Transportation Planning Project - Assignment Example

Introduction When doing a real estate development project, the issues of easy access, proximity to transport infrastructure, and how traffic affects access to the project are important considerations. Vehicular traffic has a direct influence on real estate developments and traffic impacts surveys are essential to developers and public institutions to comprehend how transportation affects proposals for land development. The impact surveys are done to establish the impacts traffic has on new developments for instance office blocks, apartment developments, mixed use developments, and retail centers among others; on existing public transport systems and facilities. Traffic impact surveys are important to developers and authorities to assess how new developments affects existing transport infrastructure and traffic, make adjustments to existing plans, and helps obtain approvals for construction projects. This report contains the information, data, analyses, discussions, and conclusions for a traffic impact survey for the construction of a fourteen storey mixed use block at the intersection of Alameda and Colorado Boulevards as shown in figure 1 below. The facility will house offices in the lower floors and apartments on the remaining floors. The mixed-use facility will require parking space for office tenants as well as the residents. Its location at a major intersection necessitates a comprehensive traffic impact survey. The site at present is a low-rise building that houses a fitness centre but has an appreciable traffic volume flowing in both the main roads; Alameda and Colorado boulevards. The site is a three acre space measuring 135 000 square feet of land. Figure 1: Site map showing existing transport infrastructure Development: The new development is apartment building and offices. The plan is to do 14 floor building; the first (4 floor) can be companies’ offices and the rest of the building (10floor) residential, each floor can have 8 apartments. Parking is also important issue to think about when we do a project; we can use 15 % of the land area for parking. Traffic count and turning count: The next figure shows the number of cars that cross the intersection in different direction taken in Dec 2007 , over 24 hour period Problem statement When undertaking any construction project in an urban area especially next to existing transport infrastructure, it is imperative that the effect of the new development on traffic and existing public transport systems be done. the future traffic volumes and flows need to be carried out and preemptive measures put in place for eventualities after the development is complete Justification A traffic impact survey is therefore important in obtaining approvals for the development from local authorities, help make changes and adjustments in the original plan and cater for the vehicular traffic that will use the building. The building being mixed use is going to be accessed by both residents and office users; their access to the development must not interfere with the existing traffic flow. It will give the planners and local authorities a clear picture of how the development will affect existing transport infrastructure and traffic flow Method Preliminary information on the site was obtained from secondary sources and includes an aerial map of the area to show its location in relation to the existing transport infrastructure. The map is to scale to help with planning and projections The next step is the reviewing and surveying the traffic conditions existing in the particular location. Project the expected peak traffic to and from the proposed development and its influence the existing traffic flows. Recommend on the most practical and effective access points to and from the building bearing in mind the general traffic flows. Evaluate the traffic conditions at peak hours on the existing access routes, and their influence on vehicular access to the construction project. Literature review The public, surrounding community and the authorities have interests in knowing the effect of a new development on the existing transport facilities to recognize and respond to any additional demands placed on the existing transport system and traffic. This is in line with the general shared goal of smooth uninterrupted traffic flows even after the development is put up. A properly done and exhaustively done traffic impact surveys is important in providing a practical basis for making sound and effective decision making and allow for the making required adjustments in good time. Traffic impact surveys are done based on the standards set by the ITE (Institute of Transportation Engineers) as they offer a uniform traffic impact study standard so planning for access routes to the site, the layout of the parking and any other developments is consistent . A traffic impact study should incorporate the following An introduction Base conditions for traffic The generation of traffic from the site The distribution of traffic at the site Traffic projections that are outside the development site A review of the site’s plan A discussion of traffic conditions in the future A summary of the study, with recommendations The assigning of traffic Results Traffic movement and turning Existing traffic conditions The next figure shows the traffic conditions at the Alameda and Colorado boulevard intersections over a twenty-four hour period. Most traffic according to the data is ‘straight on’ meaning traffic on the Alameda Boulevard drives straight through while traffic on the Colorado Boulevard also drives straight ahead. Some turning traffic is quite substantial showing that the traffic along the two boulevards is a lot with an equally high number of turning traffic therefore access to the new development must consider these. There is heavy traffic moving in the opposite directions for both Colorado and Alameda Boulevards. Daily traffic counts (actual) show that 59680 vehicular traffic flow along the Colorado Boulevard in both directions; straight ahead without turning. This is very high traffic showing the boulevard is very busy. The Alameda Boulevard carries a total of 35 008 vehicular traffic in the same period, moving opposite directions without turning. Comparatively, the Alameda Boulevard is less busy than the Colorado Boulevard in terms of traffic that flows straight on. Traffic from Colorado Boulevard turning left into Alameda Avenue towards Burns Park totals 3876 vehicular traffic while those turning right into Alameda Avenue along cherry creek express lube are a total of 6732 vehicular traffic. Those turning left from Colorado Blvd. into Alameda Avenue along cherry creek express lube are 8674 vehicular traffic and those turning right into Alameda Avenue along Burns Park from Colorado Blvd. are 4436 vehicular traffic. Colorado Boulevard therefore experiences a total of 83398 vehicular traffic within just 24 hours. 2992 vehicles turn left into Colorado Boulevard along Burns Park from Alameda Avenue and 4353 vehicles turn right. From Alameda avenue 3567 vehicles, turn right from the east side of Alameda Avenue into Colorado Boulevard while 5326 vehicles turn left into Colorado Boulevard. This makes a total of 51246 vehicular traffic using Alameda Avenue in 24 hours. From the traffic flow, it would best suit the project managers to use Alameda avenue to access the site during construction as the traffic from that access route is much less. They should therefore access the site from the West on Alameda avenue and exit through Alameda avenue toward the east (along Burns park). This will ensure minimal interruption with the existing traffic Growth of traffic volumes During the construction period, traffic will be generated by the construction workers and this will be additional traffic to the existing traffic regimes on the Colorado and Alameda access routes. On completion of the construction, visitors to the offices, occupants of the office block and residents using the apartments will generate traffic. During construction, there is an expected increase in the number of traffic going in and out of the site because of the ongoing construction. On completion, the residents and tenants using the offices will generate additional traffic as well as visitors to the offices like clients. The increase in traffic will be mainly composed of heavy trucks bringing in construction equipment, workers cars, and other parties interested in the development. These are expected to have a major impact especially on the turning traffic on both the boulevards as trucks bringing in construction equipment such as cranes are usually huge and long and also wide. They generally move slowly due to the heavy equipment being carried and by their oversized nature. The turning angle for such trucks is huge is will therefore affect traffic in a major way. The location of the development site at a cross roads provides the advantage of two ways to approach and exit from the site. The Colorado and Alameda boulevards are busy roads as shown by the high traffic volume in a twenty-four hour period; showing a heavy demand for travel space. Construction of the development has potential of severely interrupting traffic flow in the two main access ways. A comprehensive traffic control and management plan in and around the construction zone is therefore essential. The traffic management plan should address ways in which traffic will be handled, how to reduce congestion, a system to inform motorists of the traffic interruptions in normal traffic flow systems, management of incidents and safety measures during the construction phase. The aim of traffic management and control in and around the development site is to ensure safe and expeditious movement of pedestrians and traffic around the site while ensuring construction equipment and workers remain safe (“Planning and Urban Design Standards” 523-526). A traffic control plan for a construction site can be either active or passive. The traffic from construction workers and other concerned parties will mainly consist of trucks (heavy trucks), light trucks, long and / or wide vehicles, vans and other automobiles. Trucks are classified based on vehicles with dual tires on at least one axle. Articulated tractor-trailers are classified as heavy trucks regardless of their weight. These in particular have the ability to cause massive disruptions to traffic flow especially when turning into or out of the construction site. The construction project is planned to take about sixty months to complete and the heavy trucks and traffic is expected to subside within the first half of the construction period. After that there will be traffic mainly form supervisors and suppliers of fixtures and fittings; with the main traffic expected to come from supervisors and will include vans and primary vehicular traffic. The traffic at this point is expected to have reduced fairly during the construction period. After the construction period, additional traffic will be generated by the residents and tenants and will have two main peak traffic periods. Mornings will have peak traffic coming in to the construction site while residents will be leaving the site for their daily activities in the morning. Evenings will also experience peak traffic coming from office tenants leaving the site and residents coming back home. In between, traffic is expected to be normal with minor increases in volume. Techniques for managing traffic This involves making the usual widths of lanes narrower in order to have more lanes or maintain the original number of lanes before the construction began. The shoulders of the road can be narrowed or completely removed to handle increased traffic. Implementing HOV or reversible only lanes reduces traffic and pedestrian flow during the construction period while closing ramps and restricting access to HOVs also reduce traffic demand. These steps lower or eliminate diverging and / or merging conflicts but their use must be done after assessing their corridor wide impacts (Saag 31-33). The ability to manage incidents should be given serious consideration and expanded when such actions as removing the road shoulders have been done. Speed management and control in and around the work site should also be managed as high traffic speeds pose a danger to the construction workers, other motorists, and the speeding cars themselves. Speed control at construction zones found in freeways can be either passive or active. Active control entails methods, which restrict traffic movement or enforce compliance with passive control methods. Flagging down vehicles, enforcing the law, installing message signs that are changeable depending on the situation, rumble strips, and reducing lane widths are some of the active methods available to control traffic speed (Saag 31-33). Passive control of speed entails using static road signs to control traffic. For instance, if previously the speed limit was 40 kph, a fixed static sign can be installed with a reduced speed limit of say 20 kph at the construction site. Passive methods are enough to control speed in situations where the hazards at the construction site are obvious and drivers have enough time to spot the hazards and adjust their speeds accordingly (Saag 31-33). Implementing flagging down of vehicles, having law enforcement officers, reducing lane widths, and installing message signs that are changeable generally are enough to control traffic speed during construction. Therefore, it is proposed that the project managers be allowed to increase lanes by shortening the existing lanes on the Alameda Avenue. Additional access lanes being built on the construction site to allow for easy entry and exit from the site be allowed. This should be by way of a paved access, off the main access roads and should take a little of the construction site area by about six meters. The paved access route should ideally be located along Alameda avenue as it seems to have less traffic and access and exit will be made easy since it falls on the right side of the Alameda avenue. This plan will ensure that there is minimal interference with the existing traffic routes during the construction period. This survey also proposes that the eastern section of Colorado Boulevard be marked with a fixed message sign that one is approaching a hazard area, with additional changing signs warning of hazards, as there may be overhead cranes that can cause hazards. This lane is generally not intended for much use, but should it be used by construction traffic, then the lanes are recommended to be reduced in width to increase the number of lanes. This is because traffic especially those coming from the south of Colorado Boulevard and turning right into Alameda Avenue have signs for slowing down and a warning of heavy trucks and other traffic turning. On Alameda Avenue, a fixed sign on both the east and western side of the road relative to the construction site should be installed warning of hazards of a road being constructed and heavy vehicles turning. Changing signs should also be installed with limits on the proposed speed limits depending on the construction phase. During construction of the paved access lanes, construction traffic will be forced to use the Colorado Boulevard and oncoming vehicles from Alameda Avenue should slow down; the additional lane created will be used to access the site. Vehicles should be flagged down to slow or stop to avoid exposing construction workers to accident hazards while keeping the vehicular traffic in particular those coming from the west along Alameda Avenue. During heavy construction phases, traffic police are proposed to be deployed to help direct and control vehicular traffic access and exit to the site and the general traffic. This will help ensure compliance with the fixed and changing road signs. Below is the proposed changes to the site and access and exit points for the project Burns Park Alameda Avenue Normal traffic flow Additional lane Additional paved Access lane into site Colorado Blvd. Projection of additional volumes of traffic due to construction The generation of trips is forecasted using the ITE (Institute of Transport Engineers) manual for trip generation and focuses on trip generation after completion of the project and start of occupancy. A trip generation refers to forecast of transportation, which calculates the trip numbers destined for, or originating from a specific traffic analysis precinct (“City of McAllen traffic impact assessment requirements”). The trip generation report helps determine whether a traffic impact assessment is necessary in the first place. The ITE manual for trip generation does not cover guidelines for trip generation during construction phases of projects. About 15 percent of the construction site will be reserved for parking and should be along Alameda Avenue covering the whole length of that side (300 feet) while along the Colorado Boulevard, about 69 feet will be set aside as parking space. The building will therefore be about 69 to 70 feet away from the Alameda Avenue and this serves as the parking area for both office users and the residents. According to the ITE manual for trip generation, the area will have high traffic due to its proximity to a recreational park; the ITE manual gives a trip generation of 0.16 trips per unit as the park is a city park (“ITE Trip generation rate (PM peak hour)”). Apartments have a trip generation value of 0.62 trips per unit for residential apartments while offices have a trip generation of 1.49 trips per unit (“ITE Trip generation rate (PM peak hour)”). These when tabulated gives the results shown below, with a standard deviation of 1. From the given figures, a traffic impact assessment is necessary for this project. These are the projected traffic volumes after completion of the construction project. The equation for the line of fit is y=x + 12 R2 = 1.0 During construction, the traffic numbers will rise, first with heavy trucks during the first thirty months of construction when heavy equipment and material is brought into the site. The next thirty months will see site traffic reducing to light trucks and vans as mostly supervisors and a few workers will now be at the site. Sixty months after the commencement of the project, tenants should start using the site generating additional traffic. The main access / entry point will be from the east of Alameda Avenue as there will be less turning and interruption of existing traffic. The addition of two additional paved access lanes will help in reducing interference with ongoing traffic. Exit is also on the same side; vehicles join the road from the east of Alameda Avenue, enabling a seamless integration with existing traffic. During construction, there will be traffic at the site; heavy equipment including diggers and excavators and big trucks/ heavy vehicles removing dug up soil from the site. Traffic at the site needs proper management to ensure safety of the workers and other personnel within the site. The front side of the site facing Alameda Avenue will be the main turning and parking site for construction vehicles. This is because it is the proposed access and exit side of the construction project. Changeable signs will be placed at different locations guiding drivers on where to enter the site and leave the site and warning signs to construction workers of the existing hazards. The construction crane will also be installed on this side of the construction at the far left corner. The work zones were determined by taking into consideration of the safety of workers, vehicle, and equipment operators, their ease of mobility, and providing positive guidance and information to workers on the hazards that are predicted within the construction site. The locations of the entry and exit points during and after completion of the construction project are done with the intention of as little as possible interference with the existing normal traffic flow. During construction, it is inevitable that normal vehicle traffic will be interfered with especially by the turning of heavy trucks; a site traffic manager in addition to the installed signs will give the drivers active guidance. The safety of pedestrians will be ensured through fixed signs placed at clearly visible points and the traffic warden will advice pedestrians to be at least ten feet from the entrance to the construction site. Since residents may frequently cross into the adjacent Burns park, it is recommended that a zebra crossing section be added across the Alameda avenue just in front of the exit / or entry point from the site to ensure pedestrian safety. Construction site work-zone A temporary work zone to control traffic will be established at the construction site to offer advanced warning to vehicles using the Alameda Avenue from the eastern section of impending hazards ahead. Flagging down vehicles and other fixed or changing signs will do this until traffic returns to normal path conditions after passing the construction site. The traffic work zone includes an area of approach, advance warning area, transition area, work area, a termination area, and a longitudinal buffer area. The advanced warning area will be at the intersection of Colorado and Alameda Boulevards intersection to alert road users of hazards ahead using changeable flashing lights and a fixed sign. It will also include a speed limit of 30 mph; the approach area is located just after the intersection to inform road users of changes in the lanes, reduction in speeds, restrictions for users and is meant to give road users sufficient time to adjust to the new traffic conditions. The transition area will be located just in front of the entry and exit points into the construction site and where traffic will be channeled to a different lane/ path to move traffic past the work/ hazardous site. This will be important during construction due to the projected entry, exit and sometimes turning of heavy trucks and equipment. The transition area will have devices for channeling traffic, including a traffic warden to physically give direction and traffic direction signs for instance flashing lights. A longitudinal buffer area, which is directly in front of the development site on Alameda Avenue, is to give protection to workers and equipment and drivers can use this to brake and come to a stop between the workspace/ entry and exit points and the end of the transition area. Conclusions and recommendations A traffic impact assessment is necessary for the construction project since the trip generation report shows there will be increased traffic flow during construction and upon completion of the project. Peak traffic after completion is projected to occur during both AM and PM periods as office users come into work in the AM period and residents leave for their daily activities during the same period. PM traffic will peak when residents are returning home and office users are leaving the work place to go home. These are also the traditional peak periods in the general traffic conditions. The Alameda Avenue is proposed for use as the exit and entry point into the construction site since the traffic on this road is lower compared to the Colorado Boulevard. The location of the site makes the use of Alameda Avenue easier as there will be little interference with mainstream traffic; vehicles will enter from the Alameda/ Colorado intersection and exit towards the east of the Alameda Avenue next to Burns Park. This will ensure no major interference with normal traffic flow. Active traffic control will be used especially form the access point on both Colorado Boulevard and Alameda Avenue with warning signs (fixed and changing), a traffic warden (in the initial construction phase). The lanes on the right side of Colorado Boulevard on the side of the development site will be reduced to create an additional lane for entry of vehicles into the development site. Along Alameda Avenue after the intersection, an additional paved lane for entry and exit from the development site will be built and will especially be useful after completion of the construction project. The trip generation shows a standard deviation of 1 and a regression curve/ line with the formula y=x + 12, so the trips can be projected by adding twelve to the number of occupants/ units within the site. The trips generated were calculated using the ITE manual for trip generation. The ITE manual for trip generation however does not have values for calculating trip generation to project additional traffic during construction, therefore ad hoc methods to estimate traffic generated at the construction site during construction are used. Recommendations Traffic lane sizes should be reduced during the construction phase (the first 30 months) on the right side Colorado Boulevard next to the development site. On turning right, an additional paved or tarmac lane be built on Alameda Avenue just in front of the construction site for entry and exit into the development site. Works cited Planning and Urban Design Standards Hoboken, NJ: John Wiley & Sons, 2006 523-526. EBook "Trip generation manual" ITE Trip generation rate (PM peak hour) Institute of transport engineers, 2008 Web 21 Apr 2012 Saag, J. Project Development Methodologies for Reconstruction of Urban Freeways and expressways Washington, DC: Transportation Research Board, 1999. 31-33 Print Read More