Swim spot monitoring gets underway across the Horizons Region

Horizons environmental monitoring team leader Ian Hurst says staff began sampling water and surveying riverbeds on Monday. The team will monitor more than 80 popular swimming spots each week until 30 April 2027.

“We test for E. coli at freshwater sites and enterococci at coastal sites, as high amounts of these bacteria can suggest faecal contamination of a waterway,” says Mr Hurst.

“If we find high levels of these bacteria at a site, it suggests other pathogens, which can make people sick, might also be present.

“Because E. coli and enterococci can’t be seen with the naked eye, regular monitoring of swimming sites provides valuable information for people deciding where to swim.”

Water samples are taken once a week before being analysed at an independent lab, with results uploaded to the LAWA website, www.lawa.org.nz, says Mr Hurst.

“If results on LAWA suggest your usual spot is unsuitable for swimming, you can check out the water quality of monitored sites nearby that might be suitable. While it’s not ideal when your favourite spot isn’t at its best for playing in, it does provide a great opportunity to explore somewhere new.”

People should also keep an eye out for cyanobacteria, also known as potentially toxic algae, at waterways this summer, says Mr Hurst.

“Cyanobacteria can appear as black or brown mats on rocks in a river or washed up on the riverbank. In lakes, cyanobacteria float freely in the water, causing the water to become murky, or they form green scums on the lake’s surface.

“Contact with cyanobacteria can cause illness in both people and animals. Dogs are particularly vulnerable because they like the musty smell of the black mats, but ingesting them can be seriously harmful.

“Be sure to keep an eye on your pets around waterways, especially if you see exposed mats of black or brown algae in the area. As we’re expecting dry weather this summer, river levels might be lower, exposing more of these mats.”

Mr Hurst says people should also consider wider water safety issues before heading out for a swim.

“Please stay out of water if it has rained heavily within the last 72 hours, as this can create faster-flowing water and contribute to higher levels of faecal contamination.

“It is also important to check a site carefully before entering the water, especially after heavy rain. Check for submerged hazards each time you visit, as conditions may have changed since you were last there.

“Rivers and beaches across Aotearoa New Zealand can be unpredictable, and their power is easy to underestimate. Do not enter the water alone, actively supervise children, and stay out if you are not a confident swimmer.

“Avoid swimming near unstable banks or cliff faces, and call 111 if an emergency occurs at a waterway.

“We want everyone to enjoy the region’s waterways safely this summer. By checking conditions before you leave home and making sensible decisions once you arrive, you can help keep yourself, your whānau, and your pets safe.

“More information about how to stay safe in and around rivers and beaches can be found at www.watersafetynz.org.”