A key concept for recreational equipment decontamination is that the effectiveness of the treatment depends on the activity and the type of AIS.
Bottom line: Hot water kills AIS, while rinsing, flushing or high pressure washing removes them.
Inspection and Cleaning Manual for Equipment and Vehicles to Prevent the Spread of Invasive Species (Bureau of Reclamation 2012)
If aquatic recreational equipment has been left in the water for less than a day, key actions to prevent the spread of all AIS are:
The intent of these actions is to clean off any visible large-bodied organisms attached to or in watercraft or recreational equipment. Draining can also remove small organisms such as zebra mussel veligers, however, additional steps are needed to remove small-bodied organisms from other parts of the equipment. Those can be easily rinsed off or die out of water in a short period of time. Added precautions that improve treatment effectiveness are to:
Notes: Young mussels can survive in standing water for 24 days at 50°F, 8.5 days at 59°F, or 4.5 days at 86°F. It is recommended that even a simple hull rinsing with a garden hose and running water through the live well system can be effective. Rinsing of recreational equipment is an effective way to clean off species not visible to the naked eye.
If aquatic recreational equipment has been left in the water for more than a day, the following decontamination methods are recommended:
Notes: All equipment surfaces exposed to surface water, especially if left in the water for more than a day on invasive mussel infested waters, should be decontaminated.
Young invasive mussel settlers are difficult to see with the unaided eye, but on smooth surfaces they feel like sandpaper. Treatment using 140°F water will also kill Eurasian watermilfoil, New Zealand mudsnails, and spiny waterfleas at various exposure times. Treatments are more effective with longer drying times and hotter water.
After removal of aquatic plants and animals, follow these steps:
Notes: Generally, residential hot water heaters are set at 120°F. However, temperatures at the nozzle will be lower because of the water’s heat loss to pipes, hoses, ambient temperature, etc. Commercial car washes typically use water pressure of no more than 1,500 psi and car washes rarely have water hotter than 100° F.
If recreational equipment is fouled, certified or professional decontamination services are highly recommended and may be required based on local, state, or tribal regulations.
Summary: Recommended actions for day users are: inspect, clean off, drain, rinse (with low pressure, hot as possible) and dry for more than five days. For recreational equipment left in zebra mussel infested waters for more than a day, do all of the above, except use high pressure, hot water for exterior surfaces, and low pressure hot water for interior components.
Clean Wetsuits, Clean Water (Lake George Association)