The bilge of a boat collects the water from small leaks on the hull and from the inside of the boat. The water collects on the bottom of the hull, where on larger boats, it is pumped out, and on smaller boats it remains until the boat is landed and drain plugs are removed to empty the bilge water
Tools & Technique
To clean the bilge of your boat, use a strong formula of trisodium-phosphate. Remove drain plugs and pour in the solution. On smaller boats rock the boats to allow the TSP solution to run up the hull as far as the bilge water would have reached. On larger boats that can not be rocked, replace drain plug and launch boat as normal, and drain the next time the craft is dry docked. Rinse the bilge with fresh water if possible.