Appendix A: Worked Example - Economic appraisal of household/community program

Program details

A household/community travel behaviour change program is being considered for a suburb in a large city (> 1 million population) to encourage residents to use modes other than their private cars for some of their trips. The total population of the target suburb is 10,000 people. The objectives of the proposed initiative are to reduce pressure on road capacity and the environment by reducing car use and to encourage people to choose active travel modes such as cycling and walking for some trips, complementing other programs promoting the health benefits of increased physical activity.

Location: Large city > 1 million population

Total population of target area: 10,000

TBhC program costs:

  • Year 1: Program implementation - $2.5 million
  • Years 2 -10: Ongoing support - $0.2 million per annum

Example appraisal

Select diversion rate profile

  Car as driver Car as dassenger PT Cycling Walking
Standard -3.1% -0.5% 1.4% 0.9% 1.3%

Proportion of diverted trips in off-peak: 85%

Proportion of diverted trips to CBD: 10%

Collate trip lengths

Collate relevant trip lengths (such as default values from Table 8) and calculate weighted averages.

  Peak 15% Off peak 85% Weighted average (km)
Car driver 10.0 8.0 8.3
Car passener 9.0 7.5 7.7
public transport 12.0 11.0 11.2
cycle 5.0 4.5 4.6
walk 2.0 2.0 2.0

Household programs target all trips (not just trips to/from CBD)

Collate parameter unit values

Obtain unit values for unperceived costs (resource cost corrections) and externalities from Table 7 and calculate weighted averages incorporating peak/off peak and CBD/other destination.

    Peak
15%
Off peak
85%
Weighted
average
(cents)
Weighted
average
($)
Car driver per km          
VOC RCC   0 0    
Net congestion ext   42.5 11.5    
Accident ext   8.7 8.7    
Environmental ext   6.2 6.2    
Total per km   57.4 26.4 31.1 0.311
per trip          
Parking RCC (trips to CBD) 10% 200 100    
Parking RCC (trips other) 90% 50 25    
Total per trip       37.38 0.374
Car passenger per km          
VOC RCC   0 0    
Net congestion ext   21.25 5.75    
Accident ext   4.35 4.35    
Environmental ext   3.1 3.1    
Total per km   28.7 13.2 15.5 0.155
per trip          
Parking RCC   0 0    
Total per trip   0 0 0 0
Public transport passenger per km          
Ace ident costs   0 0    
Environmental costs   0 0    
Total per km   0 0 0 0
per trip          
Fare resource cost correction   -300 -300    
Total per trip   -300 -300 -300 -3.00
Cycling per km          
Ace ident costs   0 0    
Health effect   -73 -73    
Total per km   -73 -73 -73 ~ 73
Walking per km          
Ace ident costs   0 0    
Health effect   -145 -145    
Total per km   -145 -145 -145 -1.45

Positive values indicate an unperceived resource cost; negative values indicate an unperceived resource cost saving (benefit). Per kilometre unit values for car passenger are set at 50% of car driver values based on a proportion of trips being undertaken specifically for the passenger.

Calculate total unperceived costs and benefits for each trip type

The following table combines the steps described in Sections 5.5.2, 5.5.5 and 5.5.6 and calculates the total resource cost correction and externality benefits per day for each former and new mode.

Benefit from avoided car driver trips which change to: Diversion rate
A
Diverted trips per day
B = (Ax PopxTrips)
Trip length
C
per km costs
D
per trip costs
E
total costs ($)
F = (CxD+E)
Benefits/day
G = (BxF)
public transport trip -1.21% 362 11.2 0.311 0.374 3.84 1387
cycle trip -0.78% 233 4.6 0.311 0.374 1.79 417
walking trip -1.12% 336 2.0 0.311 0.374 0.99 334
Sub Total -3.10%           2139
Benefit from avoided car passenger trips which change to: Diversion rate Diverted trips per day Trip length per km costs per trip costs total costs ($) Benefits/day
public transport trip -0.19% 58 11.2 0.155 0 1.73 101
cycle trip -0.13% 38 4.6 0.155 0 0.71 27
walking trip -0.18% 54 2.0 0.155 0 0.31 17
Sub Total -0.50%           144
Cost of trips undertaken on new mode of: Diversion rate Diverted trips per day Trip length per km costs per trip costs total costs ($) Costs/day
public transport 1.40% 420 11.2 0.000 -3.00 -3.00 -1260
cycle 0.90% 270 4.6 -0.730 0 -3.34 -902
walk 1.30% 390 2.0 -1.450 0 -2.90 -1131
Sub Total 3.60%           -3293

click to enlarge

Calculate mode changer perceived net benefits

The following table shows the calculation of the mode changer perceived net benefits as described in Section 5.5.7.

Benefits to mode changers for: Diversion rate A Diverted trips per day B = (Ax PopxTrips) Diversion C Rate per 1% from Table 6 D Benefit per person per trip E = (100xCxD) Benefits/day F = (BxE)
car driver/passenger to public transport 1.4% 420 1.4% $0.35 0.49 206
cardriver/passenger to cycle 0.9% 270 0.9% $0.25 0.23 61
car driver/passenger to walk 1.3% 390 1.3% $0.25 0.33 127
Sub Total 3.6%         393

click to enlarge

Calculate total benefits per day

Add:

RCC and externality costs associated with avoided car driver trips - $2,139

RCC and externality costs associated with avoided car passenger trips - $144

Subtotal - $2,283

Subtract:

RCC and externality costs associated with trips on the new modes ‑ $3,293

Subtotal (note subtracting a negative cost adds to benefits) - $5,576

Add:

Mode changer perceived net benefits - $393

Total benefit per day - $5,969

Calculate total benefits per year

Multiply the total benefits per day by an appropriate annualisation factor (Section 5.5.9).

Total benefits per year = $5,969 x 365 = $2.179 million

Calculate NPV and BCR

Discount rate -7% Cost ($0'00) Benefit ($'000)
Year 1   PV   PV
1 0.935 2500 2336 0 0
2 0.873 200 175 2179 1903
3 0.816 200 163 2179 1778
4 0.763 200 153 2179 1662
5 0.713 200 143 2179 1553
6 0.666 200 133 2179 1452
7 0.623 200 125 2179 1357
8 0.582 200 116 2179 1268
9 0.544 200 109 2179 1185
10 0.508 200 102 2179 1108
Total       3554 13266

Net present value = 13.266M – 3.554M = $9.71 million

Benefit/cost ratio = 13.266/3.554 = 3.7