Millbrook Dam Environmental Assessment Study Dan Marinigh CAO/Secretary-Treasurer Otonabee Region Conservation Authority October 20, 2015 Otonabee Conservation …. providing leadership to achieve healthy watersheds

Objectives for Today Recap the history of the project Provide an update of the more recent work Seek your input Otonabee Conservation …. providing leadership to achieve healthy watersheds

Why an EA Study The Millbrook Dam – 120-metre long earth-filled embankment dam constructed in the early 1800’s – The dam suffers from issues and problems common of dams of this age – Hazard potential classification is “high” – The existing overflow weir and spillway are incapable of discharging flood flows and the dam is inadequate to prevent toppling and/or sliding – Dam failure could result in loss of life, property damage, environmental harm and economic and social disruption Otonabee Conservation …. providing leadership to achieve healthy watersheds

Purpose of the EA study To identify, evaluate and investigate a reasonable range of options to resolve the problem of incremental flooding caused by the potential failure of the dam Otonabee Conservation …. providing leadership to achieve healthy watersheds

The EA Study Launched in 2012 – draft completed in late 2013 Evaluated a range of options and subject to public consultation Recommended preferred option: – Removal of existing 7 m wide weir and spillway and replaced with a new, 36 m stepped weir capable of passing 100 m3/second – Crest height of new weir would be 0.5 m lower than the crest height of the present weir – Headpond would be excavated to natural depth – Earthen embankment would be strengthened and made impermeable. Otonabee Conservation …. providing leadership to achieve healthy watersheds

The EA Study The EA Study Report was presented to the ORCA Board in November The Board deferred a decision on the approval of the EA Study, primarily because it needed to better understand the financial implications of the recommended preferred option ORCA continues to consider the EA Study report to be a draft report Otonabee Conservation …. providing leadership to achieve healthy watersheds

Meanwhile The province adopts new dam safety guidelines – came into effect April 1, 2013 ORCA commissions a review of its earlier dam safety assessment for the Millbrook Dam to ensure that it will satisfy the new dam safety guidelines The review identifies some issues with the “inflow design flood” value, a key value that determines the design criteria to be met when contemplating a new dam or repairs to an existing dam Otonabee Conservation …. providing leadership to achieve healthy watersheds

Challenges Before moving forward ORCA had to find solutions to two key issues: 1.How to pay for the project 2.Understanding the significance of a new “inflow design flood” value and its implication to the draft EA study. Otonabee Conservation …. providing leadership to achieve healthy watersheds

Solutions to The Challenges How to Pay for the Project: – In April the ORCA Board adopted a policy on the management of water and ice control structures. – The policy identifies how ORCA will pay for major repairs and replacements of its portfolio of water & ice control structures. – ORCA received a provincial and federal grants under the Small Communities Fund for $2.238 million Otonabee Conservation …. providing leadership to achieve healthy watersheds

Solutions to The Challenges Inflow Design Flood Value: – ORCA has entire dam safety assessment re-done; all previous work is reviewed, input values are validated and documented and all analysis is brought together into one standalone report – Analysis undergoes a peer review process – Review finds that the “inflow design flood” changes from 100 m3/second to 181 m3/second – Review completed in January 2015 – ORCA Board adopts the findings Otonabee Conservation …. providing leadership to achieve healthy watersheds

Moving Forward The goal for moving forward is to achieve the following outcomes: – To ensure that the requirements of the Class EA process for revising the EA study and selecting the preferred solution are met. – That the preferred solution must meet the design criteria established under the Lakes and Rivers Improvement Act so that it may ultimately be approved for construction. Otonabee Conservation …. providing leadership to achieve healthy watersheds

Approach for Moving Forward Step 1: – Investigate, evaluate and select a structural solution that retains the head pond, safely passes the “inflow design flood” value and mitigates issues with the earthen embankment (new way to implement the preferred option) – Review and update cost estimates for the new preferred option and the previous options A & B – Consult on the revised preferred option Otonabee Conservation …. providing leadership to achieve healthy watersheds

Approach for Moving Forward Step 2: – Update evaluation of environmental effects – Obtain Board approval for the revised EA Study Report Step 3: – Undertake mandatory Notice of Filing of an Addendum and Filing of Project Approval Otonabee Conservation …. providing leadership to achieve healthy watersheds

May Jan 2016 JulSeptOctNovDecAugJun Retain Consultant 1 st Public Info Session Investigate/ Evaluate & Select Design Alternative & Update Cost Estimates Public Review of Design & Updated Cost Estimates Notice of Filing an Addendum Update Environmental Effects Evaluation Notice of Project Approval May 15- Jul 6 Jun 10 Jul 6- Sept 18 Oct 15- Nov 16 Nov 16 Jan 15- Feb 15 Mar 15 Proposed Millbrook Dam EA Process & Timeline FebMar Apr 2015 CLC Meeting Board Decision to Proceed Apr 16 Board Adoption of Revised EA Study Report Dec 17

Progress to Date Public Engagement: – June 10 Information Session – Updated materials on ORCA website – Letter updating parties on mailing list – Letter updating Aboriginal communities and organizations – Newspaper ads for the today’s Public Information Centre Funding: – Announcement of SCF grant for $2.238 million – Special benefiting capital levy to be included in 2016 proposed budget Revision to EA Study: – Retained HATCH to identify a new structural solution for option C, update costs and prepare documentation for addendum Otonabee Conservation …. providing leadership to achieve healthy watersheds

Next Steps October – November: – Today’s Public information Center – 30 day comment period – Consider public input and update evaluation of environmental effects December: – Meet with Community Liaison Committee – Board decision on proposed Addendum January – February: – Issue Notice of Filing an Addendum – 30 day comment period March: – Issue Notice of Project Approval – Issue tender for design and construction project management Otonabee Conservation …. providing leadership to achieve healthy watersheds