chapter 2 need for the proposed road development...roughan & o’donovan -fabermaunsell alliance...

Roughan & O’Donovan - FaberMaunsell Alliance N5 Westport to Turlough Road Project Consulting Engineers Environmental Impact Statement

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Chapter 2 Need for the Proposed Road Development

2.1 Introduction This chapter of the EIS outlines the need for the proposed N5 Westport to Turlough Road Development based on the deficiencies in the existing road network and identified future needs of the N5 corridor. It also provides a background to the proposed road development. The need for the proposed scheme is justified in the following sections: • Scheme Objectives and Needs • Existing Road Network • Character of the existing N5 • Traffic Volumes and Road Types • Do Minimum Scenario • Traffic Management Scenario • Do Something Scenario

2.2 Scheme Objectives and Needs In accordance with the “NRA Project Appraisal Guidelines” the provision of and need for improved transport systems is based on the following five criteria: • Economy • Safety • Environment • Accessibility and Social Inclusion • Integration The NRA Guidelines are themselves in compliance and in accordance with the Department of Finance’s “Guidelines on the Appraisal and Management of Capital Expenditure Proposals in the Public Sector” as well as the Department of Transport’s “Guidelines on a Common Appraisal Framework for Transport Projects and Programmes”. The proposed N5 Westport to Turlough Road Project comprises the provision of a new route to replace the existing N5 National Primary Route, from the N59 north of Westport Town to Turlough, east of Castlebar. Scheme objectives have been developed in accordance with the above criteria and are further described below.

2.2.1 Economy The proposed scheme will increase transport efficiency through a reduction in journey times over the length of the scheme. The proposed scheme will significantly alleviate the current traffic congestion in Castlebar. Westport will also experience a reduction in through traffic by the provision of the N5-N59 link road which will act as a northern bypass of the town. It is anticipated that a reduction in journey times over the length of the scheme will have a positive economic impact which will offset the initial construction costs of the scheme.


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The increased efficiency of the road network will deliver more reliable journey times for commuters, business and leisure users of this important tourist route, encouraging opportunities for work and tourism within and adjacent to the route corridor. The improved road network will have a positive impact in removing the potential restriction to business investment as a result of a lower standard road transportation network. The Cost Benefit Analysis for the proposed Scheme forecasts a saving of 12 million hours over the 30 year appraisal period. This analysis predicts that in the absence of the proposed scheme traffic delays will be equivalent to 45 people spending their lives sitting in vehicles 24/7 for the full 30 year appraisal period.

2.2.2 Safety The road currently has a poor safety record and therefore a reduction in accidents along the length of the existing route is one of the major objectives of the proposed scheme. The introduction of a more suitable road and cross section for the current and anticipated traffic flows, the reduction in junctions and access onto the road and more predictable journey times will all contribute to a safer road. Over the period from 2001 to 2012, Ireland has seen a rapid improvement in road safety, with the number of recorded fatalities reduced by 60.5%. Ireland is now 6th lowest out of 27 EU Member States in road deaths per million of population. These improved road safety conditions have been achieved through a series of measures forming part of the three Government Roads Safety Strategic Plans (1998-2002, 2004-2006 and 2007-2012). A cornerstone of all Road Safety Strategies is the contribution of engineering solutions (in addition to Education and Enforcement initiatives). Over the period of all three Road Safety Strategies, the National Roads Authority (NRA) have led the way in delivering a significantly enhanced inter-urban road network, in addition to a significant number of accident remedial schemes and bottleneck improvements. This continued improvement of the national road network has been an essential element in achieving the reduction in fatalities observed over the same period. Plate 2.1 below shows the level of fatalities per million vehicle kilometres in comparison to the cumulative spending on road infrastructure over the same period.



Source: Road Safety Authority (RSA) and NRA

Plate 2.1 Fatality Rate v Expenditure The Valuation of Accidents Accident benefits are generally accounted for in the economic appraisal of transport projects. Accident values are based on willingness to pay` to avoid accidents, with actual values based on studies of user risk acceptance. Whilst this may represent a theoretically sound economic indicator at an aggregate level, the consequences of any accident can lead to disproportionate impact on one small group of individuals. Whereas scheme appraisal is required to include actual costs of compensation / remediation for environmental or land acquisition impacts, it is noted that the valuation of accidents only values the risk that accidents may occur – this is likely to be significantly less than the value of the impact to those impacted. As such, the valuation of accidents, and hence the level of accident benefits, can sometimes be lost in the numerics of a full economic appraisal. It is for this reason that a more qualitative appraisal of road safety impacts is appropriate. Although accident benefits will continue to be captured in the economic appraisal through the standard approach, a further discussion of the impact on individuals is presented below. Observed Accident Information for the N5 Examining the recent accident history along the N5 corridor, the data shows quite a significant accident history. Over the period from 1996 to 2011, it is estimated that a total of approximately 409 persons have been killed or injured along the N5 between Westport and Turlough as indicated in Table 2.1. This total also includes for the effect of under-reporting of non-fatal injuries that has been observed in Ireland. This equates to a rate of approximately 1 fatality per annum along the corridor, with 3 serious injuries and approximately 22 minor injuries.



Table 2.1 Observed Casualties per Annum (1996-2011)*

Severity Observed Casualties*

Under-Reporting Factor Casualties Casualty Per

Annum Fatal 11 1 11 0.69

Serious 32 1.5 48 3.0 Minor 117 3 351 22.0

Source: Road Safety Authority * Observed accident data has not been included along the N5 through Westport Town.

Plate 2.2 Observed Casualty Map (1996-2011) On closer examination, it is clear that the clusters of fatal accidents as illustrated in Plate 2.2 occur between Westport and Castlebar (where the road alignment is particularly poor with frequent junctions at local roads, accesses and properties with road frontage), and between Castlebar and Turlough where a combination of direct accesses, overtaking activity, higher speeds and priority junctions increase the general level of risk. Do-Minimum Accident Forecasts for the N5 As traffic flow increases on the N5 in future years, the number of accidents will increase in proportion. The traffic modelling suggests that traffic growth over the 30-years of the appraisal will be in the region of 24%. As such, the number of fatalities per annum would be expected to grow from the current 0.63 to 0.78 fatalities per annum by 2048. The number of serious injuries will increase from 3.0 to 3.7, whilst there will be close to 27 minor injuries per annum. Over the 30-year life of the scheme, the total road safety statistics are likely to be: • 22 fatalities • 103 serious injuries; and • 750 minor injuries



This is clearly a substantial impact with quite notable consequences for those individuals and their communities. The Impact of Road Improvements The development of the proposed scheme and subsequent transfer of traffic from a single carriageway to a Type 2 Dual Carriageway will reduce the number and severity of accidents along the N5 corridor by: • Removing the likelihood of head on collisions; • Allowing safe overtaking; • Ensuring that pedestrians, cyclists and agricultural vehicles can use routes that

are away from the strategic road network; • Removing right turning conflicts (compact grade separation, roundabouts and

left in/out only junctions proposed); • Improving visibility and general road conditions; and • Improving the safety of the roadside in the event of single-vehicle collisions. For single-vehicle accidents, data from the Road Safety Authority (RSA) as illustrated in Table 2.2 shows that collisions with roadside objects (e.g. walls, ditches, bollards and trees) account for approximately 75% of fatalities. The provision of safety barriers and careful location of roadside equipment will significantly reduce the risk of such accidents, and is a major contributor to the reduction in injuries on newer roads. Table 2.2 Single Vehicle Collisions (not involving pedestrians) Classified

by Type (2011)

Source – Road Safety Authority “Road Collision Facts 2009”

For multiple vehicle accidents, head-on collisions remain the main classification. The provision of a type 2 dual carriageway will almost eliminate such accidents, due to the provision of a central segregation barrier. In 2011, head-on collisions accounted for 15% of all fatal accidents, or 30% of all multiple-vehicle collisions. Clearly, the elimination of such accidents on the N5 will account for a substantial quantum of the expected reduction in injuries.



Source – Road Safety Authority “Road Collision Facts 2011”

Plate 2.3 Primary Collision Type (2011) and frequency (%) The impact of the roads programme (in addition to other initiatives within the Road Safety Strategies) over the period from 2001 to 2011 can be seen from Plate 2.4 below, which shows a notable rebalancing in the number of head-on conflicts over that period. The data shows a notable reduction in the number of fatalities across all categories, with the highest absolute reduction occurring for pedestrian and head-on collisions. The number of single vehicle accidents has also reduced substantially.

Plate 2.4 Fatalities by Collision Type Potential benefit of the Proposed Scheme The proposed scheme will improve safety as a result of two major responses as follows: • Traffic using the N5 will be provided with a safer route, leading to a substantial

reduction in the number of accidents along that corridor; and



• Traffic on other corridors (e.g. alternative local, regional or national secondary roads) will re-route to instead follow the N5 corridor. As such, traffic flows on alternative routes will reduce, thereby leading to a reduction in accidents on those other routes. This can often lead to a strong improvement in the casualty rate given the relatively poor safety record (expressed as a function of the traffic volumes) on some non-national routes.

The accident impacts of any scheme are calculated within the COBA programme, which applies an accident rate to each road in the modelled network, and calculates the total number and severity of accidents on each road as a function of the anticipated traffic volume. The network total is calculated as a sum of all accidents on each road, accumulated over the 30-year appraisal period. For the current scheme, the Cost Benefit Analysis predicts a reduction in accidents along the N5 and on all other road in the vicinity of the scheme as follows: • A reduction of 35 fatalities • A reduction of 121 serious injuries; and • A reduction of 1229 minor injuries This reduction in injuries is substantial and demonstrates the scale of the benefit that can be associated with the proposed scheme. The reduction in fatalities will be approximately 1 per year. Fatal injuries on this scale can have devastating impact on communities, particularly in the case where multiple fatalities occur. In such cases, it is considered that the willingness to pay approach does not fully represent the scale of cost imposed on those who are impacted by such events. In the case of serious and minor injuries, a reduction of 1350, or approximately 45 per annum is expected. Although injuries are less severe, this number is nevertheless significant. It is noted that any injuries on this scale involving public service vehicles (rail or bus) would attract substantial consequential investment in mitigation measures and other safety enhancements. As such, the significant of this scale of benefit should not be understated. The development of the N5 project is needed to address a notable road safety deficiency along the existing N5 between Westport and Turlough. The proposed scheme would achieve this through provision of a safer alignment which would virtually eliminate head-on collisions, significantly reduce the severity of single vehicle accidents, ensure alternative routes are available for vulnerable road users, and lead to safety improvements for those who would continue to use existing roads by reducing traffic volumes on those roads. The scheme would lead to a saving of approximately 35 lives over the period from 2018-2048 with significant knock-on benefits to communities. In addition, over 1,350 non-fatal injuries could be avoided. These are significant impacts which, it is considered, are not fully reflected through the current willingness-to-pay methodology employed in project appraisal. As such, these impacts should also be considered qualitatively in the Project Appraisal.



2.2.3 Environment The proposed scheme will enhance environmental quality in the towns of Castlebar and Westport and along the existing route of the N5 with its extensive ribbon/housing development. Although it is anticipated that the construction of the proposed scheme will have an impact on the receiving environment, the reductions in traffic though towns and villages along the route will be of benefit to inhabitants through an improvement in air quality, noise and community severance which are discussed in more detail in the respective chapters of the EIS. The selected route seeks to minimise impact upon the existing environment wherever possible through avoidance of sensitive areas. Where this is not feasible mitigation measures will be put in place. It is anticipated that there will be an improvement in air quality within the towns as a result of the removal of through traffic. This coupled with reduced congestion within the towns and a decrease in stop start driving, with more constant driving conditions, will result in an overall improvement in air quality. Due to the reduction in vehicles and improved flows through the affected towns and villages there will be an improvement in noise and vibration for the many properties close to the existing main road. Some properties that will be located close to the proposed road will be impacted by increased noise levels. For these affected properties mitigation measures will be implemented as necessary through the construction of noise barriers and noise bunds to limit the impacts of noise and vibration. Currently most of the surface water on the N5 is discharged into the receiving environment un-attenuated and untreated. All road drainage from the new main alignment will be collected by a combination of piped drainage systems, ditches and swales, and discharged through stormwater retention ponds. In terms of water quality improvement a combination of swales, reed filtration beds will be utilised prior to the water discharging to any existing watercourses or groundwater. With traffic transferring to the new route a high proportion of spillages will benefit from being captured and treated before discharging to the receiving environment. The scheme will terminate close to the River Moy Special Area of Conservation (SAC) but does not extend into the SAC and there will be no direct effects on this site. Mitigation measures as described in the EIS will be fully implemented, so as to not adversely affect the integrity of the River Moy SAC.

2.2.4 Accessibility (and Social Inclusion) Accessibility is divided into impact on vulnerable groups and impact on deprived geographic areas. The design has been prepared with the objective of avoiding any impact on vulnerable groups and at the same time meeting the objectives of - The National Development Plan 2007 - 2013, The National Spatial Strategy and Regional, County and Local Development Plans in their aims to revitalise the Western Region. Parts of County Mayo, including the rural areas outside Castlebar and Westport, are recognised as an area of social exclusion through the CLÁR programme (Programme for the Revitalisation of Rural Areas). The proposed scheme will provide improved access to the County Mayo CLÁR area in general and specifically



to the rural areas around Westport and Castlebar which will be directly serviced by this proposed road scheme. The reduction in through traffic flows in Castlebar and Westport towns will address the constraint to economic development currently caused by peak hour congestion. The traffic reduction will decrease severance of the local town community with particular benefit to vulnerable groups such as school children, older people and people with disabilities, supporting the government objectives for the reduction of social exclusion as set out in the National Anti Poverty Strategy (2002). The reduction in traffic along the existing N5 between Westport and Castlebar will result in a reduction in severance to the Islandeady community.

2.2.5 Integration The completion of the scheme is a stated objective of the National Development Plan. It is consistent with local policy documents, most notably the Mayo County Development Plan and national policy documents, in particular Smarter Travel – A Sustainable Transport Future. Regional Planning The Regional Planning Guidelines for the West Region 2010-2022 contain the following policies for roads infrastructure; (i) Support the National Roads Authority investment to remedy deficiencies

generally in the roads network, minimising environmental impact. (ii) Support the NRA programme of works on the national routes throughout the

region, minimising environmental impact. (iii) National roads and strategic regional roads should be protected from

inappropriate development, to ensure that they are not overloaded with local road traffic more appropriately served by the local road network and which would undermine the strategic transport function of national roads, including interchanges, minimising environmental impact.

The proposed scheme will provide improved access from the midlands region to the Western region in a manner consistent with all relevant national and local polices. Smarter Travel: A Sustainable Transport Future Smarter Travel, A Sustainable Transport Future, presents a transport policy framework for Ireland covering the period up to 2020. The policy, launched by the Department of Transport in 2009, sets out a vision, goals and targets to be achieved, and outlines 49 actions that form the basis of achieving a more sustainable transport future. Whilst the document does not present a definitive list of requirements with respect to new infrastructure, it is nevertheless necessary to understand the compatibility of the proposed scheme with the actions set out in the policy document. Actions are classed under 4 main categories which are reviewed below: Actions to reduce distance travelled by private car which includes focusing population growth in areas of employment and to encourage people to live in close proximity to places of employment This group of actions recognises the need to focus population and employment in a way that will minimise the potential for excessive transport demand. This will be achieved through consolidation of future growth in residential, commercial and retail



development within existing settlements. The provision of significant increases in transport infrastructure in urban areas can influence development patterns, leading to a risk of subsequent sprawl, which threatens the consolidation model. Castlebar has been identified as a linked hub within the National Spatial Strategy and offers the potential for significant growth in population and commercial activity – indeed the proposed N5 route bypassing Castlebar is key to supporting inward investment to the area. During the route selection process, it was recognised that a major road traversing much closer to the outskirts of the town could lead to additional challenges with delivering a sustainable planning model. In response, the proposed alignment of the N5 Castlebar Bypass was located some distance from the town centre and access restricted to a number of key strategic locations. As such, the proposed N5 will support future growth in Westport and Castlebar, but without unduly influencing the demand for travel or pattern of local development or car use within each town. Actions aimed at ensuring that alternatives to the car are more widely available, mainly through a radically improved public transport service and through investment in cycling and walking, The discussion of public transport within Smarter Travel distinguishes between Significant Urban Areas and Rural Areas. For public transport, the focus in urban areas is a transfer from car use to fast and frequent public transport services in order to reduce congestion and emissions in densely populated areas. For rural areas, public transport attracts less demand as a result of the dispersed population, and hence there is limited congestion or environmental benefit to be realised. Instead, rural services are focused more on filling a social need, providing access for those who do not have access to private means of transport. The proposed scheme will reduce the cost of providing rural transport services along the N5 corridor as a result of the increased accessibility to Westport and Castlebar, and the reduced congestion within those towns. In addition, it will reduce the cost of providing inter-urban bus services which connect Castlebar and Westport with the midlands and Dublin. Local bus services between Castlebar and Westport will continue to use the existing N5 and thereby continue to service the rural communities along the existing road. The potential for cycling and walking is most relevant within the urban areas of Castlebar and Westport. As mentioned above, the proposed N5 will support the consolidation of development in those towns, in addition to improving the walking and cycling conditions by means of removing significant volumes of through-traffic. As such, those actions are also fully supported by the proposed scheme. Actions aimed at improving the fuel efficiency of motorised transport through improved fleet structure, energy efficient driving and alternative technologies Actions under this heading are more related to vehicles and driving methods, and are therefore not particularly relevant to the proposed scheme. The removal of traffic from Castlebar and Westport will lead to a reduction in stop start motoring for vehicles transferring to the new road and less idling time for those remaining in the urban areas and therefore greater fuel efficiency.



Actions aimed at strengthening institutional arrangements to deliver the targets. The establishment of Demonstration Towns, formulation of the National Sustainable Travel Office and publication of the Sustainable Travel and Transport Bill are included in this heading. The Smarter Travel document sets a target of reducing work-related commuting by car from 65% to 45% over the life of the policy, with no significant increase in vehicle km of the national car fleet between 2006 and 2020. It is important to note that the document sets these as targets which subsequent initiatives should strive to achieve. In other words, the Smarter Travel policy document alone will not lead to those targets being met, and hence the targets presented therein cannot be used as the basis for forecasting of future travel demand. As actions are progressed into projects and subsequently delivered, their impact on travel demand can be quantified and incorporated into future analyses. The proposed scheme will therefore support Smarter Travel through improving accessibility for rural public transport services, and improving the potential for strong growth in walking and cycling within the towns that are bypassed. Its alignment will support consolidation of development within Castlebar and it will support more efficient driving through the provision of higher quality infrastructure.

2.3 Existing Road Network

2.3.1 The Existing N5 and National Roads The existing N5 National Primary route is a single carriageway road that extends from Westport at its western most end, through to the intersection with the N4 National Primary route at Longford. The extent of the N5 under consideration extends from Westport to east of the Village of Turlough in County Mayo and is shown in Plate 2.5 and Figure 2.1 in Volume 3.

Plate 2.5 Location of N5 Westport to Turlough Road Project



2.3.2 Existing N5 and N59 – Westport This element of the existing route is shown on Plate 2.6 and in Figure 2.2 and 2.3 in Volume 3.

Plate 2.6 Existing N5 and N59 – Westport The existing N5 route commences within the town of Westport at the intersection with the N59 at the Octagon. The N59 itself is a National Secondary route which commences south of Sligo Town near Ballysadare and runs west into County Mayo through Ballina and proceeds via Bangor and Newport to Westport. It then runs in a southerly direction via Clifden towards Galway City. The N59 is connected to the N5 in Westport Town centre and provides a direct link with Newport which is situated approximately 12 km north of Westport. From the N59 intersection with the N5 at the Octagon the existing N5 heads in a northerly direction along James Street and the North Mall before continuing along Castlebar Street towards the Lodge Road in the townland of Carrowbeg. The N5 also connects to the R330 Regional Road along the North Mall, with a further 7 junctions with local roads as it heads east from the North Mall to the Lodge Road on the eastern edge of Westport.

2.3.3 Existing N5 Westport to Castlebar The existing N5 progresses eastward from the Lodge Road in Westport to Castlebar along a length of approximately 14 km passing through 60 junctions with intersecting local roads. Leaving Westport the existing N5 heads eastward passing to the south of the townlands of Drummindoo and Sheean and continues in the direction of Castlebar, passing Islandeady Lough and Village to the north and the Castlebar - Westport rail line to the south. Towards the southern end of Lough Lannagh the road

N59 to Galway via Clifden

N59 to Sligo via Newport

N5 to Castlebar

R330 to Ballinrobe



turns to head north-west into the town of Castlebar. This section of the existing route is shown on Plate 2.7 and Figure 2.3 to 2.9 in Volume 3.

Plate 2.7 Existing N5 Westport to Castlebar

2.3.4 Existing N5 Castlebar This section of the existing N5 route is shown on Plate 2.8 below. The existing N5 route runs through Castlebar where it intersects further Local, Regional and National Roads. To the west of the town the N5 passes though a traffic calmed area with parallel cycle tracks before intersecting the R310 Regional Road (Pontoon Road) at the first of three roundabouts within the town along the existing N5. Heading in an easterly direction through the town the N5 intersects the National Secondary N60 at the next roundabout. The N60 route travels in a south-easterly direction through the localities of Kilkenny and Breaghwy and links Castlebar to Roscommon through Claremorris, Ballyhaunis and Castlerea. A short distance south of the N5/N60 roundabout the N84 intersects with the N60. The N84 runs in a northerly direction from Galway through Ballinrobe towards Castlebar where it joins the N60 at a signalised junction in Castlebar Town. On the east edge of Castlebar a third roundabout is formed with the R373 Regional route which links to the town centre of Castlebar to the north and to the N60 at a roundabout 1.5 kilometres to the south. East of this roundabout is a traffic calming gateway. There are 7 local road junctions onto the N5 between the three roundabouts along the distributor road.



Plate 2.8 Existing N5 Castlebar

2.3.5 N5 East of Castlebar From Castlebar the section of the existing N5 under consideration heads east towards the townlands of Knockanour, Gortnafolla and Drumdaff, through the termination of the proposed scheme east of the village and townland of Turlough. This section of the existing route is shown on Plate 2.9 and Figure 2.15 to 2.18 in Volume 3.

Plate 2.9 N5 East of Castlebar

R311

N60

N84 N5 to Westport

R373

R310

Humbert Way

Lawn Road

N5 to Longford

N5 to Castlebar

N5 to Longford



This section follows an upgraded section of the N5 which was constructed between 1988 and 1990. The former N5 (L-1719 – Turlough Road) runs parallel and to the north of the present N5 along this length. The current N5 passes between Turlough House and Park - site of The National Museum of Country Life, to the north, and Turlough Church of Ireland Church and its cemetery to the south. This section of the N5 includes 10 junctions with intersecting local roads. Progressing eastwards beyond the scheme termination at Turlough the N5 continues towards the villages of Ballyvary and Bohola onward via the bypasses of Swinford and Charlestown before continuing on towards Longford where the N5 joins the N4 Dublin – Sligo route.

2.3.6 Existing Regional Roads There are four Regional Roads that intersect the existing N5 route between Westport and Turlough, as follows: • R330: Westport to Partry – intersects the existing N5 at the Mall within

Westport at its northern end before extending to Partry, forming an intersection with the N84 approximately 21 kilometres to the south east.

• R310: Castlebar to Ballina via Pontoon – from a junction with the existing N5 at the most westerly roundabout along the N5 within Castlebar the R310 progresses north east and intersects the N26 to the south of Ballina.

• R311: Castlebar to Newport - forms a junctions with the R310, N60 and N5 within Castlebar and extends north west towards Newport where it forms a junction with the N59.

• R373: Castlebar to the N60 – provides a links to the town centre of Castlebar at its northern end and to the N60 at a roundabout 1.5 kilometres to the south east while crossing the N5 at the eastern-most roundabout along the N5 within Castlebar.

2.3.7 Local Roads There are numerous local roads along the length of the Scheme. These roads generally have cross-sections ranging from 3.0 metres – 7.0 metres in width with limited verges and no hard shoulders. There are a total of 84 local road junctions that intersect the route of the existing N5 between Westport and Turlough. These roads vary in function from local connector roads down to access roads serving only two or three individual properties.

2.4 Character of Existing N5

2.4.1 Existing N5 and N59 – Westport On the approaches to Westport and within the town both the N5 and N59 perform the dual functions of a national road and an urban street(s). Throughout this section a mixture of established commercial, tourist, social and residential properties front directly onto the road on both sides. Within the town centre the existing road consists of a number of one way streets between signal controlled junctions, with footpaths occupying whatever limited verge width is available. The speed limit is 50kph. Westport is a picturesque town and popular tourist destination, with the river Carrowbeg running through the centre immediately adjacent to the N5. The combination of local and through traffic results in significant congestion on a daily basis, detracting from the picturesque nature of the town and constraining future development. Plates 2.10 and 2.11 show the current congestion to the east of and within Westport.



Plate 2.10 N5 East of Westport

Plate 2.11 N5 Through Westport



2.4.2 Existing N5 Westport to Castlebar The existing N5 from the Lodge Road on the eastern edge of Westport to the traffic calming on the approach to Castlebar has generally poor geometry with significant road frontage to commercial and residential properties, accesses and junctions along its length. This section is approximately 14 kilometres in length with a speed limit of 100kph. It carries a diverse mix of traffic travelling at different speeds, including: • Commuters in cars • Commercial vehicles • Public transport vehicles • A dozen or more school bus routes • Agricultural vehicles • Tourist traffic, including cyclists This mix of through traffic and local pick up and drop off manoeuvres at the many junctions and accesses, without the benefit of either overtaking of pull in facilities, leads to long tailbacks and at times unsafe conditions for vulnerable road users. Road Geometry and Road Cross Sections The existing road is a single carriageway road with varying cross section, with the lane widths varying between 2.6 and 3.5 metres and hard shoulder widths varying between 0 and 3 metres. Similarly the verge width varies considerably along this length of the existing N5 from 0 to 3 metres in general, with wider sections at certain locations. Along the 14km between Westport and Castlebar only 2km on the edge of Westport and a 0.5km length midway between the two towns have full hard shoulders. The remaining 80% of this length of road has limited hard strips. In accordance with the current design standard NRA TD 27, the road would have a cross-section approaching that of a Type 2 Reduced Single Carriageway, due to the lack of hard shoulders, although significant lengths would not meet the lane width or verge width required for this minimum National Primary Road cross-section. Junctions and Access Along this length of road there are 60 junctions with existing local roads and access roads. In addition there are individual accesses and junctions to the following: • Houses – 198 • Combined house and field access – 3 • Fields Access – 99 • Access to businesses 26 This is equivalent to 27 junctions and accesses per kilometre, where more than 9 per kilometre would be considered as ‘High’ in accordance with the design standard NRA TD 9, Clause 1.4. Many of these junction and accesses do not currently provide sufficient visibility to meet current safety standards for the posted speed of 100kph. Furthermore, all of these junctions are simple junctions with no provision for right turning vehicles to stop without obstructing the flow on the National Primary Road. In accordance with the current design standard NRA TD 41-42 ghost island junctions should be provided where the flow on the local road exceed 300 vehicles per day. While the vast majority of these junctions and accesses have flows below this threshold, at least ten of these junctions are carrying flows that exceed this threshold, adding to the delays and poor safety record along this section of the N5. Plate 2.12 shows traffic on the Existing N5 between Westport and Castlebar at the L-18133



Claggarnagh East Road and Plate 2.13 shows further slow moving traffic on the existing N5.

Plate 2.12 Traffic on the Existing N5 between Westport and Castlebar

Plate 2.13 Slow Moving Traffic causing delays Local Constraints to On-Line Improvement With 198 house accesses and 26 businesses fronting onto the existing N5 the opportunities for on-line improvement are severely constrained. Numerous farm accesses and agricultural buildings are also located along this length. Other constraints limiting on-line improvements to the existing road are: • The Westport to Castlebar railway line to the south of the existing N5 between

Kilbree Lower and Dooleague • The National School to the south of the N5 at Islandeady • ESB Substation in Knockranny

With the existing narrow cross section, numerous tight bends, existing constraints and high levels of road frontage and access, any on-line upgrade would require extensive residential property acquisition, impacts on businesses that have direct frontage to the road, and may require the relocation of the ESB and School facilities.



Pedestrians and Cycle Facilities There are no designated cycle or pedestrian facilities along this length of the existing N5 except on the final approach to Castlebar. The limited hard shoulders and verges dictate that any pedestrians or cyclists would need to use the trafficked lanes along the large majority of this length of the route. The high volumes of vehicles using this route, often travelling at high speeds outside of peak journey periods, make this length particularly unattractive and potentially unsafe for non-motorised users.

2.4.3 Existing N5 through Castlebar Town Within Castlebar the existing N5 forms an inner bypass/distributor road to the south of the town centre, bounded by residential and commercial development on both sides. The 60kph speed restriction associated with the existing N5 passing through the urban area extends from the gateways to the east and west of the town over a length of approximately 4 kilometres. The speed restriction applies from the townland of Ballymacrah approximately 1.8 kilometre to the west of the N5 / R310 roundabout in the townland of Knockaphunta. Between the N5 / R310 roundabout and the N5 / R373 roundabout in the townland of Moneenbradagh the speed restriction reduces to 50kph. The speed restriction then increases to 60kph again between the N5/R373 roundabout and the urban gateway 200m east of the roundabout. The section of N5 between R310 and N60 roundabouts is referred to as Humbert Way, while the N5 between the N60 and the R373 roundabouts is referred to as Lawn Road. The combination of local and through traffic results in significant congestion on a daily basis, constraining the ability of Castlebar to function and develop in its role as the regional hub within the National Spatial Strategy. The necessary imposition of the 50kph and 60kph speed restrictions over a 4 km length of the national primary route inevitably compromises the National Road Authority’s target minimum level of service D for through traffic, which seeks to deliver an average speed of 80kph for inter-urban journeys. This restriction exists throughout the day, and is exacerbated by further delays caused by congestion in the peak periods. As such Castlebar acts as a barrier to the development of Westport and the surrounding areas further west. Road Geometry and Road Cross Sections This section of inner bypass/distributor road was constructed on a new alignment between 1992 and 1993. The road has a single carriageway cross section of varying width with sections of road that widen to two lanes on approach to the three roundabouts returning to a single lane after passing through the roundabouts. The road has no hard strip or hard shoulder along this section and is kerbed from the approach to the R310 Roundabout for the entire length of the existing N5 through the town to the R373 roundabout at the east of the town. The verge width varies throughout this length from 1.8 to 3 metres and wider at certain locations. The verge incorporates a paved footpath of between 1.8 metres and 2 metres over the majority of this length of road. Junctions and Access As described above the existing N5 within Castlebar intersects the R310, N60 and R373 at a series of three roundabouts. All three roundabouts suffer from capacity constraints and result in congestion on a daily basis during peak hours. See Plate 2.14 below.



Plate 2.14 Congestion at N60 Junction in Castlebar Apart from the major roundabout junctions formed with the National Secondary Routes and Regional Routes there are 7 local road junctions between the roundabouts. In addition there are the following direct accesses to businesses and houses onto the N5 between the roundabouts to the east and west of the town: • Shared Access Roads - 7 • Access to businesses - 2 • Houses - 5 Local Constraints to On-Line Improvement Significant urban development, on-line and at the 3 major roundabout junctions, all constrain further development of the road and junctions. Businesses, existing house and property frontage provides the largest constraint. The most significant constraints at each of the major roundabout junctions are as follows: • R310 - Buildings for the Mayo Mental Health Service (An Coillin) to the east

along with a number a nearby houses and apartments to the west. • N60 – Existing houses to the northeast of the roundabout and businesses to

the southwest including a car dealership. • R373 – A service station to the west and a number of businesses to the east. Pedestrians and Cycle facilities Pedestrian facilities are provided on both sides of the carriageway through the town between the R310 and R373 Roundabouts in the form of footpaths within the raised verges. Signalised pedestrian crossing points are provided along with pedestrian crossing points at the roundabouts. A combination of on-road and off-road cycle tracks exist from the western approach to the town through to the R373 roundabout at the east of the town. East of the R373 roundabout the N5 has hard shoulders which are utilised by both pedestrians and cyclists.

2.4.4 Existing N5 Castlebar to Turlough This section of the existing N5 extends from the urban gateway to the east of the N5 / R373 Roundabout in Castlebar through to Turlough, terminating 800 metres east of the Castlebar River crossing, a total length of approximately 6.5 kilometres. This



section of the N5 was upgraded between 1988 and 1990 and follows what was then a new, largely greenfield alignment. Road Geometry and Road Cross Section The existing road is a single carriageway road with generous lane and hard shoulder widths. The verge width varies from 0.5 metres upwards. An analysis of the average road cross section is summarised as follows: • Carriageway 8.0 metres (2 x 4.0 metre lanes) • Hard shoulder(s) 2.5 – 3.2 metres • Verge 0.5 metres min In terms of geometry this section is generally straight with large radius curves and easy gradients. Junctions and Access Direct accesses and junctions onto the current road are limited to field accesses, a single property access and 10 at-grade junctions formed with local roads. While these junctions and accesses are not fully compliant with current design standards they are generally of an adequate standard with regard to visibility having been designed as part of the 1988-1990 upgrade. However these junctions include four cross roads and some severely skewed junctions, both arrangements that are no longer considered appropriate on National Roads. Local Constraints to On-Line Improvement There are no major constraints that prevent further on-line improvement of this section of the road. The most significant constraints along this length include: • The Castlebar River running to the north of the existing N5 carriageway and

bridged over in the townland of Gortnafolla, east of Turlough. • Turlough House, home to the National Museum of Ireland - Country Life, to the

north of the N5. • Church of Ireland in the townland of Gortnafolla, south of the N5. • Bord Gáis mains in the hard shoulder and a treated wastewater main in the

verge of the westbound carriageway. Pedestrians and Cycle Facilities No specific pedestrian or cycle facilities are provided along this length of the carriageway, however the entire length has a wide hard shoulder that is utilised by pedestrians and cyclists.

2.5 Traffic Volumes and Road Types

2.5.1 Traffic Volumes This section of the N5 carries both long distance traffic from the east of the country to Castlebar and Westport and significant regional inter-urban traffic flows between Castlebar, Westport, Ballina, Kiltimagh and Newport with the section through Castlebar providing the regional connections to Claremorris, Ballinrobe and beyond. The capacity of the existing infrastructure is not sufficient to meet these demands resulting in significant traffic congestion, particularly at peak hours.



Chapter 5 describes in detail the traffic modelling exercise that has been undertaken to inform the design process. During the development of the traffic model the flows have been identified along the route of the existing N5 and associated routes that connect to the N5. The traffic volumes were identified for the Base Year (2013), being the date of calibration of the model against existing flows, a potential Opening Year (2018), the earliest date that the proposed road improvement scheme could be delivered, and what is referred to as the Design Year (2033), 15 years after the opening of any such road improvement. Initially the existing and predicted traffic flows along the N5 and associated routes were assessed for each of these years for a situation where no new road scheme was proposed (Do-Minimum Scenario). Based on the figures from the traffic model for the scheme, the traffic flow figures in AADT for the major routes are shown in Table 2.3. Table 2.3 Existing N5 Traffic Flows (Do-Minimum Scenario)

Road Base Year 2013 (AADT)

Opening Year 2018 (AADT)

Design Year 2033 (AADT)

Existing N5 Westport Road (Westport to Castlebar, rural) 11,400 12,000 13,700

Existing N5 Westport Road (approaching Castlebar) 9,700 10,300 11,600

Existing N5 Humbert Way (310 to N60 Junction) 14,800 15,300 16,000

Existing N5 Lawn Road (N60 to R373 Junction) 14,400 15,000 16,700

Existing N5 Turlough Road (East of Castlebar) 11,200 11,800 13,400

N84 at Aghadrinagh 6,300 6,700 7,900 N60 at Kilkenny 9,900 10,500 11,900

2.5.2 Carriageway Types The available road types for the development of new road schemes within Ireland are as detailed in Table 2.4 extracted from – NRA TD 9 Table 6/1: Recommended Rural Road Layouts.



Table 2.4 NRA TD 9 Table 6/1: Recommended Rural Road Layouts

*Note: In accordance with TD 10 the Type 3 Dual Carriageway is considered appropriate for use on national road schemes in rural areas where the traffic flow in the design year is between about 11,600 and 14,000 AADT. However, the road type is intended mainly where a road is to be upgraded on-line, to increase the capacity of the existing road. It is therefore has not considered for sections of offline alignment. In addition to defining the road types available to designers, along with the predicted traffic capacity that each road type layout is capable of carrying while providing a suitable Level of Service, NRA TD 9 Table 6/1 indicates the required and minimum acceptable requirements in relation to treatment of junctions, access and edge treatment. The approximate capacity of each road type is given in terms of the two-way Annual Average Daily Traffic (AADT). The AADTs listed are the estimate traffic flows at which drivers would experience ‘Level of Service D’, providing a minimum average journey speed of 80kph on Single Carriageways and 90kph on Dual Carriageways. Based on the recommendations of NRA TD 9, the estimate traffic flows from Westport through to Turlough fall within the bounds of a Type 2 and Type 3 Dual Carriageway. In terms of selecting the appropriate carriageway a Type 2 Dual Carriageway would be considered as preferable for an off line route while, in accordance with NRA TD10, Type 3 Dual Carriageways are now only intended for



online upgrades of existing roads with limited road frontage and appropriate existing road geometry. The proposed N5 Westport to Turlough Road Project has been developed as a Type 2 Dual Carriageway based on the above recommendations of NRA TD9. The validity of this carriageway type selection has been confirmed by consideration of a Type 1 Standard Single Carriageway alternative through an incremental analysis.

2.6 ‘Do-Minimum’ Consideration The ‘Do-Minimum’ consideration investigated the existing road infrastructure and its ability to meet future demands for traffic and safety without any upgrade works, other than routine maintenance. Section 2.4 of this report details the existing road conditions while this section of the report summarises the findings in relation to the ‘Do-Minimum’ scenario.

2.6.1 N5 Westport In terms of a ‘Do-Minimum’ scenario if no upgrades were considered in the vicinity of Westport the growing traffic volumes within the town itself would increase delays and congestion within the town resulting in increases in already poor journey times in and through the town. Due to the low speeds experienced within the town the number of accidents and fatal accidents occurring here are low. With the N5 and N59 connecting in the centre of Westport traffic travelling between Newport and points further north along the N59 and the N5 towards Castlebar will continue through the town if no new route is provided. This traffic includes commuters travelling to the Allergen and IDA sites on the east side of Westport, commuters heading to and from Castlebar, long distance traffic heading to and from the east of the country and tourist traffic accessing the west. The continued mingling of local, commuter and long distance traffic will continue in the Do-Minimum scenario. A system of one way streets, signalised junctions and other traffic calming measures have already been installed within the town to relieve congestion. Further similar measures are not likely to improve the current conditions, and will not be sufficient to facilitate future growth.

2.6.2 N5 Westport to Castlebar The existing carriageway cross section is below the current minimum standard for a National Road i.e. a Type 2 Single Carriageway (without hard shoulders) at certain locations, and largely below the standards required for a Type 1 Single Carriageway due to the lack of hard shoulders over 80% of the length. The geometry of the road with a number of inappropriate curves for the posted speed also leads to dubious overtaking conditions and a reduction in safety. Even with improvements in road surfacing and maintenance of existing hedges, improvements for traffic in terms of journey time and level of service are not likely due to predicted increases in traffic volumes. Current traffic levels along this length of road are approximately 11,400 AADT which exceeds the capacity of a Type 2 Single Carriageway road by 32% and are approaching the design capacity of a Type 1 Single Carriageway road. Traffic levels of 12,000 AADT and 13,700 AADT in 2018 (Opening Year) and 2033 (Design Year) respectively are predicted to exceed the design capacity of a Type 2 Single Carriageway road by 40% by 2018 and by 60% by 2033, even exceeding the greater capacity of a Type 1 Single Carriageway 3% in 2018 and by 18% in 2033.



With traffic volumes exceeding the capacity of the road there will be a corresponding increase in delays resulting in a reduction in level of service. The accident rate along this section over the period 1996 to 2011 is as follows: • Fatal - 7 • Serious injury - 18 • Minor accident - 65 These accident figures are likely to increase in number and frequency as the traffic volumes increase. Without upgrading, this section of the N5 will have insufficient capacity for traffic which will result in increased delays to journey times, decreases in level of service and further decreases in safety.

2.6.3 N5 Castlebar This section of the existing N5 lies mainly within Castlebar and is an urban road with frequent junctions to Local, Regional and National Roads, businesses, access roads and houses. Major roundabout junctions are formed with the R310 and R373 Regional Routes and N60 National Secondary Route. The N60 also connects to the N84 National Secondary Route just south of the N5 / N60 junction. Vehicles on the N60 and N84 wishing to access the N5 are required to enter the town of Castlebar leading to junction capacity problems and delays at peak traffic flow periods. These delays on the N5 lead to further delays and congestion within Castlebar town itself as vehicles on the local and access roads cannot join the N5 leading to congestion within the town centre.

The road cross section is equivalent to a Type 2 Single Carriageway, i.e. without hard shoulders, with local widening to provide additional lanes on the approaches to the roundabouts and nearside passing opportunities at other local road junctions. Base Year 2013 two-way traffic volumes of 14,800 on the western approach to the town and 14,400 AADT between the N60 and R373 junctions already exceeds the design capacity for a Type 2 Single Carriageway by 72% and 67% respectively. This has the effect of decreasing the Level of Service (LOS) with significant congestion occurring at peak times. This congestion will increase further as traffic volumes increase, resulting in traffic growth on both Humbert Way and Lawn Road becoming capacity constrained. The accident rate along this section over the period 1996 to 2011 is as follows: • Fatal - 1 • Serious injury - 4 • Minor accident - 31 The existing available road space has already been configured to provide maximum capacity, with hard shoulders converted to left turning lanes on the approach to junctions. Without a more significant upgrade of this section of the N5 including an upgrade of the major junctions at the N60, R310 and R373, this section of the existing route will continue to have insufficient capacity for current and future traffic.

2.6.4 N5 Castlebar – Turlough This section of the existing N5 from the R373 Roundabout to Turlough is a section of road that was constructed on what was then a new greenfield off-line alignment, opened to traffic in 1990. The road cross section and geometry are all sufficient in



terms of standards for a Type 1 Single Carriageway. However the junction configurations do not comply with current design standards for a National Road.

The 2013 Base Year AADT of 11,000 are currently on the limit of the design capacity for the Type 1 Single Carriageway currently provided, resulting in limited overtaking opportunities. With a predicted traffic volume of 13,100 AADT in the Design Year of 2033 for the Do Minimum scenario, this volume will exceed this roads design capacity by 13%, leading to increased congestion and a reduced Level of Service. In terms of safety the existing road has two at-grade cross road junctions at the L-5874 (Clogher Road) and at the L-5779 (Gortnafolla Road) that are not permitted under the current design standard for at-grade junctions NRA TD 41-42, Clause 2.34 where crossroads are considered unsuitable for all rural road junction types ALONG National Roads. Similarly the junctions formed at the L-5785 North and South (Windsor Road), although staggered are staggered such that crossing traffic makes a left-right manoeuvre rather than the preferred safer right-left manoeuvre, while no ghost islands are provided for right turning traffic. In accordance with NRA TD 41-42, Clause 2.35, all of these junctions would require Departures from Standard. Of particular concern is the L-5779 (Gortnafolla Road) at-grade junction to the south of the existing N5 where significant turning movements related to slow moving HGV’s turning into an existing quarry and waste management facility. The accident rate along this section over the period 1996 to 2011 is as follows: • Fatal - 3 • Serious injury - 10 • Minor accident - 21 As traffic levels increase and reducing levels of service lead to greater driver frustration and potentially more dangerous overtaking manoeuvres, safety will inevitably be further compromised. This section of the N5 forms part of the vital Linked Hub of Castlebar and Ballina within the National Spatial Strategy. The current single carriageway does not have sufficient capacity for current or future traffic needs.

2.7 ‘Do-Minimum’ Summary Consideration of the existing road conditions and expected traffic growth reveal that the existing N5 has a poor safety record, provides a poor level of service and will experience increasing traffic congestion with all of these problems exacerbated by the significant sections of poor alignment, reduced cross section, frequent junctions with local roads and numerous properties with road frontage. It is therefore not recommended that further consideration be given to a ‘Do-Minimum’ scenario. In summary, it is concluded that a “Do-Minimum” scenario would result in unacceptable further deterioration to the level of service and poor safety record of this section of the N5.

2.8 ‘Traffic Management’ Alternative The ‘Do-Minimum’ scenario identified that the existing N5 presented generally poor road geometry and / or lack of capacity for current and future traffic with a poor safety record. As an alternative to the ‘Do-Minimum’ scenario, the ‘Traffic Management’ alternative investigated the potential to upgrade rather than replace the existing



infrastructure to meet the predicted demands for the next 30 years. While speed reducing traffic management measures can be used to address safety issues, these would further exacerbate the current congestion problems, leading to a further reduction in the level of service. In order to meet the predicted demand a major on-line upgrade of the existing N5 route would be required, sufficient to make it capable of delivering the required levels of service and safety in accordance with the current design standards. The analysis of improving each section of the N5 was as follows:

2.8.1 N5 Westport Due to the confined and urban nature of the existing roads within Westport, further on-line upgrading of the N5 within Westport and the N59 heading north from the centre of Westport to Deerpark East is not considered feasible or desirable. Plate 2.15 shows the street cross section and traffic congestion on the N5 within the centre of Westport. Due to the shared use of the existing infrastructure by both local town traffic and through traffic on the N5 and N59 it is not feasible to restrict any upgrade to the National Roads alone. Rather, to ensure free flow conditions on the through route the whole road network within the town would have to be re-configured to prevent local traffic from disrupting flows on the national routes. Any such scheme would involve major works, particularly at the junctions, requiring acquisition of houses and businesses on a massive scale. This would completely change the character of the town and would impact upon a number of protected and listed buildings. Due to the predicted increases in traffic within the town and the limited options for improvement, an on-line Traffic Management alternative is not considered viable in terms of delivering the required levels of service.

Plate 2.15 Streets and Traffic Congestion N5 in Westport

2.8.2 N5 Westport to Castlebar As part of the route selection for a previous N5 Westport to Castlebar scheme undertaken in the year 2000, the feasibility of an on-line upgrade of the existing N5 was considered and rejected. A re-examination of this route selection along with an



examination of the existing road was undertaken to determine whether an on-line upgrade would be feasible. Traffic and level of service To meet the requirements of Table 6/1 of NRA TD 9 with the predicted Design Year 2033 traffic flows of 13,700 AADT, a Type 3 Dual Carriageway could be considered. This carriageway type provides two lanes in one direction and one in the other, alternating every couple of kilometres and facilitates the retention of existing at-grade junctions. However as a Type 3 Dual Carriageway would nearly be at capacity for this road type in the Design Year this solution would have a limited life span. As an alternative a Type 2 Dual Carriageway would need to be considered as the preferred road type with a capacity of up to 20,000 AADT. If a Type 1 Single Carriageway was considered a reduced level of service would need to be accepted, with reduced average speeds and continued issues related to poor road safety and unpredictable journey times as is experienced presently. Road Type Due to the high level of road frontage as described in section 2.4.2 above, an on-line upgrade to Type 1 Single Carriageway, removing direct access, would create significant severance and impacts on properties. The additional land required for either a Type 2 or Type 3 Dual Carriageway would further exacerbate this problem. Geometry Of the existing horizontal curves along this section of the existing N5, 19 existing tight curves would need to be removed to meet current design standards for either a single or dual carriageway. In addition, for a single carriageway another curve would need to be removed to eliminate a dubious overtaking situation. Removal of these tight curves would require significant realignment of the route requiring the acquisition of at least 19 properties. Vertically the road has an undulating alignment which would require additional earthworks and roadworks to improve the vertical alignment, resulting in further significant local impacts and land requirements Junctions and Access The numerous existing Local Road junctions and accesses detailed in Section 2.4.2 above would all need to be upgraded to meet the geometric and visibility requirements of NRA TD 41-42. Due to the high number of individual house and field accesses onto the existing carriageway and the potential safety risks associated with multiple accesses within close proximity to one another, sections of parallel roads would be required to minimise the number of accesses onto the main carriageway. This would require significant additional land acquisition and property acquisitions. If an on-line Type 3 or Type 2 Dual Carriageway was considered even further impacts on properties would result along with additional requirements for frequent roundabouts and /or parallel access roads and bridge structures to cater for the field accesses and houses that would no longer be able to cross the segregated road carriageway. Land and Property Impact To provide the required road and junction geometry for a Type 1 Standard Single Carriageway for an on-line improvement a minimum of 35 properties including houses and businesses would need to be acquired. It is estimated that this would



increase to a minimum of 73 properties requiring acquisition if a Type 2 Dual Carriageway was provided along this length, with a Type 3 Dual Carriageway offering the potential to reduce this to somewhere between 73 and the 35 required for a single carriageway . The minimum width of land required for each of the carriageways is 18.3 metres for a Type 1 Standard Single Carriageway, 18 metres for a Type 3 Dual Carriageway and 21.5 metres Type 2 Dual Carriageway. These figures do not take into account additional lands required for parallel access roads, drainage, earthworks, construction space or maintenance requirements and other lands required for visibility and sight line requirements. As the existing average road reserve is approximately 15 metres from fence to fence, additional lands would be required along the majority of this length to accommodate a new road cross section. The land take requirement would be greater for both the single and dual carriageways for earthworks required to improve the vertical and horizontal alignment of the road to meet the stopping sight distance requirements for the appropriate design speed. Wherever parallel access roads would be required to concentrate access and minimise the number of accesses onto the main carriageway additional lands averaging 8 metres would be required. This would require further land acquisitions and property acquisitions. Viability of Upgrade Alternatives An on-line upgrade to Type 1 Standard Single Carriageway would not deliver the required level of service and would continue to suffer from the extremely high frequency of junctions and accesses on the existing road unless parallel collector roads were added. An on-line Type 3 Dual Carriageway has the potential to meet the level of service requirements in the short term, but would have no reserve capacity for traffic growth beyond the 2033 design year. It would require extensive parallel collector roads and frequent U-turn facilities to address the extensive house frontage access onto a segregated carriageway. A Type 2 Dual Carriageway could provide the required level of service with long term reserve capacity, but would have the same requirements for parallel collector roads if it were to be constructed on-line and in this case frequent roundabouts or compact grade separated junctions to facilitate U-turns. The constraints and impacts along this section of the N5, addressed here and in Section 2.4.2 of this report, in particular the estimated number of property acquisitions, disturbance and high level of existing access and junctions make all of these on-line upgrade proposals impractical and prohibitively expensive. A new off-line route is considered the appropriate proposal for improving this section of the N5 both in terms of minimising impacts and delivering value for money.

2.8.3 N5 Castlebar Traffic and level of service With predicted Design Year 2033 flows varying between 11,600 and 16,700 AADT along the various sections of the N5 approaching and through Castlebar town, a Type 2 Dual Carriageway would need to be considered as the preferred road type, having a capacity of 20,000 AADT. A Type 3 Dual Carriageway could be considered for the western approach to Castlebar between Derrylea and the R310 where the flows are lower. However the junction frequency and urban nature of this section of road is such that it would still be necessary to retain the existing speed restrictions, even if the congestion issues could be addressed.



Road Type Due to the close proximity of roundabouts it would in theory be possible to restrict the numerous existing junctions and access described in section 2.4.3 above to left-in, left-out manoeuvres onto a Type 2 Dual Carriageway. However the high level of road frontage, including the number of accesses and houses fronting on to the road would require the introduction of frequent pedestrian crossing points, which in turn would require a raised central median. Geometry The current road geometry would be sufficient for an on-line upgrade for the current imposed speed limits of between 50 and 60 kph. Consideration of an increased speed limit within this urban environment, to improve journey times, is not considered possible on road safety grounds and in terms of environmental impacts due to increased noise levels. Junctions and Access As a means of improving the traffic flows within the town the current roundabout junctions would need to be upgraded or improved. This could be though increasing the size of the roundabouts or providing grade separation. Compact grade separated junctions would require the existing N5 to be either elevated or depressed by approximately 7.5m above or below the existing road levels and the construction of new connector roads. An elevated road would cause major visual impact at these locations, such that the underpass option is most likely to be required. The approach ramps to a grade separated structure would extend over approximately 700m, such that the N60 and R373 junctions would effectively merge into a single underpass. The resulting grade separation on the approaches would make the provision of left-in, left-out junctions at the local and access road junctions impossible, requiring at-grade parallel collector roads to be provided. The land required to grade separate the existing N5 and construct the junction connector and parallel collector roads would result in the acquisition of a large number of dwellings and would have a major impact on the adjacent businesses and public facilities. Due to the space constraints and impacts on adjacent properties any grade separation would have to be achieved through the use of earth retaining structures, adding major cost to any such arrangement. The alternative option to construct larger roundabouts would be more achievable and cost effective, but would still have major impacts on surrounding properties, both businesses and houses. Existing Local Road junctions and accesses would all need to be upgraded to meet the geometric and visibility requirements of NRA TD 41-42. Parallel collector roads would still be required adjacent to the roundabouts to achieve a safe separation between the roundabout and the nearest local road junction. This would require significant additional land acquisition and property acquisitions. Land and Property Impact For an on-line Type 2 Dual Carriageway the minimum land requirement is 21.5 metres. If a Type 3 Dual Carriageway was considered to the west of the R310 roundabout this minimum requirement could be reduced to 18 metres over this length. These figures do not take into account additional lands required for parallel access roads, drainage, earthworks for construction space or maintenance requirements and other lands required for visibility and sight line requirements. As the existing road reserve generally varies between 12 and 18 metres with a slightly wider reserve of approximately 25 metres between the R310 and N60 Junctions,



additional lands would be required along the majority of this length to accommodate a new road cross section. Due to the high number of accesses and access roads, parallel access roads should ideally be provided to concentrate access and minimise the number of accesses on to the main carriageway. Additional lands averaging 8 metres on either side of the main carriageway would be required. This would require further land and property acquisitions. Viability of Upgrade Alternative On-line upgrading of this section of the N5 to overcome existing congestion and provide sufficient capacity to meet the predicted traffic levels for the design year would require widening to Type 2 Dual Carriageway Standard combined with major upgrades of the junctions, ideally through grade separation. Such a major upgrade within the constrained urban environment would have major impacts on the adjoining properties, incur major cost in terms of both construction and land and property acquisition, and greatly increase the severance associated with routing long distance traffic through the town. Even with the benefit of such a major upgrade this section of the National Primary route would remain subject to urban speed restrictions due to the need to maintain a safe environment for local traffic and non-motorised users, to minimise noise and vibration in the urban area and as a result of the frequent junctions and accesses. In seeking to serve high volumes of both local and through traffic such a road would be a poor compromise solution that would cause difficulties for both sets of users. Consideration of an on-line upgrade of this urban section of the N5 concludes that it would result in unacceptable impacts and deliver poor value for money. A new off-line route is considered to be the appropriate solution to provide a high speed bypass of the town and release capacity on the existing infrastructure to enable the town to develop as the Regional Hub as envisaged in the National Spatial Strategy.

2.8.4 N5 Castlebar to Turlough Traffic and level of service The traffic volume along this section of road, for the Base Year of 2013, is up to 11,200 AADT which approaches the design capacity of the current Type 1 Single Carriageway, which is already experiencing capacity and Level of Service problems. With predicated traffic flows of 13,100 AADT in the 2033 Design Year an on-line upgrade of this section to a Type 3 Dual Carriageway standard would again be approaching the design capacity for this road type which would barely meet the National Roads Authority’s target minimum Level of Service D, with its associated average speed of 80kph. As a result the preferred option would be for the provision of a Type 2 Dual Carriageway to meet the Design Year and future traffic demands along this section of road. Road Type An on-line upgrade to Type 2 Dual Carriageway standard would require minimal acquisition of additional land due to the combined width of the existing road carriageway, hardshoulders and verges. Junctions and Access There are no major constraints to the upgrading of the existing Local Road junctions to meet the requirements of an upgraded on-line dual carriageway. This could be achieved by a combination of bridging over, conversion to left-in, left-out and introduction of either roundabouts or compact grade separated junctions. There is a low level of road frontage other than field accesses which could be readily catered for by the provision of parallel access roads over some lengths of the upgraded road.



Land and Property Impact Due to the low level of road frontage other than field accesses the most significant increase in land requirements would be for the provision of parallel access roads. Additional lands would also be required for the provision of junctions and over-bridges where required. The affected lands are in agricultural use. In the few locations where the curtilage of residential or commercial property would be affected this would not be sufficient to demand full acquisition of the property. Viability of Upgrade Alternative Consideration of an on-line upgrade of this section of the N5 concludes upgrading to Type 2 Dual Carriageway standard offers a potentially feasible and cost effective solution to meeting the predicted traffic demands.

2.8.5 ‘Traffic Management’ Summary Consideration of the potential to upgrade the existing road infrastructure to meet the scheme objectives as described in Section 2.2 above concludes that these objectives could not be achieved in Westport, Castlebar or the section of N5 connecting these two towns. To achieve the Level of Service D required to deliver the Economic, Accessibility and Integration objectives requires the provision of a Type 2 Dual Carriageway between Westport and Turlough. The level of development along the existing route is such that the environmental impacts of upgrading to the required standards to meet this Level of Service and also meet the Safety objectives would be severe and unacceptable, especially in terms of the impacts on residential and business properties. Notwithstanding these impacts such a solution is considered to offer poor value for money due to the costs associated with the extensive property acquisitions and measures to mitigate the impacts, with a resulting compromise scheme. East of Castlebar the N5 passes through agricultural lands and is much less constrained, such that upgrading the existing infrastructure to the required Type 2 Dual Carriageway standard is a feasible option worthy of further consideration. It is therefore not recommended that further consideration be given to a ‘Traffic Management’ scenario in Westport, Castlebar or between the two towns, but that an on-line upgrade of the existing N5 east of Castlebar be considered within the overall route selection process.

2.9 “Do-Something” Scenario The conclusion reached following the assessment of the scheme objectives, the policy context, the nature of the existing infrastructure and consideration of “Do Minimum” and “Traffic Management” alternatives is that, in general, a new off-line route is the only feasible alternative that will adequately address the deficiencies of the existing road and cater for future traffic demands. The need is therefore identified to be a combination of bypasses for the towns of Westport and Castlebar connected by a new off-line carriageway. East of Castlebar an on-line upgrade is considered to be an appropriate solution to address the need for increased capacity and therefore this was included as one of the options in the route selection process.

chapter 2 need for the proposed road development...roughan & o’donovan -fabermaunsell alliance...

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