No Traffic Flow Study Available: Demanding Answers with Traffic Flow Analysis

Traffic Flow Analysis Formulas: Understanding the Complexity Behind the Roundabout Proposal

Let's define the traffic flow variables for each street:

  • Drakes Creek Road (Main Road)
    • EDC: Number of vehicles entering the roundabout from Drakes Creek Road.
    • XDC: Number of vehicles exiting the roundabout onto Drakes Creek Road.
    • FDC: Total traffic flow passing through the roundabout along Drakes Creek Road.
  • Anderson Road
    • EAN: Number of vehicles entering the roundabout from Anderson Road.
    • XAN: Number of vehicles exiting the roundabout onto Anderson Road.
    • FAN: Total traffic flow passing through the roundabout from Anderson Road.
  • Avant Lane
    • EAV: Number of vehicles entering the roundabout from Avant Lane.
    • XAV: Number of vehicles exiting the roundabout onto Avant Lane.
    • FAV: Total traffic flow passing through the roundabout from Avant Lane.
  • Countryside Drive
    • ECS: Number of vehicles entering the roundabout from Countryside Drive.
    • XCS: Number of vehicles exiting the roundabout onto Countryside Drive.
    • FCS: Total traffic flow passing through the roundabout from Countryside Drive.

Traffic Flow at Each Entry/Exit Point

To calculate the total traffic flow passing a given point, you must combine vehicles entering, exiting, and passing through the roundabout from other points:

1. Traffic Flow on Drakes Creek Road:

FDC = EDC + (EAN × PAN,DC) + (EAV × PAV,DC) + (ECS × PCS,DC) - XDC

Explanation: The total flow on Drakes Creek Road includes vehicles entering from Drakes Creek itself, plus vehicles entering from other streets (Anderson Road, Avant Lane, Countryside Drive) that pass through to exit on Drakes Creek Road. Subtract the vehicles that exit at Drakes Creek.

2. Traffic Flow on Anderson Road:

FAN = EAN + (EDC × PDC,AN) + (EAV × PAV,AN) + (ECS × PCS,AN) - XAN

Explanation: The total flow on Anderson Road consists of vehicles entering from Anderson itself, plus vehicles entering from other streets and passing through to exit on Anderson Road, minus vehicles exiting at Anderson.

3. Traffic Flow on Avant Lane:

FAV = EAV + (EDC × PDC,AV) + (EAN × PAN,AV) + (ECS × PCS,AV) - XAV

Explanation: The total flow on Avant Lane includes vehicles entering from Avant Lane, plus those passing through from other streets and exiting at Avant Lane, minus vehicles exiting at Avant Lane.

4. Traffic Flow on Countryside Drive:

FCS = ECS + (EDC × PDC,CS) + (EAN × PAN,CS) + (EAV × PAV,CS) - XCS

Explanation: The total flow on Countryside Drive accounts for vehicles entering from Countryside, plus those entering from other streets and passing through to exit at Countryside, minus vehicles exiting at Countryside.

Proportions of Traffic Between Points

Define the proportions of vehicles turning between entry and exit points:

  • PDC,AN: Proportion of vehicles entering from Drakes Creek Road that exit onto Anderson Road.
  • PAN,DC: Proportion of vehicles entering from Anderson Road that exit onto Drakes Creek Road.
  • PAV,CS: Proportion of vehicles entering from Avant Lane that exit onto Countryside Drive.
  • And so on… for all combinations of entry and exit points.

Total Traffic Passing Through the Roundabout

TTotal = FDC + FAN + FAV + FCS

Conclusion

Where is the data to justify this project and demonstrate its necessity? We need concrete evidence showing that this roundabout is essential for improving traffic flow and safety rather than simply being a project driven by other interests or political motives.