1. Sail, don’t motor

This may seem like the most obvious of tips, but it is often all too easy to reach for the key and turn the engine on if the wind dies or isn’t producing the optimal speeds that you desire. If, on passage, the wind dies and you have the luxury of time and no pressing schedule, and you’re not in a situation that requires immediate action to get you out of a dangerous environment, then sail. Yes, the pace of your passage may slow, but your energy consumption, and consequently your impact on the environment, will drop too. And not only that, it may also make the passage more enjoyable, giving you the opportunity to appreciate the journey, the wildlife and the landscape at a more relaxed pace and without the background drone of an engine.

With practice, and in the right conditions, it is also possible to sail on and off your anchor or mooring buoy. Not only will this provide interesting challenges for the crew, but it will also hone your sailing skills so that if you find yourself in a situation where your engine fails or proves unreliable, you will be able to employ a back-up plan.

Use paddle power instead of engines as a more environmentally friendly mode of transport.

2. Reduce your emissions

Everything we use on board now requires power, whether that’s to charge your phone, smartwatch or device, or run your chartplotter, depth sounder or AIS. However, producing that power in turn produces emissions, which increases your carbon footprint. To reduce it, look for sustainable energy sources, such as solar panels, water generators or wind turbines. Use solar-powered torches instead of battery-powered ones and turn off any devices when they’re not in use to save power. If there’s an option, choose energy-efficient appliances and if you’re not using your boat over the winter months or for long periods of time, consider purchasing a trickle charger. These prevent batteries from running flat when not in use and keep them topped up by charging them at very low amperage.

3. Anchoring

Be considerate with where you anchor. That bay with its pristine beach and turquoise-blue waters may seem like the ideal spot, but if the seabed is home to a fragile marine ecosystem you could do significant and irreversible damage by dropping your hook there. Avoid all areas that are home to kelp forests or seagrass, which provide nursery grounds for young fish and breeding crustaceans and mammals, or on coral, and only anchor in designated anchorages or areas of mud or sand.

Be careful where you anchor, so as not to damage any fragile ecosystems.

4. Marine protected areas

Marine Protected Areas (MPAs) are designated zones around the world that are recognized as being important ecosystems that need to be protected against environmentally damaging activities. They vary in size and what they aim to protect, but the ethos behind them is that they cover fragile ecosystems and their supporting wildlife, protecting them from destructive human activity through rules and regulations. Sites of historic shipwrecks are also often covered by MPAs and although some of these areas ban all human activity within them, the majority allow some access, with restrictions covering anchoring and fishing activities or admission during certain marine wildlife’s breeding seasons. When passage planning, check for any MPAs within your area and respect any rules or regulations that they may be subject to.
It is often easy to forget when exploring new places that you are not only a foreigner to the country or location that you are visiting, but also an outsider to the environment, which is why it is so important to be respectful to that environment and any wildlife you may encounter. So, while it can be incredibly exciting to spot a dolphin or whale, or other large marine mammal or fish, please keep a respectful distance from them.

5. Black, grey and bilge water

If possible, install a holding tank for storage of black water (sewage) and only pump out ashore to prevent toxic pollution entering the waterways. It’s already a requirement in many countries around the world to do so, and most marinas have facilities that cater for safe disposal and treatment of the waste. If you do have to discharge untreated black water offshore, make sure you do it in deep water and a long way from shore, where any risk to marine or human life can be minimized. Check the relevant country’s rules and regulations, too, as they do vary considerably: Norway, for example, allows black water discharge 300m (985ft) offshore, whereas in the Baltic Sea, Germany requires you to be at least 12nm offshore. Look for eco holding tank digester treatments, too, which contain bacterial ingredients that help break down organic matter.

Grey water (waste water from showers and sinks) is usually pumped out direct, but it is still a source of pollution owing to chemicals in cleaning and hygiene products, so be considerate with what you use. Some countries require grey-water as well as black-water tanks, so check local regulations.

Fit and check regularly filters in bilge-water discharge pipes, as bilge water often contains traces of oil, fuel and emulsions that can be harmful to marine life if discharged direct into the sea.

6. Be responsible with your waste

If you are cruising in an area popular with sailors, then waste disposal should be relatively simple as most marinas and harbours around the world now offer extensive facilities, including recycling. If possible, separate out your rubbish on board to make it easier to dispose of onshore, and look for companies that will recycle old ropes, sails and electronics. Larger marinas usually have waste bins for disposing of old paint, oil or fuel, as well as associated sundries. If using general bins near the harbour, make sure all bin bags are securely tied, so that waste doesn’t inadvertently blow out into the water.

Try to minimize the amount of waste you generate, too. Boats are small spaces, and if you’re cruising in an area where the options to dispose of or recycle waste are limited then it can build up quickly on board. Add in a warm climate and you’ll find your boat takes on a particularly noxious odour. If possible, only buy the food you need for that particular passage and buy it loose or in packaging that you can reuse, so that you don’t end up with bags and bags of rubbish to dispose of. Never, ever, throw waste overboard – even orange peel can take two years to degrade, and plastic pollution can be extremely harmful to the marine environment (see box).

7. Maintain your boat

Oil and fuel leaks, flaky paint, engines that don’t run efficiently – all these factors contribute to your environmental footprint, so if you want to be more sustainable at sea it’s important to look after your boat. Not only will doing so extend the life of your boat, preventing costly repairs and saving you money in the long term, but your impact on the environment will be minimized, too, with fewer contaminants entering the water. A well-maintained engine will also run cleanly, at its maximum efficiency, so reducing fuel consumption and emissions.

8. Be vigilant for invasive species

A clean bottom, with minimal drag, not only increases efficiency, under both sail and motor, but it also prevents the spread of any unwanted wildlife. If you’re sailing long distances, and in different climates, watch out for non-native invasive species hitching a ride. Tubeworms, barnacles, sea squirts, biofilm and fast-growing species such as zebra mussels like nothing better than attaching themselves to hulls, keels, propellers, shafts, impellers and rudders, but they are a big threat to biodiversity as they can be hard to control and eradicate, at the cost of native species. Regularly inspect your hull and scrub off with eco-friendly cleaning products as required.

Zebra mussels are an invasive species that can harm local biodiversity.

9. Eco-friendly cleaning

Whether it’s for your skin or your decks, choose cleaning products that are eco-friendly. Whatever you use ends up in the sea – whether that’s run-off from scrubbing the hull or decks, washing-up detergents, or chemicals in your shower gel and shampoo, they’re all potential pollutants. Choose products that don’t contain phosphate, a chemical that can cause oxygen depletion and algal blooms following nutrient enrichment, and avoid anything with microplastics, potassium hydroxide, ammonia or chlorine.

Use eco-friendly products when cleaning your boat to prevent releasing pollutants.

10. Reef-friendly sunscreen

Another product that ends up in the sea with potentially harmful side effects is sunscreen. According to the Smithsonian, it is estimated that around 14,000 tons of sunscreen enters waterways around the world each year, from being washed off when you swim in the sea or run-off from wastewater. That’s a huge amount of sunscreen, and the effect it is having on marine life, and particularly key ecosystems such as coral reefs, is very worrying. Studies into the impact of sunscreen are ongoing, but there is strong evidence that chemicals in it, such as oxybenzone, octinoxate, 3-benzylidene camphor and nano-titanium dioxide, stress the fragile corals, accumulating in their tissues and causing damage to their DNA, abnormal development and, in high concentrations, bleaching. To mitigate any risk, look for ‘reef-friendly’ sunscreens and wear UPF clothing, hats and sunglasses, as well as avoiding exposure to the midday sun where possible.

Choose reef-friendly sunscreen that won’t harm delicate ecosystems.

11. Buy local

Visiting local markets and shops is a great way to get a real sense of a place and immerse yourself in local life. Here, rather than the homogenized aisles of the supermarket, where you can often buy a carbon copy of what you buy at home, you get to sample the best local products. Not only are you helping to support local businesses, but market-fresh food is usually delicious and a great way to taste local delicacies. Yes, it may have a shorter shelf life, so be less suitable for longer passages, but it is usually seasonal and from local suppliers, so will have a smaller carbon footprint. Take your own containers with you and you can reduce the amount of single-use packaging you take home, too.

Local markets are a great source of fresh produce with a smaller carbon footprint.

12 Mini beach cleans

Sadly, pristine beaches devoid of litter are now a thing of the past, with a significant amount of the estimated 14 million tons of plastic waste that enters the oceans around the world each year ending up on our shorelines. Plastic bottles, packaging, vapes, cigarette butts, nurdles and other land-based waste is not only an eyesore, but can be a danger to marine life too. We all need to play our part in clearing it up, so every time you run ashore, take a bag with you and spend five minutes picking up rubbish. It may not seem long, but small actions lead to big changes and if everyone participates it will make a difference.

Get your kids to help with mini beach cleans and help look after the environment.

The key to sustainable sailing:
As the Native American Chief Seattle said: “Take nothing but memories; leave nothing but footprints.”