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Volume 714: debated on Tuesday 10 November 2009


Asked by

To ask Her Majesty's Government further to the Written Answer by Lord Adonis on 28 October (WA 147), on the advice of which other Government agency the Highways Agency decided to build two bridges for bats over the Dobwalls Bypass in Cornwall; what consideration was given to the adequacy of a single bridge; who drew up the specification for the bridges; and which contractor constructed the bridges. [HL6159]

The Highways Agency is legally bound to protect endangered species such as bats. Mitigation of the severance of three of their main flight lines formed part of the commitments we made at public inquiry in support of European protected species legislative requirements to enable the bypass project to progress, especially since surveys found 12 of the 14 native species of bat in the area.

The Highways Agency sought advice from English Nature (now Natural England), a statutory consultee. They indicated that measures would be required to mitigate the severance of three of the most important bat commuting routes by the then proposed Dobwalls Bypass.

These three commuting routes are some distance apart, and highlighted the need to provide separate mitigation measures for each route. The measures comprised two artificial bat crossing structures plus a raised parapet modification to the new Havett Road overbridge crossing.

The contractor for the bypass, Interserve Project Services Ltd, constructed the bat bridges. Interserve’s design consultant, Parsons Brinckerhoff and environmental sub-consultant Ecological Planning and Research Ltd drew up the specification for them with advice from Natural England.

Asked by

To ask Her Majesty's Government over which roads the Highways Agency has constructed bridges for bats in each of the past five years; and what was the cost of each such bridge. [HL6160]

The Highways Agency has constructed structures that enable bats to cross roads at four locations. The table below highlights the locations, length and costs of these structures.

Bat structures designed and constructed between 2004 and 2009

Scheme Name

Road Number

Road opened

Approx Length of Structure (metres)

Single or Dual Carriageway

Cutting/Embankment/At Grade

Approx Construction Cost of Structure

Dobwalls 2 Structures


June 2008

Structure 1—59.47m Structure 2—70m


At Grade/In Cutting


Haydon Bridge


April 2009

19.5m between support posts


In cutting


High and Low Newton


April 2008

33m span between timber supporting posts


In cutting


Parton to Lillyhall


Dec 2008

34m span between supporting steel structures


On embankment


Asked by

To ask Her Majesty's Government whether, under the legal obligation to protect endangered species, there is any limit to the expenditure that the Highways Agency is required to undertake to provide bridges for bats over new roads; and whether, in the event of the provision of such bridges making the construction of the road under the benefit-cost ratio standards uneconomic, they would cancel or postpone construction. [HL6161]

Mitigation works undertaken on a Highways Agency major project for bats are implemented under the Conservation (Natural Habitats, &c.) Regulations 1994.

The legislation does not place an expenditure limit on the provision of bat bridges over new roads. The costs associated with the construction of a bat bridge will vary for a variety of reasons, therefore each scheme is assessed on an individual basis.

If the cost of provision of bat bridges caused the benefit-cost ratio to drop to the point where construction of the road was uneconomic, then alternative options which meet the scheme’s objectives at a lower cost would be considered in the first instance.

If no viable options were found, it is possible that construction could be postponed or cancelled. However, this would be highly unlikely as bat bridges form a very small part of the overall scheme cost for new roads.

Asked by

To ask Her Majesty's Government whether they will review the cost to public bodies of complying with the legal obligation to protect endangered species such as bats. [HL6162]

The European Habitats Directive places member states under an obligation to ensure that species listed in annex IV to the directive are given strict legal protection; this includes species such as bats. All public bodies are also under a general legal obligation to have regard to the purpose of conserving biodiversity in the exercise of their functions by virtue of Section 40 of the Natural Environment and Rural Communities Act 2006. Measures taken to comply with these obligations can take many forms depending on the individual circumstances of the case in question. The extent of any feasible or necessary measures will very much depend on the degree of harm to the species that is foreseen.

In general, good advanced planning and design, with expert advice where appropriate, will help to minimise the costs of compliance. The requirements of the directive are no more than is necessary to maintain the populations of the species concerned at favourable conservation status. Given the extent of the variable factors, we have no plans to review the cost to public bodies of complying with these obligations.