Traffic Survey

There are many reasons for the changes in traffic flow during a day, the obvious one being “rush hour” travel to and from work. Traffic jams and congestion can occur from time to time, perhaps due to a lorry unloading or a special event that is taking place.

A traffic survey is one of several included in this survey spreadsheet.

Activity

List 8 -10 different reasons why traffic may become congested in Ironbridge.

If you drew a “Prediction Graph” showing the traffic flow in Ironbridge over 24 hours what would it look like hour by hour. Draw your own graph using Excel, for each hour, using the data and labels below. (you can use a label more than once and even add extra ones)

Imagine that the highest no of vehicles passing in one hour was 500.
Imagine when deliveries may take place to shops.
Imagine that besides cars there were also other types of vehicles.

Labels

No traffic.
Wet morning
Sunny afternoon
Traffic congestion.
People travelling to work.
People returning home from work.
Light traffic flow.
Large number of tourists.
Very heavy traffic.
Local people shopping.
Traffic increasing.
Traffic decreasing.
Lunch hour traffic.
Evening traffic to local pubs and restaurants.
Peak traffic flow.

Using the Census sheet below, or one similar, carry out your own traffic survey and compare it with your own “Prediction Graph”.

This activity will certainly be done as a group.

You will need to make sure you are at your CORRECT SURVEY POINT. Check and record if you are recording IN or OUT traffic.

On this sheet you are recording in 5 minute blocks for 30 minutes .You may be asked to record for less time.

Remember it is a team effort and you should stick to the time set or the results will not be accurate and RELIABLE.

Complete your TALLY (count) like this //// = 5. //// // =7.

VEHICLE MOBILITY UNITS –VMU’s

This is a simple way of estimating if a road is wide enough for the AMOUNT of traffic and the TYPE of traffic flowing along it. Each type of vehicle is given a value based on it’s manoeuvrability and the space it takes up on the road.

Vehicle Type	Worth
Cycles	1
Motorcycles	1
Cars and Taxis	2
Vans and Minibuses	3
Buses and Coaches	6
Lorries	6
Articulated Lorries	8

What to do

1 Count the number of vehicles pasing your survey point.

2 Each type of vehicle is worth a different score.

3 Calculate and add up the total number of point.

4 This represents a VMU score.

5 You need a VMU score for 1 hour (if you recorded for only 30 min. multiply your score by 2. If you score is only for 15 min then multiply by 4)

You now need to see if your road is too narrow for the amount of traffic recorded.

6 Use the details below to find out if CONGESTION is likely to happen and there could be angry motorists and traffic jams.

TYPE OF ROAD VMU TOTAL PER HOUR

Narrow single lane road with passing places 200

Two lane road but with Kerbside parking or

Unloading bays or Traffic calming 400

Ordinary two lane road 750

Three lane road 1500

Dual carriageway (2 lanes each side) 3000

Motorway (3 lanes each way) 6000

EXTRA Activity

7 Try to produce flow diagrams of some of your results.

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