Shoring up the Sow

Stafford might not be on everyone's tourist trail, but this doesn't mean the town, made popular in Victorian times, is not an attractive spot to visit. When visitors emerge from the railway station, they face the appropriately named Victoria Park and should they choose to get to the town centre on foot, they will cross a footbridge over the River Sow and have a bird's eye view of flood defence work currently being carried out by Jackson Civil Engineering. The reason for this construction activity is the serious flooding that occurred in Stafford in November 2000. This wasn't the only occasion. The Victorian town has a history of flooding with particularly bad instances occurring in 1946, 1977 and 1981.According to the Environment Agency (EA), an asset survey carried out in 1994 concluded problems were developing at the river edge in Victoria Park. This was attributed to poor ground conditions in Stafford and the authorities decided that the existing piling was in need of repair.As well as repairing the retaining walls and flood defence wall protecting the town, the project's aim is to upgrade the town's flood defences from a 1 in 25 year standard (see box for flood classification) to a 1 in 100 year standard.The project is divided into two phases with the first phase carried out between April and October 2002. The second phase is scheduled to follow a similar time frame this year. JCE is engaged on a 3.6m contract to build new retaining walls to replace the existing bank structures and to install 2,000 sheet piles along part of the River Sow which flows through Stafford. According to Paul Watson, JCE's project manager, an 1,800m stretch of the riverbank is being strengthened with the flood defence wall covering a length of 350m.The working area is at a premium for JCE operatives as the riverbank allows little room for manoeuvrability. "We have to clear areas immediately adjacent to the river so that we can sheet pile," explains Watson.Due to the space constraints, not helped by the canopy of trees along the riverbank, JCE opted for a side-grip sheet piler.With its side grip, the sheet piler can handle piles up to 13m-long and thanks to an on-board computer that controls the verticality of the pile, it also reduces the need for a piling guide.Because the ground is so soft, Watson says they did not experience a period of high vibration.As one of the first full contracts to operate under the EA's National Contractors Framework Agreement, what are Watson's first impressions?His response is positive."There is more interface between the designer, EA and ourselves," he says. "It is a shared experience and if there are problems in the offing, they are solved early on."Watson also points to the fact that while there is less bureaucracy, there is a mechanism within the framework that allows team members to continually evaluate the way the system works."It is being looked at closely by the people within the framework and where things can be improved, there is the opportunity to do so. Frameworks are good from a contractor's point of view as you can plan better and more effectively."This is a sentiment echoed by James Mallender, EA's project manager."There are already great examples on site of the new framework principles being adopted showing team decisions on the supply chain. Working closely together with JCE and EA consultants, Atkins, means that as a unit we can be flexible, reacting quickly to implement solutions for the day-to-day challenges that arise on site."An example of incorporating clever ideas at an early stage was Atkins' proposal to install a reinforced earth section on the side of the riverbank. Designed to be a storage area for the water between the river and the in situ concrete flood defence wall in the event that the river water levels rise, the reinforced earth section has a depth capacity of 600mm."The cost of installing piles was more than the procedure to reinforce earth," recalls Watson. "It is a clever design and only works in a location like this."Maintaining a high standard on the project is one of the team's key objectives and Jim Chaplin, JCE's key client/services director, says the contractor has a big incentive to perform."Our performance is linked in with the EA's objectives. These include environmental issues as well as health and safety," says Chaplin.While he is clearly delighted that JCE has become an EA framework contractor, he is under no illusion as to what working in such an agreement entails."To get to the true benefits, contractors must be involved at a much earlier stage. Traditionally, we only get involved when the project has already been designed so it is almost too late for us to contribute much. Being part of a framework agreement enables us to be involved as early as the feasibility stage."Does that mean JCE can afford to be complacent about the agreement being renewed after the initial five-year period is over?"There is absolutely no certainty it will continue past five years," says Chaplin emphatically. "It is a process of continuous development. Five years is no time at all and it is unlikely that any significant work will be achieved in one year where we will only see a shallow learning curve. We will only see major benefits of working within the framework agreement in four to five years' time."According to the EA's Mallender, the framework team's performance is judged on a quarterly basis."We hold an open meeting with the consultant and contractor and it is an occasion from which we all learn a lot."Another body working closely with JCE is Staffordshire Wildlife Trust."A wildlife corridor is being created on site that will allow small mammals, such as water voles to move along the river, as well as provide refuges for fish and other water creatures," explains Watson.Besides fish and water creatures, other local residents include interested passers-by who stop to watch the work and -- given the opportunity - to have a chat with a JCE operative."There is no restriction on the team speaking to town residents," says Watson. "The company actively encourages operatives to communicate with the locals. After all, if you're telling them the truth, you have got nothing to hide."