WELCOME Paris Flood Risk Mitigation Municipal Class ... · Paris Flood Risk Mitigation Municipal Class Environmental Assessment Public Information Centre No. 2 Paris Fairgrounds Exhibition

WELCOMEParis Flood Risk Mitigation

Municipal Class Environmental Assessment

Public Information Centre No. 2

Paris Fairgrounds Exhibition CentreTuesday January 14, 2020

6:00 pm - 7:30 pmPresentation at 6:30 pm

Introduction

Historical Context

Existing Flood Mitigation Strategies

Overview of Class EA Activities

Presenting the Preferred Management Strategy

Next Steps

Questions

Content

County of BrantPublic Information Centre

Study Purpose

The purpose of the Class EA study is to review alternatives to further mitigate flood risks in Paris. Existing Paris Flood Protections Works were completed in 1979 and are in need of maintenance and enhancements. There are existing public and private assets that need to be protected along with a risk to public safety that must be mitigated.

Why now?

A condition assessment was completed in April 2019. This investigation found that the flood protection works are in need of maintenance.

The use of updated modelling techniques has found that the level of protection currently in place may not be as high as previously understood.

The County of Brant has received Federal funding to undertake this study.

Introduction


Paris


Regulatory Flood Event


Historical Flooding Events


The high level of the Grand River is shown under the William Street Bridge in downtown Paris in the flood of May 1974. –Paris Museum & Archives

Volunteers place sandbags alongside the Grand River before the flood of May 1974. – GRCA

The intersection of Mechanic Street and West River Street during the flood of 1947. – Paris Museum and Archives

High water during the 1947 flood. –Paris Museum & Archives

A view of the high waters looking towards a home on Elm Street, with the William Street bridge in the background (1912). – Paris Museum and Archives

The back of the Grand River Street shops (1912). – Paris Museum and Archives

January 1979 Ice Jam Flooding



March 1979 Ice Jam Flooding



Floodwaters affected residents of Willow and Elm Streets in Paris

Project Overview


The following site investigations were completed as part of the “Paris Flood Protection Condition Assessment” completed in April 2019.

Condition Assessment


Studies Completed• Visual Condition Assessment• Geotechnical Assessment• Building Inspections• Stability Analysis• Hydraulic Assessment

Study Findings• Dykes require maintenance• Portions of the dykes do not meet stability

factors of safety• Portions of dykes do not provide protection

against the 100-year flood.

Class EA Activities


Completed EA Activities

• Hydraulic Modelling

• Natural Heritage Investigations

• Fluvial Geomorphological Assessment

• Cultural Heritage

• Archaeology

• Flood Damages Assessment

• Develop Alternatives

• Evaluate Alternatives

• Selection of Preferred Alternative

Enhancements

• Flood Emergency Response Plan - ongoing

• Interior Drainage Assessment - ongoing

Alternative Solutions


Do Nothing

No improvements or changes.

Leads to further deterioration and

potential dyke failure.

Undertake Maintenance and Repair Activities

Maintain current location and height of dykes.

Remove or relocate trees and overgrown vegetation

on dykes.

Repair retaining walls to address localized failures.

Reconstruct dykes with stability factor of less than

1.0.

Increase Level of Protection to 100-Year

Flood Level

Reconstruct and raise dykes and walls to the

100-year flood elevation plus 0.3 m freeboard (to

account for climate change impacts).


on dykes.

Reconstruct and raise dykes with a stability

factor of less than 1.0.

Increase Level of Protection to Regulatory

(Approximately 500-Year) Flood Level Reconstruct and raise dykes and walls to the

Regulatory flood elevation plus 0.3 m

freeboard (to account for climate change impacts).


on dykes.

Reconstruct and raise dykes with a stability

factor of less than 1.0.

Example Cross Section Concepts – GW2 and N1


N1

GW2

Easement Requirements


Implementation Plan


The following list shows a potential implementation schedule, based on the prioritization score of each section.

Priority List

Next Steps


PIC #1July 11, 2019

PIC #2Jan. 14, 2020

Study CompletionSpring 2020

Construction2021?

Finalize preferred alternative design considering public feedback

Completion of Project Report

Notice of Completion and 30-day public review period

Detailed design and construction (not part of this project)

Questions


Documents

WELCOME Paris Flood Risk Mitigation Municipal Class ... · Paris Flood Risk Mitigation Municipal Class Environmental Assessment Public Information Centre No. 2 Paris Fairgrounds Exhibition