Linda Heron, Chair of ORA, made this presentation on the 18th of June 2018, to the Township of North Huron’s Reeve and Council regarding the Howson Dam on the North Maitland River. According to a 19 June article by Adam Bell, Blackburn News, a decision will be made on the future of the Howson Dam by the 27th of July.
On 23 – 24 June of 2017, the upstream Gorrie Dam failed and the Howson Dam was at capacity during an extreme rain event and flood when 175 mm of rain fell in just 7 hours, placing more than 150 property owners at risk and resulting in an estimated $11-million in damages in the Town of Harriston. This severe rain event broke previous records by approximately 40% and was the second highest flow on the North Maitland in the 48 years of record. Fortunately, no one was killed; however, it could have been much worse, as in October of 2015, when a South Carolina flood breached 18 dams, and resulted in 16 deaths.
It has come to ORA’s attention that the Gorrie Dam on the North Maitland River failed as a result of flooding during an extreme rain event on 23 – 24 June 2017, and that Maitland Conservation is considering its options. We understand that no one is more aware of the extremes of a volatile and changing climate than Conservation Authorities, and yours in particular; and we understand the pressure that Conservation Authorities and municipalities are under when communities rally to maintain their coveted mill ponds. However, it is up to all authorities to take a leadership role that places public safety and landscape scale ecological integrity above local individual or group interests.