Virginia Watercraft Owner's Guide
Towing Another Boat
Special care is required for towing because the towline can get tangled around the propeller shaft of the towboat. Poly line is good because it floats. At night, shine a spotlight on the towline to reduce the chance of another boat hitting it.
Motorboats underway in conditions of reduced visibility, towing or pushing, give one prolonged horn or whistle blast followed by two short blasts every two minutes. The towed vessel immediately follows the towboat sound signal with one prolonged blast followed by three short blasts.