"The"is not necessary in that sentence or context. Here are some examples taken directly from my city's website today:
For months, construction on busy Texas 26 in Colleyville has slowed traffic.
We spent a lot of time in our car, stuck in traffic.
All lanes of Interstate 35E in Carrollton reopened to traffic Wednesday afternoon.
The massive 16-lane highway travels through Bedford, Euless, Fort Worth, Irving and Dallas and will hopefully bring some traffic relief.
Traffic is being forced onto the frontage roads as crews demolish the Abram Street exit.
A 5 car pileup has caused traffic to slow and has created a 5 mile backup.