VEHICLE TRIP GENERATION FROM RETAIL, OFFICE AND RESIDENTIAL
DEVELOPMENTS
Dr D. O’Cinneide and R. Grealy
University College Cork, Ireland
1. INTRODUCTION
The traffic impacts of a new development depend mainly on the number of
vehicles generated and on the capacity on the road and public transport
networks. Consequently, each proposed development has unique characteristics.
In applying for planning permission, traffic predictions typically use databanks
such as TRICS (www.trics.org). These databanks are based on traffic counts at
many existing developments and they are assumed to give reliable estimates of
traffic volumes. However, little independent verification is available and
substantial differences between the predicted and measured traffic volumes are
not uncommon.
In this paper, trip generation studies taken by students at University College Cork
over a number of years are used to identify the principal factors which determine
the volume of traffic from the three most common types of development in
Ireland; retail food superstores, offices and residential developments.
Comparisons are made with results derived from the TRICS databank.
2. TRAFFIC IMPACT ASSESSMENT
Predicting the traffic impact of a proposed development involves:
1. Quantification of the local road and public transport networks; traffic flows,
capacities, queue lengths, safety, etc.
2. Quantification of the number and distribution of the additional trips
generated by the proposed development
3. Appraisal of the impact of these additional trips on the road and public
transport networks
Although trips by all modes of transport are included, vehicle trips normally
contribute the most significant impacts.
Based on the literature, the performance indicators shown on Table 1 are
suggested for quantifying the traffic impacts of a proposed development. The
environmental impacts resulting from additional traffic are not included. Methods
of quantifying each performance indicator are also indicated in Table 1. These
methods use UK traffic models (www.trlsoftware.co.uk; www.sias.com) since
studies carried out at University College Cork have indicated that UK traffic
models are applicable in Ireland (Grealy 2006, O’Cinneide and O’Mahony 2005).
© Association for European Transport and contributors 2008
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Table 1: Performance indicators for measuring the traffic impact of developments
Traffic impact
Performance indicator
Method of measurement
parameter
Area and individual junction
Congestion
Queue lengths: Predicted
simulation models such as
changes in queue lengths at
Paramics, OSCADY,
significant junctions
ARCADY
Delay: Predicted changes in
delay at significant junctions
Junction models such as
Safety
Number of serious and minor OSCADY or ARCADY and/or
network accident prediction
injury accidents: Predicted
models such as SafeNET2
changes in the number of
serious and minor accidents
on adjacent road links and
junctions.
Vulnerable
road users
Predicted change in delay
when crossing at significant
junctions
Area and individual junction
models such as Paramics and
OSCADY
The performance indicators shown on Table 1 depend on the type and size of a
proposed development, on the traffic generated and on the surrounding road
network before and after the development. Since network conditions are site
specific, this paper only considers the trip generation from developments.
3. THE SELECTION OF LAND USES FOR DETAILED INVESTIGATION
The main criteria for the selection of the land uses for detailed study were:
1. The most common types of developments in Ireland.
2. Ease of obtaining the required site information, traffic counts, etc.
In recent years most new developments in Ireland can be categorised under land
use categories: Retail, Office Block and Residential or as a mix of these land use
categories. Each category generates different types of trips (work trips,
commercial trips, home trips, etc.). Also, most of the trips from these land uses
are distributed to the other two land uses. The locations are also influenced by
the locations of the other two categories.
© Association for European Transport and contributors 2008
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4. TRIP GENERATION CASE STUDIES
4.1 Traffic Counts at Selected Land Uses in the Cork Region
The principal traffic impacts from a new development occur during peak traffic
periods on the adjacent road network. Additional vehicles have a particularly
severe effect if the network has exceeded capacity. Consequently, the traffic
counts described in this paper are the number of vehicles by type entering and
leaving existing developments during the morning (8.00-9.00) and / or evening
(17.00-18.00) peak traffic periods. These counts were taken at various times
from 2004 to 2007. For further details see Grealy 2006.
4.2 Retail Development Counts
These were restricted to food stores only. Food stores are divided into two subcategories; food superstores and discount food stores because substantially
higher trip rates were expected from the later. Food superstores vary from standalone developments, to those which include non-food elements, and to stores
which are part of larger shopping centres. A number of different sizes and types
of food store in the Cork area were selected for trip rate analysis. Table 2 shows
the details and the measured light vehicle trip rates (per 100m2 gross floor area)
for each development studied. Apart from Tesco Wilton, which remained open for
24 hours, these stores opened at 9.00 hours and closed after 19.00 hours when
the counts were taken. Counts were limited to suburban food stores because of
the difficulty in quantifying vehicle trip rates for city centre food stores.
•
Food superstores with non-food sections
The total evening peak hour (17.00-18.00) trip rates for Dunnes, Bishopstown
Court and for Dunnes Stores Ballyvolane were fairly similar. These are similar
food superstores with similar characteristics regarding the surrounding road
networks and the population within a 17- minute travel time.
•
Food superstores which are part of larger shopping centres
The total evening peak hour (17.00-18.00) trip rate for Wilton Shopping Centre
was marginally higher than at the slightly smaller Douglas Court Shopping
Centre. These shopping centres have similar populations within a 17 minute
travel time and the Cork South Ring Road (N25) is located adjacent to both
shopping centres. Both developments were similar with each having banks,
restaurants and commercial units.
•
Stand alone food superstores / discount food stores
The measured evening peak trip rates were substantially higher than for food
superstores with non-food sections or for superstores in shopping centres.
© Association for European Transport and contributors 2008
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The total evening peak hour trip rate for Lidl, Togher in 2004 was 21.96
veh/100m2 while counts at the same development in 2002 showed a total
evening peak hour trip rate of 19.44 veh/100m2.
Table 2 Food superstores in the Cork area selected for trip rate analysis
Name
Location and type
Size
Time
Trip rates (light
m2
vehicles per 100m2
GFA*
GFA*
In
Out
Total
1.22
0.25
0.97
7189
8-9
Suburban
Dunnes,
Bishopstown foodstore with non8.71
3.91
17-18 4.80
food section
Court, Cork
6520
Suburban
Dunnes,
Ballyvolane, foodstore with non9.50
4.65
17-18 4.85
food section
Cork
3.03
1.33
1.70
Suburban
16462
8-9
Dunnes,
shopping centre
Douglas
7.62
4.49
17-18 3.13
Court Centre
3.90
1.95
1.95
Suburban
17656
8-9
Tesco
shopping centre
Wilton
7.86
4.63
17-18 3.23
Centre
1.94
0.51
1.43
Satellite town
1960
8-9
SuperValu
foodstore
Ballincollig,
20.66
17-18 11.02 9.64
Co. Cork
1.84
0.34
1.50
Lidl, Togher, Suburban discount 1471
8-9
Cork
foodstore
17-18 11.08 10.88 21.96
Co. Cork town
1610
Lidl,
discount foodstore
Midleton,
16.89
8.57
17-18 8.32
Co. Cork
* GFA = Gross Floor Area; the sum of the areas of all the floors of a building
•
Relationship between size of food stores and trip rates
From Table 2 it can be seen that a decrease in the size of a development
normally results in an increase in the total evening peak hour trip rate.
SuperValu, Ballincollig (a satellite town food store) was only 27% the size of
Dunnes, Bishopstown Court. However, the total evening peak hour vehicular
movement at SuperValu Ballincollig was 65% of that at Bishopstown Court. The
substantially higher trip rate was partly due to the lack of competition in the
surrounding area; the only competition was a discount food store at the opposite
end of the town.
© Association for European Transport and contributors 2008
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Table 2 shows that that the similar sized Wilton and Douglas Court Shopping
Centres have almost the same total evening peak hour trip rates. Wilton and
Douglas Court Shopping Centres have:
o Similar populations within a 17-minute travel time.
o A similar development located within a mile.
o The Cork South Ring Road (N25) is adjacent
The gross floor area of Lidl, Togher is 8.6% smaller than that of Lidl, Midleton but
the total evening peak hour trip rate for Lidl Togher was 30% higher than that for
Lidl, Midleton. The probable reason for Lidl Togher having a higher evening peak
hour trip rates is the adjacent population. The population within a mile of Lidl,
Midleton is substantially less than that of Lidl, Togher.
From the studies of the food superstores, three general conclusions are drawn:
1. The lack of similar developments in an area result in high trip rates
2. The smaller the foodstore, the higher the trip rate.
3. Similar developments with similar populations, road networks and competition
have similar evening peak hour trip rates.
4.3 Office Block Development Counts
The office blocks selected for analysis are shown on Table 3. The gross floor
area (GFA) in this table includes occupied office blocks only.
Table 3. Offices in the Cork area selected for trip rate analysis
Name
Location
Type
Size
Time
Trip rate (light
m2
vehicles / 100m2)
GFA
In
Out Total
1.49 0.09 1.58
Suburban
Single
4393 8-9
Jacobs
company
Engineering,
17-18 0.15 1.53 1.68
Mahon,
Cork
Suburban
4 office
11000 8-9
1.45 0.12 1.57
University
blocks
Technology
Centre,
Curaheen
Rd., Cork
3.33 0.14 3.47
RPS-MCOS, Satellite
Single
1408 8-9
Ballincollig,
town
company
17-18 0.07 1.56 1.63
Occupied 37161 8.00- 1.63 0.10 1.73
Cork Airport Cork
9.00
Airport
office
Business
blocks
Park
© Association for European Transport and contributors 2008
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Two trip rate parameters are used to express office block trip rates; the size of
the office block and the number of employees. When using size as a trip rate
parameter, the entire development must be in operation to ensure a useful
measured trip rate. The number of employees would appear to be a suitable trip
rate parameter, particularly if most employees remain in the office all day and
work similar hours. A detailed investigation into the two engineering consultancy
companies studied (Jacobs Engineering and RPS-MCOS) showed that both had
similar morning vehicle peak hour trip rates per employee; Jacobs Engineering
(166 employees) had a trip rate of 0.56 light vehicles per employee compared
with 0.43 at RPS-MCOS (88 employees). However, the evening peak hour trip
rate per employee at Jacobs Engineering (0.46) was substantially higher than at
RPS-MCOS (0.26). This difference resulted mainly from the proportions of the
employees traveling to external sites during the day and from the proportions
working beyond 18.00 hours. This suggests that the number of employees may
not be a suitable trip rate parameter. Also, it is difficult to predict the number of
employees in a proposed office block development. Consequently, the trip rates
shown in Table 3 are in terms of trips per 100 m2 of gross floor area.
From Table 3 it can be seen that the morning peak hour trip rates per 100 m2
gross floor area were fairly similar for 3 of the 4 office blocks studied. However,
the trip rate at RPS-MCOS was about twice that of the other blocks. Only part of
this difference was due to employees arriving before the morning peak hour.
It is difficult to draw reliable conclusions from these office block studies. The
differences in the measured vehicle trip rates could not be explained by
differences in the modal split (almost all the employees used a car), or by
differences in arrivals/departures before or after the peak hours. The type of
business being carried out appeared to significantly affect the trip rates.
4.4 Residential Development Counts
The most common types of residential developments in Ireland are single family
isolated dwellings in rural areas, suburban or ex-urban housing estates with 3/4/5
bed dwellings or apartment blocks in cities and towns. The residential
developments studied and the measured morning peak hour (8.00-9.00) car trip
rates are shown on Table 4. The number of heavy vehicles was minimal.
The measured car trip rates for the morning peak hour varied from 0.27 to 1.65
trips/household; 75% - 80% of the vehicles were departing.
The principal factors which influenced the morning peak hour trip rates were the
type and number of occupants (wealth, employment, age), the car ownership
level and the location. The social status and employment of the occupants were
strongly related to the car ownership levels. The location of a residential
development influenced both the type of occupant and the car ownership level.
© Association for European Transport and contributors 2008
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Table 4. Residential development morning peak hour (8.00-9.00) trip rates.
Name
No. of
Type
Car trips per
households
household
In
Out Total
Broadale, Maryborough 356
4-5 bed semi +
0.18 0.73 0.91
Hill, Cork
detached
Knockrea Park,
58
3 + 4 bed semi
0.62 0.29 0.91
Ballinlough, Cork
+ detached
Heatherfield, Waterfall,
43
5 bed detached 0.00 1.08 1.08
near Cork
0.25 0.86 1.16
Ferndale, Carrigaline,
74
3 / 4 bed semi
0.13 1.14 1.27
Co. Cork
detached
Park Gate, Frankfield,
295
3 / 4 bed semi
0.89
Cork
detached
Mount Oval,
26
Detached
0.26 0.86 1.12
Rochestown, Cork
Shamrock Lawn,
489
3 / 4 bed semi
0.93
Douglas, Cork
detached
Deerpark, Cork
98
Town houses
0.09 0.85 0.94
Haldene, Bishopstown, 64
3 / 4 bed semi
0.18 0.74 0.92
Cork
detached
Willowbank, Church Rd. 103
Semi detached
0.31 0.80 1.11
Blackrock, Cork
Cloghroe, Co. Cork
29
Semi detached
1.17
Outskirts of Bantry, Co. 25
Mix detached + 0.20 0.52 0.72
Cork
semi detached
Norwood, Cobh, Co.
180
3 / 4 bed semi
n/a
n/a
0.76
Cork
detached
Carraigroe,
67
Apartments
0.10 0.27 0.37
Mitchelstown, Co. Cork
(immigrants)
Oakwood, Macroom,
110
3 / 4 bed terrace 0.05 0.22 0.27
Co. Cork
(immigrants)
Woodfield, Killeagh, Co. 55
10 semi + 45
0.07 0.43 0.45
Cork
detached
Ballinacurra, Midleton,
56
Detached
0.00 0.45 0.45
Co. Cork
Crookstown, Co. Cork
65
Semi detached
0.42
Woodside, Ballynora,
13
Detached
0.23 0.77 1.00
Cork
Mardyke Walk, Cork
59
Mix of house
0.53
types
Culrua, Portlaw, Co.
81
Semidetached
0.59 0.22 0.81
Waterford
26
Semi +detached 0.40 1.25 1.65
Carystown Woods,
83
Mix of house
0.15 0.64 0.78
Whitegate, Co. Cork
types
© Association for European Transport and contributors 2008
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Table 5 shows the median and range of the total morning peak hour trip rates for
the observed developments divided by location into Inner City / Town, Cork City
Suburbs, Rural Areas on the edge of Cork City, and County Cork towns.
Inner City: Areas within a feasible walking distance (<1km) of the city/town
centre
Suburbs: Areas within a feasible walking distance of a Cork City Bus Service
but outside a feasible walking distance of the city centre
Rural Areas: Areas with little public transport service and outside a feasible
walking distance of the city centre
Table 5 Total morning peak hour (8.00-9.00) car trip rates by location
Location
Median car trip
Range
rate / household
Inner city /
0.53
0.27 – 0.94
town
Suburbs of
0.94
0.89 – 1.11
Cork City
Rural areas
1.11
1.00 – 1.27
County towns 0.69
0.42 – 1.65
Morning peak hour trip rates for inner city / town developments were generally
lower than for suburban or rural developments. The ratio of cars/household was
well below 1.00 for all but one of these inner city developments (Deerpark). Many
occupants were retired people or tenants with restricted budgets such as recent
immigrants.
5. THE ACCURACY OF EXISTING METHODS OF TRIP RATE CALCULATION
The most frequently used database for predicting trip rates in Ireland and the UK
is TRICS (www.trics.org) which is a large database based on traffic counts from a
large number of sites throughout Great Britain and Ireland and is updated
regularly. However, most data is from the south east of England.
The TRICS land use categories are divided into 16 main categories which are
further divided into sub-categories. Trip rates for each sub-category type are
given as the number of vehicle or person arrivals and departures per 100m2
gross floor area, number of employees, households, etc., and can be used to
predict the traffic/people flows in and out of proposed developments by half hour
of the day and day of the week. TRICS trip rates are compared with the
measured trip rates in the following pages.
© Association for European Transport and contributors 2008
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5.1 Comparison between Observed and Predicted Trip Rates for Retail
Developments
Table 6 shows the calculated TRICS trip rates and the measured trip rates for the
evening peak hour (17.00 -18.00) for the food stores studied.
Table 6. TRICS trip rates and measured rates for food stores (17.00 -18.00)
Name
Location and
Trip rates (light vehicles per 100m2
type
GFA
In
Out
Total
Suburban
Dunnes,
Observed 4.80
3.91
8.71
Bishopstown foodstore with TRICS
6.47
6.48
12.95
non-food
Court, Cork
section
Suburban
Dunnes,
Observed 4.85
4.65
9.50
Ballyvolane, foodstore with TRICS
6.47
6.48
12.95
non-food
Cork
section
Dunnes,
Douglas
Court Centre
Tesco
Wilton
Centre
Suburban
shopping
centre
Suburban
shoping
centre
Observed
TRICS
3.13
4.49
7.62
6.32
Observed
TRICS
3.23
4.63
7.86
6.32
SuperValu
Ballincollig,
Co. Cork
Satellite town
foodstore
Observed
TRICS
11.02
3.32
9.64
3.64
20.66
6.96
Lidl, Togher,
Cork
Suburban
discount
foodstore
Co.Cork town
discount
foodstore
Observed
TRICS
11.08
3.32
10.88
3.64
21.96
6.96
Observed
TRICS
8.32
3.32
8.57
3.64
16.89
6.96
Lidl,
Midleton,
Co. Cork
For food superstores with non- food sections, the gross floor area used for
TRICS was similar to that of the foodstores studied. However, the predicted trip
rates were considerably higher than the measured trip rates.
For food superstores which are part of larger shopping centres (Douglas Court
Shopping Centre and Wilton Shopping Centre), TRICS did not include any
information in the food superstore sub-category for developments of similar size.
© Association for European Transport and contributors 2008
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However, developments categorised by TRICS under retail parks - including food
have similar gross floor areas. Assuming this category, TRICS underestimated
the peak hour trip rates for both shopping centres.
For stand-alone food superstores, TRICS did not include this sub-category for
developments of similar size to SuperValu, Ballincollig. However, developments
categorised by TRICS under discount food stores have similar sizes to
SuperValu, Ballincollig. Assuming the discount food stores category, TRICS
predicts a total evening peak hour trip rate of 6.96 vehicle trips/100m2 for an
average gross floor area similar to SuperValu, Ballincollig. This underestimates
the measured evening peak hour trip rate by 13.70 trips/100m2, which is
substantial.
For equivalent size discount food stores, the evening peak hour trip rate
predicted by TRICS substantially underestimated the measured trip rates.
In summary:
•
For food superstores with non-food sections using TRICS overestimated
the evening peak hour trip rates.
•
For food superstores which are part of larger shopping centres, the
predicted TRICS rates were less than the measured trip rates.
•
For stand alone food superstores and discount food stores, the measured
trip rates were considerably greater than the trip rates predicted using
TRICS.
The differences between the measured trip rates and those predicted using
TRICS could be partly because TRICS did not have exact equivalent categories
to the retail food superstores studied in the Cork region.
5.2 Comparison between Measured and Predicted Trip Rates for Office
Blocks
Table 7 shows the predicted TRICS trip rates and the measured trip rates for
office blocks. From this table it can be seen that TRICS overpredicted the
morning peak hour (8.00-9.00) trip rates for three of the Cork office blocks and
underpredicted the other. However, these differences are reduced when the trip
rates from 7.30 – 8.00 are taken into account.
The evening peak hour trip rates using TRICS were similar to the trip rates at the
two office blocks where evening peak hour counts were taken.
© Association for European Transport and contributors 2008
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Table 7. Predicted and measured peak hour trip rates for office blocks
Name
Time
Trip rates (light vehicles per 100m2 GFA)
IN
OUT
TOTAL
Jacobs
7.30-8.00
Observed 1.08
0.08
1.16
Engineering,
TRICS
0.35
0.06
0.41
Mahon, Cork
8.00-9.00
Observed 1.49
0.09
1.58
TRICS
1.94
0.21
2.15
17.00-18.00 Observed 0.15
1.53
1.68
TRICS
0.24
1.53
1.77
8.00-9.00
University
Observed 1.45
0.12
1.57
Technology
TRICS
1.46
0.25
1.71
Centre
RPS-MCOS,
7.30-8.00
Observed
0.78
Ballincollig,
TRICS
0.35
0.06
0.41
Cork
8.00-9.00
Observed 3.33
0.14
3.47
TRICS
1.94
0.21
2.15
17.00-18.00 Observed 0.07
1.56
1.63
TRICS
0.24
1.53
1.77
Cork Airport
8.00-9.00
Observed 1.63
0.10
1.73
Business Park
TRICS
1.82
0.18
2.00
5.3 Comparison between Measured and Predicted Trip Rates for
Residential Developments
Table 4 showed the measured total morning peak hour trip rates for residential
developments in the Cork region. The total morning peak hour trip rates varied
from 0.27 cars trips/household to 1.65 car trips /household. Median trip rates for
Inner City, Suburban, Rural and County Town developments were shown in
Table 5. Table 8 compares these median trip rates with the equivalent predicted
values using TRICS.
Table 8 Predicted and measured total morning peak hour (8.00-9.00) car trip
rates by location
Location
Median total car
Range
TRICS total car trip
trip rate/ household
rate / household
Inner city /
0.53
0.27 – 0.94 Privately owned: 0.11
town
Rented: 0.08
Suburbs of
0.94
0.89 – 1.11 0.62
Cork City
Rural areas
1.11
1.00 – 1.27 0.70
County towns 0.69
0.42 – 1.65 0.70
The TRICS predicted trip rates are substantially lower than the measured trip
rates for than the measured trip rates for inner city, suburban and rural residential
developments.
© Association for European Transport and contributors 2008
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6. DISCUSSION
The traffic impact of a proposed development depends on the type and size of
the development, on its location and on the receiving road network. As previously
indicated, the impact of a specified amount of vehicular traffic on the road
network can be quantified within an acceptable level of accuracy using
established United Kingdom junction and network traffic models.
6.1 Retail Food Superstore Trip Generation Case Studies
Peak hour trip rates were measured for two food superstores with non-food
sections, two food superstores which are part of larger shopping centres, one
stand-alone food store and two discount food stores. These developments were
all located in the Cork City region. The measured trip rates indicated that the
peak hour trip rates varied by the type of food store but were consistent for each
type of food superstore. The evening peak hour trip rates for the stand-alone
food superstore and the discount food stores were substantially higher than for
the other types of food superstore studied.
The measured peak hour trip rates for retail food superstores did not compare
well with the rates predicted using the TRICS database. It is suggested that this
may be because TRICS does not include a sufficiently detailed breakdown of the
different types of food store (the retail food superstore categories in TRICS were
not directly comparable with the food superstores studied). Also, TRICS does not
include whether there are similar developments in the vicinity.
Consequently, it is suggested that the traffic from a proposed retail food
superstore can only be accurately estimated by comparison with existing
developments in similar locations and distances from competitive developments.
6.2 Office Block Trip Generation Case Studies
The morning peak hour trip rates were expressed in terms of trips per 100m2
gross floor area rather than per number of employees which was not considered
a suitable parameter.
Based on the limited studies of office blocks in the Cork City region, it is
suggested that the size of an office block has little influence on the morning and
evening peak hour trip rates per 100m2. However, the operating hours of offices
appeared to have a significant influence. At present TRICS does not include
information on office operating hours.
The trip rates predicted by using TRICS were fairly similar to the trip rates
measured during the case studies. Thus it is considered that the TRICS
database reasonably represents the trips generated by offices.
© Association for European Transport and contributors 2008
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6.3 Residential Trip Generation Case Studies
The residential development case studies indicate that the location of a
development has a significant impact on the morning peak hour trip rate.
The morning peak hour car trip rates predicted by using the TRICS database
were significantly lower than the measured rates. This may partly result from
lower public transport use in Ireland than in the UK. To predict accurate
residential morning peak hour trip rates, the location relative to the city centre
should first be identified (Inner City, Suburban, Rural, County Town).
Developments in similar locations should then be used to estimate the morning
peak hour trip rates.
7. CONCLUSION
This paper investigates the traffic impact assessment of developments in Ireland.
Trip rates from existing developments were measured mainly in Cork City and
County Cork. Conclusions include that the traffic impacts of a proposed
development depend primarily on the number of trips generated and that there
was a wide range of trip rates for the developments studied. Also, that existing
methods for estimating trip generation were not accurate for certain types of
development.
In Ireland, the TRICS database is typically used for trip rate calculation when
applying for planning permission. Reduced trip rates are then assumed where
new public transport services or mobility management plans are proposed.
TRICS was found to give reasonably accurate trip rates for office developments
but was not considered appropriate for retail food superstores or for residential
developments. This suggests that the impacts of the latter developments require
extra attention and should not rely solely on the TRICS database.
Traffic impact assessments depend directly on the assumptions made about
developments. These assumptions are often biased since those seeking
planning permission tend to make favourable assumptions. Post development
traffic impact assessments are required to verify the accuracy of the process.
Bibliography
Grealy, R. (2006). Traffic impacts of developments. MEngSc thesis. University
College Cork.
O’Cinneide, D and B. O’Mahony (2005). The evaluation of traffic microsimulation
modelling. Urban Transport XI. Urban Transport and the Environment in the 21st
Century, WIT Press Southampton.
TRICS www.trics.org.
© Association for European Transport and contributors 2008
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