consequence is only the failure to adequately consider a decision before it was made.