Noise & wash

Cutting noise and exhust fumes

By 2011, the Government has specified that 5% of fuel must come from renewable sources like biodiesel.
Exhaust emissions are made up of carbon monoxide, hydrocarbons, nitrogen oxides and various pollutants. These vary depending on whether the engine is two-stroke, four-stroke or compression-ignition.
New boat engines are now highly efficient, due to requirements in The Recreational Craft Directive.

A badly maintained engine consumes more fuel and expels more emissions than a well maintained one, so ensure your engine has a regular service
Use a four stroke outboard engine instead of two stroke. Two stroke engines burn more fuel, can be noisier and emit lubrication oil with their exhaust fumes.
Fitting noise insulation around you engine can reduce airborne noise by up to 85% causing less disturbance to wildlife and making life on board more comfortable.
Products are available that fit between engine and shaft reducing structure borne noise by up to 89%
Bio diesel produces mostly carbon dioxide and water. Most diesel engines can easily be converted but check your guarantee first
When buying a new boat for inland waterways, consider an electric powered craft. They have no exhaust emissions and are very quiet
Good engine trim, matching your speed to conditions and balancing your boat will all lead to greater fuel efficiency.

Find out about the benefits of electric boats at www.electric-boat-association.org.uk

Download the British Marine Federation’s guide to the RCD

Find out where you can fill up on biodiesel - www.biodieselfillingstations.co.uk and convert your boat to biodiesel - www.bloomingfutures.co.uk

Search for sound proofing suppliers at www.ybw-directory.com/Marine_Directory/home.jsp

Follow Honda’s advice and ‘save a gallon’ - http://www.ybw.com/ybw/honda/gallon.html

Shoreline and bankside habitats support a rich variety of wildlife. Even minor damage can result in a decline in number of birds and wildlife that feed on mudflats, salt marshes and reed beds.
In shallow water your boat will travel more efficiently if you reduce engine speed.
Your wash can erode banks, disturb moored boats and even loosen their moorings.

Slow down if you are creating excessive wash – it can erode banks, disturb nesting birds and damage sensitive vegetation.
Slow down immediately if there are waves to the bows or stern of the boat. You are likely to be using more fuel than necessary with no increase in actual speed.
Slow down immediately if there are waves to the bows or stern of the boat. You are likely to be using more fuel than necessary with no increase in actual speed.
The further a craft is from the bank, the less impact its waves will have. Where possible, try to keep a safe, reasonable distance between your boat and the bank.
Hull and propeller design have a major influence on wash. Short full bows give high boat waves, while longer and finer bows reduce wave making. Multihulls are often low wash in design.
Good use of throttle and boat handling skills can reduce wash as well as improve fuel efficiency. Take a training course to improve your skills.
When you go ashore, use recognised landing places.
A well balanced and clean propeller will throw up less sediment and reduce the impact on the underwater environment.

Take the RYA’s Inland Waterways Helmsman’s Course. Find your nearest training centre at www.rya.org.uk

The Broads Authority provides useful advice in its ‘Boating Basics’ – www.broads-authority.gov.uk

Find out the science on boat wash and boat design by searching The Green Blue's scientific papers database