The Arca T-junction is a meeting point of three roads: Martadireja I Road
to the West, Martadireja II Road to the South, and Senopati Road to the North. The
study aimed to determine the capacity and degree of saturation at the Arca Tjunction
in Purwokerto. The research method involved conducting traffic volume
surveys and analyzing the feasibility of signalized T-junction performance based
on the Indonesian Road Capacity Manual (MKJI) 1997. From the calculation
results, the capacity of each network of the Arca T-junction is as follows: 810
pcu/hour for the North of Senopati Road, 317.7 pcu/hour for the South network,
and 448 pcu/hour for the West network of Martadireja Road. The degree of
saturation (DS) at the Arca Intersection was greater than 0.75, specifically for
Senopati Road with a DS of 1.164, Martadireja I Road with a DS of 1.39, and
Martadireja II Road with a DS of 1.312. It indicated the service level based on the
Q/C ratio. A Q/C ratio of 1.00 corresponded to a service level (F), categorizing
heavy traffic flow, low speeds, long queues, and significant congestion or delays.