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Pollution Prevention and Control Plan

Pall Mall Sewer Outlet at Thames River Pollution Prevention and Control Plan (PPCP) Master Plan Class Environmental Assessment

What is a Pollution Prevention and Control Plan (PPCP)?

A PPCP is a long-term strategy to identify, investigate, and reduce sewer system overflows in the City of London.

The study is being developed as a Master Plan under the Municipal Class Environmental Assessment Process, which provides the opportunity for the public and any other stakeholders to provide input.

Mission Statement

The Pollution Prevention and Control Plan provides the City of London with a road map for implementation of infrastructure improvement projects that will mitigate the impacts of wet weather sewer system overflows on the Thames River, in alignment with the City's commitment to environmental stewardship and the protection of water resources.

Why do sewers overflow?

Sanitary sewers can become overwhelmed due to too much inflow or infiltration.  When this happens, the sanitary sewer can back up, causing risk of basement flooding.  Historically, to prevent basement flooding, overflow connections between the sanitary and storm sewer were created.  When overflows are active, untreated wastewater is diverted to storm sewers which outlet to the river.

The City cannot simply remove these existing overflows as they serve the important purpose of preventing basement flooding.

The PPCP is a careful study of all overflows in London and will include field investigation hydraulic modelling, water quality analysis, and strategies to minimize the extent and impact of sewer system overflows.

Notice of Completion - Master Plan


Phase 3

Full details of Phase 3 of the PPCP can be found below:

Executive Summary - Phase 3

Final Report - Excluding Appendices

Final Report - Appendices

Public Information Centre #3: November 1, 2017

Public Information Centre #3 Notice

Public Information Centre #3 Info Brief

Public Information Centre #3 Panels

Public Information Centre #3 Results


Phase 2

Full details of Phase 2 of the PPCP can be found below:

Executive Summary - Phase 2 Summary Report

Phase 2 Summary Report

Public Information Centre #2:  May 28, 2014

Public Information Centre #2 Results

Public Information Centre #2 Notice

PIC#2 Panels

PIC#2 Information Brief


Phase 1

Full details of Phase 1 of the PPCP can be found below:

Executive Summary - Phase 1 Summary Report

Phase 1 Summary Report

Public Information Centre #1: October 3, 2012

Notice of Commencement and Public Information Centre #1

PIC#1 Panels

PIC#1 Information Brief

PIC#1 Summary


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