On top of roadkill itself, there's a reasonable (IMO) argument to be made that car-centric development is a big source of our looming water problems: the US has drained or redeveloped astounding amounts of natural swamp, marsh, and wetlands to make space for car-dependent living patterns. That means less water percolating into already over-stressed aquifers. It's a trite thing to say, but our grandchildren are going…
This is most definitely the case. It has also caused enormous problems for places where flooding was already a threat, by removing the natural buffering capabilities that places like wetlands have. In fact, a whole field (stormwater engineering) exists to mitigate this.
:)