In addition to these reasons, there are a few other items to add in terms of the geography of the current line and a few logistical concerns. Below are a few reasons:
- A new line somewhere else would require more overhead. If a new line is to be built anywhere else that doesn't connect to the existing line (for example along 56th), a new maintenance base and new vehicles, etc will all be needed. Basically more overhead will be needed whereas extending the existing system will be able to use and build upon the facilities that already exist.
- Extending the existing line south would be hard. This is because of WSDOT's I-5 M St to Portland Ave HOV Project. In this project, I-5 will eventually undergo a major upgrade which includes the demolition and reconstruction of the Pacific, McKinley and L St bridges, not to mention most of I-5 itself.
- Could Tacoma Link climb steep hills? While I don't know for sure if the streetcars can climb such a grade, it would seem difficult to extend the streetcar up a road like 13th or 11th or even 9th due to steep hills.
- Going northbound is easy. Stadium way is truly the most logical street to extend the existing system since the tracks end just before it. Stadium Way needs replacing anyways and according to the City of Tacoma's Six-Year Comprehensive Transportation Program (pdf) it is already funded to be replaced, only without the streetcar tracks (but apparently with a track-friendly design).