"Results are received within 48 hours and are updated on LAWA and Horizons' websites, where interactive maps show each of the swim spots marked by a red, amber or green location marker to indicate that week's results."
The traffic light system used is part of the Ministry of Health and Ministry for the Environment guidelines that provide guidance to councils and district health boards.
"Gravel bed river sites and lakes are also tested for cyanobacteria, which is an algae that can be potentially toxic. Horizons will be keeping an eye on this during summer and also reporting these results on the websites," Roygard said.
"However, we do urge public and their animals to stay out of the water if they are at a river and see black or dark brown, slimy mat-like growth on the stones that may also be musty smelling. In lakes, potentially toxic algae are visible as bright green 'blooms' with surface scum often found at the lake edge."
In collaboration with regional councils, the LAWA project has introduced a new water quality display on the swim spot page that gives results from the past five swim seasons.
"In addition to water quality, LAWA's website includes local weather, tides, surf, water temperature, flow-rate, whether a site is patrolled by lifeguards, and information on each site's facilities such as camping and toilets, and fact sheets on monitoring, algae and faecal indicators.
"We do want to remind people that water quality is just one factor in a number of potential health risks. We ask the public to be aware of hazards such as unstable banks and cliffs, submerged logs, and tsunami warnings and rips at beaches."
Roygard noted that sampling is done weekly, so results may not always reflect the water quality for the whole week.
"A general rule is if the water looks clear and it's three days after rainfall, you should be good to go."
