This one is my B.S. Graduation Project that I did at Bogazici University. For this one, me and my team worked with Prof. Ilgin Gokasar (who I was already working for as a research assistant) to propose a number of different solutions for Yildizcicegi Alley, and Nispetiye Street which Yildizcicegi blocks.
This image is a common view of Nispetiye, and the oncoming traffic from the left hand side is Yildizcicegi Alley. People uses this alley to pass over to Ulus district, which is to the right hand side of the picture. However, as there is no signalization on the intersection, and also the aggressiveness of Turkish drivers, grid-lock is experienced.
We have proposed several solutions, and investigated their benefit-cost ratios, using microscopic simulation to get the travel times, GHG emissions and fuel savings, comparing them with infrastructure investment costs. The solutions are,
- Tunnel under Nispetiye Street, creating an uninterrupted link between Etiler and Ulus
- Double-lane on Nispetiye. Although Nispetiye is actually a double-lane street, the sheer number of parking (as it's a very busy commercial district) reduces this number to one for each direction
- Restructuring the Etiler-Ulus route
- Implementing a signalized intersection
- Implementing a non-signalized roundabout
Here is a screenshot of our control-case PARAMICS network. We tried modeling all the main streets in the area. Detector 1 is located on Yildizcicegi Alley. The main arterial to south is Nispetiye, covered by Zones 1,2 and 3. Ulus is zone 4. The rerouting project uses the northern route to go into Zone 10, which also goes into Ulus.
So what did we find out? The greatest travel time and fuel savings are on Tunnel and Reroute project, however the tunnel project is too costly to undertake. For the reroute, the initial thought was incoming traffic from TEM (one of Istanbul's main freeways connecting the two continents) from Zones 5 and 6 might create a problem. Nevertheless, we discovered that drivers actually do not use these roads for accessing Etiler and Ulus from TEM, making reroute a viable project, which creates around 10 Million USD in travel time, fuel usage and GHG emission benefits without big real investment.
What do I think of this project now that I know more about transportation?
- Although we did different time-of-day counts, we just did them for one day. This is acceptable for a undergraduate project, but not for any professional or graduate level work.
- The point counts we got from ISBAK (One of main traffic consultants for Istanbul) were from 2009. What we did was do our own counts, get a population multiplier and use them. Now, I would do a basic survey around the neighborhood to analyze origin-destination based demands.
If you would like to read the project in detail, you can find it here.
Also, for your entertainment, here is a video of me and my group that we added to our presentation, doing travel time analyses at 5:45 am on Nispetiye Street.
