Practice "Plus-One Boating" by bringing back everything you take out on your trip—plus one piece of litter from someone else's wasteful wake. Make sure to bring all food containers, cigarette butts, and other trash back to shore and use the marina’s garbage or recycling facilities to dispose of it. More than an eyesore, trash in the water impacts the health of humans, wildlife, ecosystems, and economies.

• If a piece of trash blows into the water, retrieve it immediately. Seize the opportunity to practice “man overboard” drills by calling “Trash overboard!” Leave trash in the water, and an animal that mistakes it for food can choke or experience a false sense of fullness and starve.
• Remind others that it is illegal to discard plastic trash into the water, and encourage them to bring it back to shore for recycling. Birds, fish, and other animals that become entangled in debris such as fishing line can’t properly swim, feed, or mate, and may drown. Additionally, boaters can face expensive repairs when marine debris entangles a propeller, clogs an engine, or scars a hull.
• Report any dumping you witness to the US Coast Guard Marine Safety Office. Many kinds of trash can leach toxic chemicals, and cleanup costs taxpayers and business owners millions of dollars.

Use the appropriate ground tackle for the type of bottom (sand, mud, or rock), and always check your charts or use a depth finder to locate appropriate holding grounds.

Underwater damage caused by a single anchor might seem small, but the cumulative effects of many individuals add up to serious long-term damage. Aquatic grass, a nursery habitat for young fish, seldom re-grows in exposed sandy areas, and coral damage often invites disease.

• Use existing mooring buoys as much as possible, but DO NOT attempt to motor across a shallow reef to reach one.
• Lower the anchor gently. If you hear a grumbling noise, indicating you have hit a reef or rocky substrate, move to another spot.
• Communicate with other boaters in the area. Let them know if you find an appropriate anchorage, or hail nearby boaters if you need assistance finding a safe anchoring bed or set mooring.

Of course, you should try to avoid running aground, but accidents happen. If you run aground in a small boat, use a paddle or an oar to pole your way out from the same direction the boat entered. If in a larger vessel, radio, call, or hail for assistance or a tow.

Navigating a vessel through shallow waters can cause significant environmental damage. As boats travel into shallow water, their propellers may cut into aquatic grass beds, often trenching the bottom and removing all grass blades and even sediment. This is particularly true of personal watercraft that use powerful water jet propulsion systems. Natural recovery of damaged grasses takes from three to ten years.

• Consult an official and up-to-date nautical chart.
• Follow channel markers and heed buoy warnings.
• Use the depth sounder.
• Pay attention to the water patterns. Shoals and shallow areas can be detected early on if you pay attention to the surface water around your vessel.
• Always wear your life jacket while on board and have Personal Flotation Devices (PFDs) readily available in an emergency.

As a rule, boaters should always slow their boat when approaching an aquatic animal. States differ in their local laws, but it is always illegal under federal law to feed, harass, molest or injure aquatic mammals such as whales, dolphins, manatees, or sea otters. Any activity that forces a protected or endangered animal to change its behavior is considered harassment.

• When observing an aquatic animal, maintain a safe distance of 100 yards (500 yards for the highly endangered northern right whale). Always check local regulations, which could be stricter.
• Maintain a safe speed at all times to prevent harm to yourself or wildlife. Traveling at high speeds impairs a boater’s ability to see sandbars, submerged obstacles, dangerous shoals, or animals in the water, which could lead to serious accidents. Additionally, excessive wake in sensitive areas can damage shorelines and nearshore habitats.

Many invasive species epidemics begin with the update and discharge of ballast water from ships. Recreational boaters can also spread exotic species when boats or equipment are moved from one body of water to another or when unused bait is dumped into the water.

Invasive species may have no natural predators in a new environment, leaving them free to reproduce unchecked. In addition, they can alter the ecosystem by preying voraciously on native marine life. They can also have significant economic impacts: the zebra mussel, which can clog pipes, cost the Great Lakes region alone about $5 billion in nuisance control in 2000.

• When leaving the water, inspect your boat and remove all hitchhiking animal and plant life from the hull, trailer, propeller, intake areas, and all equipment. Also drain and flush engine cooling system, live wells, bilge, and bait buckets with very hot water if possible. If hot water is not available, use tap water.
• Rinse your boat and all areas that get wet with tap water. Make sure to include trailer frames and wheels, safety light compartments, decking, and the lower portion of the motor cooling system. DO NOT use salt and/or chlorine water mixtures. Runoff of these mixtures could enter the waterway, where they would be harmful to native aquatic organisms. Also, these mixtures can damage boat equipment.
• Air-dry your boat and other equipment three to five days before using in a new water body. Some invasive species, like the zebra mussel, can live for at least 48 hours out of water.
• DO NOT dump unused bait or its packing material into the water. While bait may be bought locally, it is often shipped from farther away. People fishing aboard boats may discard live bait fish without realizing these can become dangerous invaders.

Discharge of raw sewage from a vessel within three nautical miles of the US coastline and Great Lakes is illegal. By keeping onboard toilets in line with sanitation laws, you can prevent potential disease-causing pathogens from infecting swimmers and shellfish.

Think one boat doesn’t make a difference? A single overboard discharge of human waste in a bay or other enclosed area can be detected across a whole square mile.

• Use a Marine Sanitation Device (MSD) as required by law to keep sewage and chemicals out of the water. Human waste contains nutrients that can stimulate algae growth, depleting the amount of oxygen in the water. This process, called eutrophication, leads to foul odors and harms and can result in harm to aquatic life, such as mass fish kills.
• Close any direct flow-through system when navigating within three nautical miles of the US coastline or in a “no-discharge” zone. If your MSD is equipped with a Y-valve, the valve should be closed or set in the inboard positions.
• Bring portable toilets ashore for proper disposal of sewage. Pathogenic contaminants such as streptococci, fecal coliform, and other bacteria may cause infectious hepatitis, diarrhea, bacillary dysentery, skin rashes, and even typhoid and cholera.

Sea grass beds provide food, shelter, and nursery grounds for all kinds of marine life, from sea turtles and snapper to the microscopic plankton that sustains them. You might think that a propeller cutting the grass blades is no big deal, but boaters should understand the complex root system of these plants, and how a slip of the propellor can actually inflict significant harm that creates a domino effect for sea life.

Sea grass root systems are based on interconnected rhizomes, which send shoots out in all directions. New plants grow upward from those shoots. When a boat cuts a path through those rhizomes, the grass bed is essentially divided in half. The channel cut by the boat causes water to flow faster through the grass bed, promoting further division and destruction of the bed.

First, that new canal exposes sediment. Grasses can be finicky; many are sensitive to increased water flow because suspended sediment blocks sunlight needed for photosynthesis. Additionally, some grasses simply cannot survive in areas of fast-moving water. When a grass bed is damaged or dies, the impacts ripple out through the food web, affecting a wide range of living things that depend on it. So boat carefully in the presence of this precious habitat.