Ontario's Environmental commissioner has released a report calling for legislation to protect the province's groundwater supply to the public.

"How can we trust a ministry to protect the environment when they have made it clear to the public that they have no such intention?" asks commissioner Gord Miller.

The commissioner's report, entitled Protection of Ontario's Groundwater and Intensive Farming, questions the safety of groundwater, which is supplied to three million people in the province.

Miller points to larger livestock farms in Ontario, which produce more manure or agricultural run-off, and, hence, a higher risk of groundwater contamination.

Some experts have said this was the scenario that plagued Walkerton with the deadly E. coli bacteria.

"Time will tell if agricultural run-off was the source of E. coli contamination of the wells at Walkerton. However, you don't have to look long or too far to find examples of environmental damage caused by manure management from large livestock operations." says Miller.

Opposition members say Ontario's water problems are in such dire straits that even the commissioner -- appointed by the Premier himself, had to speak out.

"What today represents is that even Mike Harris' own buddy, own appointee, can't defend this government's sad record when it comes to protecting Ontario's environment," says NDP Leader Howard Hampton.

The Premier's office says Mike Harris agrees more work needs to be done and that the government is already taking action. The environment minister is still on vacation.