Pre-release Materials 2025: Morecambe Bay Barrage Proposal (AQA GCSE Geography) : Revision Note

Morecambe Bay and Duddon Estuary Tidal Barrage

What is a tidal barrage?

• A tidal barrage is a structure built across an estuary or bay

• The structure contains turbines

  • The barrage allows water to flow into the bay or river during high tide

  • Water is then released at low tide

  • As the water moves it turns the turbines which are then used to generate electricity

• Tidal energy is a renewable energy source

• The best locations for tidal energy are those with large tidal ranges

Tidal barrage schemes in the UK

• There are several tidal barrage projects in development in the UK including:

  • Morecambe Bay and Duddon Estuary

  • Swansea Barrage

  • Mersey Tidal Power project

• A 2021 study found that tidal energy has the potential to provide 11% of the UK's electricity demand

Advantages and disadvantages of tidal barrages

Morecambe Bay and Duddon Estuary Location

• The proposed barrage is located across Morecambe Bay and Duddon Estuary in Lancashire

• The ebb tide can go out up to 12km forming the largest intertidal area in the UK

• It covers 310 km²

• The rivers Wyre, Lune, Kent and Leven flow into Morecambe Bay, and the Duddon Estuary is to the north-west

• The area is characterised by:

  • saltmarshes

  • sandflats

  • mudflats

  • sand dunes

  • shingle beaches

Why is it a good location for tidal energy?

• Morecambe Bay has one of the largest tidal ranges in the world

• At its greatest, the tidal range is approximately 10 meters

• There are extensive areas of mudflats and sandflats, which means large amounts of water can be held to generate power

Morecambe Bay and Duddon Estuary tidal gateway project

• The proposed tidal gateway project is a £10 billion scheme

• The plan was proposed by the Northern Tidal Power Gateways project

• This is a 'multi-use development' which will provide energy but also improve transport infrastructure in the region

• The project would create two tidal barrages:

  • Barrage one will be 14km, across Morecambe Bay from just south of Morecambe to south of Barrow in Furness

  • Barrage two will be 5.5km across the Duddon Estuary from north of Barrow in Furness to Millom

Energy generation

• The tidal gateway project will include 132 turbines

  • The turbines will have a lifespan of 120 years

• The turbines would generate eight million megawatt hours of energy – sufficient for an estimated two million homes

Transport infrastructure

• The barrages would include a dual carriageway forming new transport links

  • This would link the M6 to the east of, Lancaster and Morecambe to the A590 in Barrow-in-Furness and the A595 into Cumbria

  • It is estimated that this will reduce the distance between Lancashire and south Cumbria by 50%

  • Travel time is estimated to decrease by 75%

• This would reduce:

  • fuel use by 750,000 litres each year

  • congestion on the M6

Social impacts

• Improved mobility, people will be able to travel more easily to other areas

• Better healthcare access

• Improved infrastructure will enhance people's quality of life

Economic impacts

• It is anticipated that over 7,000 jobs will be created in construction and 6,000 on-going jobs

• Increased recruitment for industries in south and west Cumbria

• Reduced regional inequalities, boosting local economies

Environmental impacts

• The barrages will include fish passes to allow fish to move between the open sea and the area behind the barrages

• Reduced CO² emissions

• Protection against coastal flooding and sea level rise

• Impact on the habitats and feeding patterns of shrimps, eels, and fish as well as those of local and migrating birds

• Harm to wildlife caused by contact with the turbines

Morecambe Bay and Duddon Estuary environment

• The intertidal area of Morecambe Bay and Duddon Estuary is an internationally important habitat for waterfowl and seabirds

• It is an important site for migratory birds such as oystercatchers, curlews and little terns, as well as native birds and marine life

  • It is estimated that over 250,000 birds use the Morecambe Bay area for feeding every year

• The area has high biodiversity levels due to the wide range of habitats

  • The RSPB lists Morecambe Bay as one of the most important areas for bird life in Europe

  • Over 25% of the UK natterjack toad population lives on the sand dunes around the bay

  • Over 33% of the UK orchid species are found in the area, including the rare Lady's Slipper Orchid

  • The area is an important habitat for butterflies and moths, including two of the fritillary butterfly species which are in population decline

  • The area also has the only grey seal colony in Cumbria

• There are several nature reserves and RSPB sites around Morecambe Bay and Duddon Estuary

• Morecambe Bay is a designated:

  • Special Area of Conservation (SAC)

  • Special Protected Area (SPA)

  • Site of Community Importance (SCI)

  • Marine Protected Area (OSPAR)

  • Ramsar wetland site

• It also has several Sites of Special Scientific Interest (SSSI)

• Duddon Estuary is also part of the SPA