Clontarf Flood Defence Report


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Clontarf Flood Defence Report

  1. 1. To the Lord Mayor and Report No. 368/2011Members of Dublin City Council Report of the Assistant City Manager Clontarf Flood Defence Project Final Report to Dublin City Council Meeting 5th December 2011 1. IntroductionAn interim Report on the Clontarf Flood defence project incorporating the North City ArterialWater main (Report number 315/2011) and an accompanying presentation was made to theDublin City Council Meeting on 7th November 2011.That interim report confirmed that: Coastal Flooding presents a serious risk for the people in Clontarf. This project is about protecting people – their lives, homes and livelihoods. At present, Clontarf is one of the most vulnerable areas of the City and is at risk of severe flooding from the sea. If nothing is done to prevent it, a flood may cause major damage to the area, disrupting business and daily life and possible injury or even loss of life. Dublin City Council is working to prevent that. The modified proposal outlined in detail to the City Council in November is landscaped gentle grass mounding and some sea walls where mounding is not possible at four existing car parks. Many solutions were examined for this project but the modified proposal provided for the best balance between providing adequate protection for the community and conserving the amenity value of the area.
  2. 2. -2-Determining a solution to flooding is about striking a balance between these two competingpriorities and in adjusting the scheme, Dublin City Council has rebalanced the proposal totake better account of the amenity value of the area, while at the same time providingessential flood defence. 2. Debate at City Council meeting on 7th NovemberA full discussion and debate took place at the meeting of the City Council in November.During that meeting the following motion was passed by the City Council:“That this Council rejects the original Clontarf Flood Defence Plan and respects the right ofthe people of Clontarf to accept or reject the proposed revisions as outlined at the NovemberCity Council meeting. This Council further demands that following the information sessionsplanned by the City Council over the next month concerning the revised plans and feedbackto local representatives, that a vote be taken on the final report at the December City Councilmeeting to determine whether or not to proceed with the revised plan and no contracts willbe signed in advance of the vote taking place”The City Manager informed the City Council that: A series of Public Information sessions would be held to allow individuals examine the proposals and to make observations up to a closing date of 28th November 2011. A report would be issued to the Council Meeting in December following the information sessions including feedback from the information sessions and addressing funding and planning for the modified proposal.The City Manager confirmed that he would act in accordance with the decision of the CityCouncil on the flood defence project. 3. Actions from 7th November 2011 to date.The Public Information Sessions were held in Clontarf Castle Hotel on the evenings of 16th,17th, and 23rd November and on Saturday 19th November 2011. Public notices were placedin the national press giving details of the information sessions. A leaflet drop was carried outin the area and all of the houses and properties identified as being at risk of coastal floodingwere included in the leaflet drop. Additional notices advertising the information sessionswere placed in local businesses.A full report on these sessions and the feedback received is contained in Appendix 1 andAppendix 3.In parallel with the above Public Information sessions, the Clontarf Residents’ Associationand Clontarf Business Association held separate briefing sessions and made presentationson potential alternative options (not developed to detailed design stage) that had beenincluded in the original 2005 Dublin Coastal Flood Protection Project Report drawn up byDublin City Council Consultants Royal Haskoning.
  3. 3. 3- 4. Defending Clontarf from Coastal Flooding4.1 Clontarf Flood RiskThe coastal flood risk maps prepared as part of the Coastal zone risk assessment study arein compliance with National Guidelines and they show the area that will flood if a 1 in 200year coastal flood event occurs (which has a 0.5% probability of occurring in any one year).The areas indicated to be at risk are also shown in the recently published draft mapsprepared by the OPW as part of their Preliminary Flood Risk Assessments (July 2011).Coastal Flood Risk in Dublin Bay has been analysed in great detail and is well understood.Major floods, such as occurred in 2002, arise when a number of separate risk factors alloccur at the same time. It is not possible to predict when all of these factors will coincide inthe future but there is a very high risk that, at some time in the future, a significant coastalflooding event will strike Clontarf sea front and, if the area remains undefended, this willresult in serious flooding of residential properties and businesses.Coastal flooding occurred in 1982, 2002 and was narrowly avoided in 2010 when the tidalsurge arrived just 4 hours after high tide. The proposed coastal defence scheme is designedto mitigate this risk. 4.2 Proposed modified SchemeThe modified scheme was outlined at the November City Council meeting and at the publicinformation sessions. In response to residents’ concerns, Dublin City Council is proposingunder the modified scheme to reduce the heights of proposed flood defences at Clontarf, sothat many of the views that would have been interfered with would be restored.The modified flood defence solution, recommended by the Consultants, consists mainly oflandscaped grass mounds to keep the sea at Clontarf at bay. Where grass mounds wouldnot work, due to existing car parks at four locations, (Hollybrook Road, Clontarf Baths,Vernon Ave and The Yacht Club/Dublin Bus car park) sea walls would be provided. 83% of the flood defences would be below 1.524 metres (5ft) and largely consists of landscaped grass mounds to maintain uninterrupted pedestrian access to the sea front. The seafront pathway would be a well-lit, open and safe place for families, walkers and joggers after the flood defence is built. The gradient of both the mounds and the pathway would allow people to walk across the mounds with ease and the paths would be fully accessible to all
  4. 4. -4-4.3 Clontarf Residents’ Association and Clontarf Business Association separatebriefing sessionsDuring the Dublin City Council Public Information sessions, as outlined above, the ClontarfResidents’ Association and the Clontarf Business Association (CRA/CBA) also set up andadvertised parallel Public Information sessions.At these, the CRA/CBA presented photomontages of their interpretation of some of theoptions that had been included in the original 2005 Dublin Coastal Flood Protection Project(DCFPP) Report produced for Dublin City Council by consulting engineers Royal Haskoning.In particular they focused on what was referred to as Option 1 – which was an option to raisethe existing sea wall and the nearby promenade.In their presentations to the public the CRA/CBA used the indicative levels and indicativeconcepts in the 2005 Report, taking no account of the fact that these were never developedbeyond outline design stage.The result was that people attending the CRA/CBA presentation were told that Option1 consisted of raising the existing sea wall by “three to four feet” (900mm to 1.2m).No account was taken of the significant variation in the existing ground or sea wall levels.This was then held up in comparison with Dublin City Council’s modified proposal whichconsisted of proposed defences which are generally no higher than 1.4m (4 feet 7 inches)but, in order to be effective, do have to rise to a maximum height of 2.1m (7 feet) where theexisting ground levels are very low near Oulton Road.Those attending the public information sessions were, understandably, impressed with theCRA/CBA interpretation of Option 1 and compared this most unfavourably with the DCCmodified proposals.This is despite the fact that, in reality, if Option 1 were to be adopted and take full account ofthe wave modelling and detailed design to which the DCC proposals were subjected, theheight of this Option would be higher than the DCC option.This fact was also pointed out in Sect 2.1 of the previous Interim Report to the CityCouncil on 7th November 2011.Furthermore, Option 1 was also predicated in the DCFPP Report on the construction ofgroynes or breakwaters on the seaward side of the existing wall. This would have had totake place within a Natura 2000 designated site. Without these groynes, the proposedOption 1 wall would be even higher again.Dublin City Council officials approached the CRA/CBA and expressed concern that theirpresentations may give the wrong impression to those attending, and offered to have Dublin
  5. 5. -5-City expert flood defence consultants Haskoning meet with the CRA/CBA team to explainthis. However, this offer was rejected (See Appendix 2). We were subsequently advised thatthis offer was interpreted as an attempt by the Council to ridicule the work of the CRA/CBA.All alternatives set out in the 2005 Report and other variations on these were consideredfully at the outset of this project in 2005.Any option that is to provide an effective flood defence must consist of some form of physicalbarrier between the Clontarf Road and the sea. Such a barrier must be located at the seawall, in the existing promenade or at the existing cycle track and any such barrier will be atleast as high, if not higher, than the current proposals.Consultants Haskonings have considered the potential options presented by the CRA/CBAat their separate public information sessions and statements that a “three or four feetincrease in existing sea wall” would be sufficient to protect Clontarf. They met withCouncillors on 24th November 2011 and confirmed that: Any effective flood defence constructed along the line of the existing sea wall will be between 400mm and 800mm higher than the height of the current proposed mound at the equivalent location along the promenade, with consequent impact on sea views etc. Wave heights are bigger at that point whereas an inland barrier takes advantage of the waves breaking on the existing sea wall first and consequently is lower. Furthermore, if the promenade is to be raised accordingly, the promenade will now fall towards the road (quite dramatically in places) resulting in increased risks if the sea wall were overtopped. The cost could be of the order of four times the cost of the current scheme (that would put it at €12m excluding design etc. and well beyond any cost benefit ratio.There is no option which involves raising the sea wall by “three or four feet” as confirmed byexperts Haskoning (as set out in appendix 4) nor any other option likely to be morefavourably received.It is essential that City Council are aware of this expert advice when considering whether toaccept or recommend rejection of current modified proposal. 5. Feedback from Public Information sessions to Current ProposalsAppendix 3 provides a more comprehensive analysis of the issues that have been raised bythose who attended the Public Information sessions and those who contacted Dublin CityCouncil directly. The information sessions were attended by over 2,000 people. Publicity in
  6. 6. -6-some media portraying the recommended scheme as a 10 feet high wall stretching along the3 Km. of coast (which was never the case), was most unhelpful and contributed to polarisingopinion against the defence scheme.A substantive issue is that the current proposal will “split” the promenade and could result ina security and safety risk to those using the area beside the sea and that they would not bevisible from the rest of the promenade or from the road.A related issue is the impact of the proposed mounding on the amenity value and enjoymentof the promenade.One issue that has caused great difficulty to this project’s chances of being accepted is thefact that the existing ground levels vary quite significantly over the 3km length. In particularthere is an area directly east of the Clontarf Baths near Oulton Road where, due to the verylow ground levels, any proposed coastal flood defence structure, regardless of what option isadopted, will have to be at least 2m high at this point.If the overall area stretching to 3km is to be protected from the sea some form of barrier isrequired. The barrier must run the full 3km identified at risk of coastal flooding. The height ofthe proposed barrier has been designed by International Consultants. There is little point inflood defences if they are so low that they are not going to prevent the sea from floodinghouses and properties. 6. Funding, Planning and Procurement IssuesFunding – All schemes identified as requiring funding from Central Government must bedesigned to meet coastal defence guidelines and must also pass cost benefit requirements.Funding for this scheme is included in the 2011 OPW budget and can be drawn down if acontract is signed in 2011 for works to begin construction in 2012. At this stage, even if theCouncil agree to proceeding with the project, it is likely the further planning process (seebelow) will extend into next year. This being the case we would argue for the funding to bedeferred until next year.Planning - If it is decided to proceed with a modified design, as outlined to the City Councilat the November meeting, based on the concept approved by An Bord Pleanala in 2008, itwill require a resubmission to An Bord Pleanala. There is scope in the legislation to havesuch an amendment dealt with by An Bord Pleanala under current legislation without a fullresubmission of an EIS particularly if recommended by Dublin City Council.In parallel, other issues, such as the requirement for a new Appropriate Assessment, couldbe addressed. It is likely that a formal screening process would be required and based onthe extent of the assessment carried out already under the EIS process, this screeningprocess could be done in parallel with a revised submission to An Bord Pleanala.
  7. 7. -7-Procurement of Contractor – A tender process has been completed and a contractor hasbeen recommended to be appointed subject to the normal approvals process. Thisprocurement would allow construction in 2012 subject to approval of the planningsubmission by An Bord Pleanala and completion of the Appropriate Assessment of themodified proposal. In effect, if it is decided to proceed with an amended flood defenceproject the existing procurement will stand.If it is decided not to proceed with the modified flood defence project the currentprocurement process (including the watermain procurement) will also be terminated. Whilethe intention, in this scenario, is to proceed with the watermain project the revised contractwould require a new tender process. The new procurement could take up to a year.The process of getting any new flood defence project underway would be dependent onDublin City Council being provided the necessary dedicated funding to recruit a project team,following which the previously set out (and lengthy) project process would get underway. 7. CommunicationsAs advised at the November Meeting all statutory processes were completed in relation tothe original proposal and notification was given to the relevant parties (see correspondenceattached in Appendix 5). We have accepted that while the Council did comply with thestatutory requirements, notified Residents Associations and held information sessions therecould have been a far more collaborative process with the Residents and BusinessAssociations but not all of the responsibility for failure to fully engage with the process lieswith the Council alone. As late as January 2011 the Clontarf Residents Associationconfirmed that “DCC has spent years planning the flood defence scheme for the area andthat it has been scrutinised and passed by An Bord Pleanala. It does not interfere with theproposed SPA and it should not be altered” 8. RecommendationI have noted that public opinion in the Clontarf area is virtually wholly opposed to themodified Flood Defence Project going ahead. But in making my recommendation a numberof factors have been taken into account. Both the OPW and our Consultants agree that themodified proposal provides an effective flood defence for the area at risk in Clontarf. TheOPW are willing to approve the modified proposal although it is noted that we have noguarantee of funding beyond 2011 at this point. It is possible to proceed to construction in2012 (subject to funding and resolution of the outstanding planning matters). I am also takingon board the advice of our Consultants that any option involving modification of the sea wallwould be significantly higher than the modified proposal and would face similar objections.All alternative suggestions for flood defences raised during the information sessions havebeen commented on in the report from our expert Consultants (see appendix 4). There aretherefore no other alternative options which can protect Clontarf and which would beacceptable to people based on feedback from the information sessions.
  8. 8. -8-For these reasons and given the overriding requirement to protect the area I am of the viewthat the amended proposal is the only feasible option that can be achieved in the short tomedium term.It has been clearly represented to us by many of the Elected Members that both the EISapproved project and the more recently modified proposal are not acceptable for a numberof reasons including the security and amenity issues. It is within the rights of the members toprevent the flood defence proposal going ahead.If this is the decision then officials of the City Council will seek to meet with the ResidentsAssociation and the Business Association in order to consider the outcome and implicationsof the decision.Seamus LyonsAssistant City ManagerAttachments:Appendix 1 – Report on Public ConsultationAppendix 2 – Correspondence relating to potential impact of raising sea wall as outlined in ClontarfResidents’ Association and Clontarf Business Association separate briefing sessionsAppendix 3 Analysis of issues raised during Dublin City Council Public Information sessions.Appendix 4 – Report by Expert Flood Consultants Haskonings on modified Scheme and all potentialalternatives following feedback from Public Information sessions.Appendix 5 Correspondence regarding EIS Process and Planning Report.
  9. 9. Appendix 1 - Report on Public Consulation
  10. 10. Open Day Displays
  11. 11. Project Information Brouchure
  12. 12. Open Day Leaflet
  13. 13. Press Release
  14. 14. Appendix 2 - Correspondence relating to potential impact of raising sea wall as outlinedin Clontarf Residents Association and Clontarf Business Assocation seperate briefing sessions
  15. 15. Appendix 3 - Analysis of issues raised during Dublin City Council Public Information Sessions
  16. 16. Appendix 4 - Report by Expert Flood Consultant Haskonings on modified Scheme and all potential alternatives following feedback from Public Information Sessions
  17. 17. Appendix 5 - Notice regarding EIS Process