Unit G2 - Fieldwork Exercise

The CBD of Birmingham

Summary of Tasks

The study site was an 8km squared area of Birmingham's city centre where an investigation of Sphere of Influence and Pedestrian Flows was undertaken.


Our fieldwork in the CBD of Birmingham focused on the retail, commerce and entertainment zones. The area has been subject to urabn renewal and attracts 24 million of visitors each year.

The aim of this investigation was to:


1. Determine the Sphere of Influence of Birmingham's CBD. Divided up into sectors we aimed to gather information via questionnaires and;

2. Calculate the Pedestrian Flows.


We used appropriate land use maps and we targetted a 'normal' working day. The middle of the day was the target time as the pedestrian flow would have reached a peak, resulting in, hopefully, more people being present, culminating in more reliable, accurate results and responses.


Data Collection

The 8km squared central retailing, commerce and entertainment zone of Birmingham's CBD was sub-divided into 7 sectors.


1. Questionnaires - the target for all the 7 sectors was a total of at least 70. This was worked out of the basis of a 1 in 4 hit rate with people willing to response sensibly. Click here to view a copy of one of the questionnaires.


2. Pedestrian Flows - data was collected over one day and included; pedestrain flow count over 2 minutes at a set point, undertaken every 30 minutes.



We did random sampling because we wanted to get a representative sample of the CBD of Birmingham. The random sampling strategy worked because it covered a large area and had a large sampling frame. Strengths of the sampling were that we covered the whole of the area which was 8km squared in total. This area was split into 1.5km squared sectors each so they were manageable for people to survey. A weakness of the sector technique was that the sectors were large and people had a different number and variety of places and streets to survey. Another weakness was that for some it was hard to cover all areas.






(i) Age and Gender - also displayed as pie charts - this showed mainly 'younger' pedestrians in all sectors

(ii) Travel time - most travelled less than 30 minutes

(iii) Purpose for visit - bar chart - showed - modal group were 'workers' followed by 'shoppers' - however if this was undertaken on a Saturday the modal group would have shifted to 'shoppers' - needs further investigation.

(iv) Mode of Transport - displayed in a pie chart

(v) Accessibility - bar charts - this generally showed that Birmingham's CBD was clearly accessiblity by public transport as the majority of those questioned had come by either bus or train.


Desire Lines were drawn for the Sphere of Influence. In the past it would have been possible to do a 'Reilly's Break-Point Analysis' based on population sizes of the neighbouring larger urban centres, however this technique is viewed as inappropriate in the 21st century, where travel is now a function of time instead of absolute distance.


Isoline Maps showing pedestrian flow patterns.




1. We concluded the Sphere of Influence was up to 40km or 1 hour's travel time. This accounted for 98% of visitors.

2. On a weekday, the largest number of visitors were workers to the CBD and the second largest were shoppers.

3. Tourist represented only 10% of visitors in March.

4. Gender - this was equal in numbers, however 80% appeared to be under the age of 50 years.

5. The greatest number of visitors came by bus 40% with  train 30% car 25% cycled 5%

6. Pedestrian Flow - this clearly showed the peak flow to be around the Bullring on Thursday - and on Friday the Market Zone.




This was an excellent sample area (representative at 8km squared) with a large number of pedestrians willing to give meaningful, helpful responses.

As a result of the responses of the questionnaires being positive and detailed they could be taken as both valid and reliable often without bias.


Strengths included the fact that many found visitors willing to answer questions - this was the opposite to what was expected  - it is believed that the younger age of the interviewers was less threatening to the public in general and made them more willing to stop and be helpful.          


Weaknesses: There were however some inconsistencies with the questions asked by different groups - especially those sampling on different days of the week. Again on the questionnaire some of the categories in terms of journey time were quite crude and could have been more detailed. In addition the 'mode of transport' categories were rather limiting - in that some people had accessed the CBD via both train and bus and the questionnaire had not considered this possible response.