HomeMy WebLinkAboutINS-13-020 - Kolb Creek - Class Environmental Assessment
REPORT TO:
Community & Infrastructure Services Committee
DATE OF MEETING:
September 30, 2013
SUBMITTED BY:
Steve Allen, P.Eng., Manager Engineering Design and
Approvals (519-741-2200 x7584)
PREPARED BY:
Steve Allen, P.Eng., Manager Engineering Design and
Approvals (519-741-2200 x7584)
WARD(S) INVOLVED:
Ward # 1
DATE OF REPORT:
September 25, 2013
REPORT NO.: INS 13-020
SUBJECT:
KOLB CREEK – CLASS ENVIRONMENTAL ASSESSMENT
RECOMMENDATION:
THAT the Kolb Creek – Class Environmental Assessment Report prepared by Aquafor
Beech, dated September 30, 2013 be received; and further,
THAT a Notice of Filing be issued and the Kolb Creek Class Environmental Assessment
report be placed on the public record for 30 calendar days, in accordance with the
requirements of the Class Environmental Assessment for Remedial Flood and Erosion
Control Projects.
BACKGROUND:
The Kolb Creek watershed is located in the north eastern part of the City of Kitchener. The Kolb
Drain lies within a predominantly urban watershed with an area of approximately 455 hectares.
The creek was originally constructed as a drain in 1944 when the watershed was mostly rural.
Kolb Creek has been identified as cold water fish habitat.
A drainage study was completed in 1977 and updated in 1991 to define the effect that existing
and continued urbanization will have on the Kolb Drain. These studies concluded that
increased urbanization has created the potential for flooding on adjacent properties. The studies
also identified potential channel erosion. Improvements to the creek over the past 15 years
have included channel naturalization downstream of Smetana Drive.
In 2001, the City of Kitchener developed a Stormwater Management (SWM) Policy in order to
ensure that the most effective approach to SWM will be provided across the City. The 2001
Policy identified Kolb Creek as first priority for stormwater management and stream restoration
within the City of Kitchener due to the effects of urbanization impacting the watercourse.
The increased urbanization within the Kolb Creek drainage area and presences of undersized
culverts and crossings along the watercourse has created a potential for flooding on adjacent
properties and the potential for erosion. The downstream portion of the channel is tightly
confined between private properties, and contains a series of abrupt alignment changes with
hardened bed and banks. A portion of the study reach is channelized and even flows beneath a
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parking lot and building upstream of the Natchez Rd. crossing. The purpose of this Class EA
and preliminary design is to generate and evaluate a series of alternatives to improve the
flooding issues found within the Kolb creek system while considering environmental and aquatic
improvements.
Portions of Kolb Creek are confined to a narrow right of way, while other portions are contained
in a closed pipe system, a portion of which is located on private property.
The primary objective of the study is to determine a preferred alternative to alleviate local
flooding issues on the portion of Kolb Creek extending from Matthew St. to the existing SWM
facility east of Manchester Rd. The study will also evaluate the opportunities to retrofit an
existing stormwater management (SWM) facility within Forfar Park to improve water quality
within Kolb Creek. The study area is depicted in Figure 1.
Figure 1 – Kolb Creek Study Area
REPORT:
The objective of the study is to determine a preferred alternative to alleviate local flooding
issues on the portion of Kolb Creek extending from Matthew St. to the existing SWM facility east
of Manchester Rd. The study will also evaluate the opportunities to retrofit the existing
stormwater management (SWM) facility within Forfar Park to improve water quality within Kolb
Creek.
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Six alternatives to address the flooding problem along Kolb Creek were identified and are
described as follows:
Alternative 1 – Do Nothing
Kolb Creek remains in its current state and alignment.
Alternative 2 – Overflow Sewer along Rothsay Avenue
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This option involves the diversion of flows above approximately 7.5 m (1-in-5 year event) to be
conveyed along the north side of Rothsay Avenue within a subsurface circular pipe or box
culvert (approximately 300m in length). A new outlet would be required upstream of the existing
pedestrian bridge. All works are to be completed within City lands.
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Alternative 3 – Increase Existing Capacity
This option involves increasing the existing stream capacity through replacement of the Rothsay
Avenue culvert, ‘boring and jacking’ beneath 1263-1271 Victoria Street N. building to widen the
culvert (approximately 8 times the existing width of 2.6m to ultimate width of 20.8m),
construction of a new wider crossing along Natchez Road and increasing channel width east of
the Natchez Road crossing to upstream of the existing pedestrian bridge. Acquisition of one
private property and removal of one existing building is required. Works are required on private
property and City lands.
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Alternative 4 – Reroute Stream along Rothsay Avenue
This option involves the realignment of Kolb Creek adjacent to Rothsay Avenue by extending
the downstream easement along Rothsay Avenue up to and including the replacement of the
Rothsay Avenue culvert. Portions of the existing channel would be filled-in and the box culvert
beneath 1263-1271 Victoria Street N. building and the Natchez Road crossing would be
decommissioned. Works are required on private property and City lands. Acquisition of two
private properties and a portion of one property which fronts Rothsay Avenue would be
required. The removal of three existing buildings and establishment of a new outlet to the
existing 600mm storm sewer would be required.
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Alternative 5 – Reroute Stream between buildings
This option involves the realignment of Kolb Creek along Rothsay Avenue between existing
buildings. Portions of the existing channel would be filled-in and the box culvert beneath 1263-
1271 Victoria St. N and Natchez Road crossing would be decommissioned. Works required
would be conducted on private property and City lands. Acquisition of one private property and
a portion of one property which fronts Rothsay Avenue would be required as well as the removal
of two existing buildings and establishment of a new outlet to the existing 600mm storm sewer.
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Alternative 6 - Reroute Entire Stream within Sub-surface Sewer along Rothsay Avenue
This option involves the diversion of all flows along the north side of Rothsay Avenue within a
circular pipe or box culvert (approximately 300m in length). A new outlet would be required
upstream of the existing pedestrian bridge. All works would be completed within City lands.
Conflict with an existing 600mm diameter storm pipe would require its relocation. Conservation
Authority and Department of Fisheries and Oceans (DFO) approvals may be difficult due to the
loss of open channel.
Feasibility Screening
The Alternatives were assessed using a two (2) phase process:
1. Feasibility Screening - used to evaluate and identify alternatives to be carried forward
2.Detailed evaluation using twenty-three (23) criteria within the four (4) main
environmental assessment categories including Physical/Natural Environment,Social,
Economic and Technical/Engineering considerations.
The feasibility screening is used to identify alternatives that are more likely to be implementable
and only carry those through to the second phase, detailed assessment, and to eliminate
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alternatives that for various reasons would not be feasible to implement. The feasibility of each
alternative was reviewed in terms of:
Ability to meet study objectives (to what it extent does it fix the problem?)
Technical & Physical Feasibility (how easy is it to implement?)
Estimated Costs (how expensive?)
Landowner Acceptance (do we have buy-in from affected properties?)
Municipal/ Agency Acceptance (will regulatory agencies grant approvals?)
Environmental Impacts (what are the benefits to the environment?)
As a result of the Feasibility Screening the following alternatives were removed from the
detailed evaluation.
Alternative 3 – Increase Existing Capacity -
not carried forward due to high risk
and lack of technical feasibility.
Alternative 6 - Reroute Entire Stream within Sub-surface Sewer along Rothsay Ave. -
not
carried forward due to anticipated lack of agency support and feasibility.
The remaining alternatives were evaluated with a consistent methodology. The four evaluation
criteria (technical, economic, environmental and social) have been used to allow an alternative-
to-alternative comparison
Preferred Alternative – Kolb Creek Flooding and Erosion
To select a preferred alternative, alternatives 1, 2, 4 and 5 were evaluated using the criteria
listed in the table below.
Environmental Criteria
Ease of Implementation
Technical/Engineering
Agency and Municipality Acceptance
Considerations
Policy/Bylaw Requirements
Technical Feasibility
Natural/Physical
Potential Aquatic Habitat Benefit
Environment
((a).water temperature, (b). fish
Considerations
passage)
Potential to reduce erosion ((a).public
lands, (b). private lands)
Potential to Reduce Streambank & Bed
Erosion
Potential to Reduce Flooding
Potential to Enhance Groundwater
Potential to Improve Terrestrial Habitat
Integration with Existing Environment
Social/ Cultural
Aesthetic / Recreation
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Considerations
Landowner Acceptance
Potential Increase in Property Value
Compatibility with Adjacent Land Use
Community Disruption
Economic Considerations
Construction Costs
Long-term Operation & Maintenance
Infrastructure Protection
Through the evaluation of the alternatives using these criteria, the preferred alternative is
Alternative 2 – Overflow sewer along Rothsay Avenue.
Pond 6 Retrofit – Preferred Alternative
The study also evaluated the opportunities to retrofit an existing stormwater management
(SWM) facility within Forfar Park to improve water quality within Kolb Creek. The pond was
evaluated in 2010 under a schedule “A” Environmental Assessment. At the time of the study, it
was determined that in order to provide an appropriate solution to the pond retrofit, additional
land beyond the pond’s existing footprint (but still within the park) would be required. The
expansion of this pond triggers a schedule “B” EA. Due to the fact that the pond is upstream
and connected directly to the Kolb Creek study area, it was therefore completed as part of the
Kolb Creek study.
Following the Municipal Class Environmental Assessment process, the alternative solutions
developed to fulfill the study objectives and identified problem are evaluated using a set of
evaluation criteria. The Pond 6 Retrofit Alternatives were assessed using a detailed evaluation
process made up of eighteen (18) criteria within the four (4) main environmental assessment
categories including Physical/Natural Environment, Social, Economic and
Technical/Engineering considerations.
Four alternatives for the retrofit of Pond 6 were evaluated:
• Alternative No.1 – Do Nothing
• Alternative No.2 – Wet Pond
• Alternative No.3 – Wetland
• Alternative No.4 – Hybrid (wet pond/wetland)
Alternative No. 3 – Wetland
The preferred alternative for Pond 6 is
This alternative enhances the water quality of the Kolb Creek watershed by utilizing the existing
stormwater management pond within Forfar Park, and expanding it to include a wetland
between the inlet and outlet. The pond is characterized by a small forebay for settlement at the
inlet and a wetland consisting of wetland plants and “micro-pool” of slighty deeper water to
enhance the diversity of habitat.
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Conceptual Layout of Pond 6 Wetland
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Example of Wetland Retrofit
IMPLEMENTATION:
It is anticipated that the implementation of the recommended alternatives will be completed
during the 2015 construction season, subject to funding and council approval
COMMUNITY ENGAGEMENT:
Two Public Information Centres (PIC) were held (February 5, 2013 and July 12, 2013). The
public, agencies, stakeholders, interested and affected parties were provided with an
opportunity to review and comment on the study findings including preferred alternative, along
with the other alternatives considered. The direct mail-outs, along with the newspaper
advertisement advising the public and property owners of the project and the Public Information
Centre, provided a project overview, as well as contact names and information for those
interested. Furthermore there were many project meetings with Grand River Conservation
Authority (GRCA) to co-operatively select the preferred alternatives. The preferred alternative
was presented to the City’s Environmental Committee on September 19, 2013.
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ALIGNMENT WITH CITY OF KITCHENER STRATEGIC PLAN:
Community Priority - Environment
“Continue to show leadership in the development of an environmentally sustainable community.”
The City continues to ensure effective implementation of the stormwater management facilities
in a sustainable and optimized manner in order to protect the environment and source water.
FINANCIAL IMPLICATIONS:
The anticipated cost for implementing the preferred alternatives are:
Kolb Creek – Alternative 2 – Overflow sewer along Rothsay: $2,500,000 (Class B)
Pond 6 Retrofit: $500,000 – (Class B)
The implementation of the preferred alternative for the Kolb Creek flooding is included in the
City’s capital budget and is funded approximately 88% from the Stormwater Utility and 12%
from Development Charges. The funding is currently available in 2015.
The implementation of the preferred alternative for Pond 6 is to be funded through the City’s
Stormwater Management Pond Retrofit Program which is an annual program and included in
the City’s capital budget.
ACKNOWLEDGED BY:
Pauline Houston, Deputy CAO
Infrastructure Services Department
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