Chapter 16 Road Sector Development Plan 16.1 Road Network
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Nicaragua National Transportation Plan Final Report Chapter 16 Road Sector Development Plan 16.1 Road Network Improvement Plan 16.1.1 Introduction As mentioned in Chapter 13.5, the main policies of the transport sector in the National Transport Plan is to develop a transport network system to support economic growth, assist social activities so as to decrease regional disparities, and to develop infrastructure resilient to the impact of climate change. This chapter discusses the various measures to realize the policies established. 16.1.2 Planning Methodology Figure 16.1.1 illustrates the planning process of the road network development plan. The development projects or the candidate projects that will contribute in improving the existing road network will be selected by integrating the projects that are being implemented or are on the course of planning by MTI with the proposed improvement works to improve the present road network. Present Road Network On-going and Planned Projects Planning Concept Proposed Improvement Works Proposed Road Network Development Projects (Candidate Projects) Figure 16.1.1 Planning Process of Road Network Development Plan Source: JICA Study Team 16.1.3 Present Road Network Although, the total road network in Nicaragua totals to 23,647km, only the basic road network under the jurisdiction of MTI, which totals to approximately 8,517 km (trunk road and collector road) will be targeted for road network development plan. 16.1.4 Integration of On-going and Planned Projects On-going projects and planned projects for fiscal year 2014-2016 were identified and those that needed to be included in the NTP were selected. Currently, there are some projects that are on-going. There are some more that has been planned for implementation in MTI’s investment plan for 2014-2016. The lists of these projects are provided in chapter 8. Where the on-going projects are mostly related to renovation of existing roads, many of the planned projects are yet to find a financial resource for commencement of construction work. Therefore, these projects, with an 16-1 Nicaragua National Transportation Plan Final Report exception to the three projects mentioned below, have been included in the improvement works in the NTP. The three projects hereunder are on-going and are expected to be completed shortly. The first two projects are related to new construction. However, these roads are planned in the NTP to be upgraded to a higher class from its present class as mentioned in the succeeding section. The third project is rehabilitation of NIC-21A from El Pajero to Muy Muy. i) NIC-71 (Nueva Guinea to Bluefields) ii) Nueva Esperanza to El Tortuguero iii) NIC-21A (El Paraíso to Muy Muy) 16.1.5 Planning Concept Figure 16.1.2 illustrates the basic concept of the improvement works for realizing the road sector D development strategies A mentioned in the previous D chapter. Concept ‘A’ targets enhancing intermodal connectivity and multimodal transport systems by strengthening the principal corridors that would minimize the travel time between the Atlantic side and Pacific Side B international class ports. A Concept ‘B’ targets C improvement of the existing roads in high potential productive area to reduce the C vehicle operation cost and enhance the industrial Figure 16.1.2 Planning Concept activities. Source: JICA Study Team Concept ‘C’ aims to provide reasonable access to strengthen communications and regional activities of communities in the eastern side of the country that currently have no accessible roads. Concept ’D’ aims to establish road network resilient to natural disasters to minimize adverse effect on life of people and economy due to damages to infrastructure induced by natural disasters. The basic directions followed in planning the improvement works are as follows: i) Utilization of existing roads to the possible extent ii) Enhancement of Functional and hierarchical road network iii) Securing safe and stable road and structures iv) Maintaining service level v) Guide future land use 16.1.5.1 Functions and Characteristics of Roads and Design Standard Nicaragua applies SIECA Standards, which is complemented by the American standards recommended by AASHTO. Although the SIECA standard is based on AASHTO, certain criteria are seen to vary from by AASHTO recommendations, mainly because of modifications undertaken to adapt to the regional conditions. One such example is the standards for widths (lanes, shoulders, sidewalks). It not only differs from the recommended values of AASHTO, but also do not correspond to the functional classification. 16-2 Nicaragua National Transportation Plan Final Report Therefore, the study recommends application of AASHTO’s standard for planning the roads. The proposed functions, characteristics and major design criteria are recommended as shown in Table 16.1.1. The cross sections to be applied for each class are shown in Figure 16.1.3 and Figure 16.1.4, which is followed by brief explanation of each cross section elements. Table 16.1.1 Proposed Functions, Characteristics and Design Standard ARTERIALS COLLECTORS Class Secondary Local Roads Item Main Trunk Secondary Trunk Main Collectors Collectors Function Important road Important road Important road Important road Important road network for Central network for network for network for network for American Region Nicaragua at a Nicaragua at a Nicaragua at a Nicaragua at a and connect National Level and regional level, regional level, municipality level departmental connect Connect with one or connect regions or and Lies under capitals and departmental more departmental municipalities to the MTI jurisdictions economical centers capitals, important capitals with national road but do not meet with populations economic centers as population over network, connect the requirements over 50,000 people. well as provide 10,000 people, regions or of upper category access to border connect urban areas municipalities with roads posts and connect not covered by more than 5,000 primary arterials arterials and connect population to the secondary arterials. national road network Correspondence Central American Primary National Secondary National Tertiary National Municipality to SIECA Road Road Road Road Road classification Mesoamerican Highway Traffic Flow AADT 1000 or more ⋜500<1000 approximately 500 50 or more 50 or less (vehicles per day) Design Traffic 17 – 18 by lane (ADT) (International 10 – 12 10 – 12 10 – 12 (Unit: Corridors) (9 in case of 2-lane) (9 in case of 2-lane) thousand) 10 – 12 for others Design Speed 100, 80, 60 80, 60, 50 60, 50, 40 50,40,30 40, 30, 20 (km/h) Target Speed 60 40 30 20 20 (km/h) Right of Way 40m 40m 40m 20m 20m (m) Level of B B C,D C,D D Service Lane Width (m) 3.6 3.6 3.3 3.0 3.0 Median Width 6.0 -10.0 2.0 – 9.0 3.0 – 4.8 3.0 – 4.8 None (m) Urban only Shoulder (m) 0.6 - 2.5 0.6 - 1.8 0.6 – 1.5 0.3 - 1.2 0.5 Sidewalk (m) 2.0 – 4.5 2.0 – 4.5 2.0 – 3.5 If required If required Urban only Note 1: Service Level B: Reasonably free flow, C:Stable flow D:Approaching unstable flow Note 2: Number of lane is decided based on future traffic demand forecast Source: Red Vial Nicaragua 2011, MTI and AASHTO 16-3 Nicaragua National Transportation Plan 16 - 4 Final Report Figure 16.1.3 Proposed Standard Cross Section for Main Trunk Road (Urban Area) Source: JICA Study Team Nicaragua National Transportation Plan Final Report Figure 16.1.4 Proposed Standard Cross Section for Each Functional Claffication Source: JICA Study Team 16-5 Nicaragua National Transportation Plan Final Report (1) Pavement Type Pavement type selection is a management decision process. The successful application of the pavement-type selection process requires a multidisciplinary approach and needs to take into account various factors such as construction cost (initial and life cycle cost), design life, traffic type, traffic volume, functional classification, ambient climate condition etc. Roads in Nicaragua have either asphalt, concrete, adoquín, or gravel pavement. The main trunk roads and most of the secondary trunk roads and collector roads in the western side of the country basically have asphalt pavement. Concrete pavement is observed in the eastern part of the country. The improvement works proposed in the NTP assumes application of asphalt pavement. In general, the study team recommends asphalt concrete on all roads, particularly the trunk roads. Generally asphalt pavement has advantages from the point of view of initial investment cost, repair, maintenance, splitting and cracking, and driving formability compared with hydraulic concrete. Application of concrete pavement or adoquín can be considered on collector roads, especially in the eastern side of the country where traffic volume is less and the materials are locally available and it does not require high level technology or heavy special equipment to construct. It also generates employment opportunities for the community. However, it should be noted that the pavement type and structure should be determined based on the actual requirements of the site. (2) Drainage facilities The major reason for deterioration of road condition is improper drainage system. Adequate drainage facilities are recommended to be provided in all roads in the urban area and along the following segments of a rural road. lowest section of a sag curve, where the longitudinal grade (profile) exceeds 3 percent, a cut section (rain from the road side in-flows to the road), creek or streams, and swampy area, rivers or watershed area, (3) Road Ancillary facilities To endorse safety and smooth operation of traffics, provision of road ancillary facilities is important and these facilities should comply with the standards of the country. Recommendation for provision on the roads proposed is discussed hereunder.