Erosion management in Inch beach, South West Ireland

Ocean & Coastal Management 54 (2011) 930e942

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Erosion management in Inch beach, South West Ireland J. Gault a, A.M. O’Hagan b, *, V. Cummins a, J. Murphy b, T. Vial b a b

Coastal and Marine Research Centre (CMRC), Environmental Research Institute, University College Cork, Naval Base e Haulbowline, Cobh, Co. Cork, Ireland Hydraulics and Maritime Research Centre (HMRC), Youngline Building, Pouladuff Road, University College Cork, Co. Cork, Ireland

a r t i c l e i n f o

a b s t r a c t

Article history: Available online 30 May 2011

This paper describes the influences on operational management of erosion at Inch beach, Co. Kerry on the south west coast of Ireland with specific reference to the CONSCIENCE Frame of Reference for erosion management and the key concepts defined under the EUROSION project. It provides an insight of the wave climate and quantifies contemporary erosion patterns through a combination of field analysis and modelling. An attempt is made to assess the response of the coastline to storms with varied return periods and to place current change in an historical context. The reasons for the lack of application of these key concepts are explored in combination with the applicability of the Frame of Reference to the management of Inch Strand. This paper describes the outcomes of attempting to apply this Frame of Reference at Inch Strand and the affect that national coastal policy, or lack thereof, has on the utilisation of internationally recognised erosion management concepts by local stakeholders with responsibility for eroding coastlines. The paper is of significance not only to an Irish audience, but also the wider international community who may face similar challenges in managing their coastal resources. Ó 2011 Elsevier Ltd. All rights reserved.

1. Introduction 1.1. Research context Inch Strand was one of six representative pilot sites across Europe identified by the FP6 funded Concepts and Science for Coastal Erosion Management (CONSCIENCE) Project e the other sites being in the Netherlands (Dutch Coast), Poland (Hel Peninsula), Romania (Danube Delta), Spain (Costa Brava) and the United Kingdom (Pevensey Bay) respectively. By working with local stakeholders it was hoped to assess the potential application and assess the relevance with respect to operational coastal management on eroding coastlines of four key concepts, as developed as part of the EU 5th Framework EUROSION Project (European Commission, 2004) and described below: To assist with this process a Frame of Reference for implementing the coastal erosion management policy, after van Koningsveld et al. (2003), was utilised in order to frame these concepts in a policy context and to make it possible to assess the effects of any policy or change of policy in an iterative manner. Therefore the Frame of Reference is divided into four fundamental steps in policy making (see below and Fig. 1):

* Corresponding author. Tel.: þ353 21 4250015; fax: þ353 21 4321003. E-mail address: [email protected] (A.M. O’Hagan). 0964-5691/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.ocecoaman.2011.05.005

1. Quantitative state concept: a means of quantifying the problem in hand. Coastal state indicators (CSI) are effective at this first stage as these are specific physical parameters that can influence decision making behaviour / policy) 2. Benchmarking process: a means of assessing whether or not action is required and for this stage CSI can be compared to some agreed threshold value. 3. Intervention procedure: A detailed definition of what action would be required if the benchmark threshold (above) is exceeded. 4. Evaluation procedure: Impact assessment of the action taken. If the action was not successful then it may be necessary to revise the original strategic / tactical objectives and hence the inclusion of feedback loops (Marchand, 2010). 1.2. Site description Inch beach is a large barrier-dune system located in Dingle Bay, County Kerry in the South West of Ireland (Fig. 2). It is characterised by its long (c.5.5 km) expanse of sandy beach (Inch Strand) backed by an extensive dune-system with the main dune line dating back to at least the 200 years (Wintle et al., 1998), its expansive ebb tide delta at the southern (distal) point and the fast flowing channel between it and the adjacent barrier beach at Rosbehy. Dingle Bay is mesotidal, with a spring tidal range of c.4 m, and the tide races through the channel to fill and drain the large inter-tidal area around the moraine at Cromane in the back estuary that forms Castlemaine Harbour.

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Eurosion key concepts for erosion management Coastal resilience: the inherent ability of the coast to accommodate changes induced by sea level rise, extreme events and occasional human impacts, whilst maintaining the functions fulfilled by the coastal system in the longer term. Strategic sediment reservoirs: supplies of sediment of ‘appropriate’ characteristics that are available for replenishment of the coastal zone, either temporarily (to compensate for losses due to extreme storms) or in the long term (at least 100 years). They can be identified offshore, in the coastal zone (both above and below low water) and in the hinterland. Favourable sediment status: the situation where the availability of coastal sediments support the objective of promoting coastal resilience in general and of preserving dynamic coastlines in particular. Coastal sediment cell: a coastal compartment that contains a complete cycle of sedimentation including sources, transport paths, and sinks. The cell boundaries delineate the geographical area within which the budget of sediment is determined, providing the framework for the quantitative analysis of coastal erosion and accretion. In this respect, coastal sediment cells constitute the most appropriate units for achieving the objective of favourable sediment status and hence coastal resilience

Inch Strand has a dissipative shore face and due to its southwesterly facing Atlantic aspect it is often subjected to high energy storm conditions with significant wave heights of over 6 m not uncommon. Depending on their duration and strength this can cause either short-term seasonal erosion of the dune face which recovers relatively quickly (days e weeks) or in extreme conditions can cause complete removal of the fore-dunes and depending on the scale of retreat, recovery occurs over a much longer period (months e years) (Orford et al., 1999). 1.3. Management For the majority of the year Inch Strand is utilised on a regular basis by the local population and the occasional off-season tourists

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but in the Summer season (JuneeSeptember) these numbers are augmented by the large number of coach parties who visit the Strand. Moreover these coach tours access the site and the neighbouring tourism hotspots, such as Dingle to the west, using a narrow coastal arterial road which is underpinned by a significant coastal protection scheme at the Northern end of Inch. Kerry County Council are the, de facto, managers of Inch Strand and in response to safety concerns and the potentially catastrophic impact of closure of one of the main tourism routes in Ireland they decided to construct these sea defences in 2005 (O’Connor et al., 2009) (Fig. 3). However, it should be noted that this construction was not in response to analysis of routine monitoring but moreover in response to a report in early 2000 on road slippages around Inch commissioned by the local authority, Kerry County Council. The current absence of any national coastal management policy, the associated lack of an agreed monitoring approach coupled with antiquated foreshore legislation, makes it extremely difficult for local coastal managers (primary stakeholders) to provide a coherent response to coastal erosion never mind adhere to the principles of Integrated Coastal Zone Management (ICZM) contained in the EC Recommendation on the implementation of ICZM (2002/413/EC) (European Parliament and Council, 2002). In the context of the Frame of Reference for implementing coastal erosion management policy (Fig. 1), the Strategic and Operational Management Objectives are to provide for proper planning and sustainable development and to protect infrastructure in support of tourism respectively. This paper describes the outcomes of attempting to apply this Frame of Reference at Inch Strand and the affect that national coastal policy, or lack thereof, has on the utilisation of internationally recognised erosion management concepts by local stakeholders with responsibility for eroding coastlines. 2. Assessing coastal processes at inch The CONSCIENCE project was not really intended to support large-scale data collection, more to use the data that was available to develop and test models and to assess the applicability of the Frame of Reference for erosion management. However as there is no longterm monitoring programme in place at Inch, and therefore little data, a decision was taken to undertake a limited field campaign to provide key data such as sediment type, coastline storm response,

Strategic objective

Operational objective

1. Quantitative State Concept

2. Benchmarking Procedure

CSI • Monitoring • System knowledge • Measurement • Modelling

Desired state

3. Intervention procedure

Current state

Fig. 1. Generic Frame of Reference for Coastal Management [2].

4. Evaluation procedure

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Fig. 2. Geographical location of Inch Strand, Dingle Bay, Co. Kerry, Ireland.

beach topography and wave climate. This was achieved using a combination of field surveys and modelling approaches including: 1. Collection of in situ wave data using autonomous wave gauges 2. Short-term beach profiling using a differential Geographical Positioning System (dGPS) 3. Numerical analysis of long-term wave modelling output (WAM) 4. Application of modelling software, primarily wave modelling (MIKE21) but also an attempt to include some sediment transport modelling software (LITPACK) 2.1. In situ wave data collection Two Valeport MIDAS wave gauges were initially set-up for a planned one month period in November 2007 in order to get in situ data to get an insight into wave conditions during storm conditions, for comparison with coincident beach profiling surveys and to provide calibration data for the wave modelling software. The gauges were deployed at two positions off Inch Strand just below the 10 m contour in 11.6 m of water and in 10.6 m respectively.

During this short period there were two significant storms with Hs values of 5.5 m being recorded during the second storm on the 9th December 2007. Given this and the fact that the gauges were deployed in relatively shallow water it was unsurprising that when the gauges were checked at the next weather window in late December that they had moved up to 150 m from their initial positions. In addition, recovery of the gauges had to be postponed as they were buried into the substrate. The Southern gauge was finally recovered by divers in February 2008 but the Northern gauge was never recovered and therefore only one set of wave data was available for use. Significant wave heights as measured (see Section 2.3) reveal that there were a number of large storms during the recording period. The analysis showed that the storms that occurred between December 1ste9th had 1.4 and 20-year return periods. Two other storms that occurred during the monitoring period but not during the Valeport deployment were found to have return periods of 6 and 15 years (March 3rde10th). The Valeport also enabled the magnitude of storm surge during the storm events to be determined and it was found that there was no significant storm surge apart from the December storms as indicated above where

Fig. 3. Photograph of the coastal defences at the Northern End of Inch Strand, Co. Kerry, Ireland.

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Fig. 4. Maps showing profile lines and sediment sampling positions on Inch Strand, Co. Kerry, Ireland.

values of 0.68 m was measured. It was estimated that the maximum surge level for the March storms was of the order of 1 m. 2.2. Beach profiling and sediment sampling Twenty-six profiles were established on Inch Strand (Fig. 4) and shore normal profiling was carried after storm periods over a fivemonth period in Winter 2007 / Spring 2008 using a Trimble ProXH dGPS.

In general the beach has a low gradient of the order of 1:84 and this did not change significantly over the course of the study. The analysis of the dune-line position revealed that the fore-dune receded distances of several metres in a period of days as a result of elevated wave energy levels (Fig. 5). There were two phases of significant erosion corresponding to the storm periods in December 2007 and March 2008. The December storms caused an average recession of 11 m whilst the value was 7 m for March. However it is worth noting that in late Spring / early Summer the fore-dunes had

0

dune recession (m)

-5

-10

-15

-20

-25

-30 1

2

3

4

5

6

7

8

9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Profile No Baseline 29/11/2007

06/12/2007

12/12/2007

17/12/2007

08/02/2008

12/03/2008

21/03/2008

24/04/2008

Fig. 5. Variation in coastline position at Inch Strand between Dec 07 e April 2008.

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Table 1 Data input for extreme wave analysis. Mean Wave Direction of propagation (degrees)

North

South

210

240

West

300

330

Data points Occurrence [%] Wave height-threshold [m] Number of storms selected (partial duration series) Number of storms selected (annual maximum series)

6023 5.2 4.0 84 40

3631 3.1 4.0 80 40

8274 8.0 5.6 78 40

18810 16.1 6.9 79 40

29820 25.5 8.3 83 40

29617 25.3 8.2 79 40

17250 14.8 6.2 79 40

stabilised and early signs of accretion were recorded. This suggests that whilst the changes were marked, they formed part of an annual cycle of erosion and accretion and the storms recorded whilst severe, were not intense enough to cause the scale of changes (>100 m) that have been historically recorded at the site (Orford et al., 1999). In excess of 35 sediment samples were taken at representative points along and across Inch beach - the particle size in shown in microns (Fig. 4). Sample locations approximately corresponded with a number of the profile lines and were taken at levels related to the HAT, MWL and MLWS. These were subsequently analysed using a Malvern Mastersizer 2000 Laser Granulometer and sorted according to (Folk, 1954). The analysis showed that the mean particle size is relatively constant along the beach (average D50 of 240 mm) and that the gradation can be categorised as being moderately to well sorted. It was also found that there were no significant changes in sediment characteristics after the Winter season and that the results matched with sediment sieving carried out in 1993 (Orford et al., 1999).

2.3. Numerical analysis of long-term wave modelling output (WAM) A long-term dataset was readily available from a wave hindcast model run under the EU FP5 HIPOCAS (Hindcast of Dynamic Processes of Ocean and Coastal Areas of Europe) project in University College Cork (Vijaykumar et al., 2004). The WAM data were first sorted by direction, considering sections of 30 ; i.e. 15 either side of the mean direction reviewed. Ideally, the longer the duration of the existing data series is, the more reliable the predicted wave heights are for high return periods. The maximum return period predicted for any data sets should not exceed two to three times the period of data series in order to get consistent extreme wave heights (Thompson, 2002). As the WAM data are available for 40 years, the 100-year return period wave heights could be estimated with confidence. For each selected mean wave Table 2 Results of the partial duration series analysis (in bold) and the annual maximum series analysis. “A” stands for the slope of the trend line used to calculate the extreme wave heights and “B” gives the ordinate of this line. Segment Distribution function that fits the best the data Shape-parameter k

North South 210 240 West 300 330

W FT1 1.00 e 0.99 Correlation R2 0.99 A 1.24 Scale-parameter 1.14 B 4.02 Location-parameter 5.17 8.9 25-year return period significant wave height x25 [m] 8.8 9.8 50-year return period significant wave height x50 [m] 9.6 10.6 100-year return period significant wave height x100 [m] 10.4

W W 2.00 2.00 0.99 0.93 2.06 2.12 3.36 3.78 7.4 7.6 7.8 8.0 8.1 8.3

W FT1 1.21 e 0.99 0.95 1.40 1.09 5.56 6.60 9.9 10.0 10.5 10.8 11.1 11.6

W W 1.25 2.00 0.98 0.98 1.88 4.10 6.68 5.14 12.3 12.5 13.0 13.2 13.8 13.9

W W 1.25 2.00 0.99 0.98 1.97 4.27 8.12 6.48 14.0 14.2 14.8 14.9 15.6 15.6

W FT1 1.00 e 0.99 0.99 1.66 1.72 8.20 9.30 14.9 14.8 16.2 16.0 17.0 17.2

W W 1.5 2 0.99 0.97 1.62 2.77 6.05 5.36 10.0 10.3 10.5 10.8 11.0 11.3

direction, the 25-year and 50-year were also calculated. Both the partial duration and the annual maximum methods were used. For the partial duration series analysis, constant thresholds were chosen such that approximately 80 values were selected for each segment (see Table 1). This value corresponds to two times the number of years of record which matches the criteria defined by Thompson (2002). For the annual maximum series analysis, one storm was selected for each year. The selected storm characteristics were then compared with the common distributions functions in order to design the extreme wave heights. The shape parameters tested were 0.75, 0.85, 1.0, 1.1, 1.25, 1.5 and 2.0 for the Weibull distribution function and 2.5, 3.33, 5.0 and 10.0 for the Fisher-Tippett type II. Correlation coefficients R2 were calculated for each function in order to evaluate which distribution function fitted the selected wave heights best. Table 2, below, shows good correlation coefficients ranging from 0.93 to 0.99 which means that the selected distribution functions fit well the selected wave heights values. It can be seen that the partial duration series and the maximum annual series gave similar results. The highest difference of wave heights given by both methods is equal to 40 cm which represents only 3% of the corresponding wave height value. The 100-year return period wave heights calculated range from 8.1 m to 16.97 m depending on the mean wave direction of propagation. The highest extreme waves come from the mean wave directions 240 , 270 and 300 . For each of these mean wave directions, the calculated extreme wave values were then used for the numerical simulations of extreme events reaching Dingle bay. These are shown in Table 2 and graphically in Fig. 6. This analysis was subsequently used to provide boundary conditions for the numerical model in order to determine the wave climate at Inch beach. 2.4. Wave modelling and sediment transport modelling The DHI program MIKE21 SW (Danish Hydraulic Institute, 2004) was used to simulate the propagation of wind generated waves and swell into coastal areas around Inch. For this model the discretization of the equations in geographical and spectral space is performed using the cell-centred finite-volume method. The bathymetry and the mesh of the chosen model for Dingle Bay is shown in Fig. 7, noting that the unstructured triangular mesh has a higher level of refinement closer to the area of interest around Inch Strand. Along the offshore boundary of the model, it is assumed that the input-data is not varying and the following wave parameters have to be specified:    

Significant wave height Mean wave period Tz Mean wave direction Directional spreading index (directional standard deviation)

For the calibration of the model, wave and wind data from the M3 data buoy for Winter 2007 were used. Tide level variations were included in the calibration simulations and these were obtained

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Fig. 6. Extreme Wave Height Analysis for Dingle Bay, Co. Kerry.

from the Valeport measurements. Model output as extracted at the southern Valeport location was compared to the measured data for 15th November - 12th December period and good correlation was recorded as is shown in Fig. 8. With confidence that the model was correctly reproducing the wave conditions at Inch the inshore wave climate was determined by inputting the offshore wave climate data as is shown in Table 2. It was found that the resultant wave conditions offshore of Inch beach reduced in terms of Hs and propagated from a single directional band. The next stage of the analysis process involved examining the response of the beach using numerical models. The DHI developed

LITPACK software was used for this purpose and in particular the LITPROF module as it deals with cross-shore profile changes. The model is suitable for the northern part of Inch beach because longshore gradients are presumed to be small and the depth contours are more or less parallel to the coastline. The wave transformation across the profile is calculated by considering shoaling, refraction, bed friction and wave breaking. Transport rates are calculated by the utility program PRFTABL. Finally the bed level change is calculated by the continuity equation for sediment transport. The output from the profile surveys covered the upper shore down to approximately the mean low water mark. As LITPROF requires the

Fig. 7. MIKE21 Modelling Grids in the greater Dingle Bay Area.

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Fig. 8. Comparison of MIKE21 data with real-time data for Dingle Bay, Co. Kerry.

profile to extend to the closure depth the profiles were extrapolated using Admiralty charts. It was found in this case that LITPROF was not that suitable for understanding the behaviour of Inch as the model could not be calibrated properly against the field surveys. As can be seen from Table 3 the model tended to overestimate the erosion of the dunes by various amounts. In addition it showed that quite a substantial offshore bar is created and this could not be validated as field measurements did not extend below low water. This resulted in a decrease of the beach slope. The measurements generally do not show such a big change in the beach slope with more a parallel displacement measured during the surveys. It was not possible to obtain the same slope of the beach for the measured profiles and the simulated profiles but the simulated morphological changes were at least within the same range as those measured. It was concluded that, because of a lack of accurate profile data, LITPROF could not be used in this case as a predictive tool to determine the beach response to extreme storm events. Therefore the conditions that give rise to the dunes eroding in excess of 100 m could not be reliably tested. Thus this software cannot currently be used as a tool for the management of Inch beach. 2.5. Understanding of the key concepts From the structured interviews conducted with key stakeholders it was clear that the local coastal managers understood fully the key concepts, as defined under the EUROSION Project, were aware of this Project and its outcomes and would have been Table 3 Dune Erosion during Winter 2007 (measured/simulated - metres). Profile

1

8

14

20

26

29th November 6th December 12th December 17th December Factor of over-estimation

0/0 0/44 1/56 1/60 58

0/0 4/e 8/26 8/48 4.63

0/0 7/24 12/30 14/36 2.83

0/0 2/30 12/40 13/60 7.65

0/0 7.5/32 12/30 12/e 3.4

more than willing to include these in their operational management of Inch Strand (Mulder et al., 2009). Unfortunately, without the requisite data it is impossible to fully employ these concepts. For example, in order to pinpoint a strategic sediment reservoir or assess the true sediment status, an accurate bathymetry of the Dingle Bay area would be required and current published charts are based on surveys conducted in the mid nineteenth century. It is assumed that Dingle Bay is a closed sediment cell but this, whilst reasonable, is still only an assumption and there is no available research to unconditionally support this assumption. Therefore the desire for coastal managers, as primary stakeholders, to use the EUROSION concepts is currently frustrated by the paucity of data. It is the authors’ contention that this is a direct result of the lack of a monitoring programme due to the absence of a policy driver as discussed in more detail below.

3. Current national coastal policy framework 3.1. Legal framework Arguably one of the problems in addressing erosion management in a coherent manner is due to the antiquated legislation and the jurisdictional issues which have derived from this. Historically the Coast Protection Act, 1963 provided for the making and execution of coastal protection schemes and connected matters. The Draft Policy on Coastal Zone Management (Brady Shipman Martin, 1997) described the legislation as being “unwieldy to use and insufficient in scope” and as a result was, and is, in disuse (Department of Communications, Marine and Natural Resources, 2002). That Act tasked the Office of Public Works with carrying out protection schemes as, at that time, that was one of their key functions. Since then, responsibilities have transferred back and forth between various Government departments, and consequently it became more common in practice for coastal protection schemes to be carried out under provisions of either the Foreshore Acts or the Planning & Development Acts, depending on the location of such

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schemes. This arose primarily because of the jurisdictional issues associated with the position of the Mean High Water Mark (MHW). Prior to 2000, development seaward of the MHWM were governed by the Foreshore Acts and the responsibility of the Department of Marine or equivalent while development landward of the MHW came under the jurisdiction of the adjoining local authority and subject to the provisions of the planning legislation (O’Hagan and Cooper, 2001; O’Hagan and Cooper, 2002 and O’Connor et al., 2009). The result of such a situation was that practical implementation of a coastal protection scheme varied greatly between local authorities despite the fact that they all work from the same legislative base (O’Hagan and Cooper, 2002). Under the Foreshore Act, 1933, the Minister has the power to grant foreshore licences which authorise the licensee to ‘place or erect any articles, things, structures or works on such foreshore, to remove any beach material from, or disturb any beach material in, such foreshore, to set and take any minerals in such foreshore to a maximum depth of 30 feet or to use or occupy such foreshore for any purpose’. A strict interpretation of this provision implies that it is necessary to obtain a foreshore licence before undertaking any coastal protection works. This was rarely done by local authorities given the delays in obtaining foreshore licences from the Department concerned but also due, in part, to the fact that most protection schemes were in response to emergency events. Issues surrounding the actual jurisdiction of local authorities can also be linked to the practical approach taken: local planning authorities, as instruments of local government under the aegis of the Department of the Environment, Heritage & Local Government, had jurisdiction only as far as MHW yet they had legal responsibilities relating to the planning and protection of infrastructure, which often included coastal roads and flood defences. The result was that local authorities assumed the de facto role of coastal manager albeit without formal jurisdiction. The Planning and Development Act, 2000 sought to address these issues surrounding administration of coastal zones and the foreshore in particular. The Act provides, in section 225, that for development purposes foreshore which adjoins the functional area of a local authority requires planning permission. This, generally, does not apply to local authority-led development. However, any local authority-led or commissioned, coastal protection works must obtain permission from An Bord Pleanála (Irish Planning Appeals Board). In essence, this means that coastal protection works are subject to the provisions of both the planning and foreshore legislation both of which were administered by different Government departments. In an attempt to further streamline the administration of the foreshore, the Foreshore Act was amended in 2009 in order to transfer certain foreshore responsibilities from the Minister of Agriculture, Fisheries and Food to the Minister for the Environment, Heritage and Local Government. The result of this is that now, for the first time in the history of the State, coastal management and the majority of foreshore responsibilities come under the same central Government department. Ironically, coastal protection is viewed as a separate and distinct responsibility and since January 2009 this portfolio has been the responsibility of the Office of Public Works (OPW), as was the case when the Coast Protection Act was enacted in 1963. The OPW are the State agency responsible for flood risk management. As part of this remit the OPW have recently commenced extensive mapping and survey work intended to inform future policy and management in areas at risk from fluvial and coastal flooding. This is expanded upon in the next section. As part of future policy development the OPW are also examining the existing Coast Protection Act, 1963 with a view to proposing legislative amendments in order to deliver a more responsive and integrated management approach to erosion and coastal protection (J. Casey, Engineer, Coastal Protection e OPW, pers.

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comm., 25/8/10). It is important to note here that the existing framework for coastal protection works operates separately to the foreshore regime but must still fulfil foreshore licensing requirements. 3.2. Policy framework Ireland’s coastline spans some 6,500 km (5,800 km in the Republic of Ireland) and is largely rural in character with scenic landscapes and seascapes (National Coastal Erosion Committee, 1992). A study carried out by the National Coastal Erosion Committee in 1992 estimated that over 3000 km of coast in the Republic of Ireland is classified as soft with over half that considered ‘at risk’ from erosion (National Coastal Erosion Committee, 1992). When planning infrastructure development, there is no formal framework for assessing risk per se. If the planners in a local authority receive an application for a development in an area at risk from erosion, for example, they may consult informally with engineers in that authority to garner their expert opinion. This is not standard procedure, however, and may vary according to the nature of the development and the personnel involved. At the national level, the National Roads Authority (NRA) has overall responsibility for planning and supervision of construction and maintenance works on ‘National’ roads though it sometimes discharges these functions through the appropriate local road authority. ‘National’ roads tend to be in the central parts of the country and not along the coast consequently there is no intrinsic ‘erosion risk’ assessment. The NRA, however, implement a robust pre-planning framework which looks at the engineering risk associated with construction and can then incorporate specific design features should a risk arise that needs to be addressed. Any potential problematic issues would therefore become apparent in the pre-planning stages. The National Coastal Erosion Committee’s study concluded that a dedicated coastal management policy rather than a purely coastal erosion policy was needed. This was later taken forward by the three responsible central Government departments at that time and culminated in the publication of “Coastal Zone Management e A Draft Policy for Ireland” in 1997 (Brady Shipman Martin, 1997). Within the Coastal Protection chapter of that policy, it is stated that “the best policy for Ireland is probably to accommodate natural changes by preventing or reducing development and investment in areas at risk”. The draft policy recognised that resources for addressing erosion and flooding were likely to ‘remain inadequate’ in the future and explicitly stated that “at the very least, more study and analysis is needed to quantify the losses that will result if the problems identified . are not tackled in the near future” (Brady Shipman Martin, 1997). The chapter concluded by stating that “due to the limited available budget for coast protection and the likelihood of an increased need for protection, a national strategic approach [to erosion management] is required. There is a need to prioritise those areas that require action against erosion and also the type of response most appropriate” (Brady Shipman Martin, 1997). Immediately prior to that policy, in 1996, the [then] Department of the Marine, responsible for coastal protection along with Forbairt, Ireland’s agency tasked with looking after indigenous industry, took part in an EU-funded LIFE project, entitled ‘ECOPRO e Environmentally Friendly Coastal Protection’. This included the development of coastline monitoring methods adaptable to various types of coast, an evaluation of various coastal protection and management methods; case histories of a number of these methods; and also considered improved means of co-ordination. The project culminated in the publication of a Code of Practice (Government of Ireland, 1996) which was intended to act as a guide to engineers tasked with finding a solution to a particular coastal protection problem. Each local authority engineer with coastal protection responsibilities received a copy of the Code of

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Practice. This Code of Practice was consistent with the existing system of practice-based coastal defence management which had developed in the absence of a coherent national level policy on erosion management (O’Connor et al., 2009). Because of the inadequacies of the legal framework, and resultant lack of a requirement to monitor the coast, much of the necessary baseline data which informs erosion management decisions is largely absent for most Irish coastal areas. This is discussed in the next section. Despite the various policy recommendations contained within the National Coastal Erosion Committee’s study (1992) and the draft policy for CZM (Brady Shipman Martin, 1997), none of these have ever been taken forward. The latter also included wider coastal management options to move towards better integration in the decision making process, to overcome the sectoral approach and the strong land/marine divide, which characterise the national approach to coastal management (Brady Shipman Martin, 1997). There also remains no strategic policy document for erosion management though the development of a National Coastal Protection Strategy for the management of risk represented by coastal erosion and flooding was identified as a strategic objective of the DCMNR in 2005 (Department of Communications, Marine and Natural Resources, 2005). As part fulfilment of this objective an Irish Coastal Protection Strategy Study (ICPSS) was launched in 2003. Phase One of this comprised of an overview of coastal protection generally in Ireland and gave recommendations for further elements of the Study. Phase two of the ICPSS began in April 2004 and comprises of nine work packages including the creation of a GIS coastal database, identification of erosion and flood risks, economic assessment of assets at risk, development of a coastal flood warning system and a decision support tool for prioritising coastal protection projects. Work within the various packages is undertaken on a regional basis (Phase three), with plans to roll this approach out nationally (Phases four and five). These will cover the South West Coast (4) and West and North West Coast (5) respectively. Work will include the acquisition of new airborne Lidar survey data. The resulting flood and erosion risk maps will be made available to local authorities to support the management of these risks and inform future development decisions. The work is also expected to deliver on Ireland’s legal obligations deriving from EU legislation on flood risk management while simultaneously allowing for aspects of climate change impacts to be taken into account at various governance levels.

4. Application of the frame of reference 4.1. Generic frame of reference The generic Frame of Reference for implementing coastal erosion management policy is presented in Fig. 1. This frames the concepts derived from the EUROSION project into a policy context and makes it possible to assess the effects of any policy or change of policy in an iterative manner. In order to utilise the Frame of Reference for the Inch Beach case study, firstly a strategic objective and secondly an operational objective had to be defined, shown in Fig. 9. The strategic objective is to provide for the proper planning and sustainable development of the area. This is one of the key responsibilities of the local authority and is derived from the Planning and Development Act, 2000 and the legally-binding County Development Plan (CDP) which contains the planning objectives of the local authority for their functional area. In the absence of any national or local coastal management policy, it is not unusual for broad coastal management objectives to be contained within the CDP. In the Kerry County Development Plan 2003e2009, for example, the coast is recognised as “a vital asset with limited capacity to absorb development” (Kerry County Council, 2003). The operational objective is to prevent damage to infrastructure. In the CDP in relation to coastal protection it is stated that it is an objective of the Council to “prohibit development where existing coastal defences, properly maintained, would not provide an acceptable standard of safety over the lifetime of the development” (Kerry County Council, 2003). Coastal protection works which have not been the subject of a recognised design process and have not been assessed in terms of their likely impact on the marine environment are also prohibited. Another objective is to “implement site specific management policies to ensure that erosion is not initiated or aggravated by the impact of human activity” (Kerry County Council, 2003). Given the regional and local economic value of the road which passes along the Inch coastline, its protection is a core function of the local authority. To help deliver both the strategic and operational objectives within the Frame of Reference a set of steps in policy making are included. The first two of these, the Quantitative State Concept and the Benchmarking procedure are absent from management at the Inch site (Fig. 10). The Quantitative State Concept depends on

Strategic objective To provide for proper planning & sustainable development

Operational objective Prevent damage to infrastructure

1. Quantitative State Concept

2. Benchmarking Procedure

CSI • Monitoring • System knowledge • Measurement • Modelling

Desired state

3. Intervention procedure

4. Evaluation procedure

Current state

Fig. 9. Initial Frame of Reference for Erosion Management at Inch Strand, Co. Kerry.

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coastal state indicators which are derived from monitoring, knowledge of the system, measurements and modelling. The CSIs therefore inform both the reference state and the current state, both of which are needed to define and quantify the EUROSION concept of Favourable Sediment Status. In Inch, and elsewhere in Ireland, there is no law or policy requirement to carry out baseline monitoring or physical measurements of any kind, and as a result when it comes to making a decision on erosion management there is no fundamental information from which to make an informed decision. Lack of monitoring information means that quantification of the four EUROSION concepts is difficult as is the development of recognised physical CSIs. As the latter information is absent, this has knock-on effects for the Benchmarking Procedure as there is no information to benchmark against. Consequently, the manager has no option but to proceed directly to the Intervention Procedure. In reality the CSI for Inch was determined to be coastline “position” specifically a change of a scale large enough to create a public demand for action rather than a change in the measured actual coastline position derived from regular monitoring. In the Inch case study, Intervention took the form of the coastal defence features shown in Fig. 3. Given the financial outlay involved in implementing a scheme of this type, it is a requirement to ensure that the structure is functioning as it was intended to do. The Evaluation Procedure, or fourth step in the Frame of Reference, effectively involves a monitoring assessment of the structure rather than the beach itself or the structure’s impact upon the beach. The Evaluation Procedure hence becomes a measure of the perceived success of the coastal protection measure. The monitoring undertaken as part of the evaluation usually takes place shortly after construction, perhaps six months later so no conclusions can be made on the impact of the structure on the system or consequent system response to the structure. 4.2. Institutionalisation of the frame of reference Along with demonstrating the suitability of the Frame of Reference to coastal erosion management, another core objective of the CONSCIENCE project was to demonstrate the ‘operationalisation’ or implementation of the Frame of Reference at the institutional level. The national law and policy framework, outlined above in Sections 3.1 and 3.2, highlight the complexities surrounding coastal management in Ireland and the associated jurisdictional issues. Local authorities assume the role of coastal managers. The Kerry County Development Plan 2003e2009 recognises this stating that “the scope of land use planning and the development plan is limited to matters directly under the control of planning legislation and cannot, therefore, deal with all the issues that arise on the coastal

Strategic objective To provide for proper planning & sustainable development

Operational objective Prevent damage to infrastructure

1. Intervention procedure

2. Evaluation procedure

CSI Coastline position

Fig. 10. Current Frame of Reference for Erosion Management at Inch Strand, Co. Kerry.

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zone” (Kerry County Council, 2003). In terms of erosion management, this can be viewed in two ways. Firstly as erosion is a natural coastal process it is not explicitly addressed in the planning legislation and cannot be considered as a local authority responsibility. Alternatively, and a more preferential view is that, coastal protection works are a foreshore development and therefore subject to the requirements of the Planning & Development Act, as amended. Either way, the provision and protection of infrastructure is a local authority responsibility, implying that the emplacement of the protection measures at Inch Strand to protect the adjoining road was a responsibility of the local authority. However, like any development on the foreshore any such works also require a foreshore licence from the relevant Government department thereby already complicating the application and implementation of the Frame of Reference. This ‘real’ institutional Frame of Reference, as it operated in Inch at the time of the CONSCIENCE project, is presented in Fig. 11. The real institutional Frame of Reference indicates that both the strategic and operational objectives were the responsibility of the local authority, namely Kerry County Council. The problem arising here is that, due to the complex legal framework and lack of a national coastal or erosion management policy, the responsibilities of the local authority do not exist in isolation and require involvement with many other institutional actors in both local and central Government. Proceeding directly to the Intervention and Evaluation Procedure stages in the Frame of Reference, the local authority can progress largely on its own. Involvement of other actors comes about as a result of legal and funding procedures, both of which are outside the control of the local authority. The foreshore licensing regime is arduous and painstakingly slow with the result that when upgrading or emplacement of coastal protection works are required to respond to an emergency event a foreshore licence cannot be obtained in the necessary timeframe. In a similar vein, minor coastal protection works, equating to V500,000 or less, are funded through the Minor Works Scheme administered by the Office of Public Works. Funding for major works is considered separately through other programmes such as the Catchment Management Programme. Funding allocation is not guaranteed and is decided on a priority basis. It should be noted that in Ireland there is no recurrent dedicated budget for coastal protection. In the National Development Plan 2007e2013, approximately V23 million was targeted for protecting the coast from the impact of both flooding and erosion for the whole of Ireland (Government of Ireland, 2007). Given the length of Ireland’s coast that is susceptible to erosion and the fact that the localised measures at Inch cost approximately V4 m it is hard to envisage that these resources will cover current and future demands. An idealised Frame of Reference for the Irish situation is presented in Fig. 12. This would require fundamental changes to the existing law, policy and institutional frameworks. Ideally strategic objectives for coastal and erosion management would be set out by national Government and implemented by local government. This would help ensure consistency both horizontally, between different local authorities, and vertically, between local authorities and responsible central Government departments/agencies. The operational objective would then be implemented by the relevant local authority but this would be consistent with the nationally defined strategic policy objective(s). In reality, given the current economic climate, it is unlikely that a dedicated national strategy would be supported by dedicated national funds, however, in the idealised Frame of Reference the local authority would have both a legal obligation and the necessary resources to define relevant Coastal State Indicators through routine monitoring programmes. Ideally this would be benchmarked through the regional office of the national government department or agency tasked with coastal management/protection. This regularly generated monitoring data

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Strategic objective To provide for proper planning & sustainable development National Government implemented by Local Government (Planning & development Act, 2000; Foreshore Acts, 1933-2005; Coastal Protection Act, 1963 and associated Regulations)

Operational objective Prevent damage to infrastructure

Kerry County Council National Government implemented by Local Government (Planning & development Act, 2000; Foreshore Acts, 1933-2005; Coastal Protection Act, 1963 and associated Regulations)

1. Intervention procedure

2. Evaluation procedure

Fig. 11. Institutional Frame of Reference for Erosion Management at Inch Strand, Co. Kerry.

would in turn be supplied to that regional office to inform policy development and/or amendment. Intervention, or nonintervention as the case may be, would continue to be carried out by the local authority but decisions would be based on readily available, robust scientific data. Any intervention would then be evaluated by the regional office of the national Government department or agency tasked with coastal management.

5. Discussion Inch Strand appears to be regularly subjected to storm-driven erosion at the levels recorded during this research. The levels of erosion recorded here (>10 m) are significant but the actual impact is limited given the lack of development behind the fore-dune and the fact that the most severe storms are confined to the off-season.

STRATEGIC OBJECTIVE: To provide for proper planning & sustainable development National Government implemented by Local Government Implementation of existing relevant policy and review of contradictory Acts to create a new piece of legislation

OPERATIONAL OBJECTIVE Prevent damage to infrastructure Kerry County Council

1. Quantitative State Concept

2. Benchmarking Procedure

3. Intervention procedure

4. Evaluation procedure

Kerry County Council

National Government (through regional office)

Protective Measures Kerry County Council

Impact of protective measures

Delineate Sediment Cell Identify Strategic Sediment Reservoir

• • • •

CSI Monitoring System knowledge Measurement Modelling

National Government (through regional office)

Favourable Sediment Status

Current Sediment Status

Fig. 12. Idealised Institutional Frame of Reference for Erosion Management at Inch Strand, Co. Kerry.

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It is also important to note that the coastal protection on Inch Strand was not commissioned to protect the beach directly but to preserve the integrity of the coastal tourism route above. On most of the unprotected section of the beach these storminduced erosional phases in the Winter months are to be expected. Given that the dune face position stabilised in late Spring and early stage accretion was noted, this suggests that this is part of a natural annual cycle of erosion and accretion. However given the lack of data, especially in the offshore, the mechanism of sediment movement on and offshore is not fully understood and would require further investigation in order to give a more detailed description of the processed involved. The storms recorded were significant, but they were not extreme enough to trigger erosion on the massive scale that has been recorded on a longer decadal scale (c.30e50 years) (Orford et al., 1999). It is evident from consultation with the coastal managers - as primary stakeholders - that they perceive no issue with the concepts defined under EUROSION and can readily identify why the terms could be useful. However in practice they are frustrated by a lack of data, making it impossible to apply these concepts as part of their operational management strategy (Mulder et al., 2009). The concept of the Frame of Reference for coastal erosion management was accepted by stakeholders, however again frustration was expressed that it was impossible to populate the frame given the lack of key data sets (Mulder et al., 2009). These issues surrounding the application of both the concepts and therefore the Frame of Reference in Ireland are a direct result of the law, policy and institutional frameworks that are currently in place. While the primary stakeholders may not have been familiar with the Frame of Reference itself, they could appreciate how the iterative approach it supports could be beneficial. Given the lack of a monitoring programme, and the current absence of a policy driver to affect a change, the management of erosion at Inch will remain reactive rather than pro-active, the latter being favoured as part of an Integrated Coastal Zone Management approach. This is true for many other locations, not just Ireland. In south Wales, for example, temporal coastal data had not been collected as part of strategic monitoring with the result that new infrastructure failed leaving the coastal protection authority in a precarious financial and legal position (Phillips et al., 2009). Although there is currently no dedicated national policy driver for the management of erosion, this is likely to change as a result of recent European legislation. The Floods Directive, for example, requires Member States to carry out a preliminary assessment to identify the river basins and associated coastal areas at risk of flooding by 2011. For these areas, responsible authorities are then required to draw up flood risk maps by 2013 and subsequently flood risk management plans by 2015 which are focused on prevention, protection and preparedness. This Directive applies to both inland waters and coastal waters across the European Union. In Ireland, its implementation has already commenced with the Office of Public Works rolling out a national flood and erosion mapping programme which will subsequently inform the development of catchment management plans. The long standing issues surrounding local authority jurisdiction and their role in coastal management needs legal clarification. If the current system is to continue, whereby a foreshore licence is required for coastal protection works, there is a need to examine how this process could be ‘fast-tracked’ in order to respond to emergency situations. Departmental policy to date has required an Environmental Impact Assessment to accompany any application for a foreshore licence. Arguably this adds to the delays already experienced in obtaining licences. The existing foreshore legislation is currently under review and it is expected that the new regime will introduce a much more effective and efficient licensing

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system. It will, however, continue to operate separately but in addition to the Office of Public Works’ coastal protection regime. 6. Conclusions From the experience of attempting to define the four key EUROSION concepts and apply the Frame of Reference for coastal erosion management at Inch Strand, the following conclusions can be drawn:  The concepts developed under EUROSION are scientifically robust but their application/scope for application is dependent on reliable baseline data backed by an ongoing monitoring scheme.  Even in data poor locations, the CONSCIENCE Frame of Reference is very useful and can be effective if used as an aspirational goal or used to persuade local authorities to monitor / national government to develop policy (institutional framework to produce an integrated management approach).  In the absence of measured (and comparable) Coastal State Indicators (CSI), intervention tends to be reactive rather than planned and the CSI can become subjective (coastline “position”).  Coastal managers, as key stakeholders, still have to manage the coast regardless of the quality of data available. They need adequate resources in order to put in place monitoring schemes and without an adequate policy driver it is unlikely that local authorities will ring-fence the requisite funding.  Future legislation may provide the impetus to establish the types of monitoring programmes required to manage the coastlines in general and coastal erosion in particular in a more integrated and pro-active manner.  The non-application of the EUROSION terms at Inch is not indicative of less erosion or indeed a reduced need for erosion management at Inch or indeed at a national scale. On the contrary the need for effective erosion management in Ireland and across Europe has never been more prevalent. Acknowledgements The authors would like to recognise the support of the EU FP6 project CONSCIENCE (Project contract No. 044122) in conducting this research. References Brady Shipman Martin, 1997. Coastal Zone Management e A Draft Policy for Ireland. Government of Ireland, Dublin, Ireland. Danish Hydraulic Institute, 2004. MIKE 21 Wave Modelling User Guides, vol. 1. DHI, Horsholm, Denmark. Department of Communications, Marine and Natural Resources (DCMNR), 2002. Value-For-Money Review of Coast Protection Programme, Prepared for the DCMNR by Fitzpatrick Associates (Economic Consultants). DCMNR, Dublin, Ireland. Department of Communications, Marine and Natural Resources (DCMNR), 2005. Statement of Strategy 2005e2007. DCMNR, Dublin, Ireland. European Commission, 2004. Living with Coastal Erosion in Europe e Sediment and Space for Sustainability. Results of the EUROSION Project. Office for Official Publications of the European Communities, Luxembourg. European Parliament and Council, 2002. Recommendation of the European parliament and of the council of 30 may 2002 concerning the implementation of integrated coastal zone management in Europe (2002/413/EC). Official Journal of the European Communities L148, 24e27. Folk, R.L., 1954. The distinction between grain size and mineral composition in sedimentary-rock nomenclature. Journal of Geology 62, 344e359. Government of Ireland (Department of the Marine, Department of the Environment for Northern Ireland, Forbairt, LIFE), 1996. ECOPRO - Environmentally Friendly Coastal Protection Code of Practice. The Stationery Office, Dublin, Ireland. Government of Ireland, 2007. Ireland’s National Development Plan 2007e2013 e Transforming Ireland: a Better Quality of Life for All. The Stationery Office, Dublin, Ireland.

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Kerry County Council, 2003. Kerry County Development Plan 2003e2009. Kerry County Council, Tralee, Co., Kerry, Ireland. Marchand, M. (Ed.), 2010. Concepts and Science for Coastal Erosion Management: Concise Report for Policy Makers. Deltares, Delft, The Netherlands. Mulder, J., Bucx, T., O’Hagan, A.M., Gault, J., 2009. Review of Existing Knowledge and Management Approaches of Coastal Erosion Report Compiled as Part of the CONSCIENCE Project. National Coastal Erosion Committee, 1992. Coastal Zone Management: a Case for Action. County and City Engineers Association and the Irish Science and Technology Centre, Dublin, Ireland. O’Connor, M., Lymbery, G., Cooper, J.A.G., Gault, J., McKenna, J., 2009. Practice versus policy-led coastal defence management. Marine Policy 33, 923e929. O’Hagan, A.M., Cooper, J.A.G., 2001. Extant legal and jurisdictional constraints on Irish coastal management. Coastal Management 29, 73e90. O’Hagan, A.M., Cooper, J.A.G., 2002. Spatial variability in approaches to coastal protection in Ireland. Journal of Coastal Research SI 36, 544e551.

Orford, J.D., Cooper, J.A.G., McKenna, J.,1999. Mesoscale temporal changes to foredunes at Inch Spit, South-West Ireland. Zeitschrift für Geomorphologie, N.F 43 (4), 439e461. Phillips, M.R., Powell, V.A., Duck, R.W., 2009. Coastal regeneration at Llanelli, South Wales, UK: lessons not learned. Journal of Coastal Research SI 56, 1276e1280. Thompson, E.F., 2002. Hydrodynamic analysis and design conditions. In: Pope, J. (Ed.), Coastal Engineering Manual, Part II, Chapter 8, Engineer Manual 1110-21100. U.S. Army Corps of Engineers, Washington, DC, U.S.A. van Koningsveld, M., Davidson, M.A., Huntley, D.A., 2003. Matching science with coastal management needs: the search for appropriate coastal state indicators. Journal of Coastal Research 21 (4), 399e411. Vijaykumar, N., Gault, J., Devoy, R.J.N., Assireu, A., Dunne, D., O’Mahony, C., 2004. An experience on wind hindcast to stimulate a wave hindcast over the Irish Sea. In: 13th Brazilian Congress of Meteorology Proceedings Fortaleza, Ceará, Brazil. Wintle, A., Clarke, M., Musson, F., Orford, J.D., Devoy, R.J.N., 1998. Luminescence dating of recent dune formation on inch spit, Dingle Bay, Southwest Ireland. The Holocene 8, 331e339.