Preliminary Report on the Debe to Mon Desir SegmentJune 2012
Background
By letter dated 13th February 2012, the Highway Re-route Movement requested a meeting with the Prime Minister to request that the proposed Debe to Mon Desir segment of the highway be discontinued, and to propose an alternative route. The concerns of the Highway Re-route Movement regarding construction of the highway include:
• The Highway Route is Conceptually Flawed
• Dis-connectivity of Communities
• Permanent Flooding
• Demolition of Residences/Businesses/Places of Worship
• Destruction of Agricultural Lands
• Flawed Public Consultation
• Prohibitive Cost of the Highway
Subsequent to discussions held between the Prime Minister and several members of the Cabinet with the Highway Re-route Movement, the Ministry of Works and Infrastructure held a meeting on 18th April 2012 with both NIDCO and the Highway Re-route Movement to discuss the concerns of the group and determine the way forward. The Highway Re-route Movement reiterated its concerns of flooding and salt water intrusion, disruption of communities, cost of the segment, and that members of the Highway Re-route Movement directly affected by the highway do not wish to move.
The Highway Re-route Movement also stated that the lands proposed for relocation situated at Petit Morne were not acceptable to its members.
The purpose of this preliminary report is to address the primary concerns raised by the Highway Re-route Movement. It should be noted that NIDCO is about to commence additional studies which will address the concerns of the stakeholders and the wider community in greater detail.
The additional studies will involve reviewing the existing road network in the subject area, and determining a logical network that could accommodate the traffic entering and bypassing the Debe/Penal/Siparia to Mon Desirsegment, based on existing and future traffic volumes, and pertinent constraints.
Project Background
The Solomon Hochoy Highway Extension to Point Fortin has been conceptualized for many decades. The prefeasibility study (1998), the feasibility study and initial design (2005 – 2007) were completed by a foreign-local joint venture of ND LEA (Canada) and Trintoplan.
The LEA-Trintoplan studies showed that three distinctive traffic issues had to be addressed – 1. A more direct route between San Fernando and La Brea/Point Fortin was needed, 2. There were significant traffic delays on the segment of the SS Erin Road between Cross Crossing and Siparia, and 3. There were significant traffic delays on the 2-lane segments of the South Trunk Road and Southern Main Road between Cross Crossing and St. Mary’s Junction. Multiple alignments were considered by the designers prior to undertaking the detailed designs for the highway.
ALTERNATIVE ROUTES
As the detailed designs were completed more than five years ago(2005 – 2007) and for other pertinent reasons, a decision was made to tender the construction of the highway utilizing the Design-Build model of procurement. Construtora OAS Ltda, a Brazilian company was procured in 2011, with physical construction started in September 2011. Construction of the entire highway is scheduled to be completed in 2015.
Under the contract, OAS is fully responsible for executing the design of the entire highway on behalf of the Ministry of Works and Infrastructure and NIDCO. The Ministry of Works and Infrastructure and NIDCO must approve the designs.Accordingly, OAS has employed a highly respected international consultant, HALCROW to prepare designs that satisfy the requirements of the contract.
Further, design checks are carried out by an independent, highly regarded international consultant, ARUP. Technical oversight of the designs and construction is being done by AECOM (rated as the No. 1 consultant company in the world).
Project Characteristics
The SHHE comprises a new freeway with four 3.65 m wide lanes from Golconda to Pt. Fortin, and St. Mary’s Junction to Mon Desir. It includes widening the existing carriageway and construction of a new dual carriageway between Paria Suites and St. Mary’s Junction (4 lanes), and widening to arterial standards between Dumfries Road and Paria Suites (4 lanes).The total length of the proposed highway is approximately 50 km,upgradeable to 6 lanes as future traffic conditions require.
A nominal right of way of 100 metres was used to ensure that there is sufficient reserve for development over time and to facilitate the establishment of utility corridors on both sides of the highway. The initial LEA-Trintoplan design utilized the Association of American State Highway Officials (AASHTO) standards and met all statutory requirements.
Integral Benefits of the Highway
Background
By letter dated 13th February 2012, the Highway Re-route Movement requested a meeting with the Prime Minister to request that the proposed Debe to Mon Desir segment of the highway be discontinued, and to propose an alternative route. The concerns of the Highway Re-route Movement regarding construction of the highway include:
• The Highway Route is Conceptually Flawed
• Dis-connectivity of Communities
• Permanent Flooding
• Demolition of Residences/Businesses/Places of Worship
• Destruction of Agricultural Lands
• Flawed Public Consultation
• Prohibitive Cost of the Highway
Subsequent to discussions held between the Prime Minister and several members of the Cabinet with the Highway Re-route Movement, the Ministry of Works and Infrastructure held a meeting on 18th April 2012 with both NIDCO and the Highway Re-route Movement to discuss the concerns of the group and determine the way forward. The Highway Re-route Movement reiterated its concerns of flooding and salt water intrusion, disruption of communities, cost of the segment, and that members of the Highway Re-route Movement directly affected by the highway do not wish to move.
The Highway Re-route Movement also stated that the lands proposed for relocation situated at Petit Morne were not acceptable to its members.
The purpose of this preliminary report is to address the primary concerns raised by the Highway Re-route Movement. It should be noted that NIDCO is about to commence additional studies which will address the concerns of the stakeholders and the wider community in greater detail.
The additional studies will involve reviewing the existing road network in the subject area, and determining a logical network that could accommodate the traffic entering and bypassing the Debe/Penal/Siparia to Mon Desirsegment, based on existing and future traffic volumes, and pertinent constraints.
Project Background
The Solomon Hochoy Highway Extension to Point Fortin has been conceptualized for many decades. The prefeasibility study (1998), the feasibility study and initial design (2005 – 2007) were completed by a foreign-local joint venture of ND LEA (Canada) and Trintoplan.
The LEA-Trintoplan studies showed that three distinctive traffic issues had to be addressed – 1. A more direct route between San Fernando and La Brea/Point Fortin was needed, 2. There were significant traffic delays on the segment of the SS Erin Road between Cross Crossing and Siparia, and 3. There were significant traffic delays on the 2-lane segments of the South Trunk Road and Southern Main Road between Cross Crossing and St. Mary’s Junction. Multiple alignments were considered by the designers prior to undertaking the detailed designs for the highway.
ALTERNATIVE ROUTES
As the detailed designs were completed more than five years ago(2005 – 2007) and for other pertinent reasons, a decision was made to tender the construction of the highway utilizing the Design-Build model of procurement. Construtora OAS Ltda, a Brazilian company was procured in 2011, with physical construction started in September 2011. Construction of the entire highway is scheduled to be completed in 2015.
Under the contract, OAS is fully responsible for executing the design of the entire highway on behalf of the Ministry of Works and Infrastructure and NIDCO. The Ministry of Works and Infrastructure and NIDCO must approve the designs.Accordingly, OAS has employed a highly respected international consultant, HALCROW to prepare designs that satisfy the requirements of the contract.
Further, design checks are carried out by an independent, highly regarded international consultant, ARUP. Technical oversight of the designs and construction is being done by AECOM (rated as the No. 1 consultant company in the world).
Project Characteristics
The SHHE comprises a new freeway with four 3.65 m wide lanes from Golconda to Pt. Fortin, and St. Mary’s Junction to Mon Desir. It includes widening the existing carriageway and construction of a new dual carriageway between Paria Suites and St. Mary’s Junction (4 lanes), and widening to arterial standards between Dumfries Road and Paria Suites (4 lanes).The total length of the proposed highway is approximately 50 km,upgradeable to 6 lanes as future traffic conditions require.
A nominal right of way of 100 metres was used to ensure that there is sufficient reserve for development over time and to facilitate the establishment of utility corridors on both sides of the highway. The initial LEA-Trintoplan design utilized the Association of American State Highway Officials (AASHTO) standards and met all statutory requirements.
Integral Benefits of the Highway
- Construction of the proposed highway brings many benefits to the region and the country as a whole. Some of these benefits are summarized below:
- Reduction of traffic congestion afforded by an optimized design that allows for efficient flow of traffic and easy access to otherwise inaccessible areas for the transit of products, goods and services
- Reduction in road user and life-cycle costs in the form of savings in vehicle operating costsand travel time costs due to reduced travel distances created by more direct routes and increased travel speeds
- Provision of a safe, efficient, affordable, and aesthetically pleasing highway for all citizens
- Provision of improved access to Siparia, La Brea and Point Fortin to accommodate the anticipated economic growth (Note that Government has proposed the southwest region as an economic growth pole)
- Improvement of the local road network in the southwest region, increasing connectivity to the main population centres such as Debe, Penal, Siparia, Fyzabad, La Brea and Point Fortin
- Efficient movement of goods to/from ports within the Gulf of Paria
- The highway will promote a host of downstream industries poised to stimulate the transportation industry, service contractors, and small entrepreneurs who provide food and other ancillary products
- Construction of the highway will increase the demand for skilled and unskilled labour resources, thus potentially resulting in a decrease in unemployment levels and increase in income levels. It should be noted that the Contractor (OAS) must utilize a minimum of 40% local inputs which include skilled and unskilled labour as well as materials, equipment, and suppliers
- Additionally, there will be transfer of technology to the local construction industry
Traffic Impacts of Eliminating the Debe to Mon Desir Segment
The Highway Re-route Movement proposes that the new highway be stopped at Debe (and re-route traffic from Debe to Mosquito Creek), and that the Debe to Mon Desir segment be discontinued and replaced by upgrading existing local roads. This Highway Re-route Movement recommendation to simply upgrade local roads in the area raises serious concerns, including:
The Highway Re-route Movement proposes that the new highway be stopped at Debe (and re-route traffic from Debe to Mosquito Creek), and that the Debe to Mon Desir segment be discontinued and replaced by upgrading existing local roads. This Highway Re-route Movement recommendation to simply upgrade local roads in the area raises serious concerns, including:
- The residents of the region will not receive the benefits of a modern highway facility that they deserve (highlighted above)
- There will be no reduction in road user costs in the form of savings in vehicle operating costs (VOC), and travel time costs for the people
- The highway route has provisions for a utility corridor to accommodate WASA, T&TEC and other service providers to accommodate future expansion and maintenance of their infrastructure that will be required toservice the communities effectively wellinto the 21st century. This benefit will be lost as the local road network cannot facilitate the anticipated improvements
- Traffic congestion will continue in Debe, Penal and Siparia and worsen over time. A review of the local road network shows that even if the government improves the existing road network (which is on-going), connectivity to the main population centres such as Debe, Penal, Siparia, and Fyzabad will still have traffic congestion and safety problems today, which will worsen considerablywhen one accounts for the projected traffic volume expected in twenty (20) years. This also means that our people will have to commute for hours on a daily basis to get to and from work (Traffic congestion worsens since a road has a capacity to accommodate a certain volume of vehicles and the existing road through the local communities cannot be widened sufficiently to increase capacity, unless additional lands are acquired to do so)Traffic congestion will also be exacerbated with the imminent construction of the South UWICampus at Debe, the development of industrial parks through eTeck, and the newhospital to be built in Penal. These facilities will generate additional traffic with the attendant problems and inconveniences
A preliminary report analysing the Highway Re-route Movement proposal to upgrade existing roads is annexed to this report as Appendix I. The preliminary report concludes that the Highway Re-route Movement proposal is far from optimal as it superficially addresses the issue of severe traffic congestion in Debe/Penal/Siparia region.Social impacts of the Highway Re-route Movement’s alternative approach include disruption to the communities as a result of re-routing of traffic into residential areas.
Security and safety issues will increase with increased traffic through the local communities. Further, the additional capacity provided by upgrading the alternative routes is considered minimal at best.Consequently, stakeholders must carefully consider the net impact of this approach over the construction of the highway as currently envisaged.
The Allegation of Severing of Communities
The LEA-Trintoplan route selection was carefully analysed taking into account several factors including:
• Road lengths
• Environmentally sensitive areas
• Land use
• Terrain
• Soil conditions
• Accessibility and connectivity
• Opening new areas for development
• Minimizing acquisition of homes/businesses
Notwithstanding the careful analysis and selection of the final route, impact on communities cannot be avoided, only mitigated. This is an unfortunate reality for any highway to be built in Trinidad and Tobago due to the establishment and growth of our towns and villages in an unplanned manner, which has resulted in ribbon development along our roadways. Therefore, everywhere that a new highway will be built, communities will be disrupted. Effective and efficient transportation is a necessity for development of the country. New highways will have to built if we are to progress, and communities will be impacted upon.
The Government of Trinidad and Tobago has recognized that communities in the region will be impacted and has sought to minimise those impacts.
Accordingly, the Government agreed to relocatepersons residing in several communities affected by the highway between Debe, Penal and San Francique to a new development at Petit Morne. Residents from the affected communities would be given land at Petit Morne to build a new community inclusive of land for schools, early childhood development centres,religious activities (temple, mosque), sporting facilities and recreational green areas. Government has also agreed to set aside land for farmers who will be affected (2 acre plots).
Government, through NIDCO has established a Community Outreach Centre at Debe, where all affected/interested persons can obtain information on how their properties are impacted by the highway, and receive guidance on the compensation process. In general, the Government’s policy is to acquire lands for the highway by private treaty.
Affected persons will be entitled to market value for their property, reimbursement of costs incurred as a direct result of the acquisition (disturbance payment), and reimbursement of any reasonable costs incurred in determining the compensation. Disturbance payments may include but are not limited to:
Security and safety issues will increase with increased traffic through the local communities. Further, the additional capacity provided by upgrading the alternative routes is considered minimal at best.Consequently, stakeholders must carefully consider the net impact of this approach over the construction of the highway as currently envisaged.
The Allegation of Severing of Communities
The LEA-Trintoplan route selection was carefully analysed taking into account several factors including:
• Road lengths
• Environmentally sensitive areas
• Land use
• Terrain
• Soil conditions
• Accessibility and connectivity
• Opening new areas for development
• Minimizing acquisition of homes/businesses
Notwithstanding the careful analysis and selection of the final route, impact on communities cannot be avoided, only mitigated. This is an unfortunate reality for any highway to be built in Trinidad and Tobago due to the establishment and growth of our towns and villages in an unplanned manner, which has resulted in ribbon development along our roadways. Therefore, everywhere that a new highway will be built, communities will be disrupted. Effective and efficient transportation is a necessity for development of the country. New highways will have to built if we are to progress, and communities will be impacted upon.
The Government of Trinidad and Tobago has recognized that communities in the region will be impacted and has sought to minimise those impacts.
Accordingly, the Government agreed to relocatepersons residing in several communities affected by the highway between Debe, Penal and San Francique to a new development at Petit Morne. Residents from the affected communities would be given land at Petit Morne to build a new community inclusive of land for schools, early childhood development centres,religious activities (temple, mosque), sporting facilities and recreational green areas. Government has also agreed to set aside land for farmers who will be affected (2 acre plots).
Government, through NIDCO has established a Community Outreach Centre at Debe, where all affected/interested persons can obtain information on how their properties are impacted by the highway, and receive guidance on the compensation process. In general, the Government’s policy is to acquire lands for the highway by private treaty.
Affected persons will be entitled to market value for their property, reimbursement of costs incurred as a direct result of the acquisition (disturbance payment), and reimbursement of any reasonable costs incurred in determining the compensation. Disturbance payments may include but are not limited to:
- Cost of seeking and finding a new location in which to continue whatever the claimant was disturbed in doing
- The legal and other professional costs that would be incurred in securing the new location
- Any construction costs that might be necessary in adapting the alternate location to meet any special needs
- Any costs that might be incurred in adapting or replacing such items of soft furnishings that may need to be altered or replaced
- Any loss of business profits temporarily or permanently as a result of the dislocation
- In circumstances where lands are immediately required, consideration may be given to displaced persons occupying rented accommodation for a period up to one year while resettlement is pursued and rent reimbursements made.
A trained counsellor is also available at the Community Outreach Centre (at no cost to residents) to provide assistanceto residents who may require such help.
For those communities/persons that remain after the highway is constructed, the design requirements specified in the contract ensure that connector roads are provided to avoid severance and maintain connectivity.
The Allegation of Permanent Flooding
The region of concern falls within the South Oropuche River Basin:The basin is characterised by the Oropuche Lagoon, residential, industrial and commercial land use patterns. Flooding of the area occurs on a perennial basis, and flooding will continue to be part of life for the region (with or without the highway) if action is not taken to address the problem.Spillage of the Curamata River and Blackwater Channel results in complete inundation of the SS Erin Road and other major and minor arteries.Flooding is due to inadequate carrying capacities of the drains and increased surface runoff.
Floods will be more frequent and increase in severity as the area develops and the population grows over time. Mitigation of the problem will require detailed engineering studies followed by timely implementation of the solutions derived from those studies.
NIDCO has been mandated to undertake detailed engineering studies of the South Oropuche River Basin along with detailed designs of the proposed solutions. A consultant has been identified and negotiations are imminent with a view to awarding a contract by the end of July 2012 for the project. Some key objectives of the proposed study include mitigation of flooding, winning of potable water and storage of water for irrigation purposes. The matter of salt water intrusion will also be studied.
WASA and NIDCO are collaborating under this study where it is envisioned that threemillion gallons per day with direct abstraction and eighteenmillion gallons per day with storage provisions could be realized for the purpose of portable water supply. The South West will be served by this source, particularly the following areas:
Barrackpore, Penal, Debe, Fyzabad and Siparia.
The approach to flooding in the region therefore takes into account flooding due to the natural characteristics of the South Oropuche River Basin and possible flooding due to the construction of the highway.
Design of a new highway requires that the structure does not make the drainage of the area worse due to the structures’ installation. The Design-Build contract with OAS calls for the contractor’s design to ensure that the post-development peak flow is less than the pre-development peak flow.
A preliminary analysis of the contractor’s drainage design shows OAS is taking considerable flood alleviation measures to ensure that the upstream flow is controlled and mitigated. These measures include inter alia the use of multiple culverts, ditches, detention ponds, outfall controls, and erosion controls.
In conclusion, the Ministry of Works and Infrastructure and NIDCO are making every effort to mitigate the flooding concerns of the region by addressing the issue on two fronts, that is, by studying and implementing a plan for mitigating flooding in the entire South Oropuche River Basin, and by ensuring that increased runoff due to the highway structure is addressed using adequate flood alleviation measures in accordance with international design standards.
APPENDIX I
Report on the Discontinuation of the Debe to Mon Desir Segment of the Solomon Hochoy Highway Extension to Point Fortin
Introduction
The traffic volume at the Debe intersection of the SS Erin Road and the M2 Ring Road is of the order of 20,000 vehicles per day (referred to as Average Daily Traffic, or ADT) (Traffic Volumes and Operational Analysis report, Halcrow/OAS), March 2012).
This figure is expected to increase to approximately 30,000 vehicles per day by 2030 in both directions, or 15,000 vehicles in each direction. Based on standards for conversion of ADT to peak hour volumes (The Green Book, A Policy on Geometric Design of Highways and Streets, 2011), it is estimated that a peak hourly volume of 2,250 vehicles would be realized by year 2030.
This volume is equivalent to the capacity for two lanes in each direction for a city or town in the North American Society.
Based on a feasibility study conducted by Lea-Trintoplan in 2008, the capacity of a single-lane highway in the region, under free-flow conditions, would be in the region of 1,250 vehicles per hour. From the breakdown above, this figure is already exceeded and as such, two lanes in each direction would be required to adequately accommodate the traffic.
The capacity of an arterial lane, without ribbon development is of the order of 700 vehicles per hour, and with ribbon development, as is the case of the SS Erin Road, is of the order of 500 vehicles per hour according to the feasibility study. Therefore, without construction of a 4-lane highway in the region, creative means of distributing traffic to the side streets are required in order to provide a reasonable travel experience for the community.
The stakeholders are demanding that all the existing roads be upgraded in the Debe/Penal/Siparia region.
The option under consideration is as follows:
The SSHH will be terminated at a location just south of the proposed Debe interchange, at a point where it will link with the existing Bunsee Trace.
Traffic will not be allowed to make a left turn on to Bunsee Trace. Motorists with interests in the area east of this intersection will be required to exit at the Debe interchange, onto the SS Erin Road, then on to Bunsee Trace.
Bunsee Trace will then be improved as far as is reasonably possible to allow traffic heading further south toward Penal to proceed until the intersection with Suchit Trace. This intersection could be signalized in order to regulate the flow of traffic into the neighbouring community in addition to the mainline traffic heading into and beyond Penal.
The two prominent collector roads in the area of Siparia, heading toward Penal are the San Francique Road and the SS Erin Road.
These roads currently carry 6,571 and 5,176 vehicles per day [Traffic Volumes and Operational Analysis report, Halcrow/OAS), March 2012]. By 2030, based on growth trends, it is expected that, without the creation of additional capacity, the ADT volumes would increase to approximately 18,000 and 16,000 vehicles per day respectively. These figures would result in peak hourly volumes of 1,350 and 1200 vehicles per hour respectively. Given an optimistic capacity of 700 vehicles per hour during the peak period, the approach to be considered would be local widening of these existing roads where possible and redistribution of traffic in the region via appropriate signage.
Based on the present configuration of these roads and the unchecked encroachment, the maximum capacity at best would be 850 vehicles, which would not elevate the traffic congestion.
The major constraint in this methodology would be that new roads will have to be construction in and around the community to resolve the existing and projected traffic jams that would take place. This will mean that properties will also have to be acquired, in whole or part in order to achieve a reasonable level of service, so the traffic would flow, but still be subject to delays if any emergency or utility companies carrying out urgent works.
Analysis Using Existing Roads (Route map attached)
1. Complete the Debe interchange in accordance with the existing concept. It is critical that traffic heading further south toward Penal be segregated in order to reduce congestion at the intersection of the M2 Ring Road and SS Erin Road.
2. Continue the Solomon Hochoy Highway past the Debe interchange to a point on Bunsee Trace via a two-lane, first class road. This segment of the highway will be connected to Bunsee Trace via a two-lane roundabout or a traffic signal, depending on which solution best accommodates traffic flow through the intersection.
3. Upgrade the pavement structure of Bunsee Trace from the SS Erin Road in the north to Suchit Trace in the south to accommodate traffic that would be diverted from the SS Erin Road.
4. Develop Suchit Trace as the main connector from Bunsee Trace to the SS Erin Road which would then be the main access to Penal.
5. Upgrade Murray Trace from Siparia in the west to the SS Erin Road in the east. Segments of this trace appear to be of sufficient width to accommodate three lanes. This would be the main connection between the end of the highway in Siparia, and the SS Erin Road in Penal. Localized traffic can utilize the existing secondary road network to arrive at their points of interest.
Conclusion
It is the opinion of the analyst that the alternative proposal under consideration is far from optimal, as it superficially addresses the issue of severe traffic congestion in Debe/Penal/Siparia region. The preliminary traffic analysis suggests that without the new highway, the average travel time between Debe and Penal will increase from 30 minutes to 45 minutes, and the average travel time between Penal and Siparia will increase from 35 minutes to 50 minutes.
Social impacts of an alternative approach include disruption to the communities as a result of the rerouting of traffic into residential areas. Security and safety issues will be increased with increased traffic through the communities.
Given that the additional capacity provided by these alternative routes is minimal at best, then all stakeholders must carefully consider the net impact of this approach, over the construction of the highway as currently envisaged.
For those communities/persons that remain after the highway is constructed, the design requirements specified in the contract ensure that connector roads are provided to avoid severance and maintain connectivity.
The Allegation of Permanent Flooding
The region of concern falls within the South Oropuche River Basin:The basin is characterised by the Oropuche Lagoon, residential, industrial and commercial land use patterns. Flooding of the area occurs on a perennial basis, and flooding will continue to be part of life for the region (with or without the highway) if action is not taken to address the problem.Spillage of the Curamata River and Blackwater Channel results in complete inundation of the SS Erin Road and other major and minor arteries.Flooding is due to inadequate carrying capacities of the drains and increased surface runoff.
Floods will be more frequent and increase in severity as the area develops and the population grows over time. Mitigation of the problem will require detailed engineering studies followed by timely implementation of the solutions derived from those studies.
NIDCO has been mandated to undertake detailed engineering studies of the South Oropuche River Basin along with detailed designs of the proposed solutions. A consultant has been identified and negotiations are imminent with a view to awarding a contract by the end of July 2012 for the project. Some key objectives of the proposed study include mitigation of flooding, winning of potable water and storage of water for irrigation purposes. The matter of salt water intrusion will also be studied.
WASA and NIDCO are collaborating under this study where it is envisioned that threemillion gallons per day with direct abstraction and eighteenmillion gallons per day with storage provisions could be realized for the purpose of portable water supply. The South West will be served by this source, particularly the following areas:
Barrackpore, Penal, Debe, Fyzabad and Siparia.
The approach to flooding in the region therefore takes into account flooding due to the natural characteristics of the South Oropuche River Basin and possible flooding due to the construction of the highway.
Design of a new highway requires that the structure does not make the drainage of the area worse due to the structures’ installation. The Design-Build contract with OAS calls for the contractor’s design to ensure that the post-development peak flow is less than the pre-development peak flow.
A preliminary analysis of the contractor’s drainage design shows OAS is taking considerable flood alleviation measures to ensure that the upstream flow is controlled and mitigated. These measures include inter alia the use of multiple culverts, ditches, detention ponds, outfall controls, and erosion controls.
In conclusion, the Ministry of Works and Infrastructure and NIDCO are making every effort to mitigate the flooding concerns of the region by addressing the issue on two fronts, that is, by studying and implementing a plan for mitigating flooding in the entire South Oropuche River Basin, and by ensuring that increased runoff due to the highway structure is addressed using adequate flood alleviation measures in accordance with international design standards.
APPENDIX I
Report on the Discontinuation of the Debe to Mon Desir Segment of the Solomon Hochoy Highway Extension to Point Fortin
Introduction
The traffic volume at the Debe intersection of the SS Erin Road and the M2 Ring Road is of the order of 20,000 vehicles per day (referred to as Average Daily Traffic, or ADT) (Traffic Volumes and Operational Analysis report, Halcrow/OAS), March 2012).
This figure is expected to increase to approximately 30,000 vehicles per day by 2030 in both directions, or 15,000 vehicles in each direction. Based on standards for conversion of ADT to peak hour volumes (The Green Book, A Policy on Geometric Design of Highways and Streets, 2011), it is estimated that a peak hourly volume of 2,250 vehicles would be realized by year 2030.
This volume is equivalent to the capacity for two lanes in each direction for a city or town in the North American Society.
Based on a feasibility study conducted by Lea-Trintoplan in 2008, the capacity of a single-lane highway in the region, under free-flow conditions, would be in the region of 1,250 vehicles per hour. From the breakdown above, this figure is already exceeded and as such, two lanes in each direction would be required to adequately accommodate the traffic.
The capacity of an arterial lane, without ribbon development is of the order of 700 vehicles per hour, and with ribbon development, as is the case of the SS Erin Road, is of the order of 500 vehicles per hour according to the feasibility study. Therefore, without construction of a 4-lane highway in the region, creative means of distributing traffic to the side streets are required in order to provide a reasonable travel experience for the community.
The stakeholders are demanding that all the existing roads be upgraded in the Debe/Penal/Siparia region.
The option under consideration is as follows:
The SSHH will be terminated at a location just south of the proposed Debe interchange, at a point where it will link with the existing Bunsee Trace.
Traffic will not be allowed to make a left turn on to Bunsee Trace. Motorists with interests in the area east of this intersection will be required to exit at the Debe interchange, onto the SS Erin Road, then on to Bunsee Trace.
Bunsee Trace will then be improved as far as is reasonably possible to allow traffic heading further south toward Penal to proceed until the intersection with Suchit Trace. This intersection could be signalized in order to regulate the flow of traffic into the neighbouring community in addition to the mainline traffic heading into and beyond Penal.
The two prominent collector roads in the area of Siparia, heading toward Penal are the San Francique Road and the SS Erin Road.
These roads currently carry 6,571 and 5,176 vehicles per day [Traffic Volumes and Operational Analysis report, Halcrow/OAS), March 2012]. By 2030, based on growth trends, it is expected that, without the creation of additional capacity, the ADT volumes would increase to approximately 18,000 and 16,000 vehicles per day respectively. These figures would result in peak hourly volumes of 1,350 and 1200 vehicles per hour respectively. Given an optimistic capacity of 700 vehicles per hour during the peak period, the approach to be considered would be local widening of these existing roads where possible and redistribution of traffic in the region via appropriate signage.
Based on the present configuration of these roads and the unchecked encroachment, the maximum capacity at best would be 850 vehicles, which would not elevate the traffic congestion.
The major constraint in this methodology would be that new roads will have to be construction in and around the community to resolve the existing and projected traffic jams that would take place. This will mean that properties will also have to be acquired, in whole or part in order to achieve a reasonable level of service, so the traffic would flow, but still be subject to delays if any emergency or utility companies carrying out urgent works.
Analysis Using Existing Roads (Route map attached)
1. Complete the Debe interchange in accordance with the existing concept. It is critical that traffic heading further south toward Penal be segregated in order to reduce congestion at the intersection of the M2 Ring Road and SS Erin Road.
2. Continue the Solomon Hochoy Highway past the Debe interchange to a point on Bunsee Trace via a two-lane, first class road. This segment of the highway will be connected to Bunsee Trace via a two-lane roundabout or a traffic signal, depending on which solution best accommodates traffic flow through the intersection.
3. Upgrade the pavement structure of Bunsee Trace from the SS Erin Road in the north to Suchit Trace in the south to accommodate traffic that would be diverted from the SS Erin Road.
4. Develop Suchit Trace as the main connector from Bunsee Trace to the SS Erin Road which would then be the main access to Penal.
5. Upgrade Murray Trace from Siparia in the west to the SS Erin Road in the east. Segments of this trace appear to be of sufficient width to accommodate three lanes. This would be the main connection between the end of the highway in Siparia, and the SS Erin Road in Penal. Localized traffic can utilize the existing secondary road network to arrive at their points of interest.
Conclusion
It is the opinion of the analyst that the alternative proposal under consideration is far from optimal, as it superficially addresses the issue of severe traffic congestion in Debe/Penal/Siparia region. The preliminary traffic analysis suggests that without the new highway, the average travel time between Debe and Penal will increase from 30 minutes to 45 minutes, and the average travel time between Penal and Siparia will increase from 35 minutes to 50 minutes.
Social impacts of an alternative approach include disruption to the communities as a result of the rerouting of traffic into residential areas. Security and safety issues will be increased with increased traffic through the communities.
Given that the additional capacity provided by these alternative routes is minimal at best, then all stakeholders must carefully consider the net impact of this approach, over the construction of the highway as currently envisaged.
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