A SWIM and picnic at Lake Ainsworth led to a trip to the hospital and a bad case of gastro for members of five Lennox Head families.
Rob Clarke said he was struck down with vomiting and diarrhea after swimming at the lake on Monday, January 9.
"Lots of families went swimming and then everyone came down with the same symptoms of gastro and diarrhea a few days later," he said.
Mr Clarke said his illness cleared up after a day but his six-year-old son Gus was sick for three or four days.
"Our kids all happened to get sick at the same time and the more people we spoke to around town the more we heard about it."
Another resident, who did not wish to be named, said they believed about 20 people had become ill.
The resident said there had been heavy rain on the Friday before their swim.
NSW Health recommends people do not swim within three days of heavy rain in estuaries or rivers.
North Coast Public Health director Paul Corben said Ballina Council had notified his department of the illnesses being reported.
"...feedback is there is no indication of any particular problems at Lake Ainsworth. However, swimming in the lake (or elsewhere) after heavy rain should be avoided due to risk of becoming ill."
But Jill Young of Maclean said she wasn't worried about her son Joseph, 9, swimming in the lake yesterday.
"We always call it the Coca-Cola lake because of the colour and our kids love it," she said.
Ballina Council Regulatory Services group manager Rod Willis said regular tests on the water quality were published on a website called beachwatch.
"We are taking it seriously and we have reported it to NSW Public Health, but all our testing this summer has shown the water quality is good."
"If we do receive results that indicate swimming should be prevented we advertise that locally," he said.
Ballina Environment Society President Lyn Walker said she believed rain caused increased nutrients to flow into the lake.
"Where there is a guttering alongside the surf club, stormwater runs straight into the south-east corner of the lake."
She said more signage was needed to educate people about the risks involved in swimming after rain and residents should speak out if they see dogs in the lake.
"I think people ought to be aware of the problem of dogs and E. coli and they should talk directly to people who take their dogs into the lake."
Would you siwm in Lake Ainsworth after rain? Leave a comment below.
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