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Broad minded thinking

Flooding & coastal Broadlands

The Environment Agency is using the private sector to secure a healthy future for the Norfolk Broads. Nina Lovelace reports.

The Norfolk Broads in summer buzz with activity. Full of canal boats, riverside pubs bursting with tourists and a plethora of rare and interesting wildlife, they are a place many love to holiday. And so they should. The Broads are a designated national park full of protected habitats - the jewel in East Anglia's crown.

This jewel only remains sparkling, however, thanks to the dedication of environmental and wildlife bodies. None works harder than the Environment Agency, which manages the 240km of earth embankments that control the flow of water along the rivers and canals tracing through the low-lying region.

Without floodbanks to protect low-lying freshwater marshland from the saltier estuarine water of the broads, many of the delicate habitats would have been lost. The sea would also have inundated agricultural land and blighted properties.

In recent years, however, the Agency has realised that time has taken a toll on the floodbanks, many of which are hundreds of years old. Instead of starting a maintenance regime using traditional routes of procurement, the Agency decided in 1999 to carry out the work using the private finance initiative.

In May 2001 Broadlands Environmental Services (BESL), a joint venture between contractor Nuttall and consultant Halcrow, tendered and won the £100M PFI contract for care of 30,000ha of the Broads, located around three main rivers - the Bure, Yare and the Waveney.

BESL's task now is to maintain and upgrade defences in the 40 different Broadlands regions, build new defences for 500 previously undefended properties, and provide 24 hour emergency flood response for the whole region for the next 20 years.

BESL director James Roundtree sets out the challenges ahead: 'Under this contract we have 12 years to improve defences in the Broadlands, and then eight years to maintain them. And at the end, we have to hand back all the flood defences with an average working life of a further 7-10 years.'

Environment Agency project manager Paul Mitchelmore says the decision to use the private sector originated in the mid 1990s. Many existing earth embankments were nearing the end of their useful lives, and previous patching exercises were not delivering the standards the Agency wanted. A long-term plan was needed, and one that could be delivered by experts with new resources and ideas.

Bringing the private sector in was seen as the best way of achieving this: 'Having a longterm contract encourages the private sector to invest in the region, but also enables the team to build up long-term knowledge of the region and relationships with us and local stakeholders, ' says Mitchelmore.

The Agency is hoping the areawide contract will help BESL achieve economies of scale, and the team is given an incentive to innovate by having a target cost for each of the 40 regions. If a solution can be delivered for less, BESL receives a share of the financial gain.

Communication between client, consultant and contractor has also been helped by the team's decision to co-locate in a single office in Norwich, with East Anglian research body CSERGE. CSERGE is on board to help consult with 16,000 stakeholders, including farmers, wildlife experts and canal boat businesses, and to help with environmental assessments.

Plans are still in the early stages, as the project has only just kicked off, says Roundtree.

Detailed flood modelling based on 1995 climate change assumptions is being carried out for each Broadlands region, together with condition studies of existing floodbanks and a tranche of environmental assessments.

Each region throws up different challenges - for example protecting particular habitats.

But the team expects to find some common problems, including maintaining easy navigation.

Roundtree explains that they expect to carry out considerable work on the floodbanks. 'Some of them date back to the Middle Ages - they don't even have a clay core, ' he says. 'What's more, most of the older ones are very steep sided but narrow. As a result, they are more likely to have their tops ripped off in the event of a breach.'

Many of the floodbanks will be raised and bolstered from behind by addition of extra material. However, this will only happen if the floodbank is already protected from erosion by a strip of land between the floodbank and river.

If the flood bank is right up against the river it is likely a new floodbank will be built behind it, and the original demolished to provide a defensive foreshore or 'rond'.

Another challenge will be to tackle the many floodbanks fronted with sheet piling, originally added to protect them from erosion, adds Roundtree. 'A lot are in a poor state of repair.'

Piles are at risk of failing, falling into the river and taking the floodbank with them.

Roundtree is quick to mention that piles will not simply be replaced. 'The Agency has been concerned that sheet piling would eventually turn the Broadlands into a big canal. So we want to get back to a much more sustainable approach.' Instead, BESL is aiming to introduce more natural and less obtrusive methods to protect ronds and floodbanks, and to stop tidal flows and burrowing vermin from undermining soil slopes.

'We are already trialling gabions, asphalt matting, timber piles, reed bundles, coir bundles and plastic piles, ' says BESL technical manager Kevin Marsh. 'Innovation is very important to us on this project, ' adds Mitchelmore.

The team has also been investing heavily in detailed GIS maps of the whole region, overlaying Ordnance Survey maps with aerial photographs, embankment condition surveys and on-site photographs - no small task for 30,000ha. 'We couldn't make this type of investment unless we had a long-term interest, ' says Marsh.

Meanwhile, emergency work continues on the weakest floodbanks and critical projects that can not wait. Construction work is drawing to a close at the canalside village of Reedham, where for the first time a new floodwall will protect properties from rising waters.

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