Sending money back from Washington to pay for important local projects is not really the problem.
Pork projects, or earmarks as they seem to be called now, amount to about 3% of the Federal Budget (correction welcome if that figure is wrong).
The big problem is that they are never discussed or debated for merit. They are tucked in Defense appropriation bills or other legislation that is absolutely unrelated so that we cannot shine the light of day on them. Thus many are blatant pay-offs to special interest groups or political contributors. That was once called corruption.
We sometimes hear about them later, such as the "bridge to nowhere", but there might not be such a thing if the earmark required open discussion in Congress. John Boehner has made that a priority and he will be treated rudely if he does not keep his word.