If you can't get water out of any faucet through both the dockside water and the on board system, then it's likely the screens in the faucets need to be cleaned. Having said that, you may also have an issue with other hardware items the guys have mentioned above; fresh water pump, clogged strainer, faulty dockside inlet, etc.
Remove the screen from one of the faucets and turn on the dockside water, if you don't get anything, it's likely your dockside inlet assembly. They don't last forever and if the boat get winterized, it may not have been done properly which is a common occurrence. To check the on board system, ensure there is water in the tank and remove the inlet to the pump. You should get water coming out of the hose. If you do, hook back up, remove the outlet hose and turn the pump on. If you don't get water, it's a faulty pump. If you get water, it's either your faucet screens or mixing valves in the faucets themselves. These can be clogged with debris from the tank or dockside water supply. If you use a powdered cleansing product in the tank, this can contribute to clogging. I have found that not all the products on the market dissolve completely. For that reason I only use liquid cleansers now.
Camco makes a good product. This stuff will remove pink residue from winterizing left in your water lines that you thought you rinsed out during commissioning:
https://www.amazon.com/Camco-40207-TastePURE-Cleaner-Deodorizer/dp/B000EDUTQSStarbrite also has a product. I find it to be more expensive but I haven't found that it works any better:
http://www.starbrite.com/item/aqua-clean-water-tank-flush