Widnes Salt Marsh

View of the old bridge from the salt marsh

Sunshine at last! Armed with my sunglasses and wellies I was fully prepared for what the urban salt marsh in widnes had to offer! Arriving at The Waterloo Centre in Widnes at around 10:30 we were welcomed by Damian Smith who specialises in the ecosystem services the salt marsh provides.

What is the salt marsh?

Salt marshes can be defined "as intertidal areas of fine sediment transported by water and stabilised by vegetation. Once a cover of vegetation has become established the rate of sedimentation (accretion) frequently increases as more of the incoming sediment is intercepted and trapped by the increased surface roughness" (JNCC)

Or more simply... "A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open salt water or brackish water that is regularly flooded by the tides. It is dominated by dense stands of salt-tolerant plants such as herbs, grasses, or low shrubs"

Widnes salt marsh
The salt marsh is located on the banks of the Mersey estuary. The map below shows its location.

The site is currently in its third year of conservation grazing using English Longhorn cattle. Research by Damien Smith (who showed us around) is being undertaken regarding its effectiveness in terms of improving the ecology of the site for plant and bird diversity. Last year a pair of Redshank and a pair of Lapwing reared chicks in the grazed area. Six fenced enclosures also show the positive effects of the grazing.

The Mersey Gateway Project

Special tape to prevent birds from nesting in the area

The Mersey Gateway is a new bridge that will be constructed over the estuary to bring about much needed traffic relief for the existing Silver Jubilee Bridge. Whilst construction of the bridge may bring damage to areas of the salt marsh a new charity - The Mersey Gateway Environmental Trust - which has been created to promote the conservation, protection and improvement of the environment across a 1600 hectare area of the Upper Mersey Estuary running all the way from the new bridge up river as far as Warrington.
This project not only aims to maintain and restore the saltmarsh habitat but also promote the ecosystem services the site can provide.

Ecosystem services
"Ecosystem services are the processes by which the environment produces resources utlilised by humans such as clean air, water, food and materials"

The Millennium Ecosystem Assessment categorised ecosystem services into 4 groups

1. Supporting - The services that are necessary for the production of all other ecosystem services including soil formation, photosynthesis, primary production, nutrient cycling and water cycling. 
2. Provisioning - The products obtained from ecosystems, including food, fibre, fuel, genetic resources, biochemicals, natural medicines, pharmaceuticals, ornamental resources and fresh water;
3. Regulating - The benefits obtained from the regulation of ecosystem processes, including air quality regulation, climate regulation, water regulation, erosion regulation, water purification, disease regulation, pest regulation, pollination, natural hazard regulation;
4. Cultural -  The non-material benefits people obtain from ecosystems through spiritual enrichment, cognitive development, reflection, recreation and aesthetic experiences – thereby taking account of landscape values;

Industrial works near the salt marsh

During the construction of the bridge and after it has been completed the charity hopes that the saltmarsh will provide many ecosystem services to the local communities such as - Provisioning - in the form of meat and dairy from the cows that graze the site, water for cooling industrial processes occurring near the site, and immobilisation of pollutants, Regulating services such as climate regulation via carbon uptake,and water purification from surrounding industrial processes with also Cultural services such as wild fowl hunting and leisure such as hunting/running - helped with the introduction of wooden boardwalks to the site. Whilst all changes would also see an increase in the richness of diversity of the site.

This project shows how other large scale constructions should take place. Research into the surrounding environment should be pivotal in negotiations to mitigate the damage caused.  

The shore line

Plane flying over the site

Damien Smiths research paper can be found here