Meath County Council. Meath County Council Boat Slipways. Technical Engineering Report. Job No. : Date: Jan 2018

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1 Job No. : Date: Jan 2018 Meath County Council Meath County Council Boat Slipways Technical Engineering Report 2B Richview Office Park Clonskeagh Dublin 14

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3 CONTENTS Page No. 1 INTRODUCTION General Justification for Works Description of proposed works Trim Castle (MH_BS_003) Bective (MH_BS_004) Navan Old Bridge (MH_BS_005) Navan Centre (MH_BS_006) Navan Weir (MH_BS_007) Stackallen (MH_BS_008) Navan Blackwater (MH_BS_009) WATER LEVELS OPW Records CFRAMS Mapping Comparison of Predicted Flood LEVELS HYDROLOGICAL ASSESSMENT HEALTH AND SAFETY Slip Resistance Working in the River Design Risk Assessment APPENDIX A - DESIGN RISK ASSESSMENT Malone O Regan

4 1 INTRODUCTION 1.1 GENERAL Malone O Regan have been engaged by Meath County Council to prepare a planning submission for the construction of 7 no. Boat Slipways on the River Boyne and the River Blackwater in County Meath. This report describes the proposed Slipway structure and access arrangements for each site. The report also considers health and safety risks and identifies how the proposed designs have mitigated any such risks. This report should be read in conjunction with reports titled Natura Impact Statement, Ecological Appraisal and Preliminary Construction Environmental Management Plan which have been produced by Malone O Regan and are provided under separate cover. It is the intention that this report and the reports mentioned above, along with the relevant drawings will accompany the planning application. 1.2 JUSTIFICATION FOR WORKS The construction of the Slipways are considered an essential requirement to expedite response times in dealing with emergencies and also to improve the health and safety conditions for all personnel launching boats onto the river. The Slipways will be used by the following statutory and voluntary service providers: Civil Defence Meath River Rescue; An Garda Síochána; Irish Coastguard; and, Meath County Council Fire & Rescue services. The Emergency services have been consulted and have confirmed that the identified sites for the Boat Slipways are most suitable and necessary for their operations on the rivers Boyne and Blackwater in the Navan / Trim general area. 1.3 DESCRIPTION OF PROPOSED WORKS Trim Castle (MH_BS_003) Site Setup and Access The proposed Slipway site is located off the Castle Street road in Trim. As part of the construction of the Slipway the will be required to secure the site by providing temporary heras fencing from the entrance at Castle Street to the Slipway location on the bank of the River Boyne. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/171 The existing stoned access to the Sewage Pumping Station and river Boyne at the site location will be used by construction traffic during the works. In its current condition the Malone O Regan 1

5 track is liable to be damaged by the wheels of construction plant. It is likely that the contractor will need to form a temporary haul road using imported hardcore material. Figure 2-1: Trim Castle Site Location Slipway Construction The proposed Slipway will be constructed in the same location as the existing access way to the river Boyne. Details of the proposed Slipway are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/182 and 16009/192. It is envisaged that construction of the Slipway will take 4-6 weeks and will comprise the following steps. A small cofferdam will be created at the toe of the Slipway. The cofferdam will consist of a barrier formed using a number of woven polypropylene tonne bags. The bags will be filled with coarse grain sand which will be well compacted and the bags will sit closely together to minimise gaps. An impermeable, heavy-duty polythene liner will be placed on the retained water side of the barrier to prevent seepage of silt through the barrier into the river. Water will be pumped out of the cofferdam and will pass through a temporary mobile settlement tank before being returned to the river. The settlement tank will contain a number of inclined lamella plates to allow any suspended particles to be removed by gravity. The existing bank will be excavated to achieve the required formation level for the boat ramp. Stone riprap material will be installed at the toe of the ramp. A precast concrete beam will be lifted into position at the toe of the ramp. The use of precast concrete will avoid the requirement for pouring concrete within the river Malone O Regan 2

6 extents. It will therefore minimise the amount of work which needs to be carriedout at the river edge and will reduce the risk of cement and other contaminants from entering the watercourse. 400mm of compacted hardcore will be installed above the existing bank, behind the riprap. A geotextile layer will be installed above the hardcore which will prevent migration of fine particles as a result of the river action. The articulated concrete mattress sections used to form the Slipway deck will be delivered to site and lifted into position using an excavator. The top of the mattress will be temporarily secured by installing a number of galvanised steel tubes driven into the existing bank. The precast mattresses will be manufactured with a number of looped stainless steel cables along their bottom edge. These cables will tie into similar cables which project from the precast toe-beam. An in-situ concrete anchor beam and slab will be installed at the head of the Dycel mattress units, securing them in place. The existing loose stone surfacing to the access road will be replaced with a reinforced grass surface and Grasscrete hardstanding as indicated on drawing 16009/182. An anchor / belay ring will be cast into the slab to make it easier to lift boats in and out of the water. Additional mooring rings will be placed on either side of the Slipway to allow waiting boats to be tied-up without blocking the Slipway. It can be seen on drawing 16009/192 that there is a significant difference between the highest and lowest water levels which are anticipated in the river (refer also to Section 2). The level of the Slipway toe has been set at the 99% river level i.e. the toe of the Slipway will be submerged for 99% of the time and will only be exposed during extreme dry weather events Landscaping and Surfacing The existing ground will be re-graded to tie in with the proposed new Slipway. It is proposed to construct the access road using reinforced grass i.e. a plastic cellular grid, capable of supporting vehicular traffic, will be laid above the existing ground. This product will blend in with the surrounding grassed areas and minimise the visual impact of the access road. At the head of the Slipway and within the proposed vehicle turning area, where significant wheel turning movements are anticipated it is proposed to construct a Grasscrete slab. Grasscrete is a cast in-situ cellular reinforced concrete system with voids created by plastic void formers that will be infilled with grass Drainage The Grasscrete and reinforced grass surfaces proposed for this site are permeable and do not have an impact on the site drainage. The proposed Slipway arrangement includes a small area of impermeable concrete hardstanding at the top of the ramped section. This area of hardstanding has an area of 14m 2. The sloped section of the Slipway will be surfaced using a number of precast Dycel mattress units. These precast units are formed with a regular pattern of voids Malone O Regan 3

7 within the slab which will allow for percolation of rainwater. The area of hardstanding at the top of the Slipway will drain towards these mattress units and it is likely that this runoff will percolate through the holes in the mattress units and that there will be no significant surface water runoff to the river. Therefore, there is no requirement for any drainage systems to be installed as part of the Slipway construction. Malone O Regan 4

8 1.3.2 Bective (MH_BS_004) Site Description The site is bounded by the River Boyne on its southern and eastern boundaries, and by the L4010 and a narrow access road on the northern and western boundaries respectively. Beyond the river and road boundaries surrounding the site, the proposed site is surrounded by predominantly agricultural lands Site Setup and Access Access to the river is off a narrow access road which in turn lies off the L4010 public road. The junction of the L4010 public road with the access road may be difficult for large vehicles or vehicles with a trailer to negotiate. There is a large area of gravel surfacing in the vicinity of the proposed Slipway site which provides adequate turning space for vehicles. There is debris from a dead tree sitting on the gravel surfaced area that will need to be removed from the site. As part of the construction of the Slipway the will be required to secure the site by providing temporary heras fencing or wooden hoarding alongside the existing access road. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/172. Figure 2-6: Bective Site Location Slipway Construction Details of the proposed Slipway at this location are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/183 and 16009/193. Malone O Regan 5

9 The construction details will be similar to those outlined in Section with the following exceptions: It is not proposed to use Grasscrete and reinforced grass surfacing at this site Landscaping and Surfacing The sides of the Slipway will tie in with the existing river bank. The existing ground will be re-graded to tie in with the proposed new Slipway. It is proposed to retain the existing stone surfacing between the access point off the L4010 and the head of the proposed Slipway Drainage As described in Section there is no requirement for any drainage systems to be installed as part of the Slipway construction since the majority of proposed surfacing materials are permeable. Malone O Regan 6

10 1.3.3 Navan Old Bridge (MH_BS_005) Site Description The site is bounded by the River Boyne on its eastern boundary and by the R147 and a bridge on its western and southern boundaries respectively. The northern boundary of the site comprises of a green area between the R147 and the River Boyne. The proposed site is located on the outskirts of Navan town, with Navan town located to the north of the site and agricultural lands located to the south of the site Site Setup and Access The proposed Slipway site is located off the R147 road in Navan. As part of the construction of the Slipway the will be required to secure the site by providing temporary heras fencing or wooden hoarding at the entrance to the site off the R174. There is an existing stoned access between the R147 and the proposed Slipway location which provides a vehicle turning area for access to the Slipway. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/173. Figure 2-5: Navan Old Bridge Site Location Slipway Construction Details of the proposed Slipway at this location are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/184 and 16009/194. The construction details will be similar to those outlined in Section with the following exceptions: Malone O Regan 7

11 It is not proposed to use Grasscrete and reinforced grass surfacing at this site Landscaping and Surfacing The sides of the Slipway will tie in with the existing river bank. The existing ground will be re-graded to tie in with the proposed new Slipway. It is proposed to retain the existing stoned area between the access point off the R147 and the head of the proposed Slipway Drainage As described in Section there is no requirement for any drainage systems to be installed as part of the Slipway construction since the majority of proposed surfacing materials are permeable. Malone O Regan 8

12 1.3.4 Navan Centre (MH_BS_006) Site Description The site is located in the centre of Navan town and is bounded by the River Boyne on its northern boundary and by a Navan Town Council car park on its southern boundary. The site is bounded by the Boyne Ramparts Heritage Walk lands on its eastern and western boundaries Site Setup and Access The proposed Slipway site is located in close proximity to a public carpark in the centre of Navan town and will be accessed from the carpark via a narrow bridge and existing pathway which is surfaced with loose gravel material. The sharp crest on the bridge means that it will be difficult to drive larger trailers over the bridge. Indeed, there is evidence that the top of the bridge has been damaged by passing vehicles or their trailers. MOR consulted with the Civil Defence who advised that this bridge will afford sufficient access to the proposed Slipway. The proposed Slipway location is quite confined and there is significantly less space for vehicle turning than is the case at the other Slipway locations. The proposed Slipway is also located immediately adjacent to a public footpath. It is therefore likely that the footpath will need to be closed to public access for a period during the construction works. The closure of the footpath will need to be agreed with the Local Authority prior to commencement of the works. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/174. Figure 2-7: Navan Centre Site Location Malone O Regan 9

13 Slipway Construction Details of the proposed Slipway at this location are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/185 and 16009/195. The construction details will be similar to those outlined in Section with the following exceptions: It is not proposed to use Grasscrete and reinforced grass surfacing at this site. The construction of the Slipway at this location is extremely restricted due to the existing levels at the head of the proposed Slipway and the lack of available space to regrade the surface levels. As a result this Slipway will have a slope of approximately 17 degrees which is steeper than that the slope of 7-12 degrees which would normally be considered ideal (Ref. Guidance on Trail-Sail Association website, Landscaping and Surfacing The sides of the Slipway will tie in with the existing river bank. The existing ground will be re-graded to tie in with the proposed new Slipway. The existing gravel surfacing will be extended on the southern side of the public footpath in order to provide a turning area for vehicles using the Slipway. It is proposed to include additional linemarking in the carpark to prevent unauthorised vehicles parking in front of the bridge and obstructing access to the Slipway. It is also proposed to replace the existing bollards at the bridge, two of which are currently missing Drainage As described in Section there is no requirement for any drainage systems to be installed as part of the Slipway construction since the majority of proposed surfacing materials are permeable. Malone O Regan 10

14 1.3.5 Navan Weir (MH_BS_007) Site Description The proposed site is located on the outskirts of Navan town and is bounded by the River Boyne on its northern and western boundary. The site is bounded by the Boyne Ramparts Heritage Walk lands on its eastern and southern boundaries. Beyond the river and Boyne Ramparts Heritage Walk lands surrounding the site, the proposed site is surrounded by a mixture of residential and agricultural lands Site Setup and Access Access to the proposed Slipway location is by an existing 140m long narrow gravel road off the Boyne Road, which in turn runs into a 230m run of gravel canal towpath leading to the proposed site. There is no existing Slipway or vehicle turning area at this location. The existing access route is via an old masonry bridge across a canal. In order to access the Slipway vehicles will need to turn sharply to the left and southwestwards after crossing the bridge and turn 360 degrees before proceeding in a northeasterly direction along the existing towpath to the proposed Slipway site It is envisaged that construction of the new Slipway will require the towpath to be occasionally closed to public access. Access for construction traffic will need to managed locally and will need to be agreed with the Local Authority. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/175. Figure 2-4: Navan Weir Site Location Malone O Regan 11

15 Slipway Construction Details of the proposed Slipway at this location are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/186 and 16009/196. The construction details will be similar to those outlined in Section with the following exceptions: The existing river bank at this location slopes steeply down to the river. Formation of the proposed Slipway will require cutting in to the existing bank and locally lowering the levels. In order to minimise disruption to the existing bank, gabion baskets have been indicated along both sides of the proposed Slipway. These gabions will allow a step to be formed between the level of the Slipway at the river edge and the adjacent ground level. It is not proposed to use Grasscrete and reinforced grass surfacing at this site Landscaping and Surfacing The sides of the Slipway will be formed using stone-filled gabion baskets which will retain the existing bank. The existing ground around the Slipway and the access route to the Slipway will be re-graded to tie in with the proposed new Slipway. It is proposed to retain the existing gravel pathway access route from the public road to the Slipway and to provide a new vehicle turning area by laying additional hardcore at the head of the Slipway Drainage As described in Section there is no requirement for any drainage systems to be installed as part of the Slipway construction since the majority of proposed surfacing materials are permeable. Malone O Regan 12

16 1.3.6 Stackallen (MH_BS_008) Site Description The proposed site is located approximately 6km to the north-east of Navan town centre. The site is bounded by the River Boyne on its northern and western boundaries and by an unnamed public road on its southern boundary. The site is bounded by a derelict building and a small cluster of residential houses on its eastern boundary. Beyond the river and road boundaries surrounding the site, the proposed site is surrounded by predominantly agricultural lands Site Setup and Access This site is located off Local Road L in the Stackallen area. There is an existing stoned path to the River Boyne at this location. As part of the construction of the proposed Slipway the will be required to secure the site from the entrance off the public road to the Slipway location on the bank of the River Boyne. The existing stoned access path can be utilised by the for construction traffic. The will need to widen the existing stoned access route at the junction with the public road. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/170. Figure 2-2: Stackallen Site Location Slipway Construction Details of the proposed Slipway at this location are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/180 and 16009/190. Malone O Regan 13

17 The construction details will be similar to those outlined in Section with the following exceptions: It is not proposed to use Grasscrete and reinforced grass surfacing at this site Landscaping and Surfacing The sides of the Slipway will tie in with the existing river bank. The existing ground will be re-graded to tie in with the proposed new Slipway. It is proposed to retain the existing stoned access route from the public road to the proposed Slipway and to provide a vehicle turning area by laying additional hardcore at the head of the Slipway. It is proposed to install a timber edging to contain the hardcore surfacing at this site Drainage As described in Section there is no requirement for any drainage systems to be installed as part of the Slipway construction since the majority of proposed surfacing materials are permeable. Malone O Regan 14

18 1.3.7 Navan Blackwater (MH_BS_009) Site Description The proposed site is located in the centre of Navan town. The site is bounded to the south and the east by the River Blackwater, while to the north and west it is bounded by the Blackwater Park. Beyond the river and parkland boundaries surrounding the site, the proposed site is surrounded by a mixture of residential and commercial lands Site Setup and Access The proposed Slipway location is accessed through Blackwater Park. There is an existing tarmacadam pathway that loops around the Blackwater Park. The proposed access route to the Slipway is through this park. A new access route to the proposed Slipway will need to be constructed off the existing tarmacadam pathway. As access to this Slipway is through a public park, an agreement would need to be reached with the Local Authority to temporarily close off a section of the footpath within Blackwater Park to allow construction traffic to access the site. The extent of the site to be secured by the for the duration of the works would also need to be agreed with the Local Authority. Site specific details for the anticipated construction works site set-up are provided on Malone O Regan drawing 16009/176. Figure 2-3: Navan Blackwater Site Location Slipway Construction Details of the proposed Slipway at this location are indicated on Malone O Regan drawing 16009/100. Site specific details are provided on Malone O Regan drawings 16009/187 and 16009/197. Malone O Regan 15

19 The construction details will be similar to those outlined in Section with the following exceptions: It is not proposed to use Grasscrete and reinforced grass surfacing at this site Landscaping and Surfacing The sides of the Slipway will tie in with the existing river bank. The existing ground will be re-graded to tie in with the proposed new Slipway. It is proposed to construct an access route to the proposed Slipway using gravel surfacing. Additional gravel will also be laid in order to provide a turning area which will be set-back approximately 8m from the head of the Slipway. In order to prevent these new gravel areas from spreading under the weight of vehicular traffic, wooden sleepers will be installed around the perimeter of the gravel Drainage As described in Section there is no requirement for any drainage systems to be installed as part of the Slipway construction since the majority of proposed surfacing materials are permeable. Malone O Regan 16

20 2 WATER LEVELS Water levels were recorded at each of the 7 No. proposed Slipway sites by Absolute Precision surveyors as part of the topographical survey conducted for each site. Predicted water levels for a range of storm events were predicted based on the following sources of information: 1. OPW records 2. CFRAMS mapping 2.1 OPW RECORDS The mean recorded river level for the nearest gauging station to the proposed Slipway location on the day that the topographical survey was conducted was sourced from the Office of Public Works. Long-term statistical data from the Office of Public Works was also sourced for the nearest gauging station to the proposed Slipway location. The data sourced included the 1%, 5%, 95% and 99% duration percentiles for the recorded river levels based upon data derived for the period 1975 to The duration percentile river level is the river level that is equalled or exceeded for the given percentage of time. For example, the 1% river level percentile is the river level that is equalled or exceeded 1% of the time. The 1%, 5%, 95% and 99% duration percentile river levels were estimated for each of the 7 No. proposed sites based upon the following data: - Recorded water level on the day the topographical survey was conducted; - Mean river water level at the nearest gauging station to the proposed site sourced from the OPW; - Long-term statistical duration percentile river levels sourced from the OPW. The difference between the recorded river water level on the day the topographical survey was conducted and the mean river water level for the same day at the nearest weather station was calculated. This level difference was used to estimate the site specific 1%, 5%, 95% and 99% duration percentile river levels for each of the 7 No. proposed sites. 2.2 CFRAMS MAPPING In order to verify the river water levels which were calculated using the OPW data, Malone O Regan consulted the CFRAMS mapping. CFRAMS mapping gives predicted flood levels during 0.1%, 1% and 10% flood events on sections of the River Boyne and River Blackwater. 2.3 COMPARISON OF PREDICTED FLOOD LEVELS CFRAMS mapping was not available for the sites at Stackallen and Bective. For the remaining sites a comparison was made of the 1% flood level predicted using the OPW data and the CFRAMS maps. This comparison is shown in Table 2.1 below: Malone O Regan 17

21 Location Predicted 1% River Level OPW Data Predicted 1% River Level CFRAMS Mapping Difference (m) Navan Old Bridge m m 0.17 Navan Blackwater m m 0.10 Navan Centre m m 2.24 Navan Weir m m 1.69 Trim Castle m m 1.56 Table 2.1 Comparison of Predicted Flood Levels It can be seen that the flood levels calculated using the 2 different methods compare well for the Navan Old Bridge and Navan Blackwater sites. The corresponding Slipway section drawings for these sites have been prepared to show river levels calculated using the OPW data. At Navan Centre and Navan Weir, the 1% river levels calculated based on the CFRAMS mapping are substantially higher than the levels based on OPW data. It is noted that there is a Weir located between each of these sites and the nearest OPE gauging station. It is likely that the presence of this Weir has introduced a degree of inaccuracy into the levels predicted using the OPW data. The corresponding Slipway section drawings for these sites have therefore been prepared to show river levels calculated using the CFRAMS data. It is not clear why there is such a discrepancy in the two sets of levels at Trim Castle. Given the close proximity of the OPW gauging station to the site, similarities between the results could have been expected. The Slipway section for this site has been prepared to indicate river levels calculated using the OPW data. The 1% flood level as predicted from the CFRAMS mapping is also shown. It is important to note that the maximum flood levels are only provided for information and they have no bearing on the design of the Slipways. The level of the Slipway toe was set using the predicted low water level (the toe is positioned so that it will be submerged for 99% of the time). The top of the Slipway has been designed to tie into the surrounding ground level. No attempt has been made to build-up the top of the Slipway level to match the maximum predicted flood levels. Such measures would not improve the usability of the Slipway as the approach roads would still be submerged. Therefore the disparity in predicted 1% river levels using the OPW records and the CFRAMS mapping is not a cause for concern. Malone O Regan 18

22 3 HYDROLOGICAL ASSESSMENT Consideration has been given to how the proposed Slipways will affect the flow of water in the adjoining rivers. In particular, an assessment has been undertaken to determine the effect that construction of the Slipways will have on the channel conveyance capacity of the river. The Slipways have been designed to maintain to existing profile of the riverbank as far as is possible. The topographical surveys commissioned for each site were extended into the river at each location allowing for the accurate measurement of the existing bank profile at the proposed Slipway locations. This survey information has also been used to calculate the cross-sectional area of the river below the water line when considering the 1% river level. It is therefore possible to assess the loss of cross-sectional area as a result of the Slipway construction. The loss of cross-sectional area as a result of the proposed Slipway construction at each site is presented in Table 3.1 below. Location Estimated % Loss of Channel Cross- Section Based on 1% River Level Navan Old Bridge 4.8% Navan Blackwater 1.1% Navan Centre No loss of Cross-Section Navan Weir No loss of Cross-Section Trim Castle No loss of Cross-Section Stackallen 2.8% Bective No loss of Cross-Section Table 3.1 Loss in Cross-Sectional Area as a Result of Slipway Construction It can be seen that for 4 of the 7 sites, the proposed Slipway will not result in any loss of channel cross-sectional area. Of the remaining sites, the loss of cross-section area is marginal (in all cases less than 5%). It is considered that the proposed Slipways will not adversely impact on the flow in the river. It is also noted that the proposed Slipways are only 4.8m wide. The width of the Slipways has been kept as small as possible in order to reduce the impact on the river bank. Also the use of a profiled concrete mattress as opposed to a smooth concrete finish will ensure that the texture of the Slipway surface better replicates the natural riverbank, further minimising the impact on river flows. Malone O Regan 19

23 4 HEALTH AND SAFETY It is proposed to construct the new Slipways using both pre-cast and cast in-situ concrete elements. The toe of the Slipways will be constructed using a precast concrete beam and the ramped section of the Slipways will be constructed using a number of Dycel 150 articulated concrete mattresses. There are a number of Health and Safety benefits associated with the use of these precast concrete elements Slip Resistance The articulated concrete mattress units are formed with a series of voids which will offer improved slip-resistance over a typical cast in-situ concrete slab. The voids will be filled with gravel and the mattress underlain with a geotextile to prevent grass / weed growth. Malone O Regan discussed the proposed use of precast mattresses with Michael Fitzsimons of the Civil Defence. Mr Fitzsimons advised that precast mattresses had been used previously on the River Shannon and noted that from his discussions with several boat users the precast mattresses were viewed to have a greater slip resistance than an in-situ alternative. The upper section of the Slipway will be constructed using an in-situ concrete slab. The concrete will have a brushed finished to offer enhanced slip resistance Working in the River The use of precast concrete minimises the amount of work which needs to be completed in and adjacent to the river. The precast concrete toe beam and the articulated concrete mattress units can be lifted into place using an excavator thereby reducing the amount of works which need to be carried-out within the river compared to using in-situ concrete. In order to minimise the extent of works taking place within the river, it is proposed to restrict the works such that they will take place during the summer months when the river levels are expected to be at the lowest Design Risk Assessment A Design Risk Assessment is included in Appendix A. Malone O Regan 20

24 APPENDIX A - DESIGN RISK ASSESSMENT Malone O Regan

25 16009 Meath County Council Slipways Design Risk Assessment 1.0 Introduction In the following design risk assessments the risks are assessed on the basis of likelihood and severity in order to generate a risk rating as follows. Likelihood 0 No Risk 1 Highly Unlikely 2 Remote 3 Possible 4 Probable 5 Highly likely Severity 1 Negligible 2 Minor Injury 3 Major Injury 4 Severe Injury 5 Fatalities Risk Rating 1-4 Low Risk - Communicate 2.0 Persons Exposed 5-14 Medium Risk - Reduce - Communicate High Risk - Eliminate from design and / or construction - Reduce - Communicate : End-User: Maintenance: Public: Includes employees of the contractor and any sub-contractor engaged by the client for the construction or maintenance of the project Includes the client, their employees and the facilities operator Includes persons undertaking maintenance activities during the operation of the facility Includes any member of the public or visitor who could be exposed to hazards during the construction use or maintenance of the facility 3.0 Malone O Regan s Role in the Project Civil Structural Engineer Project Manager PSDP Building Services Engineer

26 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 1 Gradient of Boat Ramp Trips and slips by users of the boat ramps. Trips and slips by members of public. End-User Control Measures Implemented Dycel mattress proposed in place of Designer 9 Maintenance brushed concrete finish. During Public discussions with the Civil Defence it was agreed that this would offer improved slip resistance. Wherever possible the gradient of the slipway has been designed so as not to exceed 12 degrees. Warning signage to be installed. Further Control Measures Required Local Authority to ensure appropriate inspection and maintenance programme is implemented. End User responsible for using appropriate life jackets Designer Designer Local Authority End User MALONE O REGAN Consulting Engineers

27 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 2 Slips at toe of boat ramp Trips, slips and falls by users of the boat ramps. Trips, slips and falls by members of public. Risk of drowning End-User Control Measures Implemented Toe to be surrounded in large stone Designer 10 Maintenance riprap material to prevent erosion Public around toe. Warning signage to be installed. Life rings to be installed Designer Designer Further Control Measures Required Local Authority to ensure appropriate inspection and maintenance programme is implemented. In particular the LA should monitor for possible erosion of the stone at the toe of the ramp and place additional stone if required. End User responsible for using appropriate life jackets Local Authority End User MALONE O REGAN Consulting Engineers

28 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 3 Boat Operations Persons being struck by boat Persons injured while boarding or disembarking boats. End-User Control Measures Implemented Mooring bollards specified. Designer 10 Maintenance Public Belay rings structure. included in slipway Designer Risk of drowning New slipway provides stable surface to help facilitate boarding / disembarking boats. Life rings to be installed Designer Designer Further Control Measures Required Local Authority to ensure appropriate inspection and maintenance programme is implemented. End User responsible for using appropriate life jackets Local Authority End User MALONE O REGAN Consulting Engineers

29 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 4 Working in proximity to river Works contractor staff falling into river Risk of drowning. End-User Control Measures Implemented The design has sought to make use of Designer 10 Maintenance precast concrete elements over insitu Public concrete to minimise working time. Further Control Measures Required Works contractor to ensure all staff are given appropriate PPE including life jackets. to install temporary life rings MALONE O REGAN Consulting Engineers

30 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 5 Working in proximity to river (pollution) Risk of contamination of open water course by petrol spills, site debris, wet concrete etc. End-User Maintenance Public Control Measures Implemented The design has sought to make use of precast concrete elements over insitu concrete to minimise working time and to reduce risk of concrete spills into river. Designer 1 Gabion baskets specified at a number of locations to minimise the extent of disruptive works to the riverbank. Further Control Measures Required to provide construction method statement to show works are in accordance with best practice guides including: Control of Water Pollution from Construction Sites Guide to Good Practice (Ciria Guide SP156) Control of Water Pollution from Construction Sites Guidance for Consultants and s (Ciria Guide C532) Designer MALONE O REGAN Consulting Engineers

31 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 6 Vehicle Operations when slipway in use. End User struck by moving vehicle Member of public struck by moving vehicle End-User Control Measures Implemented The design for each slipway includes Designer 10 Maintenance adequate turning areas for a vehicle Public towing a trailer. Swept path analysis completed for all sites. Designer Further Control Measures Required Appropriate warning signage, safety cordons to be adopted by end user when slipways are in use. Vehicles to be guided when reversing. MALONE O REGAN Consulting Engineers

32 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 7 Vehicle operations during construction staff struck by moving vehicle Member of public struck by moving vehicle End-User Control Measures Implemented The design has sought to make use of Designer 10 Maintenance precast concrete elements over insitu Public concrete to minimise working time. Further Control Measures Required to provide traffic management plan for each site. Pedestrian routes and construction traffic routes shall be clearly separated and controlled. to erect adequate warning signage and site hoarding to protect members of public from works. Appropriately trained banksmen to be utilised when moving plant. All staff to wear appropriate PPE including hi-vis clothing. to ensure site is adequately lit at all times and to provide additional lighting if required. MALONE O REGAN Consulting Engineers

33 Design Risk Assessment Sheet Project: Meath County Council Slipways Analysed By: D. Weir Job No. : Date: Item No. Identified Hazards No Control Measures Associated Risks Population Exposed Control Measures Applied Risk Control Measures Person Responsible for Action Residual Risk Likelihood of Occurence Consequence of Occurence Risk Rating Risk Rating 8 Erection of precast concrete elements Working at height Objects falling Lifting, manual handling End-User Further Control Measures Required Lifting on precast units should be 5 Maintenance completed under the supervision of Public trained and qualified banksmen only. Erect appropriate warning signs. MALONE O REGAN Consulting Engineers