Boat Washing and Engine Winterization for Boat Owners

Boating activities can be enjoyed without having a negative impact on water quality. DES encourages boat owners to follow boating best management practices (BMPs) to protect water quality, whether they use the services of a marina or perform boat maintenance themselves.

One way to protect New Hampshire waters is to regulate what goes into those waters. Surface water discharges are regulated by the U.S. Environmental Protection Agency and New Hampshire Department of Environmental Services (DES). The state is committed to keeping our public waters clean. DES's authority to enforce discharges into state waters is provided for in the following RSA:

Section 485-A:13

I. (a) "It shall be unlawful for any person or persons to discharge or dispose of any sewage or waste [wash water, antifreeze and detergents] to the surface water or groundwater of the state without first obtaining a written permit from the department of environmental services …"

Boat Cleaning Procedures

If you use a marina, they usually provide a boat wash service. If you wash your boat yourself whether at home or at a marina facility, you are required by law to follow proper boat washing procedures. These procedures include no discharges to surface or ground water (unless the marina has a ground water discharge permit). Ask your marina for more information about boat wash activities and facility policy.

Boat Cleaning - In the Water

Always use cleaning methods that prevent or contain the release of pollutants to surface waters.

• Boats may not be cleaned below the waterline while the boat is in the water.
• When possible, remove the boat from the water, even if cleaning only deck areas.
• Use a spray wash that does not require a water rinse.
• Use a phosphate-free detergent to wash the outside of the boat. Remove the detergent with an absorbent product like a sponge or mop. Extract the waste water from the absorbent product and place it into the wash bucket. (Remember, no discharge!)

Boat Cleaning - Out of the Water

• Wash and rinse boats far from surface water or in marina-designated wash stations where the water can be contained and treated.
• Use environmentally friendly products for cleaning. If you use a marina, ask what products they recommend or have had DES approve.

Engine Winterization

Contrary to popular belief, antifreeze of any kind does not need to be added to a marine engine during winterization. If all water is properly drained, there is little chance that the engine will crack as a result of metal expansion from freezing water.

There are two main types of antifreeze: the traditional ethylene glycol and the preferred less toxic propylene glycol. Although less toxic, propylene glycol, cannot be discharged to surface water or the ground.

The preferred option for engine winterization is flushing the engine with antifreeze, letting it drain, and capturing and reusing the fluids. This option gives the engine a winterization treatment, and prevents the antifreeze from being discharged to a water body. To choose this option, some boats have to make sure their bilge is clean, since the antifreeze must be removed via the bilge. In these cases, bilge socks are highly recommended, and usually can be added during winterization procedures to expedite spring launching. Ask a marina which brand of bilge sock they recommend.

If using a marina's service for winterizing your boat, ask that they:

• Manually drain all water from the engine.
• Do not add antifreeze, unless necessary.
• Use the engine flush technique above.
• Empty all engine fluids during winterization procedures.
• Add a bilge sock to keep the bilge clean.

For more information visit the New Hampshire Pollution Prevention Program web pages at www.des.nh.gov/nhppp, or call (800) 273-6469.