One of the main routes south from Douglas is to be shut for around 12 months.

Pulrose Bridge is to be replaced in a £3.4m project that is scheduled to begin in March.

It means motorists will not be able to drive from Peel Road via Pulrose Road and Groves Road to New Castletown Road.

The current bridge was built in 1931 and the government says that it is neither practical nor economically justifiable to extend its life further.

In 2015 the River Douglas broke its banks and the bridge couldn’t cope with the amount of water rushing under it.

Its current construction causes a bottleneck in the river catchment, leading to flooding in upstream areas, which include the power station in Pulrose and the National Sports Centre.

While the existing bridge sits on two piers almost in the centre of the river, its replacement will feature load-bearing structures much closer to the banks and will also be raised by 70cm.

The wider channel will improve flow and reduce the possibility of debris causing blockages.

The bridge’s highway will feature cycle lanes on both sides, linking Peel Road with the heritage trail and Nunnery cycle routes.

The Department of Infrastructure says it will have a ’design life’ of 120 years.

The Department of the Environment, Food and Agriculture has been consulted regarding environmental issues relating to tree removal, river working and fisheries.

Electricity, water and telecoms connections will be diverted and reconnected while maintaining supplies as part of the scheme.

Gas diversions will take place before the main work begins.

Infrastructure Minister Tim Baker MHK said: ’The current bridge has served Douglas well since 1931 and is ready to be replaced by one which will meet the needs of our 21st century community.

’The department will be working in partnership with Manx Utilities and private contractors on an extremely complex programme to future-proof power and telecommunications connections and increase our resilience to the effects of climate change.

’Traffic diversions will be required but the programme has been designed to ensure any disruption will be kept to a minimum at the same time as delivering the scheme safely.’

Pedestrian access between Peel Road and Pulrose will be maintained throughout, while diversions and temporary routes for motorists will be fully signposted.

Businesses and property owners in the surrounding area have been told about the plans by the Department of Infrastructure.

A temporary entrance to Riverside Trading Estate will be created through Hills Meadow to enable customers requiring vehicle access to easily reach businesses while work takes place.

Pedestrian access to the estate will be unaffected and an area of The Bowl car park will include reserved parking for Riverside customers.

Vehicle access to Middle River Industrial Estate and Douglas Golf Club will be maintained via Groves Road and Pulrose Road while the closure is in place.