BoPRC has advised residents that they would not take action on the weed wash up at Okawa Bay on a public amenity basis because it was really a private amenity one which they would need to address themselves if they wanted to have the weed removed commenting as follows:
“While I agree with you that rotting weed isn’t pleasant, I don’t consider it to be toxic. Although it certainly creates an unpleasant amenity effect for those private dwellings. Our scientist confirmed with me that it’s unlikely to be a driver of the algae blooms that have been present. However, once any weed dies and breaks down to the bed of the lake it does become available as nutrient, which is a driver in algae blooms. The presence of lake weed may actually be an indicator of good water quality (clarity), i.e. if there was an algae bloom there wouldn’t be sufficient light for the weed to grow.”
They also clarify responsibilities around weed on the Te Arawa Lakes - including weed harvesting, spraying, spraying limits and managing new incursions of weed on lakes that do not already have invasive weeds present.
Emails on the subject from BoPRC and Okawa Bay representative Richard Amery can be read here.