Case Study 2:
Michigan Department of Transportation Evaluation of the Temporary ITS for
the Reconstruction of I-496 in Lansing, Michigan
Project Background | ITS
Application |
Project Goals and Objectives |
Existing Agency Technical Capabilities
Additional Data, Technical Assistance, or Training Needs |
Analysis Method and Assumptions |
IDAS Analysis Results
Recommendations for the Project
|
Lessons Learned |
Project Cost and Schedule
Future Usage of Data and/or Technical Approaches Developed |
Contacts
Project Background
Lansing, Michigan, the State's Capital, is located approximately 90 miles northwest of Detroit. The Lansing region consists of three counties (Ingham, Clinton, and Eaton) with a combined population of 450,000. The largest municipalities are the city of Lansing (population 119,000); East Lansing (46,500); Meridian Township (39,000); and Okemos Township (23,000). Major employers in the region include the State of Michigan, Michigan State University, and General Motors Corporation.
The Lansing Region is well-served by limited access highways. I-96, I-69, and U.S. 127 combine to form a loop around the Lansing metropolitan area and provide good connections to major cities in the region. I-496 is an 8.5-mile freeway that runs in an east-west direction through the City of Lansing, parallel to the north and south portions of the loop. This freeway provides direct access to downtown Lansing, the State Capitol complex, and the largest General Motors facility in the region. Average annual daily traffic (AADT) ranges from 60,000 on the eastern portion of the freeway to 40,000 on the western end.
Overall travel in the region is estimated through the regional travel demand model to be 1.5 million person trips per day, 12.8 million daily vehicle miles of travel (VMT), and 290,000 daily vehicle hours of travel (VHT). Average trip length is approximately 8.5 miles, average trip time ranges from 11 to 12 minutes, and average speed from 41 mph in p.m. peak to 44 mph in the off-peak period.
Transit service in the region is provided by the Capital Area Transportation Authority (CATA). CATA recently merged with the Michigan State University bus system. CATA provides 24 fixed routes in the Lansing area in addition to demand responsive service in rural areas. Annual ridership is approximately 6.5 million, representing one to two percent of person trips in the region.
The Michigan Department of Transportation (MDOT) recently completed a major effort to repair and rebuild parts of the I-496 corridor through downtown Lansing. The reconstruction project, which began in April 2001, was completed ahead of schedule in September 2001. The total value of the investment was $42.4 million, and the section of I-496 that was reconstructed extended from the I-96 interchange on the west to Trowbridge Road in the City of East Lansing. A map of the construction project is shown in Figure 1.
Figure 1. I-496 Project Area
The key construction activities that were performed are as follows:
- Rehabilitation of 31 bridges and reconstruction of four bridges;
- Rehabilitation of six miles of freeway and reconstruction of 2.5 miles of freeway; and
- Addition of a third (merge/weave) lane in each direction between U.S. 127 and Pennsylvania Avenue.
The original construction plan called for a full closure of the eastern 2.5 miles of I-496 (shown in red on the map) for a period of five months. The second phase required closure of one lane in each direction for a period of approximately three months. The second phase was ultimately accelerated and combined with the first phase, allowing the project to be completed within six months.
ITS Application
The I-496 reconstruction project resulted in major changes in commuting patterns. Therefore, MDOT embarked on a concerted effort to help employers and residents of the Lansing region cope with this reduction in capacity of the region's transportation system. The efforts undertaken by MDOT to mitigate the impacts of the construction project included:
- A public education and outreach campaign, including traveler surveys and public information campaigns;
- The deployment of Intelligent Transportation Systems (ITS) technologies, referred to as the Temporary Traffic Management System (TTMS), to manage traffic and provide traveler information during the construction project; and
- Upgrades to signal system timing and operations on selected arterial corridors that serve as alternate routes for the construction project.
Specific ITS technologies and services deployed as part of the TTMS included:
- Closed circuit television cameras (CCTV) incident management system;
- Portable dynamic message sign (PDMS) equipment;
- Traffic queue detection devices;
- Video monitoring stations;
- Construction zone intrusion detection devices;
- Web-based traveler information dissemination;
- Dedicated telephone information hotline for construction project information;
- Construction Traffic Management Center (CTMC);
- Communications network equipment; and
- Construction Traffic Management Center (CTMC) software operating system.
In addition, major signal modifications were made on the M-43 corridor (Saginaw Highway/Oakland Avenue), which was designated as the major arterial relief route for I-496. Traffic data collected by MDOT indicated that each leg of the one-way pair and the western section of Saginaw highway carried about 40,000 vehicles per day during the reconstruction project, compared to normal ADT's of 22,000 to 30,000 vehicles per day. Signals were also upgraded on portions of Lake Lansing Rd., Grand River Avenue, and Coolidge Rd. Approximately 30 signals received significant upgrades. Signal timing was modified on Cedar and Pennsylvania Avenues and Martin Luther King Boulevard.
The TTMS delivered both static and real-time traveler information to the motorists through a variety of dissemination channels. The information collected through the CCTV cameras, queue detection devices, and microwave detectors was processed and disseminated through the following information sources:
- Portable Dynamic Message Signs (PDMS) - The PDMS served as the primary channel for enroute, real-time traveler information dissemination. The PDMS enabled the CTMC to post dynamic messages regarding work zone activity, traffic congestion, traffic incidents, alternate routes, speed restrictions, and other changing conditions or requirements. This information was concurrently transmitted to the Internet and the video monitoring stations for area-wide broadcast.
- World Wide Web Server - Information that was collected and disseminated through the PDMS was also transmitted over the Internet through MDOT's web site. In addition to this information, real-time video images from the CCTV cameras were also provided on the web site on a rotating basis.
- Video Monitoring Stations - Located in the transportation building in downtown Lansing and in four rest areas on freeways approaching the Lansing metropolitan area. The information that was displayed on the MDOT web site was available on these video monitoring stations as well.
- Telephone Hotline Information System - General information on the I-496 construction project and specific information on road and ramp closures were available through the MDOT telephone hotline (517-335-0496) dedicated to the I-496 reconstruction project. However, this system did not provide any real-time information on traffic congestion, incidents, or delays.
Project Goals and Objectives
The primary objectives of the temporary ITS system were:
- To provide, in conjunction with a variety of other activities, public information on the construction project;
- To monitor the impact of construction activity on traffic in the region, particularly on alternate routes; and
- To help mitigate the impact of traffic on alternative routes by providing real-time traffic information to the public.
MDOT, as part of its performance assessment program, hired Cambridge Systematics to conduct a benefit/cost (B/C) assessment of the TTMS used for the I-496 reconstruction project. This study was initiated during the early stages of the construction project. MDOT intends to use the lessons learned through the TTMS deployment and its B/C evaluation to assist in decision-making for the procurement and deployment of such systems in the future.
The purpose of the B/C evaluation was to identify the regional impacts of the TTMS on the roadway network and to document the benefits of the deployment using the ITS Deployment Analysis System (IDAS) model.
The primary goals and objectives of the analysis are outlined as follows:
- To identify the regional impacts of the TTMS on the roadway network in the Lansing region;
- To identify the benefits of the TTMS to MDOT, motorists, and the environment;
- To perform a benefit/cost analysis for the deployment of the TTMS;
- To develop recommendations for MDOT on the utility and relevance of ITS-based traffic management systems for improving mobility and safety in construction work zones; and
- To identify the benefits of the arterial signal system on the alternate routes.
Existing Agency Technical Capabilities
The evaluation of the I-496 TTMS was conducted under a contract with MDOT. Travel demand model sets used in the evaluation were obtained from both MDOT and the Tri-County Regional Planning Commission (TCRPC), which serves three counties in the Lansing region. The TCRPC model set used in the evaluation was an updated base year (2000) model. MDOT recently obtained IDAS; and the TCRPC, along with several other regional planning agencies in Michigan, will be obtaining IDAS in early 2002. It is anticipated that these agencies will be trained in the use of IDAS over the next year.
Additional Data, Technical Assistance, or Training Needs
In addition to the data obtained from the regional travel demand model to conduct the analyses, the study utilized data from various other sources in an attempt to better represent conditions in the Lansing region. A major study of future ITS deployments in southeastern Michigan was already in progress at the time of this evaluation. Work conducted for that project included the following:
- Consumer surveys in the Detroit and Lansing regions regarding ITS deployment and technologies;
- Development of a regional ITS architecture for the Lansing region; and
- Development of an ITS plan for the Lansing region.
The IDAS default impact values for the ITS components included in TTMS were adjusted (see Table 1) to reflect results from the following available background information:
- The types and extent of services provided by the TTMS (for instance, the hours of operation of the system);
- Consultation and input from MDOT personnel involved in ITS planning, and in the deployment and operation of the TTMS;
- The survey of public perceptions on ITS and usage of traffic information sources in both the Detroit and Lansing regions conducted as part of the MDOT ITS Pre-Deployment Study;1
- The anticipated response of the traveling public in the Lansing region to the ITS components and services provided by the TTMS; and
- Actual traffic data (traffic volumes, travel times, diversion patterns) collected by the TTMS and by MDOT personnel during the course of the TTMS operations.
Table 1. Comparison of Impact Values Used for the Lansing I-496 Evaluation
|
Impact Measure |
IDAS Default | Adjusted Value |
|---|---|---|
| Incident Management (Freeway Service Patrol and Reference Markers) | ||
| Reduction in incident duration | 55% | 20%1 |
| Reduction in fatalities | 10% | 6%1 |
| Reduction in emissions and fuel | 42% | 6%1 |
| Telephone and Web Information Services | ||
| Market penetration (percent using the service) | 1% | 1.4%1 |
| Time savings per traveler | 15% | 20%1 |
| Dynamic Message Signs | ||
| Percent time sign is on and disseminating information | 10% | 10% |
| Percent vehicles that save time | 20% | 20% |
| Time savings | 3 minutes | 3 minutes |
| Signal Coordination | ||
| Central Control Corridor Signal Coordination | 6 to 18% | 14%2 |
| Preset Timing Corridor Signal Coordination | 8 to 25% | 8%2 |
1Adjusted based on market research work and values adopted for MDOT ITS Pre-Deployment Study.
2Adjusted based on shift in volumes during construction period.
Following the analysis, the results of public surveys conducted by MDOT during and after the construction project were reviewed. The survey taken after completion of the project included questions about commuter response to TTMS elements. The results of these surveys generally confirmed the reasonableness of the adjustments made for the IDAS evaluation.
Impacts were "monetized" based on the default values supplied in IDAS. These values are documented in Table 2.
Table 2. Monetized Values of Effectiveness Measures
|
Effectiveness Measures |
Value | Unit |
|---|---|---|
| In-Vehicle Travel Time | ||
| Commercial Trucks | $20.80 | Hour |
| All Other Modes | $8.50 | Hour |
| Out-of-Vehicle Travel Time | ||
| Commercial Trucks | $20.80 | Hour |
| All Modes | $17.00 | Hour |
| Travel Time Reliability | ||
| Commercial Trucks | $62.50 | Hour |
| All Modes | $25.50 | Hour |
| Cost of Fuel | ||
| Auto | $1.21 | Fuel |
| Commercial Trucks and Buses | $1.15 | Fuel |
| Non-Fuel Operating Costs | ||
| Autos | $0.03 | Vehicle Mile |
| Commercial Trucks | $0.10 | Vehicle Mile |
Table 2. Monetized Values of Effectiveness Measures (continued)
|
Effectiveness Measures |
Value | Unit |
|---|---|---|
| Accident Costs | ||
| Fatality | ||
| All Modes - External Costs | $2,317,398.00 | Fatality |
| All Modes - Internal Costs | $408,952.00 | Fatality |
| Injury | ||
| All Modes - External Costs | $50,760.00 | Incident |
| All Modes - Internal Costs | $8,958.00 | Incident |
| Property Damage Only | ||
| All Modes - External Costs | $2,824.00 | Incident |
| All Modes - Internal Costs | $498.00 | Incident |
| Emissions | ||
| All Modes - Hydrocarbons | $1,774.00 | Ton |
| All Modes - Nitrous Oxides | $3,731.00 | Ton |
| All Modes - Carbon Monoxide | $3,889.00 | Ton |
| All Modes - Particulates | $11,066.00 | Ton |
| All Modes - Carbon Dioxide | $3.56 | Ton |
Analysis Method and Assumptions
The operating procedures and philosophies of the TTMS and the arterial signal system upgrades were used as a base to develop the parameters for the benefits analysis using IDAS. These are outlined below.
Time Periods of Analysis
Since the TTMS was operational from 5:00 a.m. to 7:00 p.m., the following three travel demand models for the Lansing metropolitan region were used for the IDAS benefits and impacts estimation:
- A.M. peak period travel model (7:00 a.m. to 9:00 p.m.);
- P.M. peak period travel demand model (3:00 p.m. to 6:00 p.m.); and
- Off-peak period travel demand model (all other time periods not covered by the peak period models).
Number of Analysis Periods
The scheduled first phase of construction was 150 days and the second phase 60 days.
Since the travel peaks are not expected to occur during weekends, the number of peak analysis periods for the entire duration of Phase 1 was 110 (assuming that there are 40 weekend days in five months), and for Phase 2 was 44 days.
The number of off-peak analysis periods was 150 for Phase 1 and 60 for Phase 2, respectively (assuming that the off-peak travel period applies to weekends as well).
Impacts Estimation and Benefit/Cost Analysis Process
The following steps were undertaken to conduct the benefit/cost analysis for this project:
- The travel demand networks and trip tables used for the analysis were provided by the Tri-County Regional Planning Commission (TCRPC), which is the metropolitan planning organization (MPO) for the three-county (Ingham, Eaton, and Clinton) Lansing metropolitan region. The Lansing travel demand models were recently updated in 2000 and were used for the MDOT ITS Pre-Deployment Study. The IDAS model was validated by comparing the vehicle miles traveled (VMT) values generated by IDAS with those from the original model.
- The travel demand models provided by TCRPC were then altered to reflect the freeway closure and lane closure of the two phases of the I-496 reconstruction project.
- The ITS components were then deployed on each of the three travel demand models, and IDAS was run to estimate the impacts and benefits of the system. The impacts of the deployments on the different travel performance measures during the three time periods were documented, and the total benefit calculated by adding the benefits across all three travel periods. The B/C ratio was then calculated by comparing the benefits of the deployments with the total cost.
- Three B/C ratios were calculated:
- TTMS (includes cost of the public information and advertising campaign);
- Arterial signal system upgrades; and
- MDOT's construction mitigation efforts.
- The cost of the TTMS was a one-time lump sum cost of $2,434,475, which was inclusive of both capital, operating, and maintenance costs for the TTMS.2 In addition to this, approximately $500,000 was expended for public information services prior to and during construction and an additional $500,000 to improve signal timing on parallel arterial corridors.
IDAS Analysis Results
The impacts on the regional roadway system of Phase 1 construction, which involved complete closure of the eastern 2.5 miles of I-496, were estimated through IDAS as follows:
- A change in VMT ranging from a 0.05 percent decrease during the off-peak period to increases of 0.13 percent during the a.m. peak period and 0.51 percent during the p.m. peak period.
- An increase in both vehicle hours traveled (VHT) and person hours traveled (PHT) of 1.02 percent during the off-peak period, 2.49 percent during the a.m. peak period, and 3.33 percent during the p.m. peak period.
- Decreases in average speed ranging from 1.12 percent during the off-peak period, 2.28 percent during the a.m. peak period, to 2.84 percent during the p.m. peak period.
- Decrease in the probability of the occurrence of fatality, injury, and property damage only (PDO) accidents due to reduced freeway travel. The values range from a 0.11 percent decrease during the p.m. peak period to a 2.05 percent decrease during the off-peak period.
- Increase in fuel consumption of 0.11 percent during the off-peak period, 0.66 percent during the a.m. peak period, and 1.23 percent during the p.m. peak period.
- Changes in emissions of hydrocarbons and reactive organic gases (HC and ROG), carbon monoxide (CO), and nitrous oxides (NOx). These range from a 0.21 percent decrease during the off-peak period (NOx) to a 2.88 percent increase during the p.m. peak period (CO).
The impacts on the regional roadway system of Phase 2 construction, which involved closure of one lane on the western six miles of I-496, were estimated through IDAS as follows:
- A decrease in VMT ranging from a 0.07 percent decrease during the off-peak period to 0.18 percent during the p.m. peak period and 0.25 percent during the a.m. peak period.
- An increase in both VHT and PHT of 0.07 percent during the off-peak period, 0.50 percent during the a.m. peak period, and 0.57 percent during the p.m. peak period.
- Decreases in average speed ranging from 0.22 percent during the off-peak period, 0.69 percent during the a.m. peak period, to 0.95 percent during the p.m. peak period.
- Decrease in the probability of the occurrence of fatality, injury, and PDO accidents due to reduced freeway travel. The values range from 0.21 percent decrease during the off-peak period to 1.49 percent decrease during the a.m. period.
- Decrease in fuel consumption of 0.10 percent during the off-peak period, 0.17 percent during the p.m. peak period, and 0.27 percent during the a.m. peak period (this may be attributed to a reduction in total VMT).
- Changes in emissions of hydrocarbons and reactive organic gases (HC and ROG), carbon monoxide (CO), and nitrous oxides (NOx). These changes were similar to those experienced during the Phase 1 construction period.
The total dollar impact of the I-496 reconstruction project on the transportation system in the Lansing region, without mitigation efforts, was estimated through IDAS to be $12,939,000. This impact was a result of the shifting of traffic from the Interstate to local arterials, which experience slower operating speeds. Most of this estimated loss resulted from increased travel time, but also included the effects of additional fuel consumption, increased accident-related costs, and degraded air quality. Nearly all of this estimated impact was a result of the Phase 1 closure. Dollar value of these impacts by time of day and construction phase is shown in Table 3.
Table 3. Lansing I-496 IDAS Evaluation Monetized Value of Construction Impact
|
Performance Measure |
Impact |
|---|---|
|
Construction Phase 1 |
-$12,810,000 |
|
AM Peak |
-$2,374,000 |
|
Off Peak |
-$2,263,000 |
|
PM Peak |
-$8,173,000 |
|
Construction Phase 2 |
-$129,000 |
|
AM Peak |
-$2,300 |
|
Off Peak |
$77,400 |
|
PM Peak |
-$204,400 |
Total |
-$12,939,000 |
The benefits of the Temporary Traffic Management System (TTMS) and associated activities are categorized into the following performance measures:
- User-mobility savings - Reported in hours of time saved by the traveling public, MDOT, and other agencies through the traveler information components of the TTMS, including the PDMS, web-based traveler information, video monitoring stations, and the telephone hotline information system;
- Travel time reliability savings - Reported in hours of unexpected delay saved by the traveling public, MDOT, and other agencies, primarily due to the incident management and information services rendered by the TTMS;
- Accident savings - Realized by MDOT, emergency response agencies, and the traveling public, primarily through the incident management services provided by the TTMS;
- Fuel consumption savings - For the traveling public and society, realized primarily through the incident management services, as well as the rest of the ITS services provided by the TTMS; and
- Emissions savings - To society resulting from all the services provided by the TTMS.
The overall results of the I-496 mitigation program, including both TTMS and arterial improvement program, are listed in Table 4. Overall the program provided $11 million in benefits at a cost of approximately $3.5 million. Thus, the net benefits of the program were $7.5 million, offsetting just under 60 percent of the $13 million project impact. A summary of total mitigation impacts is shown in Table 4.
Table 4. Project Benefit/Cost Summary
Total Benefits |
Cost |
|---|---|
|
Benefits of the TTMS and Public Information Campaign |
$9,467,179 |
|
Benefits of the Arterial Signal System Upgrades |
$1,526,837 |
|
Total Benefits of MDOT's Construction Mitigation Efforts |
$10,994,016 |
Total Costs |
|
|
Cost of the TTMS and Public Information Campaign |
$2,934,475 |
|
Cost of the Arterial Signal System Upgrades |
$500,000 |
|
Total Costs of MDOT's Construction Mitigation Efforts |
$3,434,475 |
|
Total Net Benefits |
$7,559,541 |
|
Total Benefit/Cost Ratio for MDOT's Construction Mitigation Efforts |
3.20:1 |
Results were calculated separately for the TTMS elements and the arterial signal improvements. It is important to note that most of the arterial signal improvements will provide ongoing benefits, while the TTMS was only deployed for the period of construction.
Key results are summarized for Phase 1 in Tables 5 and 6. The overall benefits for the Phase 1 TTMS was estimated at approximately $6.5 million, with the largest categories of benefit realized in travel time reliability ($1.67 million) and fuel savings ($2.04 million). Greatest benefits were realized during the off-peak and p.m. peak periods.
Table 5. Phase 1 TTMS Benefits Summary
|
Measure |
Time Period |
Impact |
Percent Reduction |
|---|---|---|---|
|
Mobility |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
115 hours 582 hours 166 hours |
Negligible Negligible Negligible |
Travel Time Reliability |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
50
hours 30 hours 409 hours |
-29.0% -30.0% -33.6% |
|
Fatality Reduction (Overall percentage) |
A.M., Off-, and P.M. Peak Periods |
2.20 percent | Same as impact |
|
Fuel Consumption Reduction (Average gallons reduced per day) |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
1,407 gallons 6,164 gallons 2,993 gallons |
-1.5% -1.4% -1.6% |
|
Emissions Reduction (Average tonnage reduction per day) |
A.M. Peak Period HC CO NOx |
0.029 tons 0.197 tons 0.070 tons |
-1.4% -1.5% -1.8% |
| Off-Peak Period HC CO NOx |
0.126 tons 0.869 tons 0.307 tons |
-1.3% -1.5% -1.6% |
|
| P.M.
Peak Period HC CO NOx |
0.061 tons 0.415 tons 0.148 tons |
-1.4% -1.5% -1.8% |
Table 6. TTMS Phase 1 Monetized Benefits in 2001 Dollars
Measure |
A.M.
Peak Period |
Off-Peak Period |
P.M. Peak Period |
Total |
|---|---|---|---|---|
Mobility Savings |
$ 128,691 | $ 649,726 | $ 185,858 | $ 964,275 |
Travel Time Reliability Savings |
165,810 | 138,872 | 1,369,702 | 1,674,384 |
Accidents Savings |
56,492 | 337,333 | 120,847 | 514,672 |
Fuel Consumption Savings |
223,627 | 1,335,940 | 475,710 | 2,035,277 |
Emissions Reduction Savings |
141,589 | 850,474 | 298,930 | 1,290,993 |
Total |
$ 716,209 | $ 3,312,346 | $ 2,451,047 | $ 6,479,601 |
Key results for Phase 2 are summarized in Tables 7 and 8. It can be noted that the benefits realized from the system exceeded the construction impact for Phase 2, thus providing an overall improvement to traffic in the region. The impact of the Phase 2 TTMS was just under $3 million, with approximately one-third of that total resulting from travel time reliability improvements. Benefits and costs for the arterial program were calculated separately from those of the TTMS. Approximately $900,000 in benefits were obtained during Phase 1, while just over $600,000 were achieved during Phase 2. Most of these benefits were in mobility savings and, in Phase 2, with travel time reliability. As is generally the case with arterial improvements, IDAS shows limited benefits in the areas of accident reduction, fuel savings, and air quality. Overall, the traffic signal system improvements resulted in a B/C ratio of 3.05:1 and proved to be very timely and effective in accommodating the additional traffic diverting to the alternate arterial corridors. Summaries of travel time savings and monetized impacts for both phases are shown in Tables 9 through12.
Table 7. Phase 2 TTMS Benefits Summary
|
Measure |
Time Period |
Impact |
Percent Reduction |
|---|---|---|---|
|
Mobility |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
44
hours 230 hours 65 hours |
Negligible Negligible Negligible |
Travel Time Reliability |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
119
hours 102 hours 500 hours |
-32.7% -33.9% -34.0% |
|
Fatality Reduction (Overall percentage) |
A.M., Off-, and P.M. Peak Periods |
2.23 percent | Same as impact |
|
Fuel Consumption Reduction (Average gallons reduced per day) |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
1,433 gallons 6,554 gallons 2,992 gallons |
-1.6% -1.5% -1.6% |
|
Emissions Reduction (Average tonnage reduction per day) |
A.M. Peak Period HC CO NOx |
0.028 tons 0.175 tons 0.066 tons |
-1.4% -1.6% -1.8% |
| Off-Peak Period HC CO NOx |
0.135 tons 0.911 tons 0.323 tons |
-1.4% -1.6% -1.7% |
|
| P.M.
Peak Period HC CO NOx |
0.062 tons 0.418 tons 0.147 tons |
-1.4% -1.6% -1.8% |
Table 8. TTMS Phase 2 Monetized Benefits in 2001 Dollars
Measure |
A.M.
Peak Period |
Off-Peak Period |
P.M. Peak Period |
Total |
|---|---|---|---|---|
Mobility Savings |
$ 48,976 | $ 257,343 | $ 72,983 | $ 379,302 |
Travel Time Reliability Savings |
158,772 | 185,702 | 669,999 | 1,014,474 |
Accidents Savings |
23,114 | 143,941 | 48,509 | 215,563 |
Fuel Consumption Savings |
91,071 | 568,127 | 190,199 | 849,397 |
Emissions Reduction Savings |
51,449 | 357,367 | 120,027 | 528,842 |
Total |
$ 373,381 | $ 1,512,481 | $ 1,101,716 | $ 2,987,578 |
Table 9. Phase 1 Arterial Benefits Summary (for Time Savings Only)
|
Measure |
Time Period | Impact | Percent Reduction |
|---|---|---|---|
|
Mobility |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
286 hours 344 hours 1,044 hours |
-0.7% -0.2% -1.3% |
Travel Time Reliability |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
6 hours 1 hours 67 hours |
-3.3% -1.2% -5.5% |
Table 10. Arterial Phase 1 Monetized Benefits in 2001 Dollars
Measure |
A.M.
Peak Period |
Off-Peak Period |
P.M. Peak Period |
Total |
|---|---|---|---|---|
Mobility Savings |
$ 90,555 | $ 139,147 | $ 326,930 | $ 556,633 |
Travel Time Reliability Savings |
7,597 | 2,203 | 89,228 | 99,028 |
Accidents Savings |
14,540 | 24,362 | 58,905 | 97,807 |
Fuel Consumption Savings |
11,589 | 17,576 | 45,865 | 75,030 |
Emissions Reduction Savings |
12,218 | 19,800 | 44,183 | 76,201 |
Total |
$ 136,499 | $ 203,088 | $ 2,451,047 | $ 904,698 |
Table 11. Phase 2 Arterial Impacts Summary (for Time Savings Only)
|
Measure |
Time Period | Impact | Percent Reduction |
|---|---|---|---|
|
Mobility |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
150
hours 173 hours 566 hours |
-0.4% -0.1% -0.7% |
Travel Time Reliability |
A.M. Peak Period Off-Peak Period P.M. Peak Period |
37
hours 13 hours 87 hours |
-10.3% -4.2% -5.9% |
Table 12. Arterial Phase 2 Monetized Benefits in 2001 Dollars
Measure |
A.M.
Peak Period |
Off-Peak Period |
P.M. Peak Period |
Total |
|---|---|---|---|---|
Mobility Savings |
$ 46,799 | $ 64,020 | $ 179,300 | $ 290,119 |
Travel Time Reliability Savings |
49,839 | 22,870 | 117,043 | 189,753 |
Accidents Savings |
9,206 | 26,990 | 31,320 | 67,515 |
Fuel Consumption Savings |
5,496 | 9,016 | 19,764 | 34,275 |
Emissions Reduction Savings |
6,850 | 9,083 | 24,543 | 40,476 |
Total |
$ 118,190 | $ 131,979 | $ 371,970 | $ 622,139 |
Recommendations for the Project
Based on the analysis, the following recommendations were provided for consideration by MDOT:
- The TTMS deployment was found to be beneficial and effective in achieving its stated goals. It was recommended that MDOT consider the use of TTMS in the future for construction traffic management.
- For major construction projects MDOT should evaluate the cost-effectiveness of various traffic management systems, including portable ITS systems. IDAS provides a method of assessing the benefits and costs of different investment levels. Cost effectiveness will vary depending on the nature of the construction project and the volume of traffic impacted.
- IDAS evaluations of systems, such as the TTMS, can be improved by adjusting the impact assumptions based on additional, empirical information. Sources available for the Lansing I-496 project include the public surveys conducted by MDOT during and after the construction projects as part of the public awareness and response campaign for the I-496 reconstruction project and actual traffic data (traffic volumes, travel times, diversion patterns) collected by the system and by MDOT personnel during the course of the TTMS operations.
- It was also recommended that MDOT use the data collected by the systems for future planning, decision-making, traffic operations optimization, and research purposes.
- It was recommended that deployment of systems for Temporary Traffic Management should be coordinated with the regional transportation plan. MDOT may consider making some elements of the system permanent if they are part of an adopted regional plan.
Lessons Learned
These are lessons learned from the implementation of IDAS for the TTMS in Lansing, Michigan.
1. The availability of a regional travel demand model already updated for the base year travel was very important to the success and credibility of the analysis.
2. The use of impact values from local sources better represented conditions in the Lansing region than the national default values available within IDAS. The default values are not necessarily reflective of smaller to mid-sized urban areas. As more information on ITS deployment in these areas is collected, it needs to be disseminated as widely as possible.
3. It is important to account for all cost components and elements of the program. This project started as an evaluation of the TTMS, but in the early stages of the project it became clear that the arterial system improvements and the public relations campaign were critical to the success of the project, and they were incorporated into the analysis.
4. IDAS has demonstrated value in the evaluation of ITS alternatives for mitigation of major construction projects.
5. Adequate time must be provided to accommodate review by different departments. Even a relatively small evaluation project such as this one may require review by a number of different agencies and departments within those agencies. This is needed so that the assumptions are accepted and that the deployments and operational strategies in place are reflected accurately in IDAS.
Project Cost and Schedule
The draft report for this evaluation was completed in approximately four months. Following a review meeting with MDOT management, some modifications were made and the final report was resubmitted. The cost of the evaluation work was just under $30,000. It should be noted that this cost was reduced because the same IDAS model was used for the MDOT ITS Pre-Deployment Study and costs were shared between the two projects. Specific tasks included:
- Initial meetings with key agency staff;
- Review of plans for the ITS systems;
- Incorporation of model into IDAS;
- Running base year and construction impact scenarios;
- Setup and coding of ITS deployments into the IDAS model;
- Development of draft report;
- Review of results with client; and
- Final report and presentation.
Future Usage of Data and/or Technical Approaches Developed
There are several ongoing efforts related to ITS deployment in the Lansing region. A regional architecture was recently completed and plans are going forward for an arterial traffic management center to serve the City of Lansing. It is possible this center will also serve adjacent municipalities and future MDOT deployments, which are being developed through the MDOT ITS Pre-Deployment Study. The Tri-County Regional Planning Commission is also adopting an ITS element into its long-range plan, that identifies regional priorities at a high level.
In addition to the Traffic Management Center, ITS opportunities in the region include:
- A freeway management system that would provide surveillance and information at key decision points, primarily for incident management purposes;
- Improved signal coordination on major arterial corridors across municipal boundaries;
- Advanced warning systems at key railroad grade crossings;
- Incorporation of automated vehicle location (AVL) and advanced traveler information technologies into the operation of CATA, the regional public transportation provider;
- Parking information systems for the State Capitol complex and the Michigan State University (MSU) campus; and
- Increased use of technology for transportation management at special events, particularly major MSU sporting events.
As mentioned earlier, the Tri-County Regional Planning Commission recently updated its base-year travel demand model and is currently developing future year networks. They will be obtaining IDAS in the near future and will be able to evaluate individual elements of the regional ITS plan as they are developed in greater detail. A partnering opportunity exists to work with MSU to analyze available data for further calibration of the IDAS model.
It is also important to note that ITS deployments may be accomplished in concert with other major road and bridge projects. IDAS provides the opportunity to evaluate the potential benefits of incorporating ITS into build alternatives.
This is one of four case studies describing the application of the ITS Deployment Analysis System (IDAS) software program. These case studies illustrate innovative approaches in conducting ITS planning and program development.
Contacts
This work was performed under contract with:
Federal Highway Administration
Planning and Environment
Office of Metropolitan Planning and Programs
400 7th Street, S.W.
Washington, D.C. 20590
The Case Study was prepared by:
Cambridge Systematics, Inc.
1300 Clay St., Suite 1010
Oakland, CA 94611
Telephone: (510) 873-8700
Fax: (510) 873-8701
Web: http://www.camsys.com
For further information, please contact:
Kunwar Rajendra,
Ph.D., P.E.
ITS Engineer
Michigan Department of Transportation
425 W. Ottawa Street
P.O. Box 30050
Lansing, Michigan 48909
Telephone: (517) 335-2893
Fax: (517) 373-9255
E-mail: rajendrak@michigan.gov