It's time to create the "Port Authority" of Montgomery and Prince George's Counties
1. Otherwise the Purple Line transit line may never get built.
Probably the only way to build the line, given how the State of Maryland's transportation priorities are focused on the Inter County Connector, HOT lanes on I-95 north of Baltimore, and maybe Baltimore, not to mention dealing with the infrastructure ramifications of military base expansion in the Fort Meade area due to the BRAC process, is to create an "urban renewal district" that can sell bonds with repayments based on the anticipated gain in property and other tax revenues.
Note that I am not so familiar with the proposed route that I have a sense about how much new value will be created. One of the problems is that it takes quite a while for the new value to kick in, at least 12-15 years...
The Interstate, or Yellow, Line in Portland, Oregon was built using such a method.
And of course, the Port Authority of New York and New Jersey funds projects that benefits both states, such as transportation projects like the PATH subway trains.
Closer to home, the Gateway Georgia Avenue Revitalization Corporation operates in both Silver Spring, Maryland and in the Upper Georgia Avenue section of DC.
2. And efforts in Takoma Park to improve New Hampshire Avenue and University Boulevard will be harder to pull off without the creation of a bi-county authority. This is because one side of New Hampshire Avenue is in MoCo, the other in PG, and in different parts of the corridor, value capture varies by county, based on the opportunities presented. But to pay for it all, you need the tax increment revenue increases from both sides of the street.
Note that the Port Authority of New York and New Jersey gets no taxes, only revenues from operations and fees such as the airports, etc., and a bi-county authority in Montgomery and Prince George's Counties couldn't operate in the same way.
Nonetheless, a local authority in those two counties would be a logical extension of the legally combined, but in reality separated, bi-county Maryland-National Capital Park and Planning Commission, which is supposed to manage planning in those two counties in ways that are complementary to the federal presence in the District of Columbia. (Each county has its own planning operation and procedures.)