SEFTON and WEST LANCASHIRE Annual Local Monitoring Report 2015

SEFTON AND WEST LANCASHIRE Annual Local Monitoring Report 2015

Final Report July 2016

Sefton Annual Local Monitoring Report 2015 Final Report July 2016

Produced by the Flood & Coastal Erosion Risk Management Team

Locality Services Commissioned

3rd Floor, Magdalen House

30 Trinity Road

Bootle

L20 3NJ

Tel: +44 (0)345 140 0845

e-mail: [email protected]

This report has been prepared by Sefton Metropolitan Borough Council in accordance with the instructions of their client, the Flood & Coastal Erosion Risk Management Team. Any other persons who use any information contained herein do so at their own risk.

Ordnance Survey mapping and aerial photography included in this report is provided by Sefton Council under licence in order to provide specialist coastal monitoring services. Persons viewing this mapping should contact Ordnance Survey copyright for advice where they wish to licence Ordnance Survey for their own use.

Oblique Aerial Photography is provided under open licencing by the North West and North Wales Coastal Group.

Document History Record

This report has been issued and amended as follows:

Issue Revision Description Date 1 0 Draft 23/06/2015 2 1 Final 13/07/2016

Addressee Sefton Council Audience Coastal/Environmental Engineers/Students/Internal staff Contributor(s) Wave data and Tide data provided from SANDS internal database (Sefton Council) Coverage Coastal Frontage: Seaforth to the River Ribble Creator Sefton Council Date Created: 2015-06-16 Draft Issued: 2015-06-23 Final Issued: 2016-07-13 Description Report on data, the behaviour of coastal processes and comparison with previous years’ data Format Text, WORD, Pdf Identifier 2015_SMBC_Proc Keyword Sefton, West Lancashire, Ribble, Coastal, Monitoring, Local, NWRMF, CERMS Language English Location Sefton Metropolitan Borough Council, Magdalen House, 30 Trinity Road. Bootle. Mandate North West Regional Monitoring Framework Publisher Sefton Metropolitan Borough Council Relation 6th in series of annual and process reports Rights Copyright Sefton Metropolitan Borough Council Status Final Subject Coastal Monitoring Title Sefton & West Lancashire Annual Local Monitoring Report 2015 Type Text/report Date of metadata 2016-11-21 update

Sefton and West Lancashire Annual Monitoring Report

Contents:

1.0 Background 1.1 Governance 2.0 Introduction 2.1 Purpose 2.2 Key summary points from this report 2.2.1 Planned actions from the SMP 2.2.2 Uncertainties and issues 2.2.3 Recommendations for additional actions 2.2.4 Potential influences on SMP policies 3.0 Conceptual Model Liverpool Bay 3.1 How Liverpool Bay Works 3.2 What we expect to see happen in any one year 4.0 Crosby to Hightown Area Summary 4.1 Baseline Information 4.2 Site overview 4.3 Current (SMP2) policy (adopted 2010) 4.4 Policy and approach (from 2010) 4.5 Key assumptions made during development 4.6 Summary of behaviour 4.7 Risk assessment 4.7.1 What would risk look like 4.8 Uncertainties and issues 4.9 Planned actions from the SMP 4.10 Recommendations for actions 4.11 Potential influences on SMP policies 5.0 Formby Dunes Area Summary 5.1 Baseline Information 5.2 Site overview 5.3 Current (SMP2) policy (adopted 2010) 5.4 Policy and approach (from 2010) 5.5 Key assumptions made during development 5.6 Summary of behaviour 5.7 Risk assessment 5.7.1 What would risk look like 5.8 Uncertainties and issues 5.9 Planned actions from the SMP 5.10 Recommendations for actions

5.11 Potential influences on SMP policies 6.0 Southport Area Summary 6.1 Baseline Information 6.2 Site overview 6.3 Current (SMP2) policy (adopted 2010) 6.4 Policy and approach (from 2010) 6.5 Key assumptions made during development 6.6 Summary of behaviour 6.7 Risk assessment 6.7.1 What would risk look like 6.8 Uncertainties and issues 6.9 Planned actions from the SMP 6.10 Recommendations for actions 6.11 Potential influences on SMP policies 7.0 West Lancashire Area Summary 7.1 Baseline Information 7.2 Site overview 7.3 Current (SMP2) policy (adopted 2010) 7.4 Policy and approach (from 2010) 7.5 Key assumptions made during development 7.6 Summary of behaviour 7.7 Risk assessment 7.7.1 What would risk look like 7.8 Uncertainties and issues 7.9 Planned actions from the SMP 7.10 Recommendations for actions 7.11 Potential influences on SMP policies

1.0 Background

1.1 Governance

Sefton Council is a Maritime Authority and Lead Local Flood Authority and as such has completed a Strategy setting out how it will manage flooding and coastal erosion in its area. Sefton Council’s vision in relation to this service area is ‘To improve the health and wellbeing of our communities through joint management of flood and coastal erosion risk’. The Council will deliver this through four key activities:

• Understanding risk to our communities • Avoiding increase of risk to our communities • Reducing risk to our communities • Reducing consequences to our communities

This report supports the delivery of the Strategy and will be linked back to the strategy. The Shoreline Management Plan is reflected in this strategy.

Figure 1: Management of flood and coastal erosion risk Sefton

West Lancashire Borough Council is a Maritime Authority and is a partner in the development and delivery of the Shoreline Management Plan. This report will help inform any decisions they may need to take to manage risk to their communities.

The Environment Agency has a role both in terms of tidal flooding and an overview in relation to the delivery of the Shoreline Management Plan. This report will provide evidence to them in relation to the delivery of the Shoreline Management Plan and also provide supporting evidence for any management decisions they may take within the Ribble Estuary.

The Shoreline Management Plan covers the area from the Solway Firth to the Great Orme (North West England and North Wales) and sets out the long term policy for the management of the coast in relation to tidal flood risk and coastal erosion. It sets the policies out over three time-periods (0-20, 20-50 and 50-100 years) but these are indicative only. A change between policies in different time-periods might be triggered by storm events, failure of defences, climate change or other changes in circumstances.

The polices are:

Policy Option Description Hold the line By maintaining or changing the current standard of protection. This policy includes those situations where work is carried out in front of the existing defences (such as beach recharge, rebuilding the toe of a structure, building offshore breakwaters and so on) to improve or maintain the standard of protection provided by the existing defence line. It also includes work behind existing defences (such as building secondary flood defences) where this work would form an essential part of maintaining the current coastal defence system.

Advance the By building new defences on the seaward side of the original defences. Use of line this policy is limited to those policy units where significant land reclamation is considered.

Managed By allowing the shoreline to move backwards or forwards, with management realignment to control or limit movement (such as reducing erosion or building new defences on the landward side of the original defences).

No active Where there is no investment in coastal defences or operations. intervention

Table 1: SMP policies

The Maritime Authorities responsible for the Shoreline Management Plan aim to keep it relevant by regularly reviewing and updating the evidence upon which the policies are based and where necessary reviewing the policies. They will co-ordinate this through the North West and North Wales Coastal Group, the Northern Coastal sub-group and Liverpool Bay Coastal sub-group. This report will contribute to that process.

Policy Option Description

2.0 Introduction

2.1 Purpose

The purpose of this report is to review our policies and actions for coastal defence as set out in the Shoreline Management Plan (SMP) and supporting documents. To do this we will review our conceptual understanding of coastal processes as it forms the baseline for the development of our policies. We will also review progress against our action plan and compare this against what is happening on the coast (natural and human activity) to see if it needs updating in relation to the activities set out or their timing.

To achieve this purpose this report will summarise our understanding of coastal processes, our policies and our action plans based on the following documents:

• Local Flood Risk Strategy and coastal erosion

• Shoreline Management Plan (SMP)

• Crosby to Formby Point Strategy

• Regional Process Report • CETASS (Cell Eleven Tide and Sediment Study) • Estuary Reports • Past Local Process Reports • Sefton Coast Adaptation study • Formby Point Erosion Report • Formby Point Caravan Site Report

Reference should be made to these documents if you would like more detail on how our understanding, policies and actions have been developed. We do not expect our understanding or policies to change greatly year to year but the action plan will be updated as progress is made. This material will be reviewed against available information, for actions this will be up to the date of the report, for processes it will be based on the calendar year preceding this report. This will include changes on the coast, both natural and human, and actions undertaken to progress our policies. The monitoring of natural processes is based upon extensive data collection and analysis which is available in digital form but for the purposes of this report only the summary of the analysis is considered.

2.2 Key summary points from this report

2.2.1 Planned Actions from the SMP

• Review Crosby to Formby Point Strategy • Develop management plan for the Alt Training Bank • Review and update of the Sefton Coast Management Plan • Implementation of Hesketh Outer Marsh scheme

2.2.2 Uncertainties and issues

• Understanding sediment movement and in particular the impact of existing and potential control structures – for example groynes and outfalls • Understanding the failure mechanisms and timing for current formal defences • Understanding the impact of continued change of Formby Bank • Quantities of sediment arriving on the beach from offshore • Wave conditions occurring directly in front of dunes currently unknown. • Process driving change on the Formby frontage • Are previous long term trends still relevant on the Formby frontage? • Quantities of sediment being moved into and within the Ribble estuary • Changes in lower foreshore conditions between marsh edge and channels around Ribble Estuary • Changes in the area of the saltmarsh at Southport • Movement and evolution of the Bog Hole Channel • Movement of the main channel in the Ribble Estuary

2.2.3 Recommendations for additional actions

• Monitor Timber Breastwork at Crosby • Review historical data for Alt Training Bank • Upgrade risk rating for the area between the Coastguard Station and the pumping station between Crosby and Hightown from medium to high • Record maintenance activities and costs for specific assets • Review dune management work • Review long term erosion rates • Review management of surface water around Shore Road to Weld Road • Monitor impact of Hesketh outer Marsh Scheme

2.2.4 Potential influences on SMP Policies • Need to review Crosby to Formby Point strategy in the light of changed funding regime and concern over contamination • Identify potential links and opportunities between actions in the Crosby to Formby Point Strategy and Council aspirations for Crosby Coastal Park • Performance of Hesketh Outer Marsh Scheme

3.0 Conceptual Model Sefton Coast

3.1 How the Sefton Coast works

Sefton Coast lies between the Mersey Estuary to the south

and the Ribble Estuary to the north within Liverpool

Bay, its beaches are mainly sand with some mud Did you know?

and limited areas of artificial shingle. The smaller Beaches are made of sediment; estuary of the River Alt emerges at Hightown. this is loose material in a variety of The Mersey Estuary requires walls and dredging to sizes. This can be mud, sand or maintain the channel for shipping. This has led to a shingle. Sand is the main material deepening of the Crosby and Queens Channel and found on the Sefton Coast. Shingle is normally large stones that have growth of Taylors Bank. been rounded and smoothed by the The Ribble Estuary has been significantly changed action of the waves tumbling them. by humans both through the trained and dredged

channel to the north side of the estuary and the land that has been reclaimed on the south side.

This has led to growth of saltmarsh on the south side of the estuary, particularly noticeable from the Crossens Channel through to Southport Pier.

The River Alt Training Wall acts to divert the river out to sea. In the past the river used to run along the shore to the south before heading out to sea. It also acts as a partial barrier to the alongshore movement of sand and shingle.

Did you know?

Saltmarsh is formed where there is little wave energy. This allows mud to settle on the beach. The seeds of plants in the water get deposited on the mud where they grow, sometimes they will get washed away but other times they will establish themselves. When established the plants trap more mud leading to a slow (10-28mm per year) increase in level of the saltmarsh. As the saltmarsh increases in level it gets covered by fewer tides and this Figure 2: River Alt Training wall allows a wider variety of plants to establish. The saltmarsh and plants are beneficial for coastal defence as they reduce the wave energy that reaches the shore.

Did you know?

Longshore Drift is where sand or shingle is moved along the beach by Waves reaching this coast are relatively small the action of the incoming waves. because this area is sheltered by the Isle of Man, Waves may approach the shore at an Anglesey and Ireland. The main direction that angle pushing the sand or shingle up waves come from is WNW with the majority the beach, as the sea falls back it drags being less than a metre in height (20-30% being the sand or shingle back down the between 1 and 3 metres and only 1% over 3 beach at right angles to it. As this metres in height). The shape of the shore is process is repeated it moves the sand or contributing to the erosion experienced here as the shingle alongshore as long as there are energy is concentrated by refraction. In areas such no barriers. as Ainsdale through to Birkdale the waves are dispersed (diffraction) because of the shape of the shore, this allows sand to build up here and develop into a small dune system.

The tides tend to push sediment into the estuaries and towards the coast. The difference between the highest and lowest tides is 9m metres in height. Where the beach is very flat this can mean that the tide can go out up to 3kms, at Southport for example.

Sand and mud is moved onshore by tides and waves but also wind when the shore is exposed at low tide. The coast is mainly sand apart from at Southport and the Ribble Estuary where the conditions bring in mud as well as sand. As it reaches the shore it generally moves in a north or south direction from Formby Point.

Sand dunes across Formby Point erode when the tide reaches them. They erode more when large waves occur at the same time as a high tide. When the water reaches the dunes it causes the sand to slip down into the water, either carrying it away or spreading it across the beach. The vertical face that is left will continue to slip down over the next few days until a slope is formed. This may build up when there is wind blowing across the shore Did you know? when the tide is out and the sand is dry. Sand can accumulate at the shoreline and sometimes blow Ridges and Runnels are a further into the dunes. A tide needs to be over feature formed by the waves as 4.67m OD to reach this shoreline and about 10% the tide comes in across the will do this. As Formby Point erodes and changes beach. The ridge is a high point shape we would expect this to alter the way that the and the runnel a trough or low waves approach the shore and the rates at which the point. The difference between shoreline and shore levels will change in that area. the low and high point may be anything from 0.3m to 1.3m There are a series of ridges and runnels (channels) on the shore at Ainsdale, Formby and Crosby, these can be significant running for hundreds of metres in length and with a height difference between the ridge and runnel of 0.3m to 1.3m. They typically align with the waves coming in to shore (see conceptual map).

Did you know?

Sea level rise is happening as a result of climate change. This will result in our tides

reaching a higher level; especially during storm events. This will have an impact on beaches and the shoreline at the top of the beach. Where this is dunes we expect erosion, where this is defences we expect more water to go over the top of them.

By the end of the century we expect sea Figure 3: Ridges and runnels at level to have increased by about a metre. Formby Point

3.2 What we expect to see happen in any one year

Crosby – the shoreline position is relatively stable but the shore height might go up or down by 0.5m in any location in a year. Some of this variation is due to the ridge runnel system. Along the length running south from the swimming baths to the docks, dunes have built up in front of the defences and sand blows over the defence and promenade. If the Council stops clearing the sand from the promenade we can expect the sand to form a dune that completely covers the defence and promenade. The defences are old (built in the 1960’s and 70’s) and will continue to deteriorate. Typical damage is concrete edges falling off, timbers splintering or breaking free, hand-railing being damaged and the promenade surface moving.

Hall Road to Hightown – the shore along this length tends to erode, moving landwards at between 0.3m to 1.0m per year but this can be significantly larger after storm events. There is no formal defence and where it is eroding for the majority of the length it is ground that has previously been filled with building debris. The release of these manmade materials means the area will look derelict, and provide some health and safety issues, although the rubble does act as an informal defence. At Hightown the natural dunes are slowly eroding, supplying some sand to the beach. We would expect a slow loss of material from this area (circa 1,000m3/year) and after Did you know? storm events some increase in erosion of the dunes. Tides occur on a regular cycle every 12.25 hours. Each cycle the sea goes up River Alt to Ainsdale – Formby Point and down but the range, or difference erodes up to 3.7m in a typical year with between the high and low point will vary this change getting less as you head north both in relation to the point in the tidal and south. To the north and south of the cycle and the physical location. In coast there are hinge points where erosions Liverpool Bay we have a very large turns to accretion at up to 2.5m per year. range. The tidal cycle relates to the During storm events the whole of this length variation in tidal range in relation to the may lose sand and be eroded, the amount phases of the moon, this results in a depends on the direction the waves are coming sequence of smaller and larger tidal

from, their size and the height of the tide. At Formby one storm may erode 10-15m of the coast. As well as erosion there will be accretion during periods of high wind and low tides where the dunes will build back up. In some areas there is public pressure that will cause blow- outs, where the vegetation is damaged and the sand blows inland. Land managers may undertake some works to manage human pressure or to try and trap sand and stabilise the dunes. Where there is parking on the beach at Ainsdale we would anticipate that this will constrain any dune growth but this is mitigated by the regular movement of the parking area seaward.

Ainsdale to Southport – we expect this shore to move seaward over time, although as it develops into saltmarsh the rate of change will slow. Parking on the beach at Southport will limit the opportunity for saltmarsh to develop.

The Boghole channel is a local feature which is slowly changing position and can influence its surroundings as adjacent beach levels will be lower. Where previously the Boghole Channel had been linked to the end of the Pier it now appears to be completely detached. The sluice gates from the Southport Marine Lake have a local influence both in terms of keeping beach levels lower in the immediate area and tending to link to and anchor the Boghole Channel.

Southport to West Lancashire – This area is predominately saltmarsh where any change will be slow. We would expect some erosion of the outer edges after storms. Changes in height of the saltmarsh would typically be 10-28mm per year so will be difficult to observe in any one year. There is a longer term recovery of the area where the haul road for the old sand extraction plant is. This road is higher than the surrounding area and has a local influence on the movement and deposition of mud. As the road breaks down and the surrounding saltmarsh increases in height this influence will diminish. This area is also influenced by the Crossens Channel.

Did you know?

Definitions of the processes mentioned in the conceptual maps can be found in the

Appendix

Figure 4: Shallow waves Shore Road Ainsdale

Did you know?

There is risk associated with changes at the coast through flooding or loss of land and anything on that land. We can’t remove all risk so we have to manage it, to do this we focus our resources on the risks that have the largest consequences and are most likely to happen.

The consequences of flooding and coastal erosion include damage to features such as roads, sewers and houses. These don’t change much each year.

Things that might change the likelihood of something happening include changes in the condition of the defences, the level of the beach and the position of the shoreline.

We will review the risk against our monitoring and if it has changed we will take appropriate action. This could be to monitor the situation, to take physical action, to advise those at risk or in the case that the risk reduces we might reduce our monitoring.

Figure 5: Map showing conceptual model for the Sefton Coast 4.0 Crosby to Hightown Area Summary

4.1 Baseline Information

Total length: 10km Defended length: 8.5km Rock armour: 2.1km Concrete Sea Wall: 3.5km Rubble: 2.6km Sand Dunes: 1.8km Saltmarsh: 0.4km Sheet Piles: 0.3km

4.2 Site overview

Up until, the 1930s the shoreline between Bootle and Southport was a continuous natural dune belt interrupted only at Hightown where the River Alt discharged across the beach and then meandered southerly against the shoreline to Crosby. In the 1930s a training bank was built between Hightown and Blundellsands to deflect the course of the river channel south westerly. From the 1930s to the 1960s rubble was tipped between Blundellsands and Far Moss (just south of Hightown) to reinforce the eroded shoreline. In 1960 a formal timber coastal defence was built from near Hall Road West southerly towards Crosby. In 1970 the construction of the Royal Seaforth Dock created a barrier at the southern end of the frontage and following the subsequent construction of the Marine Lake at Crosby in the 1970s, a new sea wall that linked from the north end of Seaforth to Hall Road West was constructed.

At the present time this frontage is defended by concrete and rock sea walls between Seaforth Dock and Hall Road. From Hall Road the rubble shoreline continues for about 1.5km before giving way to the remnants of the dune belt at Hightown. Localised coastal defences exist around the Blundellsands Sailing Club. The Alt training bank also remains.

In past years the following work has been carried out:

• 700 tonnes of rock armour placed adjacent to the coastguard station at Hall Road (2002). • New revetment built in front of Blundellsands sailing club (2011) • Removing sand from Crosby and placing at Hightown in the line of the dunes of the 1970s (2011). • Planting grasses to stabilise the dunes at Hightown (2011). • Rock armour placed alongside the United Utilities outfall north of Blundellsands sailing club (2011). • Annually replacing damaged hand-railing, timber breastwork and concrete. • Dredging of Crosby channel undertaken by the dock authority both Capital and maintenance

4.3 Current (SMP2) Policy (adopted 2010)

The long term plan is to manage erosion risk to property and infrastructure if and when threatened by erosion but as far as possible allow natural processes to continue. Through adoption of this approach, accretion could mean that little intervention is actually required. Elsewhere, for example at Hightown, localised defence could be acceptable, in conjunction with holding the river channel away from the beach to prevent erosion. By managing erosion risk, the majority of the social objectives are met. The limited intervention required in the majority of areas also supports many of the natural objectives by allowing the dune system to provide a natural means of defence.

4.4 Policy and Approach (From 2010)

Location (Policy Unit) 2010-2030 2030-2060 2060-2110

8.1 Seaforth to Hold the Line – Hold the Line – Hold the Line – Mersey Estuary Only intervene where Only intervene where Maintain existing Pollution Alleviation assets are at risk. assets are at risk. defences to appropriate Scheme (MEPAS) Maintain existing Maintain existing standard. Maintain Alt MEPAS pumping defences to appropriate defences to appropriate training walls. Station standard. Maintain Alt standard. Maintain Alt training walls. training walls.

8.2 Mersey Estuary Managed Realignment Managed Realignment Managed Realignment Pollution Alleviation - - – Scheme (MEPAS) Allow natural Allow natural Only construct set back pumping Station to processes to continue, processes to continue, defences when assets Hightown with minimal with minimal within Hightown and intervention to intervention to /or railway justify. maintain outfalls maintain outfalls Allows natural deflecting the Alt deflecting the Alt processes to continue, channel away from the channel away from the outfalls deflecting the shore. shore. Alt channel away from the shore should be maintained.

8.3 Hightown to Hold the Line – Hold the Line – Hold the Line – mouth of the River Through limited Through limited Through limited Alt (east bank) intervention and dune intervention and dune intervention and dune management. Maintain management. Maintain management. Maintain Alt training walls. Alt training walls. Alt training walls. Additional training Additional training Additional training walls may be required walls may be required walls may be required to deflect the Alt to deflect the Alt to deflect the Alt channel in the future. channel in the future. channel in the future.

8.4 River Alt mouth Hold the Line – Hold the Line – Hold the Line – (east and west banks) Maintain channel Maintain channel Maintain channel to the Alt pumping training defences. training defences. training defences. station

Table 2: SMP policy Crosby to Hightown 4.5 Key assumptions made during development

• Future behaviour of the shoreline will depend upon the discharge regime for the pumped River Alt. It has been assumed that the training works will be maintained to hold the Alt Channel away from the shore. • Uncertainty surrounding the rates of accretion and potential benefits from preventing contamination and hence, consequence on the required level of investment to defend this frontage, will need to be explored as part of the supporting investigations detailed in the Action Plan. • Economic justification needs to be examined in more detail at strategy level and opportunities for co-funding need to be investigated. • Policy delivery may be compromised by funding prioritisation and therefore opportunities for co-funding need to be investigated. • The SMP policies will be subject to review if sea level rise predictions are changed.

4.6 Summary of behaviour

Across this section of shoreline waves generated by winds blowing across the Irish Sea are intercepted by the offshore Burbo sandbank and the Crosby channel and its training walls which modify their behaviour as they approach the shoreline.

On the east side of Crosby channel the beach between Seaforth and the River Alt training bank is characterised by peaks and troughs (ridges and runnels). To the north of the training bank the Formby Bank is a growing feature that limits wave heights as they approach the shoreline and the channel of the River Alt provides a barrier for sediment movement. Generally sediment moves into the frontage from the North and is prevented from moving out at the southern end by Seaforth Dock, it is assumed that a significant portion of the sediment flows into the River Mersey. The presence of the Crosby Channel limits significant inputs from the west.

High beach levels, particularly at the southern end of the section, provide conditions that give rise to windblown sand that feeds the dunes or is deposited on the promenade or hard surfaces. At the southern end from Seaforth Docks through to the swimming baths the dunes are growing in extent both alongshore and seaward. Sand blows inland building the dunes that exist behind the promenade. Without clearance of the sand from the promenade we would expect the dunes on the beach and the dunes behind the promenade to connect to form a single system. There is little long term change in the beach in this area although there is variation in beach levels between the Mean Sea level and Mean High Water Spring contours, typically of plus or minus half a metre. The behaviour of the beach is the same through to the Coast Guard Station. This variability is mainly due to the movement of the ridges and runnels.

During the winter storms (2013/2014) there was extensive overtopping around the section from the swimming baths through to the Coast Guard Station during the storm events. This resulted in some damage to the promenade surface where water pressure pushed the surface up, damage to some of the timber breastwork, concrete, the splash wall and hand railing as well as erosion to the dunes and areas of land behind the splash wall. The dunes and areas behind the splash wall have been left to

recover naturally but structural elements were repaired and emergency procedures were reviewed and updated.

Further to this some site investigation was undertaken to establish if the tie-bars identified in the design drawings for this section were present. They were present at some locations but not all.

The made ground north of the Coast Guard Station tends to form a cliff as it erodes with rubble to the front forming a shingle beach. Although we know that there is a dominant southwards drift of sediment there is a local drift of the rubble northwards, the scale and extent of this is unknown. The drift is not consistently northwards as the amount of rubble in front of the hard defences at the Coast Guard Station varies as it moves both north and south depending on the tides and waves. The material that drifts northwards tends to be sorted by size (typically brick size) and further north this more uniform material tends to take the shape that you would expect of a shingle beach.

Figure 6: Erosion north of Coastguard station following storm 2014

During the storms of 2013/14 there was extensive erosion along this length but it was variable in amount and the main area of concern is closer to the Coast Guard Station where the distance to United Utilities rising main and the Council’s cycle path is much less. Discussions have taken place

with United Utilities and other key partners both as part of longer term plans for managing coastal defence in this area and to discuss any short term issues arising from this.

Within this area we have the Alt Training bank which has been settling over time to the extent that there is a clear visual difference between levels along its length.

At Hightown beach where the scheme was undertaken in 2011 much of the sand placed as dunes has been redistributed within the system. The overall loss of material from the system since 2011 is 2600m3. Beach levels are higher but during the storms 2013/14 there was a significant redistribution of material and the dunes fronting the reed bed were heavily eroded allowing waves to enter the reed bed directly. The dunes in front of the reed bed are recovering but should continue to be monitored as should the volume of material in the system.

Formby Bank, west of the River Alt, is growing. Beach levels are increasing although there is some natural variability between the Mean Low Water Neap and Mean High Water Neap contours. This change ties in with the infilling of the Formby Channel and in the longer term will alter the wave energy reaching the shore as the waves shoal across this wide beach.

4.7 Risk Assessment

The primary risks arising from the behaviour of coastal forcing processes (wind, waves and tides) and the reaction of the shoreline (beach and dune changes, artificial defence conditions) across this frontage are:

• Overtopping of artificial defences causing flooding of the hinterland, • Breaching of artificial coastal defences, causing erosion of the shoreline • Erosion of dunes and cliffs providing potential pathways for water penetration into the hinterland • Wind-blown sand nuisance to people and property

The primary consequences of this behaviour are:

• Damage to and/or loss of property and infrastructure • Damage to environmental habitats • Release of contaminated material

The table below shows the overall risk rating(s) that apply within this section of frontage. Overall risk is defined from the probability of conditions/behaviour occurring and the consequences the conditions/behaviour would have.

Crosby – Hightown Overall Risk Rating SMP2 Overall Probability Consequence Policy Unit Section of Frontage Exposure Risk Index Index (11a) Rating Seaforth to Alt Training 8.1 High Medium Medium/High Medium Bank Alt Training Bank to 8.2 High Medium Medium Medium Hightown Hightown to River Alt (East 8.3 Medium Medium High Medium Bank) River Alt mouth (east and 8.4 west banks) to the Alt Low Low Medium/High Low pumping station. Table 3: Crosby to Hightown risk rating

4.7.1 What would this risk look like?

At Crosby (Seaforth to the Coast Guard Station) the main areas that we would expect to suffer Did you know? from overtopping are at the swimming baths and the car park adjacent to the Coast The rising main that runs from north to Guard Station. We would not expect this south moving sewage towards the to flood property but we would expect it treatment works in the docks serves a to make the promenade and car park significant area of Crosby. The erosion unusable. that occurred during the winter of 2013/14 has not only narrowed the The impact of extreme events could cause distance to this infrastructure but also damage along this frontage to all elements demonstrated the scale of erosion that can of the coastal defence structure and happen over a relatively short period of infrastructure behind the defence. The time. worst case scenario is a complete failure of a section of the defence which would quickly expand as material is washed away from behind the structure to either side.

From Hall Road to Hightown we expect erosion and overtopping during extreme events. This results in the release of contaminated material onto the beach and also throws debris up onto the area behind the beach. The main assets Did you know? at risk are the rising main for the sewer and the cycle track. There is significant uncertainty relating to the extent and location of erosion The Alt Training Wall was along this length with experience in 2013/14 showing that we can designed to deflect the Alt have up to 10m of erosion in some areas. A key risk area here is the seawards and it has and narrowest point from the cliff edge to the rising main also known at continues to serve this function the Mersey Estuary Pollution Alleviation Scheme (MEPAS) rising although there has been a long main. standing concern that it will breach at some point.

The Alt Training Bank is at risk of failing but it is not clear what the mechanism or consequences of such a failure would be although it would be reasonable to assume that it would increase the rate of erosion to the south.

We would expect Hightown to experience erosion during an extreme event as material is redistributed from the dunes to the beach. Key risk areas are the areas to either side of the sailing club where there is a risk of the defences being flanked. The spit of dunes to the front of the reed Did you know? bed has experienced erosion during extreme events (such as 2013/14) but does recover, however the reed bed being Typical Maintenance exposed to wave action is a potential risk as it would not be work has included expected to respond well. There are potential issues with the repairing guard railing, operation of outfalls both through the structure failing or the timber breastwork, outfalls being buried. concrete, joint filler, the promenade, splash wall and The mouth of the River Alt has a low exposure to waves navigation markers. although the condition of the banks needs to be monitored as it has the potential to experience erosion as a result of the operation of the pumping station.

4.8 Uncertainties & Issues

• Understanding sediment movement and in particular the impact of existing and potential control structures • Understanding the failure mechanisms and timing for current formal defences • Understanding the impact of continued change of Formby Bank

4.9 Planned Actions from the SMP

• Review Crosby to Formby Point Strategy • Develop management plan for the Alt Training Bank

4.10 Recommendations for additional actions

• Look at the feasibility of monitoring for movement at the head of the posts of timber breastwork and if possible implement. • It would be useful to review historic evidence and see if the original design or construction levels for the training bank can be established as a baseline for reference. There is still a need to establish its potential failure mechanisms, future design options and their implications on coastal processes. • Discussions are ongoing with United Utilities to determine both a short and long term solution but in the meantime consideration should be given to increasing the probability in the risk assessment for this area from medium to high. This would lead to an overall risk rating of high. • It is suggested that in future maintenance works be coded by area so that costs can be compared year on year for specific assets.

4.11 Potential influences on SMP policies

• Need to review Crosby to Formby Point strategy in the light of changed funding regime and concern over contamination • Identify potential links and opportunities between actions in the Crosby to Formby Point Strategy and Council aspirations for Crosby Coastal Park

Figure 7: Coastguard Station to Alt Training Wall

Seaforth to River Alt (11a 8) Action Plan as adopted 5/8/2010 – progress indicated in final column

ACTION PLAN Action Action Action Description, Outcome Progress to date Ref (to be approved)

1. Studies for policy area 1.1 Complete the Crosby to Formby strategy studies, An adopted strategy setting out a These were all completed in 2008. taking account of SMP findings and a more sustainable management approach. detailed habitats regulations assessment to determine the approach to delivery of coastal flood and erosion risk management.

1.2 In consultation with Natural England, develop a A management plan with suitable Indicative funding has been included in the Medium Term Plan to develop an more detailed approach to the management and triggers for action. approach. training of the Alt channel in order to minimise erosion risks to properties and infrastructure and the natural environment. 2. Studies for Policy Units: Investigate the hazard that the erosion of dunes Improved understanding of risk. The immediate risk has been reviewed and is being managed. A longer term PU 8.2 2.1 north of the MEPAS pumping station poses to approach to this risk is being worked on as part of the review of the Strategy. people and the environment from leaching or the release of contaminated materials.

3. Strategy 3.1 Finalise and adopt the Crosby to Formby strategy An adopted strategy setting out a The Strategy was approved in 2010. that defines details of approaches to managing sustainable management approach. The Strategy will be reviewed in the light of new funding arrangements and an the coastal defences. improved understanding of the risk associated with contamination and from erosion. There is an allocation in the Medium Term Plan for this in 2016/17.

4. Scheme Work 4.1(20 Hightown Coastal Defence Scheme Mitigate the impacts of coastal Works undertaken and completed in 2011/12 10) erosion in this area. 5. Monitoring (Data 5.1 Undertake estuary and coastal defence asset Data provided to CERMS provides The current programme (2011-2016) is being successfully delivered. Collection) monitoring in conjunction with Cell 11 Regional improved evidence base for future The application for the next five year programme (2016-21) has progressed Monitoring Strategy to inform strategy and future decision making. through the Project Appraisal Board (September 2015). SMP reviews

5.2 Environmental monitoring of designated habitats within international conservation sites to provide baseline data for future Habitat Regulations Assessments

6. Asset Management 6.1 Maintenance of defences and beach and dune Maintenance undertaken to The asset condition is deteriorating and it is costing more to maintain. management including management of public required standards. access.

7. Communication 7.1 Undertake consultation with key stakeholders and Participative planning. Completed as part of Strategy general public during strategy development. 7.2 Monitoring and management of Action Plans by NWNWCG reports on progress. An annual report has been submitted to DEFRA the NWNWCG to confirm SMP policies are put into practice. 8. Interface with Planning and 8.1 Advise local Planning Authority about SMP Coastal flood risks considered in The Local Plan will undergo an Examination in Public in November/December Land Management policies and flood and erosion risks so they can land use plans. 2015. be accounted for in the next revisions of land use The Coastal Change Management Area has been informed by the SMP policies plans in order to help manage residual risks from and information. flooding and erosion. Tidal flood risk has been considered within the Local Plan as part of flood risk from all sources.

8.2 Advise local Planning Authority about SMP Coastal flood risks considered in Planning applications are reviewed based on both coastal erosion and flood risk policies and flood and erosion risks so they can planning decisions. from all sources. take due account in planning decisions and aim to reduce the need to manage flood risk in future.

9. Emergency Response 9.1 Development, monitoring and review of Coastal flood risks considered in Following on from the winter of 2013/14 our response to high tide events was emergency response plans to prepare for over emergency plans. reviewed and amended with a High Tide Response Group being established along design standard events. with operating guidelines.

10. Adaptation/Resilience 10.1 Develop an adaptation strategy to manage risks Management of risk. An adaptation study was completed in 2010 and allow natural roll-back of assets located within or adjacent to the dunes to facilitate natural roll-back of the dune system.

11. Flood Forecasting and 11.1 Continue to improve flood risk maps and Improved flood warnings and risk Warning inundation modelling, particularly in areas where mapping, raising awareness of there are dunes and promenades and areas coastal risks. benefiting from these defences are not currently shown. 12. Habitat Creation and 12.1 Monitor progress with dune management and Improved understanding. RHCP is now a lower priority environmental mitigation restoration in PU 8.2 & 8.3 and link to dune habitat strand of RHCP. 12.2 Undertake a Habitat Regulations Assessment for Meet legal requirement. Completed as part of the Strategy the strategy and link mitigation to RHCP. 12.3 Seek opportunities for habitat enhancements Objectives set for strategy. This principle is adopted during the development of strategies and schemes. during strategy development as part of flood/erosion risk management works e.g. consider scrub control at Hightown within the Sefton Coast SAC.

NB Activities from SMP will be carried forward into medium term plans and carried out on a priority basis, subject to funding and approval. n/a = activity is part of authorities general duties, not funded through flood and erosion risk management routes. EA = Environment Agency; LO = land owners; NE = Natural England; NWNWCG = North West and North Wales Coastal Group; RHCP = regional Habitat creation Programme; SC = Sefton Council.Programme; SC = Sefton Council. Table 4: Action plan Seaforth to River Alt

Figure 8: Map showing conceptual of Crosby to Hightown 5.0 Formby Dunes Area Summary

5.1 Baseline Information

Total length: 8.9km Defended length: 0km Sand Dunes: 8.9km

5.2 Site overview

This frontage is undefended and consists of natural sand dunes. The present sand dune system dates from between 1400 AD and 1600 AD. During the 18th Century Formby Point accreted. In the early 1900s erosion began near Victoria Road. The effect of erosion, which continued throughout the 20th Century, influenced an increasing amount of the frontage. At present the shoreline is eroding from the vicinity of Lifeboat Road to somewhere between Fisherman’s Path and the Freshfield/Ainsdale boundary.

The Ainsdale National Nature Reserve was declared in 1965, and regular measurements of erosion commenced in 1969. Severe erosion occurred in the storm surge of November 1977. In 1978, the northern limit of erosion was 250 metres north of the Freshfield/Ainsdale boundary.

In the past ten years the following work has been carried out:

• Planting grasses to stabilise the dunes. • Sand trapping techniques used to control sand movement, such as fencing and placing of Christmas trees. • Building boardwalks to manage access over the dunes and prevent erosion of the dunes by visitors.

5.3 Current (SMP2) Policy (adopted 2010)

Allowing the natural evolution of this area is the long term plan, with minimal intervention if local problems occur, which may involve dune management or relocation of assets at risk.

By managing the natural roll back of the dune system the impacts on the human assets can be minimised whilst maintaining the natural character of the frontage.

5.4 Policy and Approach (from 2010)

Location 2010-2030 2030-2060 2060-2110 (Policy Unit) 9.1 Mouth of Managed Realignment Managed Realignment Managed Realignment the River Alt (west bank) to Allow the dune system to Allow the dune system to Allow the dune system to Weld evolve naturally with evolve naturally with evolve naturally with Road, limited intervention to limited intervention to limited intervention Southport manage dunes, and manage dunes, and to manage dunes, and (Formby dune manage adaptation in the manage adaptation in the manage adaptation in the system) erosion risk zone (such as erosion risk zone (such as erosion risk zone relocating paths and car relocating paths and car (such as relocating paths parks), subject to parks), subject to and car parks), subject to consents. consents. consents.

Table 5: SMP policy Formby Dunes

5.5 Key assumptions made during development

• It has been assumed that the littoral drift divide occurs in the vicinity of Formby Point, with net movement of sand away from Formby Point. Consequently, erosion will continue at Formby Point and accretion will continue to the north and south. • Uncertainty associated with the costs of this adaptive policy will need to be explored as part of developing a management strategy. • The SMP policy will be subject to review if sea level rise predictions are changed.

5.6 Summary of behaviour

Across this section waves are generated by winds blowing across the Irish Sea. Behaviour at the shoreline is variable with the southern part of the frontage affected by the position of the Queen’s /Crosby channel and Taylor’s Bank, which act to modify (shoaling and refraction) waves as they move towards the shoreline. Across the northern part waves approach the shoreline largely unhindered by offshore banks and channels, causing erosion. The beach profile is generally characterised by a series of peaks and troughs (ridges and runnels).

The limits and rate of erosion across Formby Point are changing over time with the southerly boundary between erosion and accretion moving gradually northwards and the average rate of erosion reducing. The changes in processes causing this reduction are not clear.

The section of frontage to the south of Formby Point to the River Alt at Hightown comprises an accreting upper foreshore and associated accreting dune belt. This section of frontage receives shelter from Taylor’s Bank and the Queen’s channel with material moved onshore or longshore adding to beach volumes here. Furthermore, in addition to marine processes, the wide inter-tidal zone provides areas of dry sand that remain above the normal high tide levels and provide material for transport by the wind. Both Formby Bank and Taylors Bank are increasing in height and extent over time.

The northern hinge point is around Fisherman’s Path, from here to Shore Road the position of the shoreline is stable at the southern end moving through to accretion as you head to Shore Road. The beach levels are variable between Mean Low Water Neaps and Mean High Water Springs Level contours due to the presence of ridges and runnels.

North of Shore Road through to Weld Road the coast has accreted significantly since vehicles were prohibited from this area in the early nineties. Because the accretion was rapid it initially formed saltmarsh which has turned into fresh water marsh as sand dunes have formed to the front of it. The beach has accreted over time although in recent years is relatively stable with annual variation in beach levels due to ridges and runnels between the Mean Sea Level and Mean High Water Springs contours. As you head towards Weld Road this natural variation in beach levels reduces in extent and is focussed around the Mean High Water Neap contour. There are a number of surface water outfalls along this length and the accretion is having a negative impact on their operation.

During the storms of 2013/14 there was extensive and significant erosion but inspections have indicated that recovery is occurring following on from this. Given the scale of the storm events this erosion is less than we would have expected and our current conceptual understanding for this area needs reviewing.

Dune management work has continued in the area of Victoria Road in an attempt to slow down the erosion and windblown sand that will result in the caravan site no longer being viable. A more detailed assessment of the change here is available in a separate report located in the Appendix. There is still a need to understand the impacts of dune management work.

Did you know?

Dune Management is typically undertaken by:

• Introducing something (fencing or Christmas trees) to slow the wind speed down so that the sand being carried drops out of suspension • Planting of marram grass as a good dune building plant • Using signage and fencing to encourage people not to disturb the area

Whilst it is known to be good for repairing areas damaged through human pressure and it has a clear

Figure 9: Victoria road where there short term impact the longer term impact is not well is heavy dune management understood.

Figure 10: Post storm erosion at Formby

Formby Average Beach Level Changes 2001-2013 400

300

200

100 Formby South Formby North Beach Level Change (mm) Change Level Beach 0

-100

-200 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 Date

Figure 11: Graph showing beach level changes

5.7 Risk Assessment

Erosion of dunes providing potential pathways for water penetration into the hinterland

The primary consequences of this behaviour are:

• Damage to environmental habitats. • Impact on local dune infrastructure (fencing, boardwalks etc.) • Loss of designations • Financial implications • Health and safety • Impacts on tourism

Formby Overall Risk Rating SMP2 Overall Policy Probability Consequence Section of Frontage Exposure Risk Unit Index Index Rating (11a) River Alt, Hightown to Weld 9.1 High High Medium/High High Road Table 6: Risk rating Formby Dunes

5.7.1 What would this risk look like?

Erosion of dunes following extreme events can look dramatic with steep cliffs to the face of the dunes and damage to infrastructure such as boardwalks. There is an element of recovery over the following days and weeks as these steep faces slump and sand blows in. For this reason it is important to view the impact of such events over the longer term.

Loss of dunes results in a loss of habitat both through loss of area of the dunes themselves and their natural response to ‘roll-back’ covering the habitats behind them. This can become increasingly problematic as the dune habitat rolls back towards stable or fixed features such as trees, houses or caravan sites.

5.8 Uncertainties & Issues

The following uncertainties have arisen from the data monitoring programme and analysis of the data collected:

• Quantities of sediment arriving on the beach from offshore; and

Did you know?

• Wave conditions occurring directly Erosion rates: There has been a working in front of dunes currently assumption that the erosion rates around unknown. Formby Point are linear in the long term but • Process driving change on this variable in the short term due to the impacts frontage of storms. Similarly the hinge points where it • Are previous long term trends still relevant? changes from erosion to accretion have been • Impacts on habitats and assumed to be reasonably stable in their designations location. Monitoring over the last ten years and in particular in relation to the storm events over the winter of 2013/14 challenges 5.9 Planned actions from the SMP these assumptions.

• Review and update of the Sefton Coast Management Plan

5.10 Recommendations for additional actions

• Review dune management work that has been undertaken to see if we can understand both the short and long term impact of this activity. • It is recommended that a more detailed review of the data be undertaken to better understand if we are seeing a change in past trends and to see if we can identify the processes leading to this change. • Review current approach to surface water drainage in this area and develop options that take into account the changing beach conditions. • Review habitat management

5.11 Potential influences on SMP policies

• Any revision of sea-level rise predictions

Did you know?

Surface Water Drainage is drained by gravity from land onto the beach. As beach levels increase, this will become increasingly problematic due to beach levels Figure 12: Formby dune erosion being higher than the outfall levels.

Formby Dunes (11a 9) Action Plan as adopted 2010 – progress indicated in final column

ACTION PLAN Action Action Action Description, Outcome Progress to date Ref (to be approved)

1. Studies for policy area 1.1 Consider the need for compensatory habitat due to Informs actions. We will support Natural England where possible when they undertake this the squeeze of the dunes against built assets work restricting rollback and, if necessary, to identify compensatory habitat sites, working with the RHCP. 2. Studies for Policy Units:

3. Strategy 3.1 Develop and adopt long term dune management Sustainable Management. The Sefton Coast Management Plan is being reviewed and updated – due adaptation strategy to manage roll back of the 2016 dunes, maintaining their value as a natural defence and the environmental value. 4. Scheme Work 4.1 To be defined by dune management and Actions identified in Long Term Plan. Follows on from the review of the Sefton Coast Management Plan adaptation strategy. 5. Monitoring (Data 5.1 Undertake beach and dune monitoring in Data provided to CERMS provides The current programme (2011-2016) is being successfully delivered. Collection) conjunction with Cell 11 Regional Monitoring improved evidence base for future The application for the next five year programme (2016-21) has progressed Strategy to inform strategy and future SMP decision making through the Project Appraisal Board (September 2015) reviews. 5.2 Environmental monitoring of designated habitats within international conservation sites to provide baseline data for future Habitat Regulations Assessments 6. Asset Management 6.1 Beach and dune management including Maintenance undertaken to required We are providing technical advice for Land owners where required. management of public access. standards. 7. Communication 7.1 Consult key stakeholders and general public Public participation. Consultation on the Sefton Coast Management Plan due 2016 during dune management and adaptation strategy development. 7.2 Monitoring and management of Action Plans by NWNWCG reports on progress An annual report has been submitted to DEFRA NWNWCG to confirm SMP policies are put into practice.

8. Interface with Planning and 8.1 Advise local Planning Authority about SMP Coastal flood risks considered in land The Local Plan will undergo an Examination in Public in Land Management policies and flood and erosion risks so they can be use plans. November/December 2015. accounted for in the next revisions of land use The Coastal Change Management Area has been informed by the SMP plans in order to help manage residual risks from policies and information. flooding and erosion. Tidal flood risk has been considered within the Local Plan as part of flood risk from all sources. 8.2 Advise local Planning Authority about SMP Coastal flood risks considered in Planning applications are reviewed based on both coastal erosion and flood policies and flood and erosion risks so they can planning decisions. risk from all sources. take due account in planning decisions and aim to reduce the need to manage flood risk in future.

9. Emergency Response 9.1 Development, monitoring and review of Coastal flood risks considered in Following on from the winter of 2013/14 our response to high tide events was emergency response plans to prepare for over emergency plans. reviewed and amended with a High Tide Response Group being established design standard events. along with operating guidelines. 10. Adaptation/Resilience 10.1 See item 3.1, 12.1 – 12.5.

12.2 Investigate options for allowing the dunes to roll- Sustainable Management. Follows on from the review of the Sefton Coast Management Plan back naturally, while managing impacts on habitats and species. 12.3 Undertake a more detailed Habitats Regulations Sustainable Management. Follows on from the review of the Sefton Coast Management Plan Assessment for the adaptation strategy for this policy area.

12.4 Seek opportunities for habitat enhancements Sustainable Management. Follows on from the review of the Sefton Coast Management Plan during strategy development as part of flood/erosion risk management works e.g. consider sand fencing and grazing and scrub/weed control within the designated conservation sites, where and as appropriate. 12.5 Ongoing monitoring of erosion and document or Mitigation of losses. Follows on from the review of the Sefton Coast Management Plan record historic environment features as they become exposed. NB Activities from SMP will be carried forward into medium term plans and carried out on a priority basis, subject to funding and approval. n/a = activity is part of authorities general duties, not funded through flood and erosion risk management routes. EA = Environment Agency; LO = land owners; NE = Natural England; NWNWCG = North West and North Wales Coastal Group; RHCP = regional Habitat creation Programme; SC = Sefton Council.Programme; SC = Sefton Council. Table 7: Formby Dunes action plan

Figure 13: Map showing conceptual model for Formby area

6.0 Southport Area Summary

6.1 Baseline Information

Total length: 6.3km Defended length: 6.3km Concrete Sea Wall: 6.3km Saltmarsh: 2.8km

6.2 Site overview

Southport was built on reclaimed land that was once within the Ribble estuary. Hotels were built close to the sea and in 1835 a promenade and sea wall were built to protect property. These defences were originally constructed over a length approximately 500 metres south west of the current Pier and then extended roughly the same distance to the north east of the Pier, but had to be re-built many times after destructive storms.

The Marine Lake of 1887 did not extend beyond the Pier (constructed in 1860) but was such a success that a further lake and park were joined in 1895. In the 1960s the lake was again extended north to Fairway. Subsequently the Marine Drive was then extended north to Crossens in stages, on top of an embankment enclosing the extended Marine Lake and on sea embankments around the edges of Marshside Marsh, in the process reclaiming land for agricultural purposes.

From 200 metres south west of the Esplanade roundabout, to the roundabout at Weld Road the frontage was reclaimed from the foreshore in 1975 and formed the last link in the coastal road route that provided a dual function of formal promenade and vehicular by-pass for through traffic around the busy centre of Southport. Prior to 1975 coastal defence across the frontage had been provided by sand dunes and foreshore.

Until 1998, the central part of Marine Drive was still at its original low level and was frequently closed during periods of high tides. Flooding during severe storm surges damaged the road and funfair. A new sea wall and promenade was completed in 1998 and removed the need for road closures and facilitated the re-development of the seafront. Further stages of seawall reconstruction where completed from the Pier to Fairways roundabout in 2000 and between Weld Road and the Esplanade roundabout in 2001.

The whole of this length is now fronted by embankments built for land reclamation, highway construction and protection of recreational and commercial development. There have been no amendments to coastal defence arrangements since 2001.

Up until 2007 car parking on the beach was allowed across the upper foreshore between Weld Rd and the Pier. Since 2008 this practice has only been allowed between the Esplanade roundabout and the Pier.

6.3 Current (SMP2) Policy (adopted 2010)

The long term vision for the areas at the mouth of the estuary, Southport to the south and Lytham to the north, is to continue to manage risks to the towns and their associated facilities, but achieving this as far as possible through maintaining the naturally functioning systems with minimal interventions. The nature of these systems suggests that this approach can be justified on social, economic and environmental grounds. Within the Ribble and Douglas estuaries the long term plan is to establish a balance between protection of property, key infrastructure and industries, while creating more accommodation space where possible within the estuary systems. Consequently the recommended plan is for many existing flood defences to be maintained, but opportunities for managed realignment of present defences lines will be investigated.

Figure 14: Land reclamation

This may result in some loss of properties and agricultural land but this is balanced against reducing flood levels to larger communities and the need to provide compensatory natural habitats in the long term.

6.4 Policy and Approach (from 2010)

Location (Policy 2010-2030 2030-2060 2060-2110 Unit) 1.1 Weld Road to Hold the Line – Hold the Line – Hold the Line – Fairways Manage coastal flood Manage coastal flood Manage coastal flood (Southport) and erosion risk and erosion risk and erosion risk to Southport & to Southport & to Southport & associated facilities - associated facilities - associated facilities - Maintain defences as Maintain defences as Maintain defences as required. required. required. 1.2 Fairways to Hold the Line – Hold the Line – Hold the Line – Crossens Manage coastal flood Manage coastal flood Manage coastal flood Pumping Station and erosion risk and erosion risk and erosion risk to Southport & to Southport & to Southport & associated facilities - associated facilities - associated facilities - Maintain defences as Maintain defences as Maintain defences as required. Future required. required. plans would need to establish whether the defences should be along the line of Marine Drive or behind the marshes. Table 8: SMP policy Southport area

6.5 Key assumptions made during development

• Changes to the low water channels have a major control on the estuary processes and defence management in the estuary. It has been assumed that the position of these channels will continue to influence patterns of accretion and erosion in the future. • Predicted changes in rainfall patterns with future climate change may increase river flows which may in turn affect river channel meandering and siltation rates. • The supply of sediment to the estuary will continue and will allow the estuary to accrete vertically in line with sea level rise. This assumption is consistent with the past history of the estuary which has shown accretion. In the long term there is uncertainty over the balance between sediment supply and sea level rise. It has been assumed that supply will continue to allow vertical accretion within the estuary although the horizontal expansion of marsh habitats may have decreased or even cease. If sediment supply were not to keep pace with sea level rise in the long term then roll back of the estuary could occur, which would be expected to lead to coastal squeeze in locations where the high water mark abuts the defences. • The contamination risks are uncertain; therefore future studies will be required to address these uncertainties. • Management of defences in the outer estuary will be closely linked with the management of the adjacent open coast frontages due to shared flood risk issues and sediment supply. • The long term flood risk management policy for this estuary, as with others in the North West may change if proposals for tidal power barrages are progressed. • The key uncertainty concerns the detailed alignment of future set-back defences and the implications of this managed realignment on coastal processes in the Ribble Estuary.

Potential areas of realignment along the estuary will need to be carefully considered after exploring the influence on changes to tidal propagation. • Economic justification needs to be examined in more detail at strategy level and opportunities for co-funding need to be investigated. • The SMP policies will be subject to review if sea level rise predictions are changed.

6.6 Summary of behaviour

The Pier structure at Southport extends out approximately 1km across the shoreline but, apart from localised influences on the remnants of historic channel movement, it has a limited effect on process behaviour. Predominant waves approach from directions W to NW. The highest waves are from the west. The frontage is a sediment sink with the primary sources being the intertidal areas north of Formby, or the Irish Sea bed.

This section of frontage is a zone of net accretion, represented by a growth in upper beach volumes. This has created low energy environments inshore, which has led to the development of a vegetated area of foreshore, known as Smith’s Slack, along the backshore section. This results in the sand dunes behind being protected from exposure to waves but also cut off from any supply of fresh sand, as such they are becoming a more stable rather than dynamic feature. We would expect this behaviour to continue in the short term (up to 20 years).

The area of saltmarsh at Crossens is gradually spreading in a south westerly direction across the frontage. At the southern end Smith’s Slack has migrated northerly to the southerly boundary of the “new” defences, with intermittent growth only in front of the defences.

Between Esplanade and the Pier vegetation of the beach is inhibited by the car parking across this part of the frontage.

Adjacent to the sluice gates (used for emptying and refilling the marine lake) there is a tendency for beach levels to be locally lower due to the regular flow of water from the gates. The wing walls of the sluice gates structure on the seaward side are in poor condition, possibly due to differential settlement as they are not piled whilst the main structure is. The design of the seawall allowed for the lower beach levels here by having a deeper toe beam to avoid it being undermined.

The flow from the lake and the pier have in the past appeared to anchor the Boghole Channel to that location but as this channel diminishes in size it also appears to be changing in location and moving away from the pier.

During the extreme events over winter 2013/14 there was overtopping along a substantial length of this frontage requiring the road to be closed from Weld Road through to Fairways. Given that the design standard for the structure is 1 in 20 the structure performed as expected and did not suffer any damage. As a result of this event the procedures for closing the highway for predicted high tides has been reviewed and updated. The areas of saltmarsh and green beach appeared to be quite resilient to these events.

Maintenance along the length from Weld Road to Fairways is minor, mainly joint filling and some concrete repair. Further north the embankment has a tendency to get plant growth in the joints which is removed when necessary. Although the older length of defence going from Fairways to Crossens is in a much poorer condition and of a lighter construction the saltmarsh in front of it removes the majority of the wave energy.

The old compound for sand winning has had the majority of the remedial works undertaken by the operator. This has involved removal of material back to the level of the surrounding saltmarsh for

two thirds of the site with the remaining third retained for potential use by the RSPB. There is no indication that there is any concrete embankment protecting the road if this final third were removed.

A significant influence on the development of this area has been the training of the Ribble to the north side of the estuary. Given this it will be important to monitor the condition of the training walls at regular (5 yearly) intervals.

6.7 Risk Assessment

• Overtopping of artificial defences causing flooding of the hinterland, • Breaching of artificial coastal defences, causing setback and erosion of the shoreline • Failure of the wing walls on the sluice gates causing flooding of the hinterland

The primary consequences of this behaviour are:

• Damage to and/or loss of property and infrastructure • Damage to environmental habitats. • Closure of the road

Southport Overall Risk Rating SMP2 Overall Probability Consequenc Policy Unit Section of Frontage Exposure Risk Index e Index (11b) Rating 1.1 Weld Rd to Fairways Medium Medium Medium/High Medium Fairways to Crossens 1.2 Medium Medium Medium/High Medium Pumping Station (part) Table 9: Risk rating Southport area

6.7.1 What would this risk look like?

Overtopping of the defences fronting Southport can look dramatic but is unlikely to cause damage to property. The main issues will be disruption to traffic and the potential hazards to traffic and pedestrians caused by overtopping. Overtopping will tend to occur first at the sluice gates where the slightly lower beach level and vertical face of the structure combine to create overtopping.

Extreme events may damage the defences to the north of Fairways but this is unlikely to result in a failure over one set of high tides, it is more likely to create damage that if left will get worse during the next storm event.

Failure of the wing walls at the sluice gates could result in undermining and closure of the road and release of contaminated material although this is contained behind a sheet pile wall that supports the wave wall units.

6.8 Uncertainties & Issues

The following uncertainties have arisen from the data monitoring programme and analysis of the data collected:

• Quantities of sediment being moved into and within the estuary. • Changes in lower foreshore conditions between marsh edge and channels • Changes in the area of the saltmarsh • Movement and evolution of the Bog Hole Channel • Movement of the main channel in the Ribble Estuary • Condition of the training walls in the Ribble • Impacts on the scale and rate of change of sea level

6.9 Planned actions from the SMP

• Review and update of the Sefton Coast Management Plan • Implementation of Hesketh outer Marsh scheme

6.10 Recommendations for additional actions

• Repair wing walls • Monitor the training walls in the Ribble • Continue with High tide response group to review closure of roads and carparks

6.11 Potential influences on SMP policies

• Changes in sea level rise predictions

Ribble Estuary (11b 1) - Action Plan as adopted 2010 – progress indicated in final column

ACTION PLAN Action Action Action Description, Outcome Progress to date Ref (to be approved)

1. Studies for policy area 1.1 Undertake estuary wide studies to investigate Extent of managed realignment area Planned / Programmed various Managed Realignment opportunities in confirmed, habitat gains by type and medium to long term and develop plans to preferred technical approach to implement where practicable to create a more realignment assessed. Outputs from sustainable defence alignment. Include coastal study linked to RHCP. processes and habitats study; stakeholder consultation, more detailed economic appraisal; consideration of options for adapting paths and rights of way to coastal change. Assess needs for intervention to manage land drainage in areas where saltmarsh accretion causes problems at outfalls. 2. Studies for Policy Units: Develop a Beach management plan for Southport Sustainable Management. This action will be reviewed following on from the completion of the Sefton PU 1.1 2.1 Frontage to maintain amenity value of the beach in Coast Management Plan. the most cost effective and sustainable manner. PU 1.2 2.2 Assess tidal flood risks for Marshside & Crossens Sustainable Management. Delayed marsh, including revised Sea Level Rise estimates and consider coastal adaptation requirements. PU 1.3 2.3 Consider undertaking studies to assess the flood Management of flood risk. Hesketh Out Marsh East - planned to be delivered 2014/15. Planning risk to Banks and potential for reinstating old sea permission approved. wall as a secondary line of defence, together with medium to longer term options for managed realignment. PU 1.5 2.4 Seek opportunities to build / improve secondary Extent of managed realignment area Hesketh Out Marsh East - planned to be delivered 2014/15. Planning defences at Hesketh Outmarsh East to North East confirmed, habitat gains by type and permission approved. corner of Hesketh Outmarsh to achieve a more preferred technical approach to sustainable defence alignment and facilitate habitat realignment assessed. creation.

3. Strategy 3.1 Develop estuary flood risk management strategy Strategy approved by EA. Planned / Programmed taking into account the estuary wide and policy unit studies above to provide more detailed proposals on approaches to the delivery of policy across the estuary and a programme of actions to deliver it. The estuary strategy needs to link to the open coast strategy being developed between Anchorsholme and Naze Point. 4. Scheme Work 4.1 To be defined by strategy Actions identified in Long Term Plan.

5. Monitoring (Data 5.1 Undertake estuary, coastal defence and dune asset Data provided to CERMS provides The current programme (2011-2016) is being successfully delivered. Collection) monitoring in conjunction with Cell 11 Regional improved The application for the next five year programme (2016-21) has progressed Monitoring Strategy to inform strategy and future evidence base for future decision through the Project Appraisal Board (September 2015) SMP reviews. making

5.2 Environmental monitoring of designated habitats within international conservation sites to provide baseline data for future Habitat Regulations Assessments 6. Asset Management 6.1 Maintenance of defences and beach and dune Maintenance undertaken to required Condition of the asset: management including management of public standards. Is it getting worse? Yes/No access Are we spending more? Yes/No 7. Communication 7.1 Undertake consultation with key stakeholders and Participative planning Consultation on the Sefton Coast Management Plan due 2016 general public during strategy development 7.2 Monitoring and management of Action Plans by NWNWCG reports on progress An annual report has been submitted to DEFRA the NWNWCG to confirm SMP policies are put into practice 8. Interface with Planning and 8.1 Advise local Planning Authority about SMP Coastal flood risks considered in land The Local Plan will undergo an Examination in Public in Land Management policies and flood and erosion risks so they can be use plans. November/December 2015. The Coastal Change Management Area has accounted for in the next revisions of land use been informed by the SMP policies and information. Tidal flood risk has plans in order to help manage residual risks from been considered within the Local Plan as part of flood risk from all sources. flooding and erosion.

8.2 Advise local Planning Authority about SMP Coastal flood risks considered in Planning applications are reviewed based on both coastal erosion and flood policies and flood and erosion risks so they can planning decisions. risk from all sources. take due account in planning decisions and aim to reduce the need to manage flood risk in future.

9. Emergency Response 9.1 Development, monitoring and review of Coastal flood risks considered in Following on from the winter of 2013/14 our response to high tide events emergency response plans to prepare for over emergency plans. was reviewed and amended with a High Tide Response Group being design standard events. established along with operating guidelines. 10. Adaptation/Resilience 10.1 Investigations for recommended for managed realignment see items 1.1, 2.3, 2.5. & 11.1.

10.2 Monitor proposals for tidal power embayment’s Integrated approach to shoreline and barrages and build into next review of management. Shoreline Management Plan.

11. Flood Forecasting and 11.1 Continue to improve flood risk maps and Improved flood warnings and risk Warning inundation modelling, particularly in areas where mapping, raising awareness of coastal there are dunes and promenades and areas risks. benefiting from these defences are not currently shown. 12. Habitat Creation and 12.1 Monitor progress with dune management in PU Improved evidence base for decision environmental mitigation 1.20 & 1.21, and habitat creation in areas of making. Managed Realignment. 12.2 Investigate and quantify habitat losses and creation Meet legal requirement potential to feed into the RHCP and subsequently identify and secure intertidal habitat through the RHCP, if necessary to compensate for any habitat losses in the long-term. NB. Activities from SMP will be carried forward into medium term plans and carried out on a priority basis, subject to funding and approval n/a = activity is part of authorities general duties, not funded through flood and erosion risk management routes. EA = Environment Agency; FBC = Fylde Borough Council; LO – land owners; NE = Natural England; NWNWCG = North West and North Wales Coastal Group; PDWA = Preston and District Wildfowlers Association; RHCP = Regional Habitat creation Programme; SC = Sefton Council, WLBC = West Lancashire Borough Council Table 10: Action plan Southport area

Figure 15: Map showing conceptual model for Southport

7.0 West Lancashire Area Summary

7.1 Baseline Information

Total length: 12.1km Defended length: 12.1km Earth Saltmarsh: 12.1km Embankment: 12.1km

7.2 Site overview

This section of frontage is between the River Crossens and River Douglas, tributaries of the Ribble Estuary. Historically low water channels meandered across the Ribble estuary. In the 1840s training wall were built to fix the position of the channels. This allowed saltmarsh to grow on either side of the main channel. From the mid 1800’s to the 1980s banks were built to reclaim some of this saltmarsh for agricultural land. Around 2005 a joint project between RSPB, the Environment Agency, Lancaster City Council and Lancashire Rural Recovery Action Plan returned some of the reclaimed land back to saltmarsh. This involved setting back primary defence arrangements to historical positions, creating new embankments and breaching sections of the outer embankment.

The whole of this section is defended by earth embankments, of different ages and forms.

In the past ten years the following work has been carried out:

• Improvement works to Hesketh Marsh Secondary Embankment • Realignment of Hesketh Outer Marsh Embankment (West) • Breaching of original section Hesketh Outer Marsh Embankment (West) • Design of scheme for Hesketh Outer Marsh (East) with a view to breaching the embankment in 2017

7.3 Current (SMP2) Policy

Within the Ribble and Douglas estuaries the long term plan is to establish a balance between protection of property, key infrastructure and industries, while creating more accommodation space where possible within the estuary systems. Consequently the recommended plan is for many existing flood defences to be maintained, but opportunities for managed realignment of present defence lines will be investigated. This may result in some loss of properties and agricultural land but this is balanced against reducing flood levels to larger communities and the need to provide compensatory natural habitats in the long term.

7.4 Policy and Approach (from 2010)

Location (Policy 2010-2030 2030-2060 2060-2110 Unit) 1.3 Crossens Hold the Line – Hold the Line – Managed Pumping Manage flood risk by Manage flood risk by Realignment – Station to Hesketh maintaining existing maintaining existing Seek opportunities to Out Marsh West defences to an defences to an realign by building / (Hundred adequate standard. adequate standard. improving set back End Gutter) Undertake studies to defences where investigate Managed practicable. Realignment opportunities in the long term and implement where practicable. 1.4 Hesketh Out Hold the Line – Hold the Line – Managed Marsh West Manage flood risk by Manage flood risk by Realignment – maintaining existing maintaining existing Seek opportunities to defences landward of defences to an realign by building / Hesketh Out Marsh adequate standard. improving set back to an adequate Undertake studies to defences where standard. investigate Managed practicable. Realignment opportunities in the long term and implement where practicable. 1.5 Hesketh Out Managed Hold the Line – Hold the Line – Marsh East Realignment – Manage flood risk by Manage flood risk by Seek opportunities to maintaining new set maintaining build / improve back defences to an realigned defences to secondary defences. adequate standard. an adequate standard. Table 11: SMP policy West Lancashire area

7.5 Key assumptions made during development

• Contamination risks are uncertain; therefore future studies will be required to address these uncertainties. • Management of defences in the outer estuary will be closely linked with the management of the adjacent open coast frontages due to shared flood risk issues and sediment supply. • The long term flood risk management policy for this estuary, as with others in the North West may change if proposals for tidal power barrages are progressed. • The key uncertainty concerns the detailed alignment of future set-back defences and the implications of this managed realignment on coastal processes in the Ribble Estuary. Potential areas of realignment along the estuary will need to be carefully considered after exploring the influence on changes to tidal propagation. • Economic justification needs to be examined in more detail at strategy level and opportunities for co-funding need to be investigated. • The SMP policies will be subject to review if sea level rise predictions are changed.

7.6 Summary of behaviour

Across this section of shoreline waves generated by winds blowing across the Irish Sea are intercepted by the sand banks in the outer Ribble estuary and the saltmarsh in front of the earth embankments. Fine sediments are moved into this section of frontage due to, primarily, tidal forces. These features reduce the impact of hydrodynamic forces on this section.

Data collected between the River Crossens and Hundred End Gutter shows that the saltmarsh is generally stable in elevation (at or about mean high water spring tide level), with little evidence to support significant growth.

7.7 Risk Assessment

• Overtopping or breaching of artificial defences causing flooding of the hinterland

The primary consequences of this behaviour are:

• Damage to agricultural land, property and infrastructure • Damage to environmental habitats.

West Lancashire Overall Risk Rating SMP2 Overall Probability Consequence Policy Unit Section of Frontage Exposure Risk Index Index (11b) Rating Fairways to Crossens 1.2 Medium Medium Medium/High Medium Pumping Station (part) Crossens Pumping Station to Medium 1.3 Hesketh Out Marsh West Low High Medium (Hundred End Gutter) 1.4 Hesketh Outer Marsh West Medium Low Medium Low 1.5 Hesketh Outer Marsh East Medium Low Medium Low Table 12: Risk rating West Lancashire

7.7.1 What would this risk look like?

Given the location within the estuary and the protection afforded by the saltmarsh wave energy reaching the embankments would be limited so any overtopping would be limited in its scale. If a breach of a defence occurred this could result in substantial quantities of water entering through the breach and cause damage to the area concerned. The last time this occurred was in the 1970’s when the embankments were not so well maintained and there was much less saltmarsh, the result was a number of low lying properties experiencing internal flooding in the Harrogate Way area.

7.8 Uncertainties & Issues

The following uncertainties have arisen from the data monitoring programme and analysis of the data collected: • Quantities of sediment being moved into and within the estuary. • Changes in lower foreshore conditions between marsh edge and channels • Changes in the area of the saltmarsh • Movement and evolution of the Bog Hole Channel • Movement of the main channel in the Ribble Estuary • Condition of the training walls in the Ribble • Impacts on the scale and rate of change of sea level

7.9 Planned actions from the SMP

• Review and update of the Sefton Coast Management Plan • Implementation of Hesketh outer Marsh scheme

7.10 Recommendations for additional actions

• Monitor the training walls in the Ribble

7.11 Potential influences on SMP policies

• Changes in sea level rise predictions

Figure 16: Offshore wave height Formby

Figure 17: Map showing conceptual model for West Lancashire