Pressured by public anger over the deaths of six people in May from an E. coli outbreak in the water system of Walkerton, Ontario, the provincial government promised yesterday to spend $162 million to upgrade water systems and sewage treatment plants. Officials also announced new regulations to monitor and control the quality of drinking water. The E. coli contamination, which sickened about 2,000 of Walkerton’s 5,000 residents, is believed to have been caused by runoff from massive cattle feedlots. Since the tragedy, Ontario’s Conservative government has come under fire from citizens for privatizing water testing and making sharp cutbacks in health and environmental spending, including funds for monitoring water supplies.