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Check, Clean, Dry

Do your bit to protect the lakes and rivers that you love.

All it takes is one tiny fragment of hornwort or a single freshwater gold clam. If aquatic pests hitch a ride on your gear they can spread to previously unaffected waterways - choking our lakes and rivers, make them murky, and out-competing native wildlife.

Rules for public boat ramp users

The Bay of Plenty Regional Pest Management Plan 2020–2030 requires that all public boat ramp users certify that their boat is free from freshwater pest fish and weed where a self-certification checkpoint is present.

Everyone can play their part by following the rules.

  1. Don’t leave boat trailers in any water body unless you’re launching and/or retrieving boats.
  2. Don’t transport ballast water from any water body to any other location.
  3. Boat ramp users entering any Bay of Plenty water body must make sure their vessels or craft (including trailers) are free from freshwater pest fish and freshwater pest plants including fragments.
  4. Where there is a self-certification checkpoint, boat ramp users must complete a self-certification form before launching. The form must either be submitted electronically or displayed in the vehicle and left at the boat ramp where the boat was launched.

Biosecurity staff will be visiting public boat ramps throughout summer to help lake users understand the rules and check that they are complying with them. Lakeside self-certification checkpoints, with instructions, have been set up at boat ramps around the Rotorua Te Arawa lakes.

Ways to self-certify:

How to Check, Clean, Dry


  • Remove any visible matter, including any clams you can see, along with plant material or mud. Drain all river or lake water.


  • Washdown your gear, vehicle, watercraft, and trailer that has been in contact with river or lake water with tap-water onto grass, beside the waterway or at home and not into a stormwater drain system. This will remove any remaining invisible material.
  • For absorbent surfaces and materials that have been in contact with river or lake water (including carpet on trailers) use an appropriate treatment in the treatment options table on the MPI website.
  • Treat residual water that always occurs when on-board ballast bladders or tanks have been pumped.

Cleaning options


Treatment time2


10% mix (1 in 10 ratio)

Immerse for 1 hour

Hot water1

Above 60°C

Between 50-54°C

Above 45°C

Soak for at least 1 minute

Soak for at least 5 minutes

Soak for at least 20 minutes



Until solid (overnight)

1 60°C – hotter than most tap water; 45°C – uncomfortable to touch
2 Allow longer times for absorbent items.


  • Allow gear to dry to touch, inside and out, then leave it to dry for at least 48 hours (2 days) before using again.
  • Dry areas inside the watercraft where water has pooled, for example with an old towel, and then leave the craft to dry for at least 48 hours (2 days). The hull of a watercraft will dry when towed.