The following brief of evidence was given by Professor Andrew Cooper at the second Bord Pleanala Oral Hearing on 30 March 2007 on behalf of the Greystones Protection and Development Association.
1. Qualifications and Experience
I graduated in 1984 from Queen’s University Belfast in geology, and I was initially employed in southern Scotland on a geological reconnaissance project with BP Minerals. I moved to South Africa in 1985 where I worked for two years in the University of Natal on sedimentation in estuaries and a further seven in the CSIR on coastal processes. I gained my MSc and PhD from the University of Natal in 1987 and 1991, respectively. I took up a senior lectureship at the University of Greenwich, UK in 1993 and a Readership at the University of Ulster in 1994. I was appointed to a personal chair in coastal studies in 2004. I have published more than 200 papers in the field of coastal processes and coastal management and have worked on a variety of research projects in the UK, Ireland, the EU and around the world.
2. Introduction
My evidence today is on behalf of the Greystones Protection and Development Association, and arises from the Association’s concern about the applicant’s proposal for beach nourishment to mitigate the impacts of its proposed marina development at Greystones Harbour.
In my evidence I will address the question of the mechanism of delivery of beach recharge material to the site, the volume thereof and the long term implications of this approach.
My evidence will have particular regard to the question raised by the Board in its letter dated 14 August 2006 to Wicklow County Council. In that letter, the Board stated
“Noting the already restricted road access to the site, the Board is not satisfied on the basis of the submissions made that the required beach nourishment of approximately 6,000 tonnes per annum cannot be brought to site by sea in order to mitigate any potential negative traffic impacts resulting from the proposal to bring this material by road, and consequently through the future completed development”.
3. The Applicant’s Proposal for Beach Nourishment
The applicant considers, on the basis of numerical modelling of coastal processes, that accelerated coastal erosion is likely to result from the proposed development. It has been proposed that this be addressed by rock armouring of the seaward edge of the old dump site and beach nourishment in the area north of this for a period of 30 years. The recharge material is to be sourced from gravel quarries on land and transported by lorry to the beach at a rate of 6000 m3 per year, following an initial emplacement of 30,000 m3. Calculation of these required sediment volumes relies on future predictions of shoreline behaviour under various scenarios. Because the volume of material being transported to the beach is the subject of the board’s letter of August 14th to the developer, I would therefore like to look briefly at the means by which these required volumes are derived.
3.1. Beach behaviour: actual and predicted
Beaches are loose accumulations of sand and/or gravel that can adapt their shape to variations in wave, tide and wind conditions, sediment supply (volume of available material) and sediment type (size, shape and composition). They do so within a fixed geological framework. They may be bounded by headlands or underlain or backed by rock of variable resistance to erosion. The beach adjusts to the combined effect of these parameters at any given time and hence achieves a dynamic equilibrium. A change in any one of these factors may produce a change in the beach itself.
Construction of the marina changes the framework within which the beach exists. This changes the physical boundaries within which the beach exists, which in turn alters the wave dynamics. This adjustment in two of the major controls on beach shape and position will produce a change in the beach shape. There is no accurate way of modelling the likely future shape of the beach under such conditions .
The models (part of the DHI Litpack suite) that were used by the applicant (Greystones Harbour EIS Appendix 6) to predict shoreline evolution for different marina scenarios are complex numerical models that aim to make various predictions regarding, coastal hydraulics, volumes of longshore sediment transport, and future shoreline positions under various scenarios. In order to make accurate predictions of future shoreline positions and sediment transport rates, such models must take account of all the variables that impact on sediment transport .
There are several reasons, however, that mean that such models cannot produce accurate simulations. They include the following:
Certain important parameters to be omitted from calculations (e.g. packing and density of sediment);
Not all important model parameters and their interactions are understood. Scientific understanding of transport of mixed grain populations is very limited ;
There is a ubiquitous inability to accurately characterise the starting conditions (grain size, wave conditions, precise beach shape, underlying rock depth, resistance to erosion etc); For example, the Greystones beach is described in the developer’s reply to the board’s leter of August 14th 2006, simply as “shingle with a median size of 5mm”. This gives no indication of the range and proportions of grain sizes and shapes.
Some questionable relationships are used in models (e.g. relationship between wave angle and longshore drift rate);
Constants are frequently used to adjust model outputs to achieve ‘reasonable’ predictions. For example, a range of wave theories can be selected as well as bed roughness parameters and wind or currents can be omitted or included as the operator chooses- this enables the operator to adjust the model result to match a target value;
The unpredictability of future wave, tide and weather conditions.
The role of extreme but infrequent storms, that may strongly influence or even dominate shoreline behaviour cannot be predicted or simulated. These may produce much more change in a few days than decades of ‘normal conditions’. At Kilpatrick beach in northern Wexford, for example, storms in early December 2006 caused more than 10m of erosion on a beach and dune that had been essentially stable for the previous decade;
Using the models produces a single quantitative prediction without giving any indication of the probability of such a scenario actually occurring. One can have little confidence in such a simulation and in the case of Greystones, the predicted impact of the marina derived by modelling is therefore quite uncertain. As a consequence, the volume of material required to ‘remedy’ the situation cannot not known. The volumes cited (6000m3 per year and an initial capital emplacement of 30,000 m3 may be much too low or much too high. Raising the amount from 4000m3 to 6000m3 as has been done in the EIS to ‘ account for the inaccuracy of the 1-D model) has no basis in reality, as the model has no error bands.
3.2. Required volume of nourished sand
The practice of placing sediment on an eroding beach to replace or augment natural sediment supply is now widespread practice in many heavily developed coastal areas. Because of the complexity of interactions outlined above, it is not possible to accurately predict future beach nourishment requirements or longevity of nourished beaches. Models are commonly used to make such predictions but they suffer from several fatal shortcomings.
The inability to predict performance of beaches using models relates to several factors. One is the inability to describe the grain size; Beaches contain a range of different grain sizes distributed throughout the beach). Another is the inability to describe the wave conditions; Natural seas are affected by a range of wave sizes that interact with each other, with the wind and with any currents to produce complex fluid motions that vary over time. The role of storms is particularly poorly understood. A third is the chaotic behaviour of the weather that produces waves and currents.
Studies have shown that nourished beaches almost always last for a shorter time than that predicted. Usually, the poor performance is explained by an unexpected storm and there have been several instances when entire nourished beaches have been eroded within a few days. The inaccuracy of models is certainly a contributing factor to poor performance, but the overwhelming dominance of over-predicting the longevity of nourished beaches shows an ill-placed optimism in many such exercises.
The potential situation whereby nourished material is washed away rapidly by a storm is not considered in the developer’s report.
As a result of sea level rise and climate change resulting in the likely increased incidence of storms in the Irish Sea, the volume of material required to maintain the beach position will not remain constant but an ever greater volume of material will be required in the future. There is no commitment to providing a greater volume than that laid out in the developer’s proposal. Furthermore, any increase in volume would increase the traffic volume and level of disturbance on the beach.
3.3. Suitability of proposed fill material
The beach at Greystones derives its sediment from the eroding cliffs of fluvio-glacial sediment at the rear of the beach. This material has been initially sorted by ancient, glacial-related processes and when it is eroded by modern waves it undergoes further sorting on the beach. This produces a distinctive distribution of sediment according to grain size and shape on the beach. A particular packing arrangement is achieved whereby the grains fit together in a particular way. Using material from a different source (an inland quarry) and depositing it directly on the beach by a different mechanism (dumping from a lorry) produces a different packing arrangement and will cause the beach to respond differently to wave processes. Nourished beaches are usually found to erode more rapidly than their natural predecessors.
In addition, no quantitative analysis of the textural characteristics of the proposed source material and the natural beach source material has been undertaken to determine the differences. The high incidence of broken stones in the Ballyhorsey quarry material and its angular nature contrasts markedly with the smoothed and rounded nature of the present beach material. The possibility of use of offshore marine sediments is considered in the developer’s reply but is subject to many uncertainities. The land-sourcing and transport of nourishment material seems to be favoured.
3.4. Environmental value of nourished beach
Beach nourishment involves a high level of vehicular and mechanical activity around and on the beach. This disturbance will have adverse impacts on plant and animal life on the beach. Upper beach vegetation will be disturbed by the movement of imported material across and on the beach. The beach infauna will be buried and the different styles of packing and probability of fine interstitial grains may affect biological colonisation and use of the beach surface. It is unlikely to be packed and sorted by mechanical emplacement in the same way as it would be by waves and this may impact on the recreational value of the beach.
3.5. Sustainability of nourished beach
Above all, it is important to note that the beach nourishment is being proposed as an antidote to problems that will arise through construction of the proposed marina. It is an acknowledgement that an undesirable impact will be created and is a proposed mechanism to reduce this impact. The nourishment is proposed to continue to be financed and undertaken for thirty years by the marina operating company. At the end of thirty years, however, when the nourishment stops, the adverse impacts of the marina will still remain. The resulting problem or accelerated erosion, even if the nourishment performs as the developers expect, is therefore not mitigated but simply forestalled or postponed. The question of who will take responsibility for the adverse impacts on the coast at that time remains unresolved. It would seem unreasonable for the public to take over such responsibility since the impact is the result of private development. If not, how would the adverse impacts be managed at that time?
Once humans interfere with a shoreline, there is usually no going back. The first intervention typically produces undesirable impacts which require additional interventions to ’remedy’ them. They in turn produce further impacts and the beach is transformed from a natural system to an increasingly human-influenced system, dependant on political decisions and economics for its survival. The artificially nourished beaches of southern Spain, backed by sea walls and defended by offshore breakwaters are ultimate expression of this urbanisation of beaches. There, the high volume of beach-dependant tourism activity provides an economic driver to sustain beach nourishment. No such driver exists at Greystones.
Nourishing a beach creates an artificial condition and a commitment to sustain that beach for ever. This is a major commitment for this and future generations to enter into, in order to resist changes that are the result of a one-off marina development.
4. Conclusions
On behalf of the Greystones Protection and Development Association we suggest to An Bord Pleanála that this development will have unpredictable and unquantifiable impacts on a natural beach system. The proposed mitigation by beach nourishment will have negative impacts on the natural environment and the local infrastructure. The volume of material required to maintain a given beach position cannot be known and any increase in volume required would have additional environmental impacts. Most importantly, the practice is not sustainable. The development will create a permanent environmental problem that will persist (and most probably be excerbated) beyond the thirty year lifespan of the proposed interventions.
Andrew Cooper
Friday 27 April 2007
Monday 26 February 2007
Beach Nourishment at Greystones North Beach
1 BEACH NOURISHMENT
The proposed beach nourishment program is unreasonable, financially and environmentally unsound and will cause permanent, significant disruption in the town for many years to come.
The proposed development creates a dependency on an ongoing regime of beach nourishment. Without beach nourishment, “the result expected is severely increased erosion of the cliff toe north of the development”. The proposed development effectively “creates a requirement” for coastal protection because it puts a man-made development in an erosion-prone area.
The proposed development is expected to increase erosion levels north of the CPO boundary. As explained on page 257 of the full EIS:
· With beach nourishment, erosion is expected to be “slightly worse than the do nothing scenario”
· Without beach nourishment, there would be “severe erosion at the north end of the bay”
1.1 Reply to An Bord Pleanala by SISPAR regarding beach nourishment
In their reply to An Bord Pleanala dated October 2006 SISPAR conclude that:
· A sufficient supply of naturally rounded land based quarry material for use as beach nourishment material on Greystones North beach was not identified by the developer. This admission alone makes the proposal for an open – ended regime of beach nourishment totally unsustainable.
· The developer is proposing to use material sourced from Ballyhorsey quarry in Wicklow. I believe that the material sourced from this quarry which contains more than 50% broken edges makes it totally unsuitable for placing on a recreational beach where the people will be walking, fishing and swimming.
· The developers proposal is for the ongoing annual transportation of in excess of 12,000 tonnes of the beach nourishment material from Ballyhorsey quarry by road through the town of Greystones and through the proposed new development. The idea of annual convoys of heavy goods vehicles transporting quarried shingle through built up residential areas in Greystones to dump on the north beach is unsustainable boarding on the farcical.
· The Codling Bank which does have suitable material and can be transported by sea but is completely dependent on obtaining a licence from the Department of Communications, Marine and Natural Resources.
It is clear that the creation of a dependency for beach nourishment on Greystones North Beach arising from this development is totally unsustainable and uncertain. Uncertainty exists both from finding a reliable supply of the necessary material and the cost of this material.
1.2 Beach nourishment outside of the CPO area
Clon Ulrick in Section 8.4.2 of his Brief of Evidence states that “The shingle beach nourishment will be placed considerably further north than is envisaged in the Variation to the County Development Plan.” In Figure 3: “Proposed solution, showing modelled cliff-toe development after 30 years” this area will extend well beyond the CPO Boundary up to 214600N. This proposed nourishment scheme will encroach well within the area of a proposed Special Amenity Area Order “SAAO” for Bray Head (Section 8.4.4.3 County Wicklow Heritage Plan 2004-2008). Under whose authority will such an aggressive beach nourishment scheme be permitted in the area of this proposed SAAO?
The COWI Hydraulic Studies and Coastal Morphology Appendix VI Coastal Modelling Report - Coastline evolution, Scenario 4: New development with beach nourishment to hold the line
It states that “It is recommended that the nourished material shall be of the same type as the beach material. The nourishment volumes are assumed to originate elsewhere.”
"Coastline erosion rates vary considerably annually and seasonally and localised single events – such as cliff slides – are smoothed out over time.”
1.3 Commitment from Sispar – only for 30 years with annual cap with no commitment from Wicklow County Council
It is proposed at Section 3.4.5 (Page 254) of the EIS that “the concession company will provide sufficient shingle to limit the beach erosion to a maximum of 21 m at a fixed point, close to the point of maximum erosion, at the end of the 30 year concession period. This is subject to a cap of 6,000m3 (12,000 tonnes) per annum average replenishment if the erosion exceeds predictions. Within the CPO boundary, the retreat will be limited to a maximum average of 10 m. The beach in front of the revetment will be kept a minimum 15 m wide, measured at approximately mean sea level. The beach profile will be measured annually to ensure that the targets are achieved over the 30 year concession period.”
I do not consider that the proposed annual measurement of the beach profile is sufficient. The measurement process must be carried out on a regular ongoing fashion in order to identify sudden beach loss quickly to facilitate a timely response to mitigate against sudden accelerated erosion.
The EIS is silent as to who will be responsible for funding the ongoing cost of beach replenishment following the expiry of the 30 year concession period. There is no commitment from Wicklow County Council that they will fund the cost of this ongoing beach replenishment.
There is no commitment from Sispar to increase the level of beach replenishment material if the erosion rate exceeds predications. This could leave the soft shoreline of Greystones North Beach even more exposed to the increased forces of erosion resulting from a new harbour development.
1.4 Limitations of beach nourishment techniques
Predicting the volumes of beach nourishment materials required and the timing of future nourishment episodes is very inexact. The models used to estimate the 6,000m3 annual requirement used oversimplified assumptions which may very well be way off target.
The ECOPRO Code of Practice (page 66) on the subject of beach nourishment states that:
“without a groyne system to keep the sediment in place replenishment will be periodically required. These ongoing costs should be taken into account when carrying out a cost-benefit analysis.”
Section 3.4.6 of the EIS states that “it cannot be ruled out that the rate of erosion could be higher than that suggested by the modeling, even with the factor of safety. Coastal modeling is not a precise science and 30 years is a long time to extrapolate long term rates of coastal retreat. In addition, long term changes such as changes to the weather patterns or the offshore shingle banks could change the coastal processes and the rates of coastal retreat.”
BEACH NOURISHMENT BASICS by Don Barber, Geology Dept., Bryn Mawr College describes disadvantages to a long term commitment to a beach nourishment which can include:
· “Beach nourishment material often (in fact, usually) erodes faster than the natural material on the beach. A good rule of thumb is that nourished beaches erode two or three times faster than natural beaches. Erosion rates can differ widely, however. The biggest factor for the lifetime of a nourished beach is the number of storms that affect the beach. Storms are unpredictable, so nourished beach lifetimes are unpredictable too. The amount of sand added per yard of beach length and the sand placement design determine the new beach width. Wider nourished beaches last longer.
· Beach nourishment is expensive, and must be repeated periodically. Very few nourishment projects last longer than 5 years without significant costly renourishment.
· The beach turns into a construction zone during nourishment with an ongoing negative impact on the local community and environment.
· The process of nourishment may damage or destroy marine and beach life by burying it, squishing it under bulldozers, changing the shape of the beach, or making the water near the beach too muddy.
· The material added to the beach is often different from the natural beach material. This means that the new material may have smaller or larger diameter sand grains than the natural beach. Such differences in "grain-size" affect the way waves interact with a beach.”
1.5 Further observations relating to proposed Beach Nourishment at Greystones North Beach
· The developers believe that the only viable option for sourcing the beach nourishment material required is to pump it ashore from the Codling Bank. They state that the material required “is generally found along beaches and rivers and is not in very plentiful supply from quarries operating in Ireland”. The Codling Bank option provides the rounded material which is not obtainable form land based quarries.
· However the developers would require a licence from the Department of Communications, Marine and Natural Resources to retrieve material from the Codling Bank. However the likelihood of being granted a licence is uncertain.
· The removal of offshore gravel from the Codling Bank can have direct and often unforeseen impacts on coastal stability as it influences sediment availability as well as inshore wave and current influences on the coast. As very little sediment, other than mud is now entering the Irish Sea the existing sand and gravel deposits on off shore banks such as the Codling Bank are a non-renewable resource.
· The recommended option of the developer is “to develop a yearly beach nourishment programme with material brought in by road from local quarries in a safe and organised manner.” This is therefore a very short term plan even though they have already committed to this for 30 years.
· This option appears to have been selected reluctantly by the developers arising from the many negative impacts resulting from it. This proposal will therefore result in the dumping of material which is inappropriate for a recreational beach (angular stones with sharp jagged edges) using road transport with obvious negative traffic impacts.
· Also it is clear that the developers expect the land based quarry material to erode much more quickly than the Codling Bank material. They state that if Codling Bank material were to be used that “beach nourishment could be carried out in 5 to 10 year periods”. This compares to the annual beach nourishment required if land based quarry material is used.
· The potential effects of climate change with rising sea levels and increases in the intensity and frequency of storms and sea surges do not appear to have been considered by the developer in regard to their beach nourishment proposals. It is likely that future sea level rise will increase the volume of material needed for nourishment if the coast is to be maintained in its present position. This will increase both volume and costs of future nourishment materials. The estimate annual requirement of 12,000 tonnes of nourishment material may well increase dramatically over the years. This raises very serious issues with regard to the long term financial affordability (and viability) of this very long term financial commitment.
· I have been advised by Professor Orrin Pilkey (James B. Duke Professor of Earth Sciences) that “the experience in the USA is that there is no guarantee that beach nourishment will continue forever. So promises to prevent erosion forever by nourishment are hollow.”
· The beach nourishment proposal is therefore unsustainable from financial and material sourcing perspectives.
The proposed beach nourishment program is unreasonable, financially and environmentally unsound and will cause permanent, significant disruption in the town for many years to come.
The proposed development creates a dependency on an ongoing regime of beach nourishment. Without beach nourishment, “the result expected is severely increased erosion of the cliff toe north of the development”. The proposed development effectively “creates a requirement” for coastal protection because it puts a man-made development in an erosion-prone area.
The proposed development is expected to increase erosion levels north of the CPO boundary. As explained on page 257 of the full EIS:
· With beach nourishment, erosion is expected to be “slightly worse than the do nothing scenario”
· Without beach nourishment, there would be “severe erosion at the north end of the bay”
1.1 Reply to An Bord Pleanala by SISPAR regarding beach nourishment
In their reply to An Bord Pleanala dated October 2006 SISPAR conclude that:
· A sufficient supply of naturally rounded land based quarry material for use as beach nourishment material on Greystones North beach was not identified by the developer. This admission alone makes the proposal for an open – ended regime of beach nourishment totally unsustainable.
· The developer is proposing to use material sourced from Ballyhorsey quarry in Wicklow. I believe that the material sourced from this quarry which contains more than 50% broken edges makes it totally unsuitable for placing on a recreational beach where the people will be walking, fishing and swimming.
· The developers proposal is for the ongoing annual transportation of in excess of 12,000 tonnes of the beach nourishment material from Ballyhorsey quarry by road through the town of Greystones and through the proposed new development. The idea of annual convoys of heavy goods vehicles transporting quarried shingle through built up residential areas in Greystones to dump on the north beach is unsustainable boarding on the farcical.
· The Codling Bank which does have suitable material and can be transported by sea but is completely dependent on obtaining a licence from the Department of Communications, Marine and Natural Resources.
It is clear that the creation of a dependency for beach nourishment on Greystones North Beach arising from this development is totally unsustainable and uncertain. Uncertainty exists both from finding a reliable supply of the necessary material and the cost of this material.
1.2 Beach nourishment outside of the CPO area
Clon Ulrick in Section 8.4.2 of his Brief of Evidence states that “The shingle beach nourishment will be placed considerably further north than is envisaged in the Variation to the County Development Plan.” In Figure 3: “Proposed solution, showing modelled cliff-toe development after 30 years” this area will extend well beyond the CPO Boundary up to 214600N. This proposed nourishment scheme will encroach well within the area of a proposed Special Amenity Area Order “SAAO” for Bray Head (Section 8.4.4.3 County Wicklow Heritage Plan 2004-2008). Under whose authority will such an aggressive beach nourishment scheme be permitted in the area of this proposed SAAO?
The COWI Hydraulic Studies and Coastal Morphology Appendix VI Coastal Modelling Report - Coastline evolution, Scenario 4: New development with beach nourishment to hold the line
It states that “It is recommended that the nourished material shall be of the same type as the beach material. The nourishment volumes are assumed to originate elsewhere.”
"Coastline erosion rates vary considerably annually and seasonally and localised single events – such as cliff slides – are smoothed out over time.”
1.3 Commitment from Sispar – only for 30 years with annual cap with no commitment from Wicklow County Council
It is proposed at Section 3.4.5 (Page 254) of the EIS that “the concession company will provide sufficient shingle to limit the beach erosion to a maximum of 21 m at a fixed point, close to the point of maximum erosion, at the end of the 30 year concession period. This is subject to a cap of 6,000m3 (12,000 tonnes) per annum average replenishment if the erosion exceeds predictions. Within the CPO boundary, the retreat will be limited to a maximum average of 10 m. The beach in front of the revetment will be kept a minimum 15 m wide, measured at approximately mean sea level. The beach profile will be measured annually to ensure that the targets are achieved over the 30 year concession period.”
I do not consider that the proposed annual measurement of the beach profile is sufficient. The measurement process must be carried out on a regular ongoing fashion in order to identify sudden beach loss quickly to facilitate a timely response to mitigate against sudden accelerated erosion.
The EIS is silent as to who will be responsible for funding the ongoing cost of beach replenishment following the expiry of the 30 year concession period. There is no commitment from Wicklow County Council that they will fund the cost of this ongoing beach replenishment.
There is no commitment from Sispar to increase the level of beach replenishment material if the erosion rate exceeds predications. This could leave the soft shoreline of Greystones North Beach even more exposed to the increased forces of erosion resulting from a new harbour development.
1.4 Limitations of beach nourishment techniques
Predicting the volumes of beach nourishment materials required and the timing of future nourishment episodes is very inexact. The models used to estimate the 6,000m3 annual requirement used oversimplified assumptions which may very well be way off target.
The ECOPRO Code of Practice (page 66) on the subject of beach nourishment states that:
“without a groyne system to keep the sediment in place replenishment will be periodically required. These ongoing costs should be taken into account when carrying out a cost-benefit analysis.”
Section 3.4.6 of the EIS states that “it cannot be ruled out that the rate of erosion could be higher than that suggested by the modeling, even with the factor of safety. Coastal modeling is not a precise science and 30 years is a long time to extrapolate long term rates of coastal retreat. In addition, long term changes such as changes to the weather patterns or the offshore shingle banks could change the coastal processes and the rates of coastal retreat.”
BEACH NOURISHMENT BASICS by Don Barber, Geology Dept., Bryn Mawr College describes disadvantages to a long term commitment to a beach nourishment which can include:
· “Beach nourishment material often (in fact, usually) erodes faster than the natural material on the beach. A good rule of thumb is that nourished beaches erode two or three times faster than natural beaches. Erosion rates can differ widely, however. The biggest factor for the lifetime of a nourished beach is the number of storms that affect the beach. Storms are unpredictable, so nourished beach lifetimes are unpredictable too. The amount of sand added per yard of beach length and the sand placement design determine the new beach width. Wider nourished beaches last longer.
· Beach nourishment is expensive, and must be repeated periodically. Very few nourishment projects last longer than 5 years without significant costly renourishment.
· The beach turns into a construction zone during nourishment with an ongoing negative impact on the local community and environment.
· The process of nourishment may damage or destroy marine and beach life by burying it, squishing it under bulldozers, changing the shape of the beach, or making the water near the beach too muddy.
· The material added to the beach is often different from the natural beach material. This means that the new material may have smaller or larger diameter sand grains than the natural beach. Such differences in "grain-size" affect the way waves interact with a beach.”
1.5 Further observations relating to proposed Beach Nourishment at Greystones North Beach
· The developers believe that the only viable option for sourcing the beach nourishment material required is to pump it ashore from the Codling Bank. They state that the material required “is generally found along beaches and rivers and is not in very plentiful supply from quarries operating in Ireland”. The Codling Bank option provides the rounded material which is not obtainable form land based quarries.
· However the developers would require a licence from the Department of Communications, Marine and Natural Resources to retrieve material from the Codling Bank. However the likelihood of being granted a licence is uncertain.
· The removal of offshore gravel from the Codling Bank can have direct and often unforeseen impacts on coastal stability as it influences sediment availability as well as inshore wave and current influences on the coast. As very little sediment, other than mud is now entering the Irish Sea the existing sand and gravel deposits on off shore banks such as the Codling Bank are a non-renewable resource.
· The recommended option of the developer is “to develop a yearly beach nourishment programme with material brought in by road from local quarries in a safe and organised manner.” This is therefore a very short term plan even though they have already committed to this for 30 years.
· This option appears to have been selected reluctantly by the developers arising from the many negative impacts resulting from it. This proposal will therefore result in the dumping of material which is inappropriate for a recreational beach (angular stones with sharp jagged edges) using road transport with obvious negative traffic impacts.
· Also it is clear that the developers expect the land based quarry material to erode much more quickly than the Codling Bank material. They state that if Codling Bank material were to be used that “beach nourishment could be carried out in 5 to 10 year periods”. This compares to the annual beach nourishment required if land based quarry material is used.
· The potential effects of climate change with rising sea levels and increases in the intensity and frequency of storms and sea surges do not appear to have been considered by the developer in regard to their beach nourishment proposals. It is likely that future sea level rise will increase the volume of material needed for nourishment if the coast is to be maintained in its present position. This will increase both volume and costs of future nourishment materials. The estimate annual requirement of 12,000 tonnes of nourishment material may well increase dramatically over the years. This raises very serious issues with regard to the long term financial affordability (and viability) of this very long term financial commitment.
· I have been advised by Professor Orrin Pilkey (James B. Duke Professor of Earth Sciences) that “the experience in the USA is that there is no guarantee that beach nourishment will continue forever. So promises to prevent erosion forever by nourishment are hollow.”
· The beach nourishment proposal is therefore unsustainable from financial and material sourcing perspectives.
Wednesday 21 February 2007
PROPOSED DRAINAGE SCHEME AND HARBOUR ENGINEERING
1 PROPOSED DRAINAGE SCHEME AND HARBOUR ENGINEERING
The Department of the Marine in their submission to An Bord Pleanala dated 16th March 2006 raised very serious concerns as to the suitability of the design of the proposed harbour breakwaters which they felt were too low to prevent severe wave overtopping.
Based on the additional information provided to An Bord Pleanala it appears that Wicklow County Council/Sispar have made no modifications to the engineering design of the proposed harbour breakwaters.
At the oral hearing in March 2006 it was advised by Wicklow County Council/Sispar that “physical wave model tests had been commissioned and would be complete within a three month period”[1]. These physical model tests were commissioned to determine whether/which modifications of the breakwater design were needed. A commitment was given to the Inspector by Wicklow County Council/Sispar that the eventual report would be made available for public inspection.
Wicklow County Council/Sispar have failed to comply with a specific commitment they gave to the Inspector at the Oral Hearing regarding physical wave modelling tests.
The EIA should consider carefully the impact of the proposed coastal works on areas removed from the development. In a case such as this, wave modelling would be a desirable component of the EIA to assess the effect of the coastal transformation on the wave climate in the vicinity of the development.
It is totally unacceptable that the results of the physical modelling tests carried out since the oral hearing have not yet been made available for public inspection by Wicklow County Council/Sispar.The results of these tests are critical in the context of the coastal setting of the proposed development for Greystones for the following reasons:
1.1 Department of Communications, Marine and Natural Resources submission
The Department of Communications, Marine and Natural Resources in their detailed submission dated 16 March 2006 to An Bord Pleanala stated;
· In section 11 “Wave Disturbance Modelling” that “the department would suggest that the project be redesigned to ensure that only acceptable wave heights are achieved in the marina”and that “overtopping should be discussed and analysed in the EIS and an opportunity given for public comment.”
· In section 13 “numerical Models” that use of numerical models such as LITDRIFT and LITLINE” as the sole design tool as has been done in this case needs to be viewed with a very high level of caution”.
· In section 14 “Wave Sheltering” that “details of the wave sheltering assumed in the modelling of the new development are not made available in the EIS” and that “these assumptions are central to understanding the simulations carried out with the new development in place”.
· In section 14 the Department strongly concludes that “if modelling is incorrect, as it appears to be, project design following from such modelling would appear to be highly questionable”.
1.2 Brief of evidence of Clon Ulrick BSc(Eng) at the Oral Hearing
The brief of evidence of Clon Ulrick BSc(Eng) at the Oral Hearing dealing with coastal defences and marine works stated;
· in section 6.2.3 that “the north breakwater, which has a crest height of +6.5 mOD, will be prone to severe wave overtopping during extreme storms” and that it is proposed that the effects of wave overtopping will be investigated by physical modelling”.
· in section 6.2.4 that “the south breakwater, which has a crest height of +6.5 mOD increasing to +8mOD near Cliff Road, will nevertheless be prone to severe wave overtopping during extreme storms” and that “the effects of wave overtopping are being investigated further by physical modelling”.
· in Section 8.2.6 that “physical model tests that are commissioned and will be completed within three months will be required for final assessment of the overtopping and determine whether/which modifications of the breakwater design are needed.”
· in Section 8.7.2 that “the reclamination levels for the residential and commercial developments have been selected to allow for global warming and sea level rise, using conservative (safe) estimates of future sea level rise based on current best practice guidance.” I question how this assertion can be made when the developer does not even have any local tidal data? He also stated that “the area on the south side of the harbour for the car parks and boat storage is a little lower and will be subject to some wave run up in extreme weather events.”
·
1.3 Height of the breakwaters dictated by politicians
It appears that the engineering of the harbour breakwaters has been dictated to by local politicians rather than by sound breakwater engineering advice.
The engineering design of the crest height of the breakwater has been constrained by “the Variation to the County Development Plan to +6.5mOD”.
With the help of the Dun Laoghaire harbour master I checked the heights of the east pier of Dun Laoghaire harbour and found them to be significantly higher than the proposed breakwaters for Greystones Harbour. It should be noted that the east pier of Dun Laoghaire harbour is subject to wave overtopping.
It is unacceptable that fundamental engineering design issues appear to have been made for political reasons rather than from sound marine engineering advice.
1.4 Redesign of the proposed development
The relocation of club buildings further east to positions on or near the south breakwater which are “the most exposed position within the masterplan” place those structures at risk of flooding. It is unacceptable that the results of the physical wave modelling test which would show the extent of the predicted wave overtopping has not been published.
· Breakwater performance, in particular armour stability, maximum runup, wave reflection and wave transmission, is normally checked with a physical model in a wave flume.
· The proposed residential and commercial structures will be totally dependant upon the protection of the harbour breakwaters against the wave energy from the sea.
1.5 History of coastal flooding at Greystones North Beach
The developers admitted at the oral hearing that the destruction of dwellings on the North Beach in the 1930s was not considered by the developers.
· There is a risk to any structures on the seafront especially considering the maritime history of the Greystones North Beach area.
· The OPW website http://www.floodmaps.ie/ details contemporaneous newspaper articles describing a tidal wave which destroyed a number of cottages along this same stretch of coast in the 1930’s. The planned new structures are proposed to be located, not on a flood-plain, but on the sea bed in front of the site where these cottages were destroyed by the sea.
· From an equity perspective it is important that any new structures constructed at Greystones Harbour and North Beach will be fully protected from the risk of inundation from the sea. It would be grossly unfair should individuals who have invested substantial sums of money in these coastal structures suffer substantial flood losses with consequent risk of negative equity as a result of inadequate protective breakwaters.
1.6 Correspondence with Wicklow County Council
On 3rd October 2006 in an email from the Director of Services for Wicklow County Council, Sean Quirke, he stated to me that;
· “Physical modelling was carried out in the Danish Hydraulic Institute. However I have not received the final report to date.”
Following a number of follow up requests to Mr Quirke by me for sight of the physical wave modelling report he advised on 7th December in a further email that;
· “This report is being prepared for the construction phase of the project and is not required for planning purposes. I have spoken to the consultants and they have confirmed that the report will not be finalised until a planning decision has issued in order to take account of any conditions or changes included in the decision.”
In December 2006 both Councillor Deirdre De Burca and Deputy Liz McManus TD requested a copy of the report. These requests were also refused.
While the report was not specifically requested by the Board, it seems unusual the developers would refuse to make it available to a public representative. Indeed if the report did, as claimed in the attached letter confirm that “the fundamental design of the harbour breakwaters… are robust” it might be expected that the developers would be anxious to make the report available to the Board and to the public to alleviate any concerns about the adequacy of the structures.
I therefore respectfully request that Wicklow County Council/Sispar be instructed by An Bord Pleanala to publish the results of the physical wave modelling tests as committed to by them during the oral hearing.
1.7 Drainage scheme for the proposed development
Drainage and watermain drawings were included in the additional information (C001, C002 and C003) however:
· There is no narrative included in the additional to explain the proposed drainage system in the development.
· The drawings on the drainage scheme refer to a number of storm attenuation tanks intended to store a 1 in 50 year storm event of a 4 hour duration. This development will be under an ongoing threat of wave overtopping. This treat will increase over time as the predicted impacts of climate change occur. I believe that the standard set of a 1 in 50 year storm event is insufficient for a flood prone development under the precautionary principle and that these proposed tanks are of insufficient size. I believe that the 1 in 50 year storm event standard is inadequate.
· This is particularly so given the stated policy of Wicklow County Council FR05 on minimum flood design standards as stated in the Local Area Plan for Greystones / Delgany.
1.8 Greystones area Local Tidal Data
In correspondence with Wick County Council it was confirmed that there is no historical record of local tide levels for the Greystones coastal area.
The EIS uses Dublin Port tidal gauge data.
It is unacceptable for a scheme such as this on the Greystones foreshore to proceed without any accurate local historical tidal data.
1.9 Health & safety risk
· The safeguarding of the health and safety of any potential residents in the proposed new residential structures of this development should be of paramount importance.
· The consequences of incorrectly calculating flood levels are not just a risk to parked cars (particularly in the underground car parks) and properties but also to the lives of those who occupy the apartments. A potential health and safety risk therefore arises in the proposed new development at Greystones Harbour and North Bach arising from possibility of flooding of the commercial and residential units and their underground car-parks.
· At the oral hearing Wicklow County Council admitted that the tidal destruction of dwellings on the Greystones North beach in 1929 was not considered in the EIS;
· The existing harbour is subject to wave overtopping. The EIS fails to disclose the height above OD Malin of the existing harbour for comparison purposes;
1.10 Local Area Plan – minimum flood design standards
Wicklow County Council state in the draft LAP for Greystones Delgany in Policy FR05; that all new development must be designed and constructed to meet the following minimum flood design standards;
· For development in general - the 100 year flood
· Along the Coast - the 200-year tide level
However it has been confirmed to me by Wicklow County Council that they have no idea as to what this policy equates to in terms of height above OD Malin.
1.11 Under building car parks
I believe that under the Precautionary Principle that the under building car parking proposed for the development will be at serious risk of inundation from the sea. In particular I draw your attention to the following:
· I note that the under building car parking in Blocks “J”, “I”, “H”, “G”, “F” will have a ground level of 2.2m OD as per Site Section 8-8 DWG No. pSc_08_a
· I note that the under building car parking in Block “G” appears to have a car park gate with ground level of 2.2m OD as per Site Section 9-9 DWG No. pSc_09_a
· I note that Block “D” under building car parking will have a ground level of 1.5m OD as per DWG No. pD1_01_b
· I note that Block “J” under building car parking will have a ground level of 2.2m OD as per DWG No. pJ1_01_a
These levels are below the 3.0 Metres OD referred to in the Wicklow Development Plan 2004-2010 and below the 4.0 Metres OD recommended by John Sweeney who stated that:
“For the east coast of Ireland, we are suggesting that basements of buildings along the quays and the coast shouldn’t be any less than about 4 metres above present sea level,” “It’s important that a certain element of precaution should be taken in terms of anticipating the future storms surges and high water events.”
The clear implication is that these underground car parks will be subject to flooding.
Clon Ulrick in Section 8.7.2 in his brief of evidence stated that “The area on the south side of the harbour for the car parks and boat storage is a little lower and will be subject to some wave run up in extreme weather events.”
It is unacceptable from an economic and safety perspective that the basements of the proposed structures are accepted by the developer as being prone to flooding as the design appears to ignore the reality of rising sea levels.
1.12 Proposed structures adjacent to breakwaters
In extreme weather conditions there will be severe wave overtopping of both the north and south breakwaters. I content that those structures located too close to these breakwaters will be at high risk of flooding and inundation from the sea. Because of the residential nature of this development I believe that this risk raises important health and safety issues. In particular I believe that the following structures will be at high risk of flooding;
· North Breakwater; Blocks “K”, “J”, “I” and H” could be at risk of inundation from the sea in the event of extreme north easterly weather conditions;
· South Breakwater; Block “M” and Block “O” Club Buildings could be at risk of inundation from the sea in the event of extreme east/south east weather conditions.
I request that a safe buffer zone be made in regard to the distances of the proposed residential structures from the harbour breakwaters. I therefore request the Board to instruct the developer that Block K, Block J, Block I, Block H, Block O and Block M be omitted from the proposed development.
1.13 The Greater Dublin Strategic Drainage Study (2005)
· The Greater Dublin Strategic Drainage Study (2005) recommendation regarding criteria for flooding related to sea level rise is to use a 200 year criterion on the basis that flooding from the sea tends to be catastrophic.
· It is proposed by the Greater Dublin Strategic Drainage Study (2005) that most new buildings should have a ground level of +4.0 m OD (Malin Head) in order to ensure that they are protected from the threat of flooding arising from rising sea levels and increased rainfall intensities due to global warming.
· A minimum ground floor threshold of +4.0 OD will be encouraged for all development to satisfy insurance requirements and potential for rising flood levels as a result of future changes in the global climate
1.14 OPW Planning Guidelines for Public Authorities
I believe that the proposed development at Greystones Harbour is at variance to the OPW Planning Guidelines for Public Authorities.
Development that is sensitive to the effects of flooding will generally not be permitted in flood prone or marginal areas (OPW Planning Guidelines for Public Authorities). Preventing such development, where flooding would result in significant hardship, financial losses or costs, will avoid increasing the existing level of risk and will protect the proposed new development from the human (stress and ill-health, for example) and financial costs of flood events. It will also eliminate or reduce expenditure on flood protection measures and compensation.)
The developer acknowledges in Section 3.2 (page 40) of Hydraulic Studies and Coastal Morphology in Appendix VI of the EIS states that:
“..global sea level rise will give rise to further coastal erosion. The sea level rise will allow waves to reach further inshore and will over time cause erosion corresponding to the new equilibrium state.”
1.15 Implications of Climate Change for Northern Ireland: Informing Strategy Development
I draw the Boards attention to important developments regarding flood risk insurance and positional risk which is most relevant in the context of the proposed development. The insurance industry is now using GPS software to identify which properties are vulnerable to flooding. This software is helping insurers make decisions on whether to insure and the premiums involved.
The Scotland and Northern Ireland Forum for Environmental Research (SNIFFER) have released a report titled “Implications of Climate Change for Northern Ireland: Informing Strategy Development”. This report is particularly relevant in the context of the proposed Greystones Harbour development. This policy document states that:
“The accelerated incursion of new building for domestic, tourist and leisure purposes into the NI coastal zone is a major problem for the future. There appears to be a lack of understanding in the private sector, of the risks inherent in building close to the inter-tidal zone, particularly given that planning control cannot be used as a limiting procedure for future external safety purposes. The lack of a NI coastal zone strategy means that there is no effective planning control as a function of coastal proximity. This absence of policy allows the construction of property into what can be both hazardous positions per se and hazardous for surrounding habitats, within the life span of the property. To some extent the issue of positional risk to flooding/erosion has traditionally been seen as best controlled through private insurance. Both primary and secondary insurance companies are actively constructing (taking advantage of recent GIS and remote sensing methodologies) geo-referenced location, risk and knowledge databases about known flood areas. This means that future premiums could be differentially loaded to the point that owners of coastal property deemed to be at risk, may have to live without insurance cover, or be forced to sell below the comparable market value of such a property elsewhere. It is disconcerting that insurance may be the first de facto non-governmental instrument of control, on coastal living (Clarke, 1998). Insurance companies heightened awareness of climate change means that this instrument is already being conditioned for the effects of future climate change. There is the likelihood of a yawning gap between the public and insurer’s view of desirable coastal accommodation in future decades and issues of negative equity becoming common in the coastal zone. The issue of coastal setback controls on construction with/without short-term life spans or depreciation to zero value in the short-term have still not been discussed within the planning-finance-construction sectors. A sign of awareness maturity for NI will be when these concepts are openly discussed.”
I therefore request that the Bord give this report material consideration in the making of its planning decision on the proposed Greystones Harbour development.
The Department of the Marine in their submission to An Bord Pleanala dated 16th March 2006 raised very serious concerns as to the suitability of the design of the proposed harbour breakwaters which they felt were too low to prevent severe wave overtopping.
Based on the additional information provided to An Bord Pleanala it appears that Wicklow County Council/Sispar have made no modifications to the engineering design of the proposed harbour breakwaters.
At the oral hearing in March 2006 it was advised by Wicklow County Council/Sispar that “physical wave model tests had been commissioned and would be complete within a three month period”[1]. These physical model tests were commissioned to determine whether/which modifications of the breakwater design were needed. A commitment was given to the Inspector by Wicklow County Council/Sispar that the eventual report would be made available for public inspection.
Wicklow County Council/Sispar have failed to comply with a specific commitment they gave to the Inspector at the Oral Hearing regarding physical wave modelling tests.
The EIA should consider carefully the impact of the proposed coastal works on areas removed from the development. In a case such as this, wave modelling would be a desirable component of the EIA to assess the effect of the coastal transformation on the wave climate in the vicinity of the development.
It is totally unacceptable that the results of the physical modelling tests carried out since the oral hearing have not yet been made available for public inspection by Wicklow County Council/Sispar.The results of these tests are critical in the context of the coastal setting of the proposed development for Greystones for the following reasons:
1.1 Department of Communications, Marine and Natural Resources submission
The Department of Communications, Marine and Natural Resources in their detailed submission dated 16 March 2006 to An Bord Pleanala stated;
· In section 11 “Wave Disturbance Modelling” that “the department would suggest that the project be redesigned to ensure that only acceptable wave heights are achieved in the marina”and that “overtopping should be discussed and analysed in the EIS and an opportunity given for public comment.”
· In section 13 “numerical Models” that use of numerical models such as LITDRIFT and LITLINE” as the sole design tool as has been done in this case needs to be viewed with a very high level of caution”.
· In section 14 “Wave Sheltering” that “details of the wave sheltering assumed in the modelling of the new development are not made available in the EIS” and that “these assumptions are central to understanding the simulations carried out with the new development in place”.
· In section 14 the Department strongly concludes that “if modelling is incorrect, as it appears to be, project design following from such modelling would appear to be highly questionable”.
1.2 Brief of evidence of Clon Ulrick BSc(Eng) at the Oral Hearing
The brief of evidence of Clon Ulrick BSc(Eng) at the Oral Hearing dealing with coastal defences and marine works stated;
· in section 6.2.3 that “the north breakwater, which has a crest height of +6.5 mOD, will be prone to severe wave overtopping during extreme storms” and that it is proposed that the effects of wave overtopping will be investigated by physical modelling”.
· in section 6.2.4 that “the south breakwater, which has a crest height of +6.5 mOD increasing to +8mOD near Cliff Road, will nevertheless be prone to severe wave overtopping during extreme storms” and that “the effects of wave overtopping are being investigated further by physical modelling”.
· in Section 8.2.6 that “physical model tests that are commissioned and will be completed within three months will be required for final assessment of the overtopping and determine whether/which modifications of the breakwater design are needed.”
· in Section 8.7.2 that “the reclamination levels for the residential and commercial developments have been selected to allow for global warming and sea level rise, using conservative (safe) estimates of future sea level rise based on current best practice guidance.” I question how this assertion can be made when the developer does not even have any local tidal data? He also stated that “the area on the south side of the harbour for the car parks and boat storage is a little lower and will be subject to some wave run up in extreme weather events.”
·
1.3 Height of the breakwaters dictated by politicians
It appears that the engineering of the harbour breakwaters has been dictated to by local politicians rather than by sound breakwater engineering advice.
The engineering design of the crest height of the breakwater has been constrained by “the Variation to the County Development Plan to +6.5mOD”.
With the help of the Dun Laoghaire harbour master I checked the heights of the east pier of Dun Laoghaire harbour and found them to be significantly higher than the proposed breakwaters for Greystones Harbour. It should be noted that the east pier of Dun Laoghaire harbour is subject to wave overtopping.
It is unacceptable that fundamental engineering design issues appear to have been made for political reasons rather than from sound marine engineering advice.
1.4 Redesign of the proposed development
The relocation of club buildings further east to positions on or near the south breakwater which are “the most exposed position within the masterplan” place those structures at risk of flooding. It is unacceptable that the results of the physical wave modelling test which would show the extent of the predicted wave overtopping has not been published.
· Breakwater performance, in particular armour stability, maximum runup, wave reflection and wave transmission, is normally checked with a physical model in a wave flume.
· The proposed residential and commercial structures will be totally dependant upon the protection of the harbour breakwaters against the wave energy from the sea.
1.5 History of coastal flooding at Greystones North Beach
The developers admitted at the oral hearing that the destruction of dwellings on the North Beach in the 1930s was not considered by the developers.
· There is a risk to any structures on the seafront especially considering the maritime history of the Greystones North Beach area.
· The OPW website http://www.floodmaps.ie/ details contemporaneous newspaper articles describing a tidal wave which destroyed a number of cottages along this same stretch of coast in the 1930’s. The planned new structures are proposed to be located, not on a flood-plain, but on the sea bed in front of the site where these cottages were destroyed by the sea.
· From an equity perspective it is important that any new structures constructed at Greystones Harbour and North Beach will be fully protected from the risk of inundation from the sea. It would be grossly unfair should individuals who have invested substantial sums of money in these coastal structures suffer substantial flood losses with consequent risk of negative equity as a result of inadequate protective breakwaters.
1.6 Correspondence with Wicklow County Council
On 3rd October 2006 in an email from the Director of Services for Wicklow County Council, Sean Quirke, he stated to me that;
· “Physical modelling was carried out in the Danish Hydraulic Institute. However I have not received the final report to date.”
Following a number of follow up requests to Mr Quirke by me for sight of the physical wave modelling report he advised on 7th December in a further email that;
· “This report is being prepared for the construction phase of the project and is not required for planning purposes. I have spoken to the consultants and they have confirmed that the report will not be finalised until a planning decision has issued in order to take account of any conditions or changes included in the decision.”
In December 2006 both Councillor Deirdre De Burca and Deputy Liz McManus TD requested a copy of the report. These requests were also refused.
While the report was not specifically requested by the Board, it seems unusual the developers would refuse to make it available to a public representative. Indeed if the report did, as claimed in the attached letter confirm that “the fundamental design of the harbour breakwaters… are robust” it might be expected that the developers would be anxious to make the report available to the Board and to the public to alleviate any concerns about the adequacy of the structures.
I therefore respectfully request that Wicklow County Council/Sispar be instructed by An Bord Pleanala to publish the results of the physical wave modelling tests as committed to by them during the oral hearing.
1.7 Drainage scheme for the proposed development
Drainage and watermain drawings were included in the additional information (C001, C002 and C003) however:
· There is no narrative included in the additional to explain the proposed drainage system in the development.
· The drawings on the drainage scheme refer to a number of storm attenuation tanks intended to store a 1 in 50 year storm event of a 4 hour duration. This development will be under an ongoing threat of wave overtopping. This treat will increase over time as the predicted impacts of climate change occur. I believe that the standard set of a 1 in 50 year storm event is insufficient for a flood prone development under the precautionary principle and that these proposed tanks are of insufficient size. I believe that the 1 in 50 year storm event standard is inadequate.
· This is particularly so given the stated policy of Wicklow County Council FR05 on minimum flood design standards as stated in the Local Area Plan for Greystones / Delgany.
1.8 Greystones area Local Tidal Data
In correspondence with Wick County Council it was confirmed that there is no historical record of local tide levels for the Greystones coastal area.
The EIS uses Dublin Port tidal gauge data.
It is unacceptable for a scheme such as this on the Greystones foreshore to proceed without any accurate local historical tidal data.
1.9 Health & safety risk
· The safeguarding of the health and safety of any potential residents in the proposed new residential structures of this development should be of paramount importance.
· The consequences of incorrectly calculating flood levels are not just a risk to parked cars (particularly in the underground car parks) and properties but also to the lives of those who occupy the apartments. A potential health and safety risk therefore arises in the proposed new development at Greystones Harbour and North Bach arising from possibility of flooding of the commercial and residential units and their underground car-parks.
· At the oral hearing Wicklow County Council admitted that the tidal destruction of dwellings on the Greystones North beach in 1929 was not considered in the EIS;
· The existing harbour is subject to wave overtopping. The EIS fails to disclose the height above OD Malin of the existing harbour for comparison purposes;
1.10 Local Area Plan – minimum flood design standards
Wicklow County Council state in the draft LAP for Greystones Delgany in Policy FR05; that all new development must be designed and constructed to meet the following minimum flood design standards;
· For development in general - the 100 year flood
· Along the Coast - the 200-year tide level
However it has been confirmed to me by Wicklow County Council that they have no idea as to what this policy equates to in terms of height above OD Malin.
1.11 Under building car parks
I believe that under the Precautionary Principle that the under building car parking proposed for the development will be at serious risk of inundation from the sea. In particular I draw your attention to the following:
· I note that the under building car parking in Blocks “J”, “I”, “H”, “G”, “F” will have a ground level of 2.2m OD as per Site Section 8-8 DWG No. pSc_08_a
· I note that the under building car parking in Block “G” appears to have a car park gate with ground level of 2.2m OD as per Site Section 9-9 DWG No. pSc_09_a
· I note that Block “D” under building car parking will have a ground level of 1.5m OD as per DWG No. pD1_01_b
· I note that Block “J” under building car parking will have a ground level of 2.2m OD as per DWG No. pJ1_01_a
These levels are below the 3.0 Metres OD referred to in the Wicklow Development Plan 2004-2010 and below the 4.0 Metres OD recommended by John Sweeney who stated that:
“For the east coast of Ireland, we are suggesting that basements of buildings along the quays and the coast shouldn’t be any less than about 4 metres above present sea level,” “It’s important that a certain element of precaution should be taken in terms of anticipating the future storms surges and high water events.”
The clear implication is that these underground car parks will be subject to flooding.
Clon Ulrick in Section 8.7.2 in his brief of evidence stated that “The area on the south side of the harbour for the car parks and boat storage is a little lower and will be subject to some wave run up in extreme weather events.”
It is unacceptable from an economic and safety perspective that the basements of the proposed structures are accepted by the developer as being prone to flooding as the design appears to ignore the reality of rising sea levels.
1.12 Proposed structures adjacent to breakwaters
In extreme weather conditions there will be severe wave overtopping of both the north and south breakwaters. I content that those structures located too close to these breakwaters will be at high risk of flooding and inundation from the sea. Because of the residential nature of this development I believe that this risk raises important health and safety issues. In particular I believe that the following structures will be at high risk of flooding;
· North Breakwater; Blocks “K”, “J”, “I” and H” could be at risk of inundation from the sea in the event of extreme north easterly weather conditions;
· South Breakwater; Block “M” and Block “O” Club Buildings could be at risk of inundation from the sea in the event of extreme east/south east weather conditions.
I request that a safe buffer zone be made in regard to the distances of the proposed residential structures from the harbour breakwaters. I therefore request the Board to instruct the developer that Block K, Block J, Block I, Block H, Block O and Block M be omitted from the proposed development.
1.13 The Greater Dublin Strategic Drainage Study (2005)
· The Greater Dublin Strategic Drainage Study (2005) recommendation regarding criteria for flooding related to sea level rise is to use a 200 year criterion on the basis that flooding from the sea tends to be catastrophic.
· It is proposed by the Greater Dublin Strategic Drainage Study (2005) that most new buildings should have a ground level of +4.0 m OD (Malin Head) in order to ensure that they are protected from the threat of flooding arising from rising sea levels and increased rainfall intensities due to global warming.
· A minimum ground floor threshold of +4.0 OD will be encouraged for all development to satisfy insurance requirements and potential for rising flood levels as a result of future changes in the global climate
1.14 OPW Planning Guidelines for Public Authorities
I believe that the proposed development at Greystones Harbour is at variance to the OPW Planning Guidelines for Public Authorities.
Development that is sensitive to the effects of flooding will generally not be permitted in flood prone or marginal areas (OPW Planning Guidelines for Public Authorities). Preventing such development, where flooding would result in significant hardship, financial losses or costs, will avoid increasing the existing level of risk and will protect the proposed new development from the human (stress and ill-health, for example) and financial costs of flood events. It will also eliminate or reduce expenditure on flood protection measures and compensation.)
The developer acknowledges in Section 3.2 (page 40) of Hydraulic Studies and Coastal Morphology in Appendix VI of the EIS states that:
“..global sea level rise will give rise to further coastal erosion. The sea level rise will allow waves to reach further inshore and will over time cause erosion corresponding to the new equilibrium state.”
1.15 Implications of Climate Change for Northern Ireland: Informing Strategy Development
I draw the Boards attention to important developments regarding flood risk insurance and positional risk which is most relevant in the context of the proposed development. The insurance industry is now using GPS software to identify which properties are vulnerable to flooding. This software is helping insurers make decisions on whether to insure and the premiums involved.
The Scotland and Northern Ireland Forum for Environmental Research (SNIFFER) have released a report titled “Implications of Climate Change for Northern Ireland: Informing Strategy Development”. This report is particularly relevant in the context of the proposed Greystones Harbour development. This policy document states that:
“The accelerated incursion of new building for domestic, tourist and leisure purposes into the NI coastal zone is a major problem for the future. There appears to be a lack of understanding in the private sector, of the risks inherent in building close to the inter-tidal zone, particularly given that planning control cannot be used as a limiting procedure for future external safety purposes. The lack of a NI coastal zone strategy means that there is no effective planning control as a function of coastal proximity. This absence of policy allows the construction of property into what can be both hazardous positions per se and hazardous for surrounding habitats, within the life span of the property. To some extent the issue of positional risk to flooding/erosion has traditionally been seen as best controlled through private insurance. Both primary and secondary insurance companies are actively constructing (taking advantage of recent GIS and remote sensing methodologies) geo-referenced location, risk and knowledge databases about known flood areas. This means that future premiums could be differentially loaded to the point that owners of coastal property deemed to be at risk, may have to live without insurance cover, or be forced to sell below the comparable market value of such a property elsewhere. It is disconcerting that insurance may be the first de facto non-governmental instrument of control, on coastal living (Clarke, 1998). Insurance companies heightened awareness of climate change means that this instrument is already being conditioned for the effects of future climate change. There is the likelihood of a yawning gap between the public and insurer’s view of desirable coastal accommodation in future decades and issues of negative equity becoming common in the coastal zone. The issue of coastal setback controls on construction with/without short-term life spans or depreciation to zero value in the short-term have still not been discussed within the planning-finance-construction sectors. A sign of awareness maturity for NI will be when these concepts are openly discussed.”
I therefore request that the Bord give this report material consideration in the making of its planning decision on the proposed Greystones Harbour development.
Monday 19 February 2007
Wave modelling on Greystones Harbour
The practice of using these numerical wave modelling programs to justify a shoreline development in this manner was attempted by Wicklow County Council/Sispar in the case of the proposed Greystones Harbour and North Beach development.
However the unreliability of these methods was highlighted by the Department of Communications, Marine and Natural Resources in a submission dated 16 March 2006 to An Bord Pleanala. The Department stated that “if modelling is incorrect, as it appears to be, project design following from such modelling would appear to be highly questionable”.
At a Bord Pleanala oral hearing held in March 2006 Wicklow County Council/Sispar stated that physical wave model tests had been commissioned and would be complete within a three month period. A commitment was given that the eventual report would be made available for public inspection. This would have meant that these physical wave modelling tests should have been completed in and around July 2006. However the results of these tests have yet to be made public despite a number of requests to Wicklow County Council. In December 2006 Councillor Deirdre De Burca and Deputy Liz McManus TD requested a copy of the report. These requests were also refused.
It would appear that the results of these tests are being deliberately suppressed by the developers as they may demonstrate that the proposed harbour breakwaters will be subject to severe wave overtopping with a consequent risk of flooding.
However the unreliability of these methods was highlighted by the Department of Communications, Marine and Natural Resources in a submission dated 16 March 2006 to An Bord Pleanala. The Department stated that “if modelling is incorrect, as it appears to be, project design following from such modelling would appear to be highly questionable”.
At a Bord Pleanala oral hearing held in March 2006 Wicklow County Council/Sispar stated that physical wave model tests had been commissioned and would be complete within a three month period. A commitment was given that the eventual report would be made available for public inspection. This would have meant that these physical wave modelling tests should have been completed in and around July 2006. However the results of these tests have yet to be made public despite a number of requests to Wicklow County Council. In December 2006 Councillor Deirdre De Burca and Deputy Liz McManus TD requested a copy of the report. These requests were also refused.
It would appear that the results of these tests are being deliberately suppressed by the developers as they may demonstrate that the proposed harbour breakwaters will be subject to severe wave overtopping with a consequent risk of flooding.
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