Welcome to the Roadway Centerline wiki page! This is an exhaustive 'deep-dive' of the inner workings of the DDOT GIS team's main reason for existence: the centerline.
We maintain centerline-based roadway data for all roads and alleys open to traffic within the District of Columbia. DDOT uses a linear referencing system (or LRS) to maintain both the centerline/road GIS as well as the various attributes and characteristics about that roadway. There are 3 major components of our LRS-based centerline GIS:
From these 3 components, we derive a multitude of other data and products for many uses. Some of the more popular ones are:
In the years since it's inception, the simple centerline has changed quite a lot. Read a bit more about the origins of the DDOT centerline: from paper-based engineering drawings and ROW cards in the DC Office of the Survey all the way to our modern-day LRS. We've come a long way and it's interesting to understand where we've been. Visit the DDOT Centerline Legacy page for more.