Hurst Spit to Lymington project information page

Background

Who

The Environment Agency in partnership with New Forest District Council, Hampshire County Council and Natural England, with expert support from JBA Consulting, are exploring a sustainable future for the coastal frontage between Hurst Spit and Lymington in relation to flood and coastal erosion risk management. This will be known as the Hurst Spit to Lymington Strategy.

Where

This coastal frontage of focus is located within the New Forest National Park and extends from and includes Hurst Spit in the west, encompasses Keyhaven and Pennington Marshes, extending up the Lymington River to the east.

As this is a significant stretch of coastline, it will be sub-divided up into 9 individual management units which are discrete areas with broadly similar characteristics.  The use of management units will help facilitate a targeted approach to flood risk management.

(Image above) Hurst Spit to Lymington Strategy Management Units

What

The Hurst Spit to Lymington Strategy aims to investigate how to respond to the significant challenges facing this area of coastline now and in the future.

A key purpose of a strategy is to recommend options to manage erosion and coastal flood risk which are sustainable in the longer term.  It will outline a programme of future projects whilst also providing the high-level justification for that future work.

As the defences are likely to require work at different points in time, a strategy will allow a phased approach to deliver suitable work.  It will also highlight when investment is required to help draw in the significant external funding required at the appropriate time. 

This strategy will look forward to the next 100 years and appropriately explore what an adaptive coastline could and should look like. This is the start of a very forward-looking strategy that we hope will provide opportunities to protect, strengthen and enhance the environment in this area for future generations.

Coastline characteristics

The Hurst Spit to Lymington coastline is characterised by large areas of low-lying coastal habitats, including mudflats, saltmarsh and vegetated shingle.

Image below: low tide near the sea wall

Image below: Saltmarsh

The existing defences, as well as protecting local communities, protects large areas of coastal grazing marsh and coastal lagoons.

Image: Lagoon

The habitats and the species which can be found along this section of coast are of international importance. The rich biodiversity creates the stunning landscape, which is accompanied by cultural and historical heritage of significant status. The area attracts substantial visitor numbers and is enjoyed by a range of recreational users, for activities such as walking, sailing and fishing. These factors, along with natural coastal processes, will need to be carefully considered as the strategy develops.

Flooding

The predominant flood risk is from the sea; however, risk of river flooding is also present, as well as a risk of surface water flooding in the more built-up areas. This strategy will investigate all local flooding mechanisms to ascertain if a response is required.

Challenges facing the coastal frontage: what is the problem? More Information

Sea levels are expected to rise over 1 metre along the south coast in the next 100 years due to climate change. Being able to respond to this challenge will be key for safeguarding our coastal communities and environments for the future.

This coastline is a highly dynamic environment and change is a common occurrence. However, climate change could lead to impacts that are detrimental to both local communities and the environment.

As sea levels rise, not only will flood risk increase to properties, infrastructure and low-lying land, but it will also increase the impact on the designated habitats and the species they support.

Hurst Spit and the flood embankments are managed as coastal defences by New Forest District Council and the Environment Agency respectively.

By dissipating wave energy, Hurst Spit shingle bank currently offers protection to both the flood embankments and the low-lying designated habitats behind it.

Image: Drone footage Hurst Spit

Hurst Spit is becoming increasingly vulnerable to damage due to the net loss of shingle. On occasion, emergency repair works have been required, such as following the Valentine’s Day Storm in 2014. The vulnerability of the spit puts the flood embankments and the habitats and species which it protects at risk.

The situation is further complicated by the fact that the flood embankments combined with sea level rise are creating a process called coastal squeeze. The presence of the flood embankments prevents coastal habitats moving inland as sea levels rise. Where natural retreat of habitats inland is prevented, it results in the loss of coastal habitats, which in this instance is mostly saltmarsh. The loss of large areas of this important saltmarsh habitat will have significant consequences for wildlife and local communities. Saltmarsh is known to act as a natural flood defence through stabilising the coastline and dissipating wave energy. It is also very good at taking carbon out of the air and storing it. The decline of these valuable habitats has already begun and will only continue if opportunities cannot be identified.

In time, and without further recharging of the shingle, the protection offered by Hurst Spit is likely to reduce, exposing the intertidal habitats and flood embankments to higher wave energy. This will lead to a decline in the condition of the embankments making them more susceptible to damage from the sea. Although maintained regularly and functioning effectively at present, some long-term deterioration is beginning to show.

With the change in climate, more intense rainfall events are expected which will affect the rivers that drain out along this coast, increasing the risk of larger and more frequent flood events. Surface water flooding is also likely to occur on a greater scale than currently experienced.

What happens if we leave things as they are?

If the current status quo were to continue, it will become harder to maintain Hurst Spit and the surrounding embankments. Hurst Spit will need external sources of shingle to maintain its most effective size and shape. Shingle can be both expensive and time consuming to source especially when required for emergency works. At present, there are 54 properties at risk from coastal flooding along this frontage. This number is low in relation to the length of coastline and therefore does not justify significant funding from central government under current funding rules.

By maintaining the embankment and sea wall in their current alignment, this will cause the continued loss of saltmarsh due to coastal squeeze. As the condition of the embankments deteriorate, the coastal grazing marsh, lagoons and inland habitats are at ever increasing risk. The Habitats Directive places obligations on the UK Government to protect the designated sites and therefore the Strategy partners will need to explore potential options to do so.

We want to work alongside relevant stakeholders to explore addressing these challenges and discuss the future of this coastline as a collaborative community.

Hurst Castle

In February 2021, a section of wall on the castle collapsed after the sea exposed and undercut its foundations. English Heritage are working on a major project to protect and bring stability to the castle. The repairs to Hurst Castle are a separate project to our Strategy.

The long term works at the castle have implications on the Hurst Spit to Lymington Strategy and vice versa. The Strategy team will continue to hold discussions with English Heritage as both pieces of work progress. English Heritage are also a member of the Stakeholder Advisory Group (StAG) and continue to input into the Strategy via this forum as well as through direct meetings.

Further information on the project can be found on the English Heritage website Protecting Hurst Castle | English Heritage (english-heritage.org.uk)