It's a class project with wide-reaching implications — chemistry students from Redeemer University College in Ancaster have found extremely high levels of potentially harmful bacteria at three Hamilton waterfalls.

The second-year analytical chemistry class has been doing water testing at five Hamilton waterfalls this semester. They found high levels of E. coli, total coliform and other bacteria at Chedoke Falls, Westcliffe/Cliffview Falls and especially Mountainview Falls.

'If I was walking by and I was thirsty and saw these streams, I'd probably drink from them. This is crystal clear water. I was surprised at the level of potentially harmful bacteria—Adam Hollander, student researcher

The students presented their findings Thursday to an audience that included the city, Hamilton Conservation Authority and Royal Botanical Gardens. The project opened their eyes to hidden aspects of the creeks, they said.

"If I was walking by and I was thirsty and saw these streams, I'd probably drink from them," student Adam Hollander told the audience. "This is crystal clear water. I was surprised at the level of potentially harmful bacteria."

The acceptable level of E.coli for safe swimming set by the province is 100 E.coli per 100 mL. In September, the students found levels of about 110,000 E.coli at Mountainview Falls. In October, it was about 80,000.

Total coliform reached more than a million parts per 100mL.

The high levels are likely related to the sewage lines at older homes incorrectly connected to storm sewer lines, said Mark Bainbridge, the city's acting manager of clean harbour.

The city is in the midst of a pilot project in three areas — Spencer Creek, Chedoke Creek and Red Hill Creek — to determine the extent of the problem. Working with homeowners, project staff are using methods such as cameras and dye to find incorrectly connected lines, he said.

The city has already corrected about 50 cross connections, he said. The cost is hefty — about $15,000 per home. The city has a list of homes that have possible cross connections, but some homeowners with the issue may not know it yet.

It's an expensive problem but it needs to be addressed, said Tys Theysmeyer, head of conservation with the Royal Botanical Gardens.

"At the end of the day, water is the most important thing to life. You can't beat that one," he said. "At the city, they're struggling with the situation where we haven't valued clean water very much."

The students, most of whom are majoring in chemistry or biology, have a newfound interest in water quality. The students are excited about doing research that benefits the community, said assistant professor Darren Brouwer.

"When they leave here, they probably won't remember everything I lectured to them, but they'll remember this."