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1. JOCK RIVER REACH 1 SUBWATERSHED STUDY AND BARRHAVEN
SOUTH MASTER SERVICING STUDY ÉTUDE SUR LE SOUS-BASSIN
HYDROGRAPHIQUE DU TRONÇON 1 DE LA RIVIÈRE JOCK ET ÉTUDE SUR LE PLAN DIRECTEUR
DE VIABILISATION DE BARRHAVEN SUD |
Committee recommendationS
That Council:
1. Approve the Jock
River Reach 1 Subwatershed Study (Stantec, June 2007).
2. Approve the Barrhaven
South Conceptual Fish Habitat Compensation Plan (Niblett, November 2006) and
the use of City land known as 3300 Cedarview Road for the creation of a new
fisheries habitat area.
3. Approve the
recommended projects identified in the Barrhaven South Master Servicing Study
prepared by Stantec, illustrated in Document 6, in accordance with the
requirements of the Ontario Environmental Assessment Act.
4. Direct Planning,
Transit and Environment staff to finalize the Barrhaven South Master Servicing
Study and proceed with the 30-day public review period, in accordance with the
Ontario Environmental Assessment Act and as a prelude to the initiation of the
detailed design.
RecommandationS du Comité
Que le Conseil :
1. Approuve l’étude sur le sous-bassin
hydrographique du tronçon 1 de la rivière Jock (Stantec, juin 2007);
2. Approuve le Plan de compensation
conceptuel sur l’habitat du poisson de Barrhaven Sud (Niblett, novembre 2006)
et l’utilisation des propriétés de la Ville situées au 3300, chemin Cedarview,
pour la création d’une nouvelle zone d’habitat du poisson;
3. Approuve les projets recommandés
indiqués dans l’étude sur le Plan directeur de viabilisation de Barrhaven Sud
préparée par Stantec et illustrée dans le Document 6, conformément aux
exigences de la Loi sur l’évaluation environnementale de l’Ontario;
4. Demande au personnel d’Urbanisme,
Transport en commun et Environnement de finaliser l’étude sur le Plan directeur
de viabilisation de Barrhaven Sud et d’aller de l’avant avec la période
d’examen public de 30 jours, conformément à la Loi sur l’évaluation
environnementale de l’Ontario et à titre de prélude au lancement de la
conception détaillée.
Documentation
1.
Deputy
City Manager's report Planning, Transit
and the Environment dated
11 June 2007 (ACS2007-PTE-POL-0004).
Report
to/Rapport au :
Planning and Environment Committee
Comité de l'urbanisme et de
l'environnement
and Council / et au Conseil
11 June 2007 / le 11 juin 2007
Submitted by/Soumis par : Nancy Schepers, Deputy City Manager /
Directrice municipale adjointe,
Planning, Transit and Environment/Service de l'urbanisme, du transport
en commun
Contact
Person/Personne ressource : John L. Moser, Director/Directeur,
Planning Branch/Direction de l’urbanisme
(613) 580-2424 x 28869, John L.
Moser@ottawa.ca
REPORT RECOMMENDATION
That Planning and Environment Committee
recommend City Council:
1. Approve
the Jock River Reach 1 Subwatershed Study (Stantec, June 2007).
2. Approve the Barrhaven South Conceptual Fish Habitat Compensation Plan (Niblett, November 2006) and the use of City land known as 3300 Cedarview Road for the creation of a new fisheries habitat area.
3. Approve the recommended projects identified in the Barrhaven South Master Servicing Study prepared by Stantec, illustrated in Document 6, in accordance with the requirements of the Ontario Environmental Assessment Act.
4. Direct Planning, Transit and Environment staff to finalize the Barrhaven South Master Servicing Study and proceed with the 30-day public review period, in accordance with the Ontario Environmental Assessment Act and as a prelude to the initiation of the detailed design.
RECOMMANDATION DU RAPPORT
Que le Comité de l’urbanisme et de
l’environnement recommande au Conseil municipal :
1. d’approuver
l’étude sur le sous-bassin hydrographique du tronçon 1 de la rivière Jock
(Stantec, juin 2007);
2. d’approuver
le Plan de compensation conceptuel sur l’habitat du poisson de Barrhaven Sud
(Niblett, novembre 2006) et l’utilisation des propriétés de la Ville situées au
3300, chemin Cedarview, pour la création d’une nouvelle zone d’habitat du
poisson;
3. d’approuver
les projets recommandés indiqués dans l’étude sur le Plan directeur de
viabilisation de Barrhaven Sud préparée par Stantec et illustrée dans le
Document 6, conformément aux exigences de la Loi sur l’évaluation
environnementale de l’Ontario;
4. de
demander au personnel d’Urbanisme, Transport en commun et Environnement de
finaliser l’étude sur le Plan directeur de viabilisation de Barrhaven Sud et
d’aller de l’avant avec la période d’examen public de 30 jours, conformément à
la Loi sur l’évaluation environnementale de l’Ontario et à titre de prélude au
lancement de la conception détaillée.
EXECUTIVE SUMMARY
Assumptions and Analysis:
The
Barrhaven South Community Design Plan (CDP) was approved by City Council on
June 28, 2006. One of the approved
recommendations directed staff to bring forward for approval the required
Subwatershed Study for the Jock River Reach 1, the Conceptual Fish Habitat
Compensation Plan, and the Master Servicing Study. These supporting studies
have now been completed and are the subject of this report for approval.
The
City and the principal landowners within Barrhaven South undertook the
following technical studies, as co-proponents, following the Class
Environmental Assessment (EA) process in support of the Barrhaven South
Community Design Plan:
· Jock
River Reach 1 Subwatershed Study (June 2007)– Stantec Consulting Ltd., Niblett
Environmental Associates Inc., Parish Geomorphic
· Barrhaven
South Conceptual Fish Habitat Compensation Plan (November 2006) – Niblett
Environmental Associates Inc.
· Barrhaven
South Master Servicing Study - Stantec Consulting Ltd.
The
subwatershed study has developed a stormwater management and natural
environment plan for north of the Jock River, south of the Jock River and the
Jock River Corridor to assist with future studies and development requirements.
The
Barrhaven South Conceptual Fish Habitat Compensation Plan (CFCP) identifies
fish habitat restoration and enhancement measures to address the fish habitat
losses associated with the development of Barrhaven South. The Barrhaven South Master Servicing Study
has identified an internal servicing scheme for water, sanitary, storm drainage
and stormwater management servicing that supports the land uses and development
densities approved through the Barrhaven South Community Design Plan. The following infrastructure projects have
been recommended for the Barrhaven South development area following the Class
EA process for Schedule B undertakings:
· Wastewater
collection system
· Water
distribution system
· Enclosure/partial
enclosure of four watercourses (Todd, East Clarke, West Clarke and Corrigan
municipal drains/tributaries)
· Construction of five stormwater detention facilities and associated storm drainage collection systems, including:
o Corrigan
SWM Pond and associated storm sewers (Schedule B)
o Greenbank
SWM Pond and associated storm sewers (Schedule B)
o Todd
SWM Pond and associated storm sewers (Schedule B)
o Clarke
SWM Pond and associated storm sewers (Schedule B)
o Cedarview
SWM Pond and associated storm sewers (Schedule B)
The
Master Servicing Study has also identified constraints that will influence the
storm drainage servicing of the site.
Subsurface investigations originally prepared in support of Master
Planning identified soil conditions (compressible silty clays) over parts of
the development area which will limit the extent to which the site may be
raised or require considerable engineering measures to achieve grade
raise. A servicing plan was prepared
based on a grade raise not to exceed 1.5 m.
Further detailed geotechnical investigations during subdivision design
indicated that soils at some locations were poorer than anticipated and the
preliminary grading plan in support of servicing design was revised to a grade
raise not to exceed 1.0 m. Engineering
measures including pre-loading or surcharging may be required to safely
accommodate the grade raises proposed at detailed design stage.
Given
the low lying areas in the northern portion of the study area and the grade
raise restrictions noted above, much of the storm sewer system will have
minimal cover and a portion of the system will be subject to permanent standing
water. These conditions will preclude
the use of standard depth basements over a portion of the study area.
The
approval of these technical studies will facilitate the processing and approval
of development applications in the area.
Financial Implications:
The
majority of projects identified in the technical studies will be financed
through Development Charges, developers or existing programs through Council’s
budgetary approval process.
Site
constraints arising from soil conditions that limit grade raises in combination
with low lying areas over a large portion of the site will result in permanent
standing water in a significant portion of the storm sewer system.
This will result in signficantly increased costs to the City to own, operate and maintain the affected sewers due to the need for regular pumping to draw down the sewers and/or other measures to manage the increased potential for sedimentation in the pipes.
Public Consultation/Input:
The
consultation program fulfilled the consultation requirements specified in the
Municipal Engineers Association Class Environmental Assessment document for
Schedule B projects. A total of four
open houses/ workshops were conducted at key project milestones. Individual and collective meetings with
other City staff, Rideau Valley Conservation Authority, and provincial and
federal agencies to discuss technical requirements and comments were held on
numerous occasions throughout the development of both studies.
The Barrhaven South Master Servicing Study will be finalized after City Council approves the recommended projects (Recommendation 3). Notices of Completion will be published for both the Subwatershed Study and Master Servicing Study notifying the public of the availability of the reports and the 30-day public review period.
RÉSUMÉ
Hypothèses et analyse :
Le 28 juin 2006, le Conseil municipal
a approuvé le Plan de conception communautaire (PCC) de Barrhaven Sud. Dans une
des recommandations approuvées, on demandait au personnel de présenter pour
fins d’approbation l’étude sur le sous-bassin hydrographique requise pour le
tronçon 1 de la rivière Jock, le Plan de compensation conceptuel sur l’habitat
du poisson et l’étude sur le Plan directeur de viabilisation. Ces études
complémentaires sont maintenant terminées et font l’objet du présent rapport
qui doit être approuvé.
La Ville et les principaux propriétaires de
Barrhaven Sud ont entrepris les études techniques suivantes, à titre de
coproposants, à la suite du processus d’évaluation environnementale (ÉE) de
portée générale à l’appui du Plan de conception communautaire de Barrhaven
Sud :
. Étude
sur le sous-bassin hydrographique du tronçon 1 de la rivière Jock
(juin 2007) – Stantec Consulting Ltd., Niblett Environmental
Associates Inc., Parish Geomorphic;
. Plan
de compensation conceptuel sur l’habitat du poisson de Barrhaven Sud
(novembre 2007) – Niblett Environmental Associates Inc.;
. Étude
sur le Plan directeur de viabilisation de Barrhaven Sud – Stantec
Consulting Ltd.
Dans le cadre de l’étude sur le sous-bassin
hdrographique, on a établi un plan d’environnement naturel et de gestion des
eaux pluviales pour le nord de la rivière Jock, le sud de la rivière Jock et le
corridor de la rivière Jock pour aider aux études futures et aux besoins
d’aménagement. Le Plan de compensation conceptuel sur l’habitat du poisson de
Barrhaven Sud soulève les mesures d’amélioration et de restauration de
l’habitat du poisson à prendre pour remédier aux pertes de l’habitat du poisson
associées à l’aménagement de Barrhaven Sud.
Dans le cadre de l’étude sur le Plan directeur
de viabilisation de Barrhaven Sud, on a déterminé un plan de service interne
pour les services publics d’eau, d’égouts sanitaires et pluviaux et de gestion
des eaux pluviales, lequel appuie l’utilisation des terrains et les espaces
d’aménagement approuvés par le Plan de conception communautaire de Barrhaven
Sud. Les projets d’infrastructure suivants ont été recommandés pour la zone de
développement de Barrhaven Sud à la suite du processus d’ÉE de portée générale
pour les initiatives de l’annexe B :
. réseau
de collecte des eaux usées;
. réseau
de distribution d’eau;
. isolement/isolement
partiel de quatre cours d’eau (drains municipaux/affluents de Corrigan, Todd,
East Clarke, West Clarke);
. construction
de trois installations de retenue des eaux pluviales et de réseaux connexes de
collecte et de drainage des eaux pluviales, y compris :
○
le
bassin de GEP Corrigan et les égouts pluviaux connexes (annexe B),
○
le
bassin de GEP Greenbank et les égouts pluviaux connexes (annexe B),
○
le
bassin de GEP Todd et les égouts pluviaux connexes (annexe B),
○
le
bassin de GEP Clarke et les égouts pluviaux connexes (annexe B),
○
le
bassin de GEP Cedarview et les égouts pluviaux connexes (annexe B).
Dans l’étude sur le Plan directeur de
viabilisation, on a également déterminé les contraintes qui influenceront les
services publics de drainage pluvial du site. Les études souterraines réalisées
à l’origine en complément du plan directeur ont révélé que les conditions du
sol (argile limoneuse compressible) de certaines parties du secteur
d’aménagement limitent la possibilité de soulever l’emplacement ou nécessitent
des mesures techniques considérables pour un soulèvement. Un plan de
viabilisation a été préparé à partir d’une élévation n’excédant pas
1,5 mètre. D’autres études géotechniques détaillées, effectuées pendant la
conception détaillée, ont révélé que, à certains endroits, le sol était plus
pauvre que prévu et le plan préliminaire de nivellement appuyant la conception
de viabilisation a été révisé pour que le soulèvement n’excède pas 1,0 m. Les
mesures techniques, comme celles de préchargement ou de surchargement, peuvent
s’avérer nécessaires pour réaliser en toute sécurité l’élévation proposée du
niveau lors de l’étape de conception détaillée.
Étant donné les régions basses dans la partie
nord de la zone d’étude et les restrictions quant à l’élévation du niveau
susmentionnées, le réseau d’égouts pluviaux sera en grande partie peu couvert
et une partie du réseau sera assujettie à des eaux dormantes permanentes. Ces
conditions empêcheront l’utilisation des sous-sols de profondeur standard dans
une importante partie de la zone d’étude.
L’approbation de ces études techniques
facilitera le traitement et l’approbation des demandes d’aménagement dans le
secteur.
Répercussions financières :
La majorité des projets soulevés dans les
études techniques seront financés par les redevances d’aménagement, les
promoteurs ou les programmes actuels, conformément au processus d’approbation
des budgets du Conseil.
Les contraintes du site découlant des
conditions du sol qui limitent les élévations du niveau en combinaison avec les
régions basses sur une grande partie du site auront pour conséquence la
présence d’eaux dormantes permanentes dans une importante partie du réseau
d’égouts pluviaux. Cela entraînera une augmentation considérable des coûts à la
Ville pour acquérir, faire fonctionner et entretenir les égouts touchés en
raison du besoin d’un pompage régulier pour abaisser le niveau des égouts et/ou
d’autres mesures pour gérer la possibilité accrue d’une sédimentation dans les
tuyaux.
Consultation publique / commentaires
:
Le programme de consultation a répondu aux
besoins de consultation précisés dans le document de l’évaluation
environnementale de portée générale de la Municipal Engineers Association pour
les projets de l’annexe B. Au total, quatre consultations publiques/ateliers
ont été tenus à des étapes marquantes du projet. On a organisé à plusieurs
occasions tout au long du développement des études des réunions individuelles
et collectives avec d’autres membres du personnel de la Ville, l’Office de
protection de la nature de la vallée Rideau et des organismes provinciaux et
fédéraux afin de discuter des exigences techniques et des commentaires reçus.
L’étude sur le Plan directeur de viabilisation
de Barrhaven Sud sera finalisée une fois que le Conseil municipal aura approuvé
les projets recommandés (Recommandation 3). Des avis d’achèvement seront
publiés pour l’étude sur le sous-bassin hydrographique et l’étude sur le Plan
directeur de viabilisation informant le public de la disponibilité des rapports
et de la période d’examen public de 30 jours.
BACKGROUND
Barrhaven
South is an area of approximately 500 hectares in size located in the southern
end of the urban area of Ottawa, as illustrated in Document 1. The Barrhaven South study area is defined by
the Jock River to the north, Highway 416 to the west, Jockvale Road and
Greenbank Road to the east, and the urban area boundary to the south. Barrhaven South is west of, and adjacent to,
the developing community of Stonebridge, and is south of the South Nepean Town
Centre. In January 2005, a consultant
team, working on behalf of the principal landowners within the Barrhaven South
boundary, in concert with the Planning, Transit and Environment Department,
initiated the Barrhaven South Community Design Plan (CDP). As part of the development of the CDP, the
Jock River Reach 1 subwatershed, transportation master plan and master
servicing studies were undertaken to identify the environmental, roadway,
transit and infrastructure servicing requirements to guide and support the
preferred land use plan. All of these
technical studies followed the Municipal Engineers Association (MEA) Class
Environmental Assessment process.
The
Barrhaven South Community Design Plan (CDP) and Transportation Master Plan were
completed and approved by Council in June 2006
(http://ottawa.ca/calendar/ottawa/
citycouncil/pec/2006/06-13/ACS2006-PGM-POL-0042.htm). The subwatershed and master servicing studies were not finished
at that time. Council approved staff's
recommendation to bring forward the master servicing study, the subwatershed
study for Reach 1 of the Jock River and conceptual fish compensation plan for
Council approval.
Council
approved Recommendation 4 of the Barrhaven South Community Design Plan Report
that directed Legal Services to bring forward the Barrhaven South draft
Official Plan Amendment implementing by-law to City Council for approval once
the three studies had received City Council approval.
The
Jock River Reach 1 Subwatershed Study and Barrhaven South Master Servicing Study
report was brought forward for approval to the February 13, 2007 Planning and
Environment Committee meeting and approved.
At the February 23 meeting of Council, a deferral motion moved by
Councillor Harder and seconded by Councillor Desroches was approved that
stated:
"WHEREAS
staff require further time to consider new servicing proposals received from
landowners in Barrhaven South CDP area that could amend the Jock River Reach 1
Subwatershed Study and Barrhaven South Master Servicing Study;
THEREFORE
BE IT RESOLVED that Item 13 - PEC Report 3-B(ACS2007-PTE-POL-004 Jock River
Reach 1 Subwatershed Study and Barrhaven South Master Servicing Study) be
deferred and, should staff determine that changes are required to the studies,
it be brought forward to Planning and Environment Committee."
Since
this time, City staff and their consultant Stantec Consulting have considered
the new soils information presented by landowners as it relates to grade raise
limitations and its impact on storm drainage and stormwater management
requirements. Based on this technical
review and analysis, the preferred stormwater management solution for Barrhaven
South has been modified by the addition of two stormwater management ponds
which will serve to reduce the maximum required grade raises across the areas
of the site most constrained by soils conditions - generally the northern
portion of the development area. The
Jock River Reach One Subwatershed Study and Barrhaven South Master Servicing
Studies have been revised to document and present the modified stormwater
management option.
The Jock River Reach 1 Subwatershed Study and Barrhaven South Conceptual Fish Habitat Compensation Plan are now complete and finalized (Document 2, distributed under separate cover) and as per Recommendations 1 and 2 of this report, approval of these documents are recommended. As per Recommendation 3 of this report, staff recommends approval of the wastewater, water, storm drainage and stormwater management projects identified through the final Barrhaven South Master Servicing Study (Document 6). The approval of these technical studies will allow the Official Plan Amendment to proceed to Council, facilitating the processing and approval of development applications in the Barrhaven South area. The purpose of this report is to provide a summary of the study process that lead to the environmental and infrastructure servicing recommendations.
DISCUSSION
The
Jock River Reach 1 Subwatershed Study and Barrhaven South Master Servicing
Study followed an integrated planning approach such that the environmental and
preliminary servicing requirements were identified and integrated into the
development of the preferred land use plan for Barrhaven South.
Detailed
analysis was then undertaken based on the preferred concept plan to
sufficiently define the environmental and infrastructure servicing requirements
consistent with applicable policies, regulations and engineering
standards. Although separate documents
have been produced, the technical studies were planned and coordinated as an
integrated master planning exercise.
The
City and the principal landowners within Barrhaven South are co-proponents for
the required Class Environmental Assessments.
The subwatershed and master servicing studies have completed Phases 1
and 2 of the MEA Class Environmental Assessment process following the Master
Plan approach. The subwatershed study
followed “Approach #1” of the Master Planning approach whereby a broad level of
assessment has been undertaken such that projects identified would require
further assessment under the Class EA.
The Master Servicing Study followed “Approach #2” whereby the level of
assessment, consultation and documentation are sufficient to fulfill the
requirements for Schedule B projects.
Following the posting of the Notice of Completion and the conclusion of
the 30-day public review period, all Class EA requirements will have been met
and the identified projects may proceed to detailed design and
construction. For the area north of the
Jock River, the conceptual stormwater management option identified in the
subwatershed study would be subject to completing the EA requirements and
approvals in the future.
A
summary of the study methodology, analysis and recommendations associated with
the three technical studies is provided below.
Jock
River Reach 1 Subwatershed Study
The
Barrhaven South community falls within Reach 1 of the Jock River subwatershed
area. The subwatershed boundary is
larger than the CDP area as it follows a natural drainage area boundary. Document 1, Study Area Figure, illustrates
the subwatershed boundary that includes lands north of the Jock River within
the existing Barrhaven community and adjacent vacant urban lands, east of
Highway 416. The subwatershed has a
total area of approximately 2,300 hectares, one half of which is already
developed. The majority of the
subwatershed is in the urban area with approximately 711 ha of vacant land
located north of the Jock River and approximately 360 ha vacant land situated
south of the Jock River.
The
Jock River Reach 1 subwatershed study provides the environmental and conceptual
stormwater management requirements for the Barrhaven South community and the
undeveloped urban lands north of the Jock River, straddling Strandherd
Drive. The management strategy aims to
protect, restore or enhance the significant natural features and functions
identified in the subwatershed while accommodating development, over the
long-term.
As
part of the subwatershed study, a Conceptual Fish Habitat Compensation Plan
(CFCP) has been prepared to identify fish habitat restoration and enhancement
measures to address the fish habitat losses associated with the development of
Barrhaven South.
The
Jock River Reach 1 subwatershed planning process was comprised of four main
phases: 1) Characterization of Existing Environmental Conditions; 2)
Establishment of Subwatershed Goals and Objectives; 3) Development of the
Preferred Management Strategy; and, 4) Implementation Strategy. Reach One of the Jock River falls within the
Rideau River watershed.
The Council approved Lower Rideau River Watershed Strategy (http://ottawa.ca/calendar/ottawa/ citycouncil/pec/2006/10-24/ACS2006-PGM-POL-0080.htm) was a guiding document in the development of the subwatershed plan. The main phases and outcome of the subwatershed process are summarized below.
Existing Environment Conditions
The
existing natural resources within the subwatershed were identified and assessed
to determine significant features and functions within the study area. Investigations were conducted in the areas
of hydrology, terrestrial, aquatic, water quality, fluvial geomorphology, and
hydrogeologic resources. The level of
detail differed for lands north and south of the Jock River, in that more
detailed field investigations and analysis were undertaken for the lands south
of the Jock River in association with the Barrhaven South Community Design
Plan.
Document
3, Environmental Constraints and Opportunities map and key findings, illustrates
the important natural features within the subwatershed, such as woodlands and
watercourses. Key environmental
findings are highlighted below and summarized in Document 3:
Tributaries:
· North
of the Jock River, the main tributaries are O’Keefe Drain, Foster Ditch and
Fraser Clarke Drain.
· South
of the Jock River, the main tributaries are the West Clarke Drain, East Clarke
Drain, Todd Drain and Corrigan tributary.
· All tributaries to the Jock River support fisheries and are considered fish habitat.
· The
tributaries provide only a highly seasonal and marginal fish habitat for a
handful of warm water tolerant fish species.
Terrestrial
Resources:
· A
total of 28 woodlands exist in the subwatershed. A total of nine woodlands were identified as significant
consistent with the findings of the Urban Natural Areas Environmental
Evaluation Study. These include Urban
Natural Areas #49 (W7), #50 (W44), #57 (W1 W2), #58 (W10), #60 (W43), #183
(W50).
· Significant
species reported or observed include one federal (butternut), one provincial
(greater redhorse fish species) and fourteen regionally rare species.
Jock
River:
· Jock
River is highly productive fisheries resource that contains healthy populations
of naturally reproducing game fish such as muskellunge.
· A
number of important and/or critical fish habitat areas within the main stem of
the Jock River have been identified within Reach 1.
· Jock
River water quality is highly impaired and does not meet provincial water
quality criteria.
· The
Jock River is classified as a Policy 2 watercourse for phosphorus, which
requires a net reduction in phosphorus loadings to the river.
· Through
the fluvial geomorphology investigation, the meander belt width was determined
for the Jock River corridor representing the maximum lateral extent of the
channel over time. Meander belt is
considered a hazard constraint that needs to be considered in establishing
development setbacks from the river.
The
environmental constraints and opportunities map was used to develop land use
concept alternatives for Barrhaven South.
The Jock River corridor, its floodplain, two tributaries and the two
significant woodlands were identified for protection. The environmental features were used to plan and integrate the
parks, open space and stormwater management facilities forming the greenspace
network for the community. Built form
and layout design were then developed in concert with the greenspace network
ensuring compatibility with natural attributes of the area.
Jock River Reach 1 Management Strategy
Evaluation and
assessment of the various natural resource components of the subwatershed were
conducted to understand and identify the important features and functions
occurring in the subwatershed. This
holistic understanding of the health and state of the subwatershed’s ecosystem
has led to the preparation of the preferred management strategy for the areas
north and south of the Jock River. The
Jock River Reach 1 management strategy consists of three main components:
Conceptual Stormwater Management Plan; Natural Environment Plan and Conceptual
Fish Habitat Compensation Plan.
Stormwater
Management Design Criteria
Following the
analysis of the existing condition of the subwatershed and a series of detailed
hydrologic assessments, the criteria for the management of urban runoff were
established. All future stormwater
management facilities within Reach 1 must comply with the stormwater management
design criteria summarized below.
Jock River:
· No quantity control
storage required for flood control purposes as the hydrograph from the
subwatershed will peak before the upstream peak in the Jock River.
· No erosion control
storage required to maintain the predevelopment in-stream erosion condition.
· Quality control storage as per the Ministry
of Environment Enhanced Treatment (80% TSS removal), following the integrated
SWM approach recommended in the Lower Rideau Watershed Strategy.
North
of the Jock River - criteria for stormwater management facilities:
· Quantity control storage as required
to meet constraints within existing channels and/or at existing crossings
(quantity control/level of control to be determined through further detailed
study).
· Erosion control storage as required
to maintain stability and geomorphic function of the existing tributaries, as
determined through further detailed study.
· Quality control storage as per the
Ministry of Environment Enhanced Treatment (80% TSS removal).
· All stormwater management facility
outlets will be designed to augment low flows to the extent possible.
South of the Jock
River - criteria for stormwater management facilities:
· Quantity control storage as required
by the capacity of rehabilitated tributaries.
· No erosion control storage required;
rehabilitated tributaries to be designed to withstand the erosive impulse of
stormwater runoff.
· Quality control storage as per the
Ministry of Environment enhanced level treatment (80% TSS removal).
· All stormwater management facility
outlets will be designed to augment low flows to the extent possible.
Subwatershed Water Balance:
· Implement structural infiltration
practices (e.g. infiltration trenches) in areas of suitable soil; implement
non-structural best management practices (e.g. reduced grading, disconnected
impervious areas, promotion of open space and park lands, maximizing vegetative
cover) elsewhere in the system to reduce magnitude of runoff volume.
Additional
analysis was conducted to the satisfaction of the Ministry of Environment that
demonstrated the combination of urbanization and stormwater treatment will
reduce net loading of phosphorus to the Jock River.
Evaluation of
Stormwater Management Options
A number of
stormwater management options were established for north and south of the Jock
River. For north of the Jock River,
three stormwater management options were developed for the future urban areas
west of Cedarview Road, associated with the O’Keefe Drain and Foster Ditch
drainage areas. For south of the Jock
River, five alternative stormwater management options were developed to service
the Barrhaven South community. All of
the alternatives were evaluated based on criteria established for the study and
presented to the public: financial (40%);
fish and aquatic life (25%); terrestrial vegetation and communities (15%);
social/community (20%). Based on the
evaluation of alternatives, a preferred conceptual stormwater management
solution was selected for both north and south of the Jock River. A three-pond configuration, Option 2, as
illustrated in Document 5, is proposed to provide stormwater management for the
lands north of the Jock River. Further
detailed studies are required to confirm this conceptual stormwater management
solution.
For south of the
Jock River, a three-pond configuration was originally selected as the preferred
stormwater management solution for Barrhaven South (January 2007). Based on the more detailed geotechnical
investigations, two additional ponds have been added to the configuration in
order to limit grade raise requirements along the north face of the development
area and where soils conditions limit grade raise (Document 6, Figure ST1 -
Preferred Stormwater Management Solution).
The proposed
stormwater management system will enclose the East Clarke drain and Corrigan
tributary, and partially enclose the West Clarke and Todd drains. The remaining open drains will be realigned
and rehabilitated, improving habitat for fisheries to meet federal Fisheries
Act requirements. Additional fisheries
improvement opportunities will be explored at the detailed design stage for the
outlets from the Cedarview and Greenbank ponds. Further details on the stormwater management system and realigned
tributary corridors are contained within the Barrhaven South Master Servicing
Study. Fisheries enhancement works to
address fish habitat losses associated with the enclosure of the tributaries
are provided in the Barrhaven South Conceptual Fish Habitat Compensation Plan
(CFCP).
The area-specific
Development Charges By-law 2004-304 for stormwater management facilities and
associated drainage systems north and south of the Jock River will need to be
revised to account for the new infrastructure projects eligible for Development
Charges as identified in the subwatershed and master servicing studies.
Subwatershed Management Plan
A management plan
comprising of the preferred conceptual stormwater management plan and natural
environment plan has been developed for: 1) North of the Jock River; 2) South
of the Jock River; and, 3) the Jock River Corridor. A summary of the subwatershed's management plan recommendations
is found in Document 4. The
recommendations have been presented for each stormwater drainage area north and
south of the Jock River along with management recommendations for the Jock
River corridor system.
Implementation Strategy
For the lands within the O’Keefe Drain and Foster Ditch catchment areas
north of the Jock River, an integrated planning approach to confirm the final
stormwater and natural environment management plans will be taken. For the O’Keefe Drain, the first development
application received within the catchment area will be required to prepare an
Environmental Management Plan (EMP) in collaboration with the City and other
agencies including RVCA, MOE, MNR, and DFO as required. The EMP will need to conduct further
analyses and investigations to confirm and approve the stormwater and natural
environment management recommendations for the catchment area. For the Foster Ditch catchment area, a
drainage area study to confirm and plan the stormwater management pond and any
associated tributary works/enhancement will be undertaken by the developers in
collaboration with the City and other approval agencies.
For the retrofit
and expansion of the Kennedy-Burnett facility, detailed studies conforming to
the Municipal Class EA will be required.
The City of Ottawa will facilitate the study for the expansion and
design of the facility in accordance with the criteria and recommendations
presented in the subwatershed study.
For south of the
Jock River, the East Clarke, West Clarke and Todd municipal drains will require
abandonment as per the Drainage Act before or in conjunction with development
proceeding. These drains are entirely
contained within the urban area and all lands draining into these drains will
be urban development consistent with the Council approved Community Design
Plan.
The Barrhaven
South Master Servicing Study, as discussed later in this staff report, has
completed more detailed analysis of the recommended stormwater management
concept for Barrhaven South. The Master
Servicing Study will fulfill the Class EA requirements for the stormwater
management facilities and watercourse enclosures in Barrhaven South. The developers will conduct detailed design
of the stormwater management facilities and restored tributaries as part of the
development approval process. Tributary
enhancement and rehabilitation works must be completed in accordance with the
Conceptual Fish Habitat Compensation Plan and receive DFO and RVC authorizations. Any proposed tributary enclosure will
trigger the detailed design and construction of the fish habitat compensation
area on City lands adjacent to the existing Foster detention pond. This will be the responsibility of the
developers.
Recommendations
for the management and enhancement of the Jock River corridor will be
implemented through development approvals, City and RVCA programs and
stewardship activities. It is
anticipated that the Lower Rideau Watershed Strategy (LRWS) implementation committee
will facilitate a number of the works in collaboration with the community
groups and volunteer organizations such as Friends of the Jock River. Further detailed erosion and migration rate
analyses are required along Reach 1 and Reach 2 of the Jock River, particularly
in the vicinity of Half Moon Bay, to confirm the preliminary meander belt width
provided in the subwatershed study.
This will be the responsibility of the developer(s) as part of the
development review process.
Overall monitoring
of the health and condition of the subwatershed will be incorporated into the
Lower Rideau Watershed Strategy integrated monitoring program.
Barrhaven South
Conceptual Fish Habitat Compensation Plan
The Conceptual
Fish Habitat Compensation Plan (CFCP, Niblett 2006) was developed to address
proposed fish habitat losses associated with the development of the Barrhaven
South CDP area (Document 2, distributed under separate cover). Applying an integrated environmental and
land use planning approach, the subwatershed study recommends enclosure of the
East Clarke drain and Corrigan tributary with partial enclosure of the West
Clarke and Todd drains. These full and
partial watercourse enclosures are considered harmful alteration, disruption
and destruction of fish habitat under the federal Fisheries Act. Working with the Department of Fisheries and
Oceans, Rideau Valley Conservation Authority and the Ministry of Natural
Resources, restoration opportunities were investigated to meet the requirements
of the federal Fisheries Act and the study’s environmental objectives. Restoration opportunities along the
remaining tributaries are being proposed, applying natural channel design
principles. A new meandering, low flow
channel with be established incorporating fish habitat works such as
riffle-pool complexes. In order to meet
a net gain in fisheries and productive capacity within the Jock River system,
the creation of a new fish habitat area is being proposed on City lands adjacent
to the existing Foster detention pond, north of the Jock River, west of
Cedarview Road (refer to Document 3, Environmental Constraints and
Opportunities Map). The surface area of
the new fisheries habitat area is approximately 21,500 m2. The new habitat area will be connected to
the Jock River and be designed as spawning habitat for pike and other
species. This land is situated in the
floodplain and, as such, has very limited development or program use potential.
Real Estate
Services was consulted on the proposed use of City lands to accommodate a fish
habitat creation area. An internal and
utility circulation was undertaken for the vacant portion of City lands known
municipally as 3330 Cederview Road.
There were no requirements or comments for the lands that preclude the
creation of fish habitat on the subject property. The following comments will be considered during the detailed
design stage and associated respondents consulted.
Planning,
Environment and Infrastructure Policy Branch:
· No activity should preclude the
long-term use of the lands as public open space.
· The new habitat area should not
impede any future roadway plans for Cedarview Road. Ottawa Forest and Greenspace Advisory Committee
· It is imperative that the riparian
vegetation be retained and enhanced if it does not interfere with the fish
habitat plan.
Hydro Ottawa:
· Transformer situated on the property
owned by Hydro Ottawa.
The Department of
Fisheries and Oceans has agreed in principle to the Conceptual Fish Habitat
Compensation Plan for Barrhaven South.
The CFCP has not changed as a result of the five-pond stormwater
management solution. Fisheries
improvements associated with the additional outlets will be examined at the
detailed design stage. It will be the
responsibility of the developers to undertake the detailed design of the fish
spawning area and obtain authorization from DFO in collaboration with the
City. Any use of City land for this
purpose will have to be conducted under the authority of a lease or license
agreement, with compensation being based on market value. The City will retain ownership of the land
throughout all stages of the project and ultimately own the new fish habitat
area.
Barrhaven South
Master Servicing Study
The Barrhaven
South Master Servicing Study has been completed to identify an internal
servicing scheme for water, sanitary, storm drainage and stormwater management
servicing that supports the land uses and development densities approved
through the Barrhaven South Community Design Plan. The study will serve as a guide for the detailed design of
infrastructure to support future development applications. The principal recommendations of the master
servicing study are summarized below.
Wastewater
Servicing
The Master
Servicing Study completed analyses to consider both internal and external
wastewater servicing issues, including an assessment of existing trunk sewer
capacity and an evaluation of wasterwater servicing alternatives.
Existing Trunk
Sewer Capacity: The existing South
Nepean Collector (SNC) and West Rideau Collector (WRC) sanitary trunk sewers
service the South Urban Community (SUC) which includes Riverside South,
Manotick and Barrhaven South.
As current
development densities within both the Barrhaven South and Riverside South
communities suggest higher densities than those considered in previous
servicing studies, a capacity analysis of the SNC and WRC downstream of the
SNC’s Jock River crossing was completed to determine whether there was
sufficient capacity to accommodate the proposed densities within the Barrhaven
South CDP.
The existing trunk
sewer capacity analysis was completed making use of the City’s H2O Map sewer
model considering the build-out condition as per the current Official Plan for
all areas tributary to the collectors including Riverside South, Barrhaven
South and Manotick. Two modelling scenarios were considered:
Scenario 1: -
Existing development peak flows were calculated using parameters derived from
actual flow monitoring of the trunks while future development peak flows were
calculated using standard design parameters (parameters from monitored flows
tend to result in lower peak flows than standard design parameters).
Scenario 2: -
Existing and future development peak flows were calculated using standard
design parameters.
Assuming buildout
conditions, the modeling results for the two scenarios predict a range of
hydraulic grade line (HGL) elevations depending on the flow parameters used to
generate existing and future flows.
Results are summarized as follows:
Scenario 1:
Monitored Parameters for Existing Development and Design Parameters for Future
Development
· Primarily free-flow conditions, with
localized areas of minor surcharge in the WRC and SNC.
· No backwater impacts on the Riverside
South and Barrhaven South communities.
Scenario 2: Design
Parameters for Existing and Future Development
· Severe surcharge along the WRC and
SNC.
· Backwater impacts on the Riverside
South community with potential impacts on the Barrhaven South community.
· Potential for surface spills along
the WRC unless maintenance holes are sealed.
Consistent with
the findings of other recent evaluations (e.g., Riverside South Master
Servicing Study), the above analyses demonstrate that the current proposed
level of development within the SUC could potentially lead to surcharge levels
along the WRC if flow contributions predicted by design parameters are
realized. However, flows derived from
observed (monitored) flow conditions for existing development indicate that
currently proposed levels of development could be serviced without causing
critical levels of surcharge.
The capacity of
the WRC is approximately 3000L/s. The
existing peak flow in the WRC, calculated using design flow parameters, is
1540L/s. Therefore, the residual peak
flow is estimated at 1460L/s. Assuming
a linear growth trend between 2006 and 2021, the residual capacity (1460 L/s)
would be used up by the year 2017. This flow condition would be equivalent to
an additional 100,594 persons, 62,695 employees and 2040ha of development in the
WRC catchment area.
This represents an
approximate ten year growth horizon before the risk of critical surcharge will
occur. This horizon may be extended if existing flow conditions (i.e., based
upon on flow monitoring results) are representative of future flow conditions.
The identification
of potential solutions to address the risk of surcharge as development in the
SUC proceeds to build-out was beyond the scope of this Master Servicing Study.
However, as noted above, the anticipated rate of build-out will afford
sufficient time for the City to complete the required EA studies and identify
any capital improvement projects required to accommodate build-out in the whole
of the WRC catchment area.
Development within
Barrhaven South can therefore proceed at the proposed development densities, as
the City will undertake the required capacity allocation planning for the WRC
trunk sewer.
Evaluation of
Wastewater Servicing Alternatives:
An evaluation of
wastewater servicing alternatives was conducted to determine a suitable
internal servicing concept. The two servicing alternatives reviewed were:
Alternative
I: Implementation of a new wastewater
system including a treatment plant and collection system.
Alternative II: An
extension of the existing wastewater system, including all works necessary to
connect to the existing system.
The evaluation of
alternatives was based, in part, on criteria previously used by the former
Region of Ottawa-Carleton in the preparation of Master Plans for Water,
Wastewater and Transportation. The criteria are comprised of four main
categories including Constructability/Functionality, Economy, Caring and
Healthy Community, and Natural Environment.
Based upon this evaluation, Alternative II was selected as the preferred
solution. The preferred wasterwater servicing plan is shown on Figure SAN-1 in
Document 6.
Water Servicing:
The major water
distribution infrastructure components required to service the Barrhaven
Pressure Zone were identified in a previous consultant study (Barrhaven, 2W and
3W Pressure Zones Infrastructure Assessment, Stantec Consulting Ltd., 2002).
With respect to major water distribution infrastructure outside of the
Barrhaven Pressure Zone, reference is made to the 2002 Stantec study that
identified piping requirements to both Barrhaven and the SUC based on
anticipated demands. This Master Servicing Study evaluated two water servicing
alternatives and completed hydraulic
analyses to confirm the adequacy and reliability of the proposed system to
service Barrhaven South.
Evaluation of
Water Servicing Alternatives
To accommodate
development within Barrhaven South and surrounding areas, an evaluation of two
water supply and distribution alternatives was completed, using the same
prescribed criteria as were applied for the wastewater servicing alternatives.
In terms of location, all watermains have been located within transportation
corridors identified through the Barrhaven South CDP.
Alternative I:
Implementation of a new water system including a water source, treatment plant
and/or distribution system.
Alternative II: An
expansion of the existing water distribution system, including new equipment
and facilities to increase the system capacity.
Based upon the
evaluation, Alternative II was selected as the preferred water supply
alternative. The preferred water supply
plan is shown on Figure WM-1 in Document 6.
Hydraulic Analyses
of Proposed Water Distribution System:
Barrhaven South is
located adjacent to the existing Barrhaven Pressure Zone (Zone BAR). Based upon current growth projections,
hydraulic analyses were completed that confirmed the adequacy and reliability
of the proposed water distribution system.
Storm
Drainage/Stormwater Management
Stormwater
management criteria and the approach to accommodating the four existing
municipal drains/tributaries within the study area were determined through the
preparation of the Jock River Reach 1 Subwatershed Study (Stantec, 2007) and
the Conceptual Fisheries Compensation Plan (Niblett Environmental Associates,
2006) as summarized previously in this staff report. The Master Servicing Study made use of these recommendations and
SWM design criteria to develop conceptual storm drainage and stormwater
management servicing plans for the study area.
Evaluation of
Stormwater Management Servicing Alternatives
Five different
stormwater management servicing alternatives were considered and
evaluated. The criteria used to assess
the stormwater management alternatives differed from those used to assess the
wastewater and water servicing alternatives as a result of different
constraints. An initial screening of
alternatives was based on the following evaluation criteria: Financial (40%);
Fish and Aquatic Life (25%); Terrestrial and Vegetation Communities (15%); Social/Community
(20%). The five SWM servicing alternatives that were evaluated are summarized
as follows:
Option #1
· Single facility with an outlet to the
Jock River east of Jockvale Road
· No allowance for the preservation of
any existing municipal drains
· All storm sewers are tributary to the
proposed pond
· One main trunk inlet to pond
Option #2
· Two facilities located adjacent to
the Jock River floodplain: one facility adjacent to Jockvale Road, the second
located east of Cedarview Road
· No allowance for the preservation of
any existing municipal drains
· Multiple trunk storm sewer inlets to
ponds
Option #3
· Three facilities
· Proposed to preserve and outlet
facilities to a portion of the existing West Clarke, Todd and Corrigan
municipal drains
· Proposed to rehabilitate for improved
fish habitat portions of drains to remain open
· Multiple trunk storm sewer inlets to
ponds
Option #4
· Five ponds
· Two facilities adjacent to floodplain
as per Option #2
· Two facilities along Todd drain
· One facility draining to West Clarke
drain south of Cambrian Road
· Proposed to maintain West Clarke and
Todd drains in existing configuration commencing just south of Cambrian Road to
the Jock River
Option #5
· Eight ponds
· Existing four municipal drains to
remain as is
· Multiple storm sewer inlets and
multiple ponds, reducing size of trunk sewers
The five
stormwater management alternatives were evaluated using the criteria and
weighting noted above. Based upon the
evaluation of the alternatives, Option 3 was identified as the preferred alternative and Option 4 had a
similar though lower score. Other
options had significantly lower scores.
Additional
geotechnical investigations undertaken in assocation with subdivision design
indicated that the planning level site grading assumptions used to confirm the
feasibiltiy of the options may not be achievable - specifically that the
assumed maximum grade raise of 1.5 m should be adjusted to a maximum grade
raise of 1.0 m. Based on this planning
level grade raise constraint, Option 3 was revisited. While Option 3 was confirmed to be feasible, it required
significant lowering of stormwater management ponds and pipes. A modification of Option 3 was investigated
- provision of two additional stormwater management facilities in the vicinity
of the most constrained soils in order to optimize grading planning (Document
6, Figure ST-1). This modification
maintains all of the natural environment factors which were seen as beneficial
in Option 3, including the Conceptual Fish Habitat Compensation Plan. Additional fisheries enhancement
opportunities may be identified at detailed design.
Storm Drainage
Following from the
selection of the preferred stormwater management alternative, preliminary
design was completed for the SWM facilities, the storm sewer systems tributary
to each of the SWM facilities, and the
two rehabilitated municipal drains.
Storm Sewer System
Design:
The design of the
storm trunk sewers was generally established by following the proposed roadway
layout and in accordance with City design criteria. The storm servicing network
in shown on Figure ST –1 in Document 6.
Additional
subsurface investigations of the study area have identified soil conditions
(compressible silty clays) which limit the extent to which the site may be
raised: a maximum fill depth of 1.0 meter above existing grade has been assumed
for preliminary design. Given the low
lying areas in the northern portion of the study area and the grade raise
restrictions noted above, much of the storm sewer system will be shallow and
above conventional basement level.
Building foundations require drainage to protect from flooding and
structural damages. These grade raise
constraints will preclude the use of standard depth basements over a portion of
the study area, expected to account for over 1000 homes in the development
area.
In consideration
to the physical constraints to conventional building forms noted above,
engineering methods to achieve higher grade raises were discussed. These can include the use of piled
foundations, light weight backfill, pre-consolidation of soils through loading
or dewatering and other methods. Such
methods can be investigated in further detail once more detailed site-specific
soils information is available and the final form of development is determined.
In addition,
alternatives to conventional basement level foundation drain connections to the
storm sewer system were also considered - foundation drain collector (FDC)
systems and sump pumps. FDC systems use
a dedicated pipe to collect only foundation drainage. Use of such systems as the basis of community service planning
was rejected. Such systems represent a
complete additional piped system to build and maintain, and again due to
generally flat lands a gravity outlet to such a system was considered difficult
to achieve. The use of sump pumps was
also discussed as a means to provide building foundation drainage where storm
sewers would be above basement level.
Issues such as homeowner perceptions and expectations and reliability of
power sources and backup systems were discussed. This option was not considered an acceptable design practice upon
which to base the master planning of storm systems in a greenfield development
area.
Accordingly, through
the Community Design Plan process, an effort was made to maximize land uses in
the affected area that will not require basements, thus being unaffected by the
unavoidably shallow storm sewers. In
response, Greenbank Road was relocated further west, and school sites and
commercial lands were introduced to reduce the affected area. Notwithstanding this effort, there remains a
portion of the site slated for residential development that will require
consideration of building form, foundation drainage and engineering
measures. The area affected by grade
raise constraints and/or shallow storm sewers is shown on Figure GT-1 in
Document 6.
Operation and
Maintenance Considerations for Standing Water in Storm Sewers
As discussed
previously, site constraints present storm servicing challenges. The north half of the site is very flat; the
Jock River corridor has no defined valley offering no opportunity to deepen
storm outlets; and there are fill constraints over part of the site. Based upon preliminary design, this
combination of challenges has resulted in a storm sewer system where storm
pipes do not drain naturally by gravity.
Also, in many areas there will be minimal (frost) cover over the pipes. The length of storm pipe subject to these
constraints is estimated to be approximately 9000 m.
Storm sewers which
do not drain naturally by gravity can signficantly increase the costs to the
City to own, operate and maintain the affected sewers. Where storm pipes do not drain naturally by
gravity, standing water will result in sedimentation build up within the storm
sewer system. As such, during detailed
design, an appropriate solution to address sedimentation resulting from the
submerged condition must be developed. Consideration will be given to a range
of options that provide for drawing down the affected sewers and sediment
forebays in stormwater management ponds to create free flow conditions and
self-cleansing velocities at the start of the next rainfall event. Staff of the Wastewater and Drainage Services
Division of the Public Works and Services Department were consulted throughout
the preliminary design of the storm drainage system and have concurred with the
above approach to determine the most appropriate solution at the detailed
design stage.
Rehabilitated Tributaries (Municipal Drains)
As recommended
through the Jock Reach 1 Subwatershed Study and further detailed in the
Conceptual Fish Habitat Compensation Plan, the East Clarke Drain and the
majority of the Corrigan tributary will be enclosed. The West Clarke and Todd Drains will be partially enclosed,
relocated and rehabilitated to improve fish habitat. The rehabilitated drains/tributaries will also serve as the
conveyance channel for flows discharging from the proposed stormwater management
facilities.
Preliminary design
of the rehabilitated drains has been completed including the determination of
plan forms, meander belt widths, cross-sectional dimensions, and longitudinal
profiles. The cross-sections have been designed
to convey 100-year peak flows from the SWM facilities. The low flow channels have been designed
applying natural channel design principles with a sequence of riffles and pools
to enhance fish habitat.
Next Steps
The Barrhaven
South Master Servicing Study will be finalized after City Council approves the
recommended projects to service the development area. Notices of Completion will be published for the Jock River Reach
1 Subwatershed Study and Barrhaven South Master Servicing Study notifying the
public of the availability of the reports and the 30-day public review
period.
The Notice of
Completion for the Master Servicing Study will identify the following preferred
projects:
· Wastewater collection system
(Schedule B)
· Water distribution system (Schedule
B)
· Enclosure/partial enclosure of four
watercourses – East Clarke Drain, West Clarke Drain, Todd Drain and Corrigan
Drain (Schedule B)
· Construction of five stormwater
detention facilities and associated storm drainage collection systems,
including:
o Corrigan SWM Pond and associated storm
sewers (Schedule B)
o Todd SWM Pond and associated storm
sewers (Schedule B)
o Greenbank SWM Pond and associated
storm sewers (Schedule B)
o Clarke SWM Pond and
associated storm sewers (Schedule B)
o Cedarview SWM Pond and associated storm sewers (Schedule B)
ENVIRONMENTAL IMPLICATIONS
Subwatershed planning is an integrated, ecosystem approach to land use planning based on the natural boundaries of a drainage area. The Jock River Reach 1 Subwatershed Plan provides an environmental road map for City staff, developers, agencies, landowners and stakeholders to properly plan development in the subwatershed that aims at protecting and improving the long-term health and viability of its natural resources. The environmental analysis conducted through the subwatershed study has informed and guided the envelope of built form, design layout and development guidelines for Barrhaven South Community Design Plan that is aimed at meeting the City’s goal of sustainable development.
The Barrhaven South Conceptual Fish Habitat Compensation Plan was developed by applying an integrated planning approach as recommended in the Lower Rideau Watershed Strategy. Examining and understanding the fisheries resources within the tributaries and Jock River has enabled a proactive, holistic approach to be undertaken that recognizes development and servicing requirements while ensuring a net gain in fisheries habitat and productive capacity. Although loss of fish habitat through tributary enclosures will occur through the development of Barrhaven South, the opportunity to improve the remaining tributaries and creation of new spawning habitat will result in twice as much improved/created fish habitat area as is anticipated to be lost.
The subwatershed study has informed the identification and planning of infrastructure in Barrhaven South to ensure there is no conflict with the infrastructure servicing and environmental recommendations. The recommended infrastructure projects have been identified through a Class Environmental Assessment process. As such, the environmental conditions, impact assessment, mitigation and monitoring measures have been accounted for in determining the preferred alternatives.
The subwatershed study focuses on the environmental and conceptual stormwater management requirements associated with future development lands. There is a small portion of the study area in the rural area as well as floodplain lands under agricultural operation in the urban area. There are six recommendations pertaining to rural/ agricultural lands:
· Promote agricultural Best Management Practices (BMPs) through the Lower Rideau Watershed Strategy implementation committee.
· Removal of municipal drains in Barrhaven South to be abandoned prior to development. Consent of all signatories on original agreement required.
· Provide a recreational trail along both sides of the Jock River - pathway to be implemented as part of the development approval process; in non-development area, investigate opportunities for pathway, where feasible, contingent on landowner consent.
· Country lot estate development north of Fallowfield Road - use of lot and conveyance measures to be maximized to achieve SWM design criteria prior to consideration of end-of-pipe facilities.
· For the development north of the river, two stormwater management facilities are conceptually identified on lands partially within the floodplain. The lands to accommodate the facility would have to be acquired from the landowner.
· Further environmental investigation of woodlot W4 subject to permission by the landowner.
All of these recommendations will require further action and consultation with the affected landowners. Implementation of the recommendations is subject to the landowner agreement.
CONSULTATION
A
comprehensive public consultation program was developed to integrate and
facilitate the CDP and technical studies process meeting the requirements of
both the Planning Act and Environmental Assessment Act. A total of four (4) formal public open
houses for this project were held at the Walter Baker Centre in the Barrhaven
community on:
· April 14, 2005 – Introduction to the
Study / Phase 1 of EA
· July 20, 2005 – Presentation of
Alternative Solutions / Phase 2 of EA
· January 26, 2006 – Evaluation of
Alternative Solutions / Phase 2 of EA
· March 29, 2006 – Selection of
Preferred Solution / Phase 2 of EA
These
public events involved opportunities for the public to review the analysis and
work to date, and to ask questions to City staff and the full consulting
team. Notices for all public meetings
addressed both the planning process, as well as all requirements of the environmental
assessment (EA) process. In addition to
the Open Houses that specifically focused on the Barrhaven South CDP and the
technical studies, the project team also participated in general open houses
hosted by the Ward Councillor in October 2005 and April 2006.
The
Subwatershed and Master Servicing Studies solicited input from various City
divisions within Planning, Transit and Environment and Public Works and
Services Departments. In addition to
the involvement of City staff, many government agencies and approval
authorities were involved in the planning and technical study process. A formal Technical Advisory Committee (TAC)
was established for the CDP process. In
addition, a technical sub-committee was formed for both the subwatershed and
master servicing study to discuss in detail the issues relevant to these
technical studies. For the subwatershed
study, the sub-committee was represented by staff from the City, Rideau Valley
Conservation Authority (RVCA), Department of Fisheries and Oceans (DFO),
Ministry of Environment (MOE) and the Ministry of Natural Resources (MNR). These provincial and federal agencies were
also contacted individually for specific advice and input regarding relevant
issues and approvals as they arose.
Sub-committee members were provided the interim and draft reports for
review and input.
A
total of eight TAC and sub-committee meetings were held over the course of the
project. Verbal and/or written comments
were received from MOE, MNR, RVCA, DFO, and City staff at major milestones of
the study, including review of draft and final reports. All comments received from City staff and
government agencies have been addressed and incorporated into the final
documents. TAC members were made aware
of soils constraints and the modification of the preferred alternative.
For
the subwatershed study, individual meetings and/or circulation of the interim
and final draft reports were provided to the City’s Ottawa Forest and
Greenspace Advisory Committee, the Friends of the Jock River and major
developers north of the Jock River.
Comments were received from Friends of the Jock River and OFGAC on the
interim report and draft final report respectively. A response to the comments received was provided to these two
public groups and relevant comments incorporated into the final report.
Two
meetings occurred with the major developers north of the Jock River on March 3,
2006 and January 19, 2007. The purpose
of the first meeting was to present the conceptual stormwater management
options for north of the Jock River to service the O’Keefe and Foster Ditch
drainage areas. The developers in
attendance concurred on Option 2 illustrating a three-pond scenario to service
the Foster and O’Keefe drainage areas.
The purpose of the January 19, 2007 meeting was to present the preferred
management plan and implementation strategy for north of the Jock River. Issues raised in the meeting were related to
development setbacks, Development Charges by-law amendment, and catchment area
boundary for studies on the Foster Ditch.
These issues were resolved through text modifications and commitment to
have further discussions during the DC by-law amendment process.
Overall the studies benefited from a broad range of technical advice and direction.
FINANCIAL IMPLICATIONS
The
infrastructure servicing projects as defined as local servicing in the
Development Charge By-law 2004-298, as recommended in the Barrhaven South
Master Servicing Study will be designed and constructed by developers.
The
Area-Specific Stormwater Development Charge By-law 2004-304 entitled Nepean
South Urban Centre Stormwater Facilities will have to be amended to reflect the
stormwater management solution identified north of the Jock River in the
subwatershed study and the required stormwater management facilities and
associated storm sewers identified in the Master Servicing Study for Barrhaven
South. The main development charge
by-law 2004-298 will be amended in the next five year review, as scheduled in
2009, for all remaining development charge eligible works.
As
discussed previously, site constraints will result in permanent standing water
in a significant portion of the storm sewer system. This result has the
potential to significantly increase long-term maintenance and operation costs
through the need for regular pumping to draw down the sewers and/or other
measures to manage the increased potential for sedimentation in the pipes. The long-term operation and maintenance
costs were not estimated as part of the master planning excercise. These costs will be determined at the
detailed design stage and identified in future budgets.
The fish habitat compensation project on City lands identified in the Barrhaven South CFCP will be the financial responsibility of the developers including land costs. Any financial requirements associated with environmental recommendations carried out by the City will be reflected in future program budgets, subject to Council approval. Securement of the two significant woodlands in private ownership is reflected in the Long-Range Financial Plan 3.
SUPPORTING DOCUMENTATION
Document
1 Study Area Location Map
Document 2 Jock
River Reach 1 Subwatershed Study and Conceptual Fish Habitat Compensation Plan
(distributed under separate cover)
Document 3 Environmental
Constraints and Opportunities Map and Key Findings
Document 4 Subwatershed
Management Plan
Document
5 Conceptual Stormwater Management
Option 2, North of the Jock River - Figure 6.4.2
Document 6 Master Servicing Projects: Figures SAN-1,
WM-1, ST-1, and GT-1
DISPOSITION
1. Planning, Transit and Environment will
finalize the Barrhaven South Master Servicing Study Class Environmental
Assessment Report and file the Notices of Completion to initiate the 30-day
public review period of the Master Servicing Study and Subwatershed Study. Once
the Class EAs are approved under the Environmental Assessment Act, projects
identified in the Master Servicing Study may proceed to detailed design and
final City approval through delegated authority.
2. Planning,
Transit and Environment will make the Jock River Reach 1 Subwatershed Study and
the Barrhaven South Master Servicing Study available through the main branch of
the Ottawa library, Barrhaven library branch and the Ben Franklin Client
Service Centre.
3. Legal
Services to bring forward to City Council the Barrhaven South draft Official
Plan Amendment implementing by-law.
4. Public
Works and Services to bring forward the abandonment report for municipal drains
situated in the Barrhaven South development area to City Council for approval.
5. Planning,
Transit and Environment will coordinate the detailed design, approval and
construction of the new fish habitat area on City lands.
6. Planning,
Transit and Environment will revise the Area-Specific Stormwater Development
Charge By-law 2004-304, for north and south of the Jock River and bring forward
for Council approval.
STUDY AREA LOCATION MAP DOCUMENT 1
ENVIRONMENTAL CONSTRAINTS AND
OPPORTUNITIES
MAP AND KEY FINDINGS DOCUMENT
3
· North
of the Jock River, the main tributaries are O’Keefe Drain, Foster Ditch and
Fraser Clarke Drain.
· South
of the Jock River, the main tributaries are the West Clarke Drain, East Clarke
Drain, Todd Drain and Corrigan tributary.
· O’Keefe, Fraser-Clarke, West Clarke, East Clarke and Todd tributaries are municipal drains.
· All
tributaries to the Jock River support fisheries and are considered fish
habitat.
· The
tributaries provide only a highly seasonal and marginal fish habitat for a handful
of warm water tolerant fish species.
· The
tributaries can run dry or low after high spring water levels.
· Tributaries
have been largely modified by channel straightening with little or no riparian
vegetation.
· As
per the Lower Rideau Watershed Strategy, if an integrated stormwater management
approach is undertaken consideration of partial or full enclosure of the drains
south of the Jock River can be considered if DFO requirements are fulfilled.
· Opportunity
exists to enhance low flows in the tributaries and Jock River through
stormwater management.
Terrestrial
Resources:
· A
total of 28 woodlands exist in the subwatershed.
· North
of the Jock River, Woodlot W44 (UNA #50), Woodlot W43 (UNA#60) and Woodlot W50
(UNA #183) are considered significant woodlands.
· South
of the Jock River, Woodlots W1 and W2 (UNA #57), Woodlot W4 (rural), Woodlot W7
(UNA #49) and W10 (UNA #58) are considered significant woodlands.
· Management
plans should be prepared to maintain environmental integrity of the woodlands
over the long-term.
· There
is very low representation of wetlands within Reach 1.
· A
total of 88 species of birds has been recorded as breeding in the area
including forest, edge and wetland species.
· Forest
interior habitat is contained within Woodlands W1 and W2 (UNA #57).
· A
total of 10 species of amphibians, 3 species of reptiles and 18 species of
mammals have been recorded.
· Significant
species reported or observed include one federal (butternut), one provincial
(greater redhorse fish species) and fourteen regionally rare species.
· Terrestrial
corridor function was identified along the Jock River.
· Terrestrial
corridor potential was identified along the O’Keefe Drain connecting Stony
Swamp and the Jock River.
Jock
River:
· Jock
River is highly productive fisheries resource that contains healthy populations
of naturally reproducing game fish such as muskellunge.
· A
number of important and/or critical fish habitat areas within the main stem of
the Jock River have been identified within Reach 1.
· There
is limited riparian vegetation along the river corridor.
· Groundwater
flow is generally towards the river that is identified as a discharge area.
· Recharge
area function associated with sand and gravel resource areas, south of Cambrian
Road, was identified.
· Low
summer flows in the Jock River.
· Jock
River water quality is highly impaired and does not meet provincial water
quality criteria.
· The
Jock River is classified as a Policy 2 watercourse for phosphorus, which
requires a net reduction in phosphorus loadings to the river.
· The
extent of the regulatory floodplain through Reach 1 is defined by the 100-year
flood as per mapping recently updated by the Rideau Valley Conservation
Authority in November of 2005
· Through
the fluvial geomorphoric investigation, the meander belt width was determined
for the Jock River corridor representing the maximum lateral extent of the
channel voer time. Meander belt is
considered a hazard constraint that needs to be considered in establishing
development setbacks from the river.
· Further erosion and migration analysis is recommended for Reaches 1 and 2 of the Jock River to confirm meander belt width.
SUBWATERSHED
MANAGEMENT PLAN DOCUMENT
4
North of the Jock River
Management Plan
Based on the preferred stormwater
management option for north of the Jock River, a conceptual stormwater
management plan and natural environment plan have been developed individually
for the O’Keefe Drain and Foster Ditch drainage areas which are summarized
below. Recommendations have also been
made for the Kennedy-Burnett and Fraser Clarke Drain catchment area to be
included in a future design study.
|
O’Keefe Drain
Catchment Area Stormwater Management Plan |
|
|
Location |
Recommendation |
|
North of Fallowfield Road |
Country Lot Development – Use of lot level and conveyance measures to be maximized to achieve SWM design criteria prior to consideration of end-of-pipe facilities. |
|
South of Fallowfield Road |
To service lands between Strandherd Drive and McKenna Casey Drive – provide centralized, off-line SWM facility located south of McKenna Casey. |
|
O’Keefe Drain
Catchment Area Natural Environment Plan |
|
|
Feature |
Recommendation |
|
Woodlot #44 |
City to protect Woodlot #44 identified as significant woodland currently in private ownership. |
|
Other Terrestrial Features |
Conserve and integrate, where feasible, woodlands stands and vegetation associated with woodlots north of Fallowfield Road. |
|
O’Keefe Drain/
Aquatic Habitat |
Preserve and enhance aquatic habitat and riparian zone of the tributary through future rehabilitation opportunities. |
|
O’Keefe Drain Corridor |
Investigate feasibility of establishing and enhancing the terrestrial linkage along O’Keefe Drain from Jock River corridor to Stony Swamp. |
|
Watercourse Setback Requirement |
Setback requirements will be the greater of the100-yr floodline elevation/meander belt width/aquatic habitat buffer |
|
Recreational Trail |
Incorporate trail system along O’Keefe Drain as identified in Official Plan and Greenspace Master Plan. |
|
Foster Ditch Catchment Area Stormwater
Management Plan |
|
|
Location |
Recommendation |
|
North of Maravista |
To service the undeveloped lands north of Maravista and existing developments east of Cedarview Road – provide a centralized SWM facility consisting of a wet pond and create an additional area of fish habitat to compensate for loss of habitat due to proposed partial enclosure/alignment of the Foster Ditch |
|
North of McKenna Casey South of Maravista |
To service the area north of McKenna Casey Drive between Cedarview and Strandherd not serviced by the Maravista SWM Pond and the area not serviced by the O’Keefe Pond – provide a centralized off-line stormwater facility located south of McKenna Casey Drive. Existing Foster Pond located at mouth of Foster Ditch to be decommissioned and temporary SWM pond (north of railway on parkland) to be removed. |
|
Foster Ditch Catchment Area Natural Environment Plan |
|
|
Feature |
Recommendation |
|
Ditch/Tributary Corridor |
Preserve and enhance the aquatic habitat and riparian zone of the tributary through future restoration opportunities. |
|
Watercourse Setback Requirement |
Setback requirement will be the greater of the 100-yr floodline elevation/meander belt width/aquatic habitat buffer |
|
Kennedy-Burnett/Fraser Clarke Catchment Area Stormwater Management
Plan |
|
|
Location |
Recommendation |
|
Kennedy-Burnett SWM Facility/ Fraser Clarke Drain |
Future retrofit and expansion of Kennedy-Burnett stormwater management facility to accommodate and treat stormwater runoff from existing and future developments within Kennedy-Burnett and Fraser-Clarke drain catchment area. |
|
Kennedy-Burnett/Fraser Clarke Catchment Area Natural Environment Plan |
|
|
Feature |
Recommendation |
|
Ditch/Tributary Corridor |
Preserve and enhance the aquatic habitat and riparian zone of the tributary through future restoration opportunities. |
|
Watercourse Setback Requirement |
Setback requirement will be the greater of the 100-yr floodline elevation/meander belt width/aquatic habitat buffer |
South of the Jock River
Management Plan
The Barrhaven South development
will have four main catchment areas: the
Cedarview Ditch, West Clarke Drain, the Todd Drain and the Corrigan
Ditch. Stormwater management and
natural environment plans have been developed for each catchment area. The East Clarke, West Clarke and Todd
municipal drains will require abandonment as per the Drainage Act before or in
conjunction with development proceeding.
These drains are entirely contained within the urban area and all lands
draining into these drains will be urban development consistent with the
Council approved Community Design Plan.
|
Cedarview Ditch
Catchment Area Stormwater Management Plan |
|
|
Location |
Recommendation |
|
Northeast of Cedarview Road |
Provide one centralized stormwater management facility (wet pond) located northeast of Cedarview Road, south of the Jock River; create new enhanced outlet channel which will be used to convey stormwater runoff to the Jock River. |
Cedarview Ditch
Catchment Area Natural Environment Plan |
|
|
Feature |
Recommendation |
|
Woodlot W1 and W2 (UNA #57) |
Protect core area of Woodlot W1 and W2 (UNA #57) as identified as significant woodland and prepare a management plan for the woodland to maintain and enhance environmental quality. |
|
Other terrestrial features |
Conserve and integrate, where feasible, woodlot W3 and other vegetation/hedgerows. |
|
Tributary/ Aquatic Habitat |
Tributary creation and enhancement for new outlet to the Jock River |
|
Tributary Corridor/ Setback |
New tributary corridor to be 30 metres wide with 5-metre buffer from top of bank on both sides of the corridor (40 metres). Establish riparian vegetation along both sides of new channel. |
|
Sand and Gravel Resource Area |
Maintain groundwater recharge function under existing and future conditions |
|
West Clarke Drain
Catchment Area Stormwater Management Plan |
|
|
Location |
Recommendation |
|
West Clarke Drain – north of Cambrian Rd |
Provide one centralized stormwater management facility (wet pond) located north of Cambrian Road; partial enclosure of West Clarke drain and full enclosure of East Clarke Drain; rehabilitate/relocate remaining drain, which will be used to convey stormwater runoff to the Jock River. |
|
West Clarke Drain
Catchment Area Natural Environment Plan |
|
|
Feature |
Recommendation |
|
Other terrestrial features |
Conserve and integrate, where feasible, other vegetation/ hedgerows. |
|
Tributary/ Aquatic Habitat |
Tributary realignment and restoration including meandering stream/linear wetland. |
|
Tributary Corridor/ Setback |
New tributary corridor to be 30 metres wide with 5-metre buffer from top of bank on both sides of the corridor (40 metres). Establish riparian vegetation along both sides of new channel. |
|
Todd Drain Catchment Area Stormwater Management Plan |
|
|
Location |
Recommendation |
|
Todd Drain at Cambrian Road |
Provide two centralized stormwater management facility (wet pond): one pond located south of the new Greenbank Road alignment (Greenbank Pond) with the second pond straddling Cambrian Road (Todd Pond); partial enclosure of Todd Drain; rehabilitate/relocate Todd Drain, which will be used to convey stormwater runoff to the Jock River from Todd Pond. |
|
Todd Drain Catchment Area Natural Environment Plan |
|
|
Feature |
Recommendation |
|
Other Terrestrial Features |
Conserve and integrate, where feasible, vegetation associated with woodlots W3, W22 and other vegetation/hedgerows. |
|
Tributary / Aquatic Habitat |
Tributary realignment and restoration applying natural channel design; fish habitat improvements at mouth and creation of pool-riffle habitat within stream. |
|
Tributary Corridor/ Setback |
New tributary corridor to be 30 metres wide with 5-metre buffer from top of bank on both sides of the corridor (40 metres). Establish riparian vegetation along both sides of new channel. |
|
Organic Soils |
City to amend Schedule K – Environmental Constraints of the Official Plan to remove organic soils area situated west of Greenbank Road, southeast of Cambrian Road based on hydrogeologic investigation. |
|
Corrigan Drain Catchment Area Stormwater
Management Plan |
|
|
Location |
Recommendation |
|
Corrigan Drain at Jock River (city land) |
Provide one centralized stormwater management facility (wet pond) located north of Cambrian Road; enclose Corrigan Drain. |
|
Corrigan Drain Catchment Area Natural Environment Plan |
|
|
Location |
Recommendation |
|
Woodlots W7, W10, W50 along shoreline |
Protect and conserve significant woodlots W7, W10, W50 (all in city ownership) and City to prepare a management plans for the woodlands to maintain and enhance environmental quality. |
|
Woodlot W4 |
Environmental investigation of W4 in the rural area. |
|
Other terrestrial features |
Conserve and integrate, where feasible, woodlot stands within W4, W9, W11, W12 and other vegetation/hedgerows. |
|
Tributary/ Aquatic Habitat |
Tributary realignment and restoration applying natural channel design principles and establish riparian vegetation along new channel corridor. |
|
Watercourse Setback Requirement |
No development setback required (situated on parkland/ floodplain). |
The Jock River Corridor
Management Plan
The subwatershed study identified
a number of recommendations associated with the Jock River Corridor that are aimed
at preserving and improving the terrestrial, aquatic, water quality and
recreational aspects of this important river system.
|
Jock River Corridor Management Plan |
|
|
Feature |
Recommendation |
|
Water Quality |
Improve Jock River water quality through the implementation of enhanced level treatment of runoff in the urban area. Promote agricultural Best Management Practices through the Lower Rideau Watershed Strategy implementation committee. |
|
Floodplain |
Maintain the regulatory floodplain by not permitting active development within its limits. Some reduced risk uses such as sports fields and trails may be considered subject to RVCA approval. Any minor changes to the existing floodplain to proceed on the basis of cut and fill only subject to RVCA approval. |
|
Riparian Corridor |
City in partnership with RVC to prepare a Jock River Corridor Riparian Planting Plan to improve and enhance riparian vegetation coverage along the banks and shoreline of the river. |
|
Aquatic Habitat |
Continue to protect critical fish habitat and spawning areas along the Jock River and tributary mouths. |
|
Creation of Aquatic Habitat (city lands) |
Create pike spawning habitat area adjacent to Foster Dry Pond as compensation for loss of fish habitat in tributaries within Barrhaven South. |
|
Setback Requirement |
Development setback for the Jock River will be the greater of: floodplain, meander belt width, geotechnical, 15 metre top of defined bank or 30 metres from normal high water mark, whichever is greater. Further erosion and migration rate analysis required along Reach 1 and 2 of the Jock River to confirm meander belt width. |
|
Recreational Pathway |
Provide recreational trail along the Jock River as per Official Plan and Greenspace Master Plan. Recreational pathway to be implemented through the development approval process. For lands not subject to development, City to investigate opportunities for pathway, where feasible. |
CONCEPTUAL STORMWATER MAGEMENT
OPTION 2,
NORTH OF THE JOCK RIVER – FIGURE
6.4.2 DOCUMENT
5
MASTER SERVICING PROJECTS: FIGURES SAN-1, WM-1,
ST-1,
AND GT-1 DOCUMENT
6
