GREYSTANES High School has dumped its school Streamwatch program after 20 years.
"We wanted to continue it but because we had no one to train us we had to stop it," the school's Streamwatch co-ordinator and chemistry teacher Karen Scanes said.
The axing of the program was prompted by the state government's decision to cut funding for Streamwatch.
Documents obtained by the Nature Conservation Council of NSW under Freedom of Information laws showed Streamwatch cost Sydney Water about $340,000 a year to run.
Under new arrangements which started this month, Sydney Water pays the Australian Museum $100,000 a year to maintain the program.
"Holroyd Council said they would continue to support us if we continued testing, but there was no talk of funding relief [from Streamwatch]," Ms Scanes said.
"As a chemistry teacher, I probably could train the kids but then the school would have to pay for my relief. It's $350 a day for casual relief."
Since 1990 Streamwatch groups, made up of community volunteers, have tested and monitored the water quality of waterways and placed this data online.
Councils, catchment management authorities, landowners and land managers have used this data as an early warning system for pollution, a historical record of how waterways have changed, and to evaluate the effects of remediation projects.
Greystanes High School tested and monitored the water quality at Darling Street Creek every week.
"The council does not have plans to fund the [school's] Streamwatch program," a Holroyd Council spokeswoman said.
"The council has conducted its own water quality monitoring program for many years and will continue to monitor water quality in our local creeks."