Want to do something for the environment without having to spend a lot of time and money on it? Then climb aboard – aboard your own boat, that is.

There are literally dozens of ways that you can make your boating greener – and more enjoyable as well – at very little cost.

"You don't have to be a dedicated tree-hugger to make your vessel more environment-friendly," said Susan Shingledecker, director of environmental programs for the BoatUS Foundation. "Most of it is just plain old common sense."

Monitoring the products you use on your boat will keep harmful chemicals from flowing into waterways.Shingledecker's favorite first step is for boat owners to establish a new Captain's Rule on their vessels: "Nothing on this boat goes overboard."

Even apple cores should not be exempt, Shingledecker suggests. "Sure, apple cores and peach pits are biodegradable, but that doesn't mean they're going to disappear overnight," she said. "Besides, it's good practice. Once you get in the habit of not throwing anything over the side, you don't have to think about whether what you're tossing is permissible."

TAKING BASIC STEPS

Bob Miller, a retired college professor who lives in the small boating community of Oriental, North Carolina, says he tries to keep his 28-foot Sabre, Spindrift, as environment-friendly as he can – and generally succeeds, without a lot of time and trouble.

Not only does Miller follow Shingledecker's first rule – he doesn't let his crew toss trash or food overboard – but he powerwashes his boat occasionally to reduce the need for using detergents, and he keeps oil-absorbent pads in his bilge to soak up any excess water or sludge. "When there's water in the bilge," he said, "I sponge it out."

BOB MILLERBob Miller keeps Spindrift environmentally sound with simple, inexpensive measures.Stan Szczyko, a sailboater and powerboater in Bayfield, Wisconsin, funnels the gray water on his boat (the residue from sinks, shower and bilges) into a special recovery tank that he pumps out at the marina when he empties the holding-tank for his marine head.

Both men say they take the extra trouble because they've realized how delicate U.S. coastal and watershed areas have become and they want to help keep them from deteriorating further.

"Pamlico Sound, where I sail, isn't a real open system, so even releasing biodegradable materials into the water can introduce too much nitrogen and phosphate and you get excessive algae," Miller said.

REDUCE, RE-USE, RECYCLE

Running a green vessel comes down to developing good habits when conducting basic maintenance like cleaning, pumping out and fueling. In most cases, taking steps toward cleaner boating is not expensive – and its usually good for the boat, as well as the water around it. Here are some suggestions, culled from organizations including BoatUS, the Coast Guard, the American Boating Association, the California Coastal Commission and the Maryland Department of Natural Resources.

Keep your boat clean. Rinse it with fresh water after every trip, and wash it often, to avoid having to use harsh detergents later to get rid of caked-on dirt and salt. Use mild, biodegradable boat soap, not those that contain toxic ingredients such as chlorine, phosphates and ammonia, which hurt fish. Wax your boat for extra protection. Conserve water by attaching a spray nozzle to your hose. Keep your engine clean to make it easier to spot leaks. Line your bilge with oil-absorbent pads to soak up excess water and oil and replace them when needed, placing used pads in double plastic bags. Do heavy cleaning and maintenance jobs while your boat is out of the water.

Keep your trash to yourself. Limit the amount of packaging material you take aboard, whether it's for tools or food, by stripping off wrappers and other excess while on land. Bring food aboard in reusable containers rather than disposable plastic bags, and take the containers home. Equip your boat with a sturdy trash container with a lid. Stow all loose items, plastic containers and beverage cans properly so they don't blow overboard, and don't let your crew members or guests toss anything into the water. If trash does fall overboard, retrieve it. The Coast Guard sums it up well in its list of tips: "Whatever you take aboard, bring back."

Don't go overboard. Federal law prohibits you from discharging any garbage into lakes, rivers, bays, sounds or coastal waters up to three miles offshore. You may not dump plastic, packing materials or most other trash anywhere from three to 12 miles offshore, and it's illegal to throw plastic over the side in any waters. (If your boat is 26 feet long or larger, you must display this information in a placard, available at most boating supply stores.)

GLEN JUSTICEWhatever is in your bilge goes into the water when you pump it out. If you see a sheen, stop. It is illegal to dump oil, fuel or other chemicals in U.S. waters. GLEN JUSTICE

Recycle. There is much aboard a boat that can be recycled. The obvious items are glass bottles, plastic packages and metal cans. Not-so-obvious items include sacrificial anodes – the zincs – that are replaced seasonally, and the shrink wrap used during winterization. Batteries too can be recycled, as can oil and antifreeze.

SEWAGE AND FUEL

Be tidy about maintenance. When doing bottom work, collect all paint chips and other residue and dispose of it in designated trash cans ashore. Consider using one of the new, lower-toxicity antifouling paints to protect your bottom. Ordinary bottom paints often contain copper, mercury, arsenic or tributyltin, which harm the underwater ecosystem. The new generation of low-copper bottom paints have received good reviews from boating magazines. The October 2007 issue of Practical Sailor has a report on bottom paint.

Mind your sewage! Ask your crew to use restrooms ashore before coming aboard. Make sure your head is a Coast-Guard-approved model, and that it is in working order before you leave port. Show your guests how to use a marine head and tell them to call you if they forget the instructions. Never discharge raw sewage in U.S. territorial waters – it's a violation of federal law.

If you have a holding tank, be sure your Y-valve is locked in position to prevel illegal discharges (the Coast Guard will ding yo if it isn't). Pump and rinse out your holding tank regularly at a pumping station. Many fuel docks provide this service free when you fill up, and marinas often offer regular service for a small fee. Take care not to spill anything during the process. If you do cause a spill, wipe it up promptly using oil-absorbent pads. Use enzyme-based products to help stifle odors. Avoid head-maintenance products that contain quaternary ammonium compounds and formaldehyde.

Fuel carefully. Before you begin fueling, spread oil-absorbent pads around your intake. Because fuel tanks on boats aren't pressurized, they frequently belch fuel out of the intake without warning. If your boat is on a trailer, fill its gasoline tanks while it is on land, rather than when it is in the water. Fuel carefully to avoid spilling fuel or overfilling your tank. Don't let anything distract you. You can buy a new inline fuel-air separator, also known as a vented fill, for between $20 and $140 that will minimize the danger of overfilling. For safety's sake, have someone call out the number of gallons you take in while you're fueling.

Don't try to top off. Leave a 10 percent gap so fuel doesn't overflow. If you do spill fuel onto your boat or the pier, wipe it up with a rag – don't wash it into the water. If you spill fuel or oil into the water, don't try to disperse it with detergent or soap. That only sends it to the bottom, where it's more difficult to clean out. If the spill is large, you must report it to the Coast Guard's National Response Center at 1-800-424-8802 or via VHF radio. Failing to do so could cost you fines and penalties.

Be especially mindful of the bilge, where oil, fuel, antifreeze and other chemicals can collect. To avoid leaks, inspect fuel lines and hoses frequently, replace those that are worn and secure them properly. Never discharge bilge water that has a sheen.

GOOD HABITS

Motor slowly. How you use the boat also matters. Proceed slowly in shallow waters so as not to disturb fish or wildlife. Avoid plowing through underwater vegetation. Watch your wake: Not only can it cause injuries or damage, but it also can exacerbate erosion of the shoreline. If you run aground, don't gun the engine to try to get free. Not only can that damage your engine and propellers, but it also could hurt the sea floor and marine organisms. If you sight a marine mammal such as a dolphin, manatee or whale, slow down and keep at least 100 yards away. It's illegal to feed, harass or injure a marine mammal.

Remember that less is more. Cut back on your consumption of fuel and battery power by keeping your hull and propeller blades clean and in good condition for maximum efficiency. Modern engines reduce far less emissions than those built even five years ago, but there is much you can do to be less reliant on engines and generators – and therefore produce less exhaust. Solar panels and wind generators are two good ways to keep batteries charged without running an engine.

Also, avoid idling your engine unnecessarily. Engines need a proper warm-up, but once they are warm, they are likely to start quickly for many hours. That means there is no need to keep yours running when you're resting in an anchorage or sitting alongside a pier.

Fish sensibly. Don't throw fish waste into the waters around your marina. Discard it over deeper water or save it and use it as chum or bait. Keep only those fish that you will eat and, for the rest, use catch-and-release techniques that will ensure that those you toss back survive. When it comes to fishing, many small things add up. Use circle hooks. Take used monofilament fishing line back to recycling bins ashore. Empty bait buckets on land, not into the water. Never dump live fish or other organisms from one body of water into another.

COMMON SENSE

Spread the word. Keep up-to-date on products and practices that are safe for the environment and share the information with other boaters. Prod your marina's owners to provide pumpout stations, trash cans and recycling bins. If your state has a Clean Marina program, support it and let your marina's management know you care.

Of course, it isn't always easy to be a "green" boater. Miller said he often has to look far and wide during a sailing trip to find a marina that has a pumpout station. "There just aren't enough of them," he said. "Many smaller marinas just don;t have any at all. And even when you do find a spot that has one, it isn't always working, so you have to go somewhere else." As a result, he says, some boaters just give up and pump their sewage overboard – often in violation of federal and state laws.

Occasionally, there are regulatory excesses that end up discouraging boaters from environmental practices. In 2006, a federal court, seeking to crack down on ballast-water discharge from large oceangoing ships, which can transfer invasive aquatic species from one body of water to another, ordered the Environmental Protection Agency to require all vessels in U.S. waters to obtain discharge permits. That would eliminate the longstanding exemption for recreational boats, most of which don't even use ballast-water.

Boat industry lobbyists say that unless Congress acts to counter that ruling, pleasure-boat owners may have to buy expensive permits and retrofit their vessels to meet new requirements. They also may be required to submit written reports to the EPA or state authorities, quantifying any discharges from their boats.

There are several bills in Congress designed to limit the new EPA regulations. Still, boaters who have taken steps to green their vessels say most items involve plain old common sense and very little money.

"I figure that if I'm going to worry about the runoff from hog farms and industrial areas, I should do what I can myself as well," Miller said. "If you don't, you become part of the problem."

GLEN JUSTICEOne easy step toward green boating is to adhere to a simple rule: nothing goes overboard.

Art Pine is a veteran journalist who has served as a Washington correspondent for the Baltimore Sun, the Washington Post, the Wall Street Journal and the Los Angeles Times. He is a licensed captain and a longtime Chesapeake Bay sailor.