Boating on Rivers, in Shallow Waters, and in Heavy Seas …

Boating on Rivers, in Shallow Waters, and in Heavy Seas … An estuary is a partially enclosed body of water with one or more rivers or streams flowing into to it, and with free connection to the open sea. You might be surprised to learn that the Long Island Sound is an Estuary. It is fed by the fresh waters of the Hudson, the Housatonic, the Connecticut, and the Thames rivers. On the South Shore, a network of interconnected bays, rivers, streams and wetlands create an estuary between the mainland and the barrier islands such as Long Beach and Jones Beach … Operating the Helm on Rivers and in Shallow Waters … Shallow water has a considerable effect on the maneuverability of boats large and small. This is because a limited depth of water changes the pressure around the boat’s hull … Reading Currents … A 1-knot current causes ripples on the surface. A 3-knot current causes swirls and eddies for several yard. A 5-knot current causes a V-shaped boiling wake for up to 50 yards downstream … Bends in Rivers and Channels … The deepest water is found on the outside of a bend in a river. Experienced Skippers know this and steer the ship to toward the outside of the bend. This current driven depth effect is also present in channels. So, keep an eye on the surface conditions in shallow waters, and stay within the outer side of the channels marked with red and green buoys … Shallow Water Forces … When a ship moves through a channel in shallow waters, it is impacted by three important forces that many recreational boaters are not aware of. These forces have a significant, and they have a negative impact on the maneuverability on the ship. These forces are named Squatting, Bank Cushion, and Bank Suction … Squatting… This is especially dangerous in shallow waters. It occurs as the boat is accelerating. At the same time, the stern will be drawn closer to the bottom because the engines are creating a vacuum beneath the stern by pushing the water out from under the boat. The result is the boat’s stern gets sucked down and repositioned closer to the bottom. This is dangerous because the propellers are drawn closer to the bottom where they can be damaged by rocks, gravel and sand … Bank Cushion … This force is created by the bow wave pushing against the bank. This bow force then pushes the bow away from the bank. To regain control the helmsman needs to correct the ship’s heading … Bank Suction …This force pulls the stern towards the bank. When combined Bank Cushion and Bank Suction have a significant impact on the boat’s heading. To manage the impacts of Bow Cushion and Bank Suction remember that slow and steady wins the race … Helmsmanship in Fowl Weather Conditions … When the weather is bad and the seas are high it is best to heave to and take the seas “fine to the bow”. This means take the sea directly into the wave so that the bow’s flare can push the water to each side, and avoid running over the waves. It is also advisable to slow down while the flare of the ship’s bow is gently pushing against the waves. This maneuver will moderate pounding and prevent the boat from broaching or pitchpoling … Broaching … This occurs when the force of the wave has pushed your boat parallel to the face of the wave. If this happens to you, quickly increase the throttle while aggressively turning into the face of the wave. If this is not successful the boat is in danger of being capsized. …Pitchpoling … If you find yourself in very rough seas it is possible for a large wave to flip your boat end over end. The best way to prevent this is to respect the power of the seas and not venture out when severe storm warnings are announced … Rough Inlets … My advice is to pick your days and don’t be a show off … Unexpected Heavy Weather … When you are out to sea weather conditions can change quickly! When this occurs, experienced Skippers head back to port. If you are faced with having to return through an inbound sea in an Inlet with inbound breakers, heave to, and wait for conditions to subside. If heaving to is not an option, position your boat so that you are heading home between the waves before they start to break. Stay in the trough as long as you can while making sure the wave behind is not overtaking. As you continue through the inlet stay in the trough, but do your best to stay on the lower back end of the wave in front. Once there wait for the wave to crest and break ahead. Once the break is completed increase your speed to power through the white water ahead … Other Motions Encountered on the Water … Yawing … This is produced by a quartering sea that causes the boat to move from side to side. Sometimes this can be prevented by increasing speed. A drogue (also known as a storm drogue) is a device trailed behind a boat on a long line attached to the stern. A drogue is used to slow the boat down in a storm and to prevent the hull from becoming side-on to the waves … Heave … This is the vertical motion of a vessel that is lifted by the motion of the sea … Rolling … Vertical motion of a boat from the bow to the stern … Surge … The forward and aft motion of a vessel.