:: plumbing expert? help! ::

relevant searches are getting me no where this morning & i'm hoping someone will magically post a solution on my site by the end of tonight, otherwise my dad is going to be getting a phone call (it's too early right now!).

the problem is my pipes. with all the construction going on at home, i've noticed when they use our hose outside that there is a constant whining sound from within the house. and now i am hearing that whining for a few seconds after i shut off the tap (after it has run for a few seconds) or flush the toilet--upstairs or downstairs doesn't seem to matter.

any ideas/thoughts?