SC rivers rated fair or better in Canty
South Canterbury's rivers are safer overall than those in the rest of Canterbury for recreational contact.
Environment Canterbury's latest summary reveals that 86 per cent of sites monitored in the catchments below the Rangitata were graded "fair" or above for recreation.
For the entire Canterbury region, only 56 per cent of the monitored sites were declared fair or above. ECan water quality scientist Michele Stevenson said the new monitoring season would begin next month.
"Our recreational water quality monitoring is based on water samples taken over summer at popular recreational sites, which are analysed for E. coli," she said.
"We work with other organisations, such as Community and Public Health, to ensure people are informed if areas are not safe for recreation."
According to the regional council's annual report, 10 of the 33 monitored sites below the Rangitata were considered of "fair quality", 13 were considered "good" and six "very good".
Four sites - Loch Laird, Glenburn the Waihao River and the Waihi Gorge - were graded "poor" or "very poor", and therefore unsuitable for contact.
Ms Stevenson said there were a variety of factors that could lead to them not being suitable for recreation, including intensification of nearby land-use, low river flows and discharge of waste.
Sites graded as "fair" might become unsuitable in adverse weather events, she said.
"There are things that can be done to improve water quality, such as riparian planting, or fencing stock out of water ways.
"But it's not something that can happen overnight, you have to take a variety of approaches," Ms Stevenson said.
The Canterbury water management strategy aimed for an increase in swimming sites suitable for recreation by 2020, while ECan's newly introduced measures preventing stock from entering waterways would go some way to addressing the problem, she said.
Over the last two summers, the Orari, Opihi and Pareora rivers have been affected by the spread of toxic algal blooms known as phormidium.
Ms Stevenson said phormidium could cause serious health issues, including rashes on skin contact.
"However, it's a separate issue that we don't necessarily factor into our river quality grading," she said.
"We've been noticing it more, but it might just be because there's been an increase and improvement in our monitoring."
- The Timaru Herald