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Are you Clear About Carbon? - Pedestrian Footbridge Case Study | January 2013 www.clearaboutcarbon.com

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Case study

Sustainable Timber Pedestrian FootbridgeQuotation to design, manufacture & install a pedestrian bridge in East Cornwall.

2Are you Clear About Carbon? - Pedestrian Footbridge Case Study | January 2013 www.clearaboutcarbon.com

Introduction

In 2011 a procurement project was launched to install a new

pedestrian bridge in Stara Community Woodland in East Cornwall.

The bridge would span approximately 11 meters of the River Lyner

and link Colquite Wood with Broad Wood. A primary supplier

was sought to design, manufacture and install the bridge using

‘in-house’ company resources. Evidence of experience of similar

projects with appropriate accreditations was required.

BackgroundThe Caradon Hill Area Heritage Project (CHAHP) is a Heritage Lottery Fund Living Landscape Partnership Project that is helping to recognise, conserve and enhance the area’s special character.

Friends of Stara Woods (the client) expressed a desire in the footbridge being constructed of sustainable materials as far as was practical and in budget.Mike Shillaber, Procurement Category Lead, Cornwall Council.

The area includes Stara Community Woodland, which is a collection of three woods: Broad, Colquite and Treovis. Documents suggest that these woods have been in existence since at least the 17th century, and probably long before that.

A small team of committed volunteers, which together are members of the ‘Friends of Stara Woods’, help to run community events as well as managing the ongoing maintenance and development of the woods. The aims of the Friends of Stara Woods are to achieve “the effective ecological and sustainable management of the woods as an arts/ environmental/ educational/ recreational resource for the area while maintaining their essential beauty and tranquillity.”

In addition to the volunteers, working parties from the Probation Service and Youth Offenders Team come to work in the beautiful woodland setting as part of their rehabilitation process. Local school groups and children visit the woodland to engage with the landscape and to develop their understanding of the environment in which they live. Community groups and volunteers come together to enjoy the woods and help with the management of the landscape or at events to celebrate their diversity.

The procurement of a new footbridge was commissioned by Cornwall Council on behalf of the Friends of Stara Woods with funding provided by the CHAHP project.

3Are you Clear About Carbon? - Pedestrian Footbridge Case Study | January 2013 www.clearaboutcarbon.com

Procurement Route Followed – Request for Quotation

SpecificationThe specification included the following aims & desired outcomes for the Project:• Toprovideapedestrianbridge spanning the River Lynher to enable persons to pass from either bank in single file.• Toprovideameansofpreventing cyclists, motorbikes or horses from being ridden across the bridge.• Toprovidearelativelylow- maintenance structure that is deemed by the landowners to be aesthetically pleasing and appropriate for the setting.

Legislative RestrictionsThe bridge must comply with restrictions and guidelines laid down by the Environment Agency for structures spanning a river, which requires that there is no obstruction to water flow. Commissioning of the contract would be dependent on Environment Agency consent based on the winning contractor’s final design and method statements.

Key details of the procurement are summarised below:

Category: Transport InfrastructureValue: £34,000Procurement Route: Request for QuotationAdvertising: Tenders in CornwallQuotations Received: 2Evaluation: Quality 70% Price 30%

General Conditions• Thesiteisanunsupervised,publiclyaccessiblelocation so due consideration should be given to the design and the choice of materials to minimise the risk and consequences of any vandalism.• Itisnotenvisagedthatvisitorswishingtousethe bridge will be particularly high in number or regular in their use.• Becausethewesternbankoftheriverisgenerally fairly wet and the intention is to leave it in its natural vegetative state, it is not considered a high priority nor necessarily appropriate to design the bridge to be DDA compliant particularly as this is liable to counteract the measures noted in ‘aims’ to prevent vehicular access.• Theeasternbankisapproximately1.5mhigherthan the western bank and it is envisaged that the bridge will be level with the higher footpath on the eastern end and an appropriate standing with ramp to ground level will need to be incorporated into the design at the western end.• Thewesternbankisliabletooccasionalfloodingwhen the water level rises in the river.• Thesiteiscurrentlyonlyaccessibletoequipment/ machinery along the eastern bank.• Contractorswillbedeemedtohavesatisfied themselves of the site ground conditions and the suitability for designed foundations and fixings.• Anytimberand/orwood-derivedproductsmust originate from either legal and sustainable or FLEGT (Forest Law Enforcement, Government and Trade) licensed or equivalent sources.

4Are you Clear About Carbon? - Pedestrian Footbridge Case Study | January 2013 www.clearaboutcarbon.com

Request for Quotation (RFQ)

Tenderers were required to respond to the

following criteria:

Experience (10% Overall Weighting):Provision of details of similar projects that the tenderer has designed and/or constructed with, wherever possible, emphasis on similar low-impact, unmanned, rural sites during the last 3 years.

Working methods (10% Overall Weighting):The site has restricted highway access and on-site environmental/ ecological considerations that preclude the use of all but the lightest plant and machinery. A method statement of proposed access, site accommodation, ground preparation, installation methods was therefore required along with details how the existing site environment would be safeguarded.

References (20% Overall Weighting)The tenderers had to provide reference details for 2 similar sized contracts which they had been awarded within the last 3 years for the provision of services and works, similar to those required for this commission.

Design (20% Overall Weighting):Provision of a working sketch drawing and/or photographs of the proposed bridge design together with load calculations and a brief explanation of the design philosophy that explains why it is appropriate for the woodland setting and how it complies with Environment Agency requirements for spanning the river. The aesthetics and deemed appropriateness of each design would be considered and adjudged by a panel from the landowners (Stara Woods Trust) and the funders (Caradon Hill Project) based on the sketch design/photographs.

Specific reference was required to the materials and components to be used, including as a minimum:• Sourceandsustainabilityofallmaterialsquoting accreditation where applicable;• Specification/gradesofcomponentsandmaterials including confirmation that they are suitable for use in this environment;• Lifeexpectancyofcomponentsandmaterialswhen incorporated in the final structure with reference to any guarantees where applicable;• Considerationofhowthebridgeisdesignedto be assembled and/or installed with the minimum environmental/ecological impact to the site.

Ongoing maintenance (10% Overall Weighting):Provision of a draft maintenance regime for the finished structure noting the periodicity and level of technical knowledge required to fulfil the safety inspection and maintenance inspection role of the installed bridge.

AwardThe winning supplier scored 78% overall scoring particularly highly in their consideration of sustainability and the environment and prior experience.