Joined Up Thinking - Part 1: The Thames

Do you remember this poster? You might if you were born before 1982 when the Greater London Council issued this warning about the dangers London faced from flooding.

Following the catastrophic damage sustained in 2005 by New Orleans during Hurricane Katrina, nobody now fails to appreciate the impact of the failure of flood defences on city regions sheltering behind them.

In our previous report on the S106 difficulties with DP World’s development at Thameshaven, we made a passing reference to proposals for a new Thames Crossing.

Options study by Parsons Brinckerhoff January 2009

This week Mark Hansford writing in the New Civil Engineer brings the story up to date, and it would appear that proposals for a new Thames Crossing are now to be integrated into plans for a new set of Thames flood defences.

Joining it All Up

The Highways Agency plans for a new Dartford Crossing could be co-developed with new Thames flood defences, the Environment Agency said this week. This is a story of joined up thinking – something, as you may have noticed we are normally prepared to beat people to death with my keyboard about. Alas, however, whilst it is a start of joining up process, the current coalition does not represent the broad collection of stakeholders necessary to maximise the benefits that could arise from this major investment. Other groups such as the DfT Rail and Air departments, Network Rail and "Blondie" – (not the iconic new wave punk group who broke up in 1982 but the Mayor of London, as he's known to some) are needed to explore all of the joined up options. At the moment this is a deal cooked up by Agencies preoccupied with roads and rivers, therefore we cannot be surprised that rail based transport links and other transport interests receive scant attention.

Now, as politicians of various political persuasions face the challenge of reducing government expenditure, rebooting the wider economy and addressing the challenges of global warming, is just the time for a broader debate on projects such as this.

This is an area that many economists regard as fogged with what they describe as "hocus pocus." It is important to remember there are two ways of reducing cost. One is to cut expenditure and cope with the loss of value that the expenditure does or would have created. The second is to maintain the level of expenditure, but to increase the value gained for the money.

In esence it is not what a thing costs that is important – it is the value you get that counts. Seeking higher value from existing expenditure requires - in most cases - a greater degree of intellectual rigor than a simple slash, burn or postpone campaign, but it is generally well worth the effort.

The International Monetary Fund (IMF) is firmly of the view that the value added of any government investment will count for a lot in the recovery of national economies. Investment in infrastructure will have far more impact than tax cuts for governments trying to boost economic growth in the face of the global recession.

The IMF’s report on the global economy was published ahead of the Group of 20 (G20) heads of government meeting at Excell in London in April. In it, the IMF estimated that the stimulus packages announced so far would probably add between 0.4 per cent and 1.3 per cent to growth this year across the world’s big economies. With global growth predicted to slow to just half a percentage point in 2009, the IMF suggested that government spending boosts and tax cuts are the only measures keeping the global economy from an outright contraction.

Of the two alternatives, the IMF's chief economist, Olivier Blanchard, believes that speeding up infrastructure projects is a better way to stimulate economies during a recession than cuts. IMF estimates of the so-called “fiscal multipliers” – the eventual effects on gross domestic product of a given tax cut or increase in government spending – showed that infrastructure investment adds between 0.5 per cent and 1.8 per cent to output per 1 per cent of GDP spent by government, whereas tax cuts of equivalent size would only add 0.3 per cent to 0.6 per cent.

Mr Blanchard said:

If people were to spend it, it would be great. The main problem is basically at this stage, we think if we put money randomly in people's pockets they're going to save most of it. They may feel good about it, but in terms of what this does to the economy it's not very good. At this stage what we need is an increase in demand so you basically want to put the money where it's going to be spent.

Mr Blanchard also said that governments should be bringing forward infrastructure projects that are scheduled to begin in several years' time:

Typically with these type of measures, is that it takes so long to actually get them going that by the time you put them in place, the recession is gone. Well we're unlucky that this time we have a long recession, a slow recovery, so even these projects can be thought about and started now.

Applying it to the Thames

The Environment Agency’s Thames Estuary 2100 (TE2100) strategy document suggests a new barrier will be needed from 2070. The study found that storm surges were not expected to dramatically increase in frequency, but it said that sea level rises and rainfall increases were likely to cause a rise in estuary water levels of between 1m and 2.7m by 2100.

In summary out of the three locations considered the Agency has identified, two are leading contenders. Whilst the Agency favours a location at Long Reach, close to the Dartford Crossing, an alternative site at Tilbury is also under consideration.  

Their four main estuary-wide objectives are:

• Improve the existing defences
• Create tidal flood storage
•  Build a new barrier at Tilbury or Long Reach
• Build a barrier with locks at Tilbury or Long Reach or convert the Thames Barrier into a barrier with locks when operational limit of closures per year is reached.

The plan is scheduled to become effective from next year. Over the first 25 years, the focus would be on maintaining and improving existing defences and safeguarding land for flood management in the future. This will cost £1.4bn.  

The plan also anticipates a £3.1bn spend on raising flood walls and reshaping the riverside between 2035 and 2069. There will also need to be a decision about the final 30 years of the century. From 2070 onwards an estimated £4.2bn is expected to be spent on the frontrunner options of either maintaining and improving existing flood defences or building a new barrier at Long Reach.

Both sites are also being eyed up by the Highways Agency as locations for a new Thames crossing, as the Highways Agency acknowledges the need for a new road link to relieve congestion on the existing Dartford Crossing. The Environment Agency head of flood risk strategy David Rooke said that he would be interested in discussing options for a dual purpose crossing.  “The plan for a new Dartford crossing does open up all sorts of possibilities,” he said. 

Exploring Other Options

The Environment Agency strategy is based upon a two year £275,000 Agency-commissioned study of the impact of climate change on the Thames Estuary. done by Parsons Brinckefhoff , an American project management company specialsing in mega projects

A third option for a barrier based on the Isle of Sheppey has also been considered and all but discarded. The Department for Environment Food & Rural Affairs and the Department for Communities & Local Government received proposals in 2006 from architect Sir Terry Farrell to build a barrage linked to Thames Estuary islands. This would involve a 9km flood barrage across the mouth of the Thames Estuary from Southend to Sheerness capable of protecting the Thames Gateway development area from a 1:200 year storm surge. 

Farrell’s proposal, drawn up in detail by consultant Scott Wilson, was be topped by a cable stayed road and rail bridge to create a transport link between north Kent and the east of England. Three artificial islands behind the barrage were to be developed for housing and leisure and the money raised could help pay for the project. In many ways, this proposal was closer to current Dutch thinking for whom sea defences are part of the national psyche. The Dutch tend to be bolder both in addressing the problems of rises in sea level and increasing fluvial run off.

In addition to recognising the boldness of the Dutch vision, it is worth reflecting on their determination to make the skills they acquire whilst building their next generation flood defences a readily a marketable set of skills that will face significant demand in facing what is the global challenge of global warming.

Both Mr Rooke and Parsons Brinckerhoff tended to be cool on the need for Farrell’s barrage, claiming that the Thames Gateway is well defended: “The Gateway area is aff orded one of the highest levels of protection in the UK. Clearly we want to maintain that going forward.” Alternative projects based on artificial islands near the Isle of Sheppey are however now under consideration.  

Douglas Okervee is the former Chairman of Crossrail and was involved in the construction of Hong Kong’s replacement airport. He is investigating of behalf of the Mayor the feasibility of building an island airport in the Thames Estuary with above or below ground road and rail links to Essex and Kent. This would be located in shallow water just north of the Isle of Sheppey. The proposal would see an artificial island created about two miles off the coast of Sheerness with capacity for up to six runways and with connections to both London and the Continent via the high-speed Channel Tunnel Rail Link.  Whether the project is practical or not is an issue currently being debated, but it is something that is worth exploring in more detail nonetheless.

To be continued