The council is responsible for over 140 of the borough's bridges, culverts and subways, as well as many of the retaining walls and footbridges which lie on public highways, rights of way or dismantled railways and are used as footpaths.
The borough's bridges have recently been assessed as able to carry the largest standard loads. This involved calculating the carrying capacity of 115 bridges and 25 retaining walls.
Vehicles which weigh more than the 40/44 tonne E.C. standard for Heavy Goods Vehicles (HGVs) are regarded as abnormal loads and these loads make many journeys throughout the Wigan area. They usually consist of mobile cranes or low loaders carrying earth moving equipment, boilers etc. and can weigh up to 260 tonnes. Along the routes used by these loads, the structures which support the highway have to be assessed to check that they are capable of carrying them.
The corresponding programmes for Railtrack and British Waterways bridges in the borough is being monitored by the Bridges Section as the council is providing the majority of the finance.
Strengthening & replacement programme
As well as the assessment programme, a programme of strengthening or replacing sub-standard structures is being undertaken. These structures are being designed to the latest national standards and are capable of carrying the latest heavy goods vehicles and where necessary abnormal loads. This work has so far involved the strengthening of over 50 structures.
These schemes have mainly consisted of replacing the decks of bridges and have ranged from a £7,000 strengthening of the service bays below the footways of a bridge deck to a £1.5M total bridge replacement.