Analysis of Road Weather Information System Enhancements and Expansion in Montana Estimated to Save up to $2.2 Million in Crash Occurrence and Delay Costs.

Study Conducted Benefit-Cost Analyses for Several Scenarios to Quantify Potential Agency and Societal Benefits.

Date Posted
08/30/2021
Identifier
2021-B01589
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Assessment of Montana Road Weather Information System (RWIS)

Summary Information

Road Weather Information Systems (RWIS) have been developed by transportation agencies to address operational and safety challenges associated with weather. Researchers conducted a comprehensive review and assessment of Montana DOT’s RWIS program, which includes 73 RWIS stations throughout the state, to assess needs and compare expansion and enhancement scenarios. The goal of the study was to ensure the efficient use of weather data in various transportation applications and the optimum use of agency resources.

Methodology

After performing a needs assessment and weather data and software analysis, researchers conducted a benefit-cost analysis to investigate outcomes related to using different software functionalities and geographic expansion alternatives. The current RWIS coverage with observational software functionalities was used as the baseline. Each alternative scenario was then evaluated relative to the existing baseline situation. In general, benefit quantities were based on prior studies and conservative values are used. The net present value of the benefits and costs for all scenarios are determined using a 10-year period and a 7% discount rate, with all hardware having an assumed 10-year life cycle. A range of benefit cost ratios are estimated for each scenario using both the agency-specific benefits and total (agency and societal) benefits in comparison to a range of costs (estimated minimum to maximum). The following scenarios were identified for analysis in consultation with agency staff:

  • Scenario 1 (Observational + Alerting, No Expansion): Using the current RWIS sites with a software system capable of providing customizable alerts for different weather conditions as well as for unresponsive or malfunctioning sensors and sites.
  • Scenario 2 (Observational + Forecasting/maintenance decision support systems (MDSS), No Expansion): Using the current RWIS sites with a software system and service capable of providing detailed atmospheric and pavement forecasts along with some decision support capability to provide treatment recommendations based on the forecasts.
  • Scenario 3 (Observational + Performance Measures, No Expansion): Using the current RWIS sites with a software system and service capable of providing automated performance measures information.
  • Scenario A (Observational, Base Expansion): Using the current observational software with the current RWIS sites and 18 additional “base” RWIS sites which are configured to include the same equipment as the majority of current sites.
  • Scenario B (Observational, Simple Expansion): Using the current observational software with the current RWIS sites and 18 additional “simple” RWIS sites which are configured to include only a camera and pavement temperature sensor.
  • Scenario C (Observational, Non-Invasive Expansion): Using the current observational software with the current RWIS sites and 18 additional RWIS sites that use non-invasive sensors instead of in-pavement sensors.
  • Scenario D (Observational, Mobile Expansion): Using the current RWIS sites and 12 additional mobile RWIS sites including a software system that supports mobile RWIS sensors.

Findings

Table 1 summarizes the benefits of each scenario and selection combinations as compared to Montana’s existing RWIS baseline situation. Monetary annual benefits in terms of reduced labor are as high as $1,922,175; reduced material as high as $543,500; reduced crash occurrence as high as $1,806,227; reduced delay as high as $430,024; and the total benefit/cost (B/C) ratio as high as 36. While the best estimates available were used throughout the analysis, researchers noted that many individual costs and benefits have a limited amount of known data.

Table 1. Summary of Monetized Annual RWIS Benefits (year 2016 dollars)

Scenarios

Agency Benefit: Reduced Labor

Agency Benefit: Reduced Material

Societal Benefit: Reduced Crash Occurrence

Societal Benefit: Reduced Delay

Estimated Agency B/C Ratio

Estimated Total (Agency and Societal) B/C Ratio

1

$16,575

-

$38,632

$4,865

0.3 - 5.7

1 - 20.6

2

$1,910,000

$434,800

$390,520

$90,905

17.1 - 29.8

20.5 - 36

3

-

$543,500

$1,620,000

$385,727

4.8-17.9

21.8-33.3

A

$12,175

-

$186,227

$44,297

0.06 - 0.09

 

1.2-1.8

B

$12,175

-

$186,227

$44,297

0.11 - 0.18

2.1-3.6

C

$12,175

-

$186,227

$44,297

0.05 - 0.07

1.0-1.4

D

$0

-

$186,227

$44,297

No quantified benefits

1.4-2.9

1+A

$28,750

-

$224,859

$49,162

0.1 - 0.2

1.1-2.2

1+B

$28,750

-

$224,859

$49,162

0.2 - 0.4

1.6-4.3

1+C

$28,750

-

$224,859

$49,162

0.1 - 0.2

 

1-1.7

1+D

$16,575

-

$224,859

$49,162

0.1 - 0.2

1.8-3.7

2+A

$1,922,175

$434,800

$576,747

$135,202

5.7 - 8.5

7.9-11.6

2+B

$1,922,175

$434,800

$576,747

$135,202

6.9 - 12.2

9.5-16.8

2+C

$1,922,175

$434,800

$576,747

$135,202

4.8 - 7.3

6.6-10

2+D

$1,910,000

$434,800

$576,747

$135,202

10.5

14.5

3+A

$12,175

$543,500

$1,806,227

$430,024

1.7 - 2.1 (without forecasting);

6.7 - 8.2 (with forecasting)

 

8.4-10.3 (without forecasting);

13.1-15.9 (with forecasting)

3+B

$12,175

$543,500

$372,454

$88,594

2.3 - 2.8 (without forecasting);

8.9 - 10.7 (with forecasting)

11.2-13.8 (without forecasting);

17.3-20.9 (with forecasting)

3+C

$12,175

$543,500

$372,454

$88,594

3.7 - 4.5 (without forecasting);

6.1 - 7.2 (with forecasting)

15.1-18.1 (without forecasting);

17-20.2 (with forecasting)

3+D

$0

$543,500

$372,454

$88,594

3.2 (without forecasting);

10.1 (with forecasting)

12.7 (without forecasting);

19.7 (with forecasting

 

 

Results Type
Deployment Locations