Mitigation Guide for the Protection of Fishes

Mitigation Guide for the Protection of Fishes
Mitigation Guide for the Protection of Fishes
and Fish Habitat to Accompany the
Species at Risk Recovery Potential
Assessments Conducted by Fisheries and
Oceans Canada (DFO) in Central and Arctic
Region
Version 1.0
G.A. Coker, D.L. Ming, and N.E. Mandrak
Ontario Great Lakes Area
Fisheries and Oceans Canada
PO Box 5050, 867 Lakeshore Rd.
Burlington, Ontario
L7R 4A6
2010
Canadian Manuscript Report of
Fisheries and Aquatic Sciences 2904
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Canadian Manuscript Report of
Fisheries and Aquatic Sciences 2904
2010
MITIGATION GUIDE FOR THE PROTECTION OF FISHES AND FISH HABITAT
TO ACCOMPANY THE SPECIES AT RISK RECOVERY POTENTIAL
ASSESSMENTS CONDUCTED BY FISHERIES AND OCEANS CANADA (DFO) IN
CENTRAL AND ARCTIC REGION
VERSION 1.0
by
G.A. Coker1, D.L. Ming 2, and N.E. Mandrak 3
Ontario Great Lakes Area
Fisheries and Oceans Canada
PO Box 5050, 867 Lakeshore Rd.
Burlington, Ontario
L7R 4A6
1
Portt and Associates, 56 Waterloo Avenue, Guelph, Ontario N1H 3H5
Fisheries and Oceans Canada, Ontario Great Lakes Area, Fish Habitat Management,
867 Lakeshore Road, Burlington, Ontario L7R 4A6
3
Fisheries and Oceans Canada, Great Lakes Laboratory for Fisheries and Aquatic
Sciences, 867 Lakeshore Road, Burlington, Ontario L7R 4A6
2
© Her Majesty the Queen in Right of Canada, 2010.
Cat. No. Fs 97-4/2904E ISSN 0706-6473
Correct citation for this publication:
Coker, G.A., Ming, D.L., and Mandrak, N.E. 2010. Mitigation guide for the protection of
fishes and fish habitat to accompany the species at risk recovery potential
assessments conducted by Fisheries and Oceans Canada (DFO) in Central and
Arctic Region. Version 1.0. Can. Manuscr. Rep. Fish. Aquat. Sci. 2904: vi + 40 p.
ii
TABLE OF CONTENTS
LIST OF FIGURES ......................................................................................................... III
LIST OF TABLES ........................................................................................................... IV
LIST OF APPENDICES.................................................................................................. IV
ABSTRACT ..................................................................................................................... V
PREFACE ...................................................................................................................... VI
INTRODUCTION ............................................................................................................. 1
PURPOSE....................................................................................................................... 2
APPROACH .................................................................................................................... 2
HOW TO USE THIS DOCUMENT .................................................................................. 3
MITIGATION STRATEGIES............................................................................................ 3
ALTERNATIVE ACTIVITIES ............................................................................. 3
OPERATIONAL STATEMENTS ....................................................................... 3
MITIGATION MEASURES BASED ON POE DIAGRAMS ................................ 4
REFERENCES ................................................................................................................ 4
LIST OF FIGURES
Figure 1.
Figure 2.
Figure 3.
Figure 4.
Figure 5.
Figure 6.
Figure 7.
Figure 8.
Figure 9.
Figure 10.
Figure 11.
Figure 12.
Figure 13.
Figure 14.
Figure 15.
Figure 16.
Figure 17.
Figure 18.
Figure 19.
Figure 20.
Master Pathway PoE Diagram: Land-based activities. .................................. 7
Master Pathway PoE Diagram: In-water activities. ........................................ 7
PoE Diagram 1 - Vegetation clearing. ........................................................... 8
PoE Diagram 2 - Grading. ........................................................................... 10
PoE Diagram 3 - Excavation. ...................................................................... 12
PoE Diagram 4 - Use of explosives. ............................................................ 14
PoE Diagram 5 - Use of industrial equipment. ............................................ 15
PoE Diagram 6 - Cleaning or maintenance of bridges or other structures. . 17
PoE Diagram 7 - Riparian planting. ............................................................. 18
PoE Diagram 8 - Streamside livestock grazing. .......................................... 19
PoE Diagram 9 - Marine seismic surveys.................................................... 20
PoE Diagram 10 - Placement of material or structures in water. ................. 21
PoE Diagram 11 - Dredging. ....................................................................... 23
PoE Diagram 12 - Water extraction. ............................................................ 25
PoE Diagram 13 - Organic debris management.......................................... 26
PoE Diagram 14 - Wastewater management. ............................................. 28
PoE Diagram 15 - Addition or removal of aquatic vegetation. ..................... 29
PoE Diagram 16 - Flow management. ........................................................ 31
PoE Diagram 17 - Fish passage issues. ..................................................... 33
PoE Diagram 18 - Structure removal. ......................................................... 35
iii
LIST OF TABLES
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.
Table 8.
Table 9.
Table 10.
Table 11.
Table 12.
Table 13.
Table 14.
Table 15.
Table 16.
Table 17.
Table 18.
Table 19.
Examples of typical activities and associated impacts, with corresponding
alternative activities that can significantly reduce the potential impacts. ........ 6
Mitigation measures based on PoE Diagram 1 - Vegetation clearing............. 9
Mitigation measures based on PoE Diagram 2 -Grading. ............................ 11
Mitigation measures based on PoE Diagram 3 - Excavation. ....................... 13
Mitigation measures based on PoE Diagram 4 - Use of explosives. ............ 14
Mitigation measures based on PoE Diagram 5 - Use of industrial
equipment..................................................................................................... 16
Mitigation measures based on PoE Diagram 6 - Cleaning or maintenance of
bridges or other structures........................................................................... 17
Mitigation measures based on PoE Diagram 7 - Riparian planting .............. 18
Mitigation measures based on PoE Diagram 8 - Streamside livestock
grazing.......................................................................................................... 19
Mitigation measures based on PoE Diagram 9 - Marine seismic surveys. ... 20
Mitigation measures based on PoE Diagram 10 - Placement of material or
structures in water. ....................................................................................... 22
Mitigation measures based on PoE Diagram 11 - Dredging. ........................ 24
Mitigation measures based on PoE Diagram 12 - Water extraction. ............ 25
Mitigation measures based on PoE Diagram 13 - Organic debris
management. ............................................................................................... 27
Mitigation measures based on PoE Diagram 14 - Wastewater
management. ............................................................................................... 28
Mitigation measures based on PoE Diagram 15 - Addition or removal of
aquatic vegetation. ....................................................................................... 30
Mitigation measures based on PoE Diagram 16 - Flow management. ......... 32
Mitigation measures based on PoE Diagram 17 - Fish passage issues. ...... 34
Mitigation measures based on PoE Diagram 18 - Structure removal. .......... 36
LIST OF APPENDICES
Appendix A: Mitigation measures to break the paths in the Pathways of Effects (PoE)
diagrams....................................................................................................37
iv
ABSTRACT
Coker, G.A., Ming, D.L., and Mandrak, N.E. 2010. Mitigation guide for the protection of
fishes and fish habitat to accompany the species at risk recovery potential
assessments conducted by Fisheries and Oceans Canada (DFO) in Central and
Arctic Region. Version 1.0. Can. Manuscr. Rep. Fish. Aquat. Sci. 2904: vi + 40 p.
This document was developed to accompany the Recovery Potential Assessments
(RPA) for aquatic species at risk conducted by Fisheries and Oceans Canada (DFO) in
Central and Arctic Region. One of the required components of the RPA is to identify
mitigation strategies and alternative activities that would protect species at risk against
identified threats. Threats to species at risk are identified in: COSEWIC species status
reports; DFO pre-COSEWIC assessments; DFO RPAs; and, recovery strategies and
management plans.
This document identifies example alternative and mitigation measures to activities that
threaten fishes and fish habitat, including species at risk. In conjunction with the RPA,
recovery teams can use these generic examples to determine if there are appropriate
mitigation actions for activities that may threaten aquatic species at risk. A list of all
unique mitigation measures, with associated coded pathway links, is also provided.
RÉSUMÉ
Coker, G.A., Ming, D.L., and Mandrak, N.E. 2010. Mitigation guide for the protection of
fishes and fish habitat to accompany the species at risk recovery potential
assessments conducted by Fisheries and Oceans Canada (DFO) in Central and
Arctic Region. Version 1.0. Can. Manuscr. Rep. Fish. Aquat. Sci. 2904: vi + 40 p.
Le présent document a été préparé pour accompagner les évaluations du potentiel de
rétablissement (EPR) des espèces aquatiques en péril, réalisées par Pêches et Océans
Canada (MPO) dans la région du Centre et de l’Arctique. La définition de stratégies
d’atténuation et le développement d’activités de rechange, visant à protéger les
espèces en péril contre des menaces signalées, représentent l’une des composantes
obligatoires de l’EPR. Les menaces aux espèces en péril sont décrites dans les
documents suivants : les rapports de situation du COSEPAC sur des espèces; les
évaluations préalables à celles du COSEPAC du MPO; les EPR du MPO; les stratégies
de rétablissement et les plans de gestion.
Dans ce document, on cite des exemples de mesures d’atténuation et autres à prendre
en situation de menace au poisson, y compris les espèces en péril, et à l’habitat du
poisson. Ces exemples génériques, utilisés de pair avec l’EPR, permettraient aux
équipes de rétablissement de déterminer des mesures d’atténuation convenables en
situation de menaces possibles aux espèces aquatiques en péril. Une liste de
l’ensemble des mesures d’atténuation uniques et les liens pour les chemins d’accès
codés connexes y sont également fournis.
v
PREFACE
Note to Users: The development of this guidance document was funded by the
Species at Risk (SAR) program in the Central and Arctic Region (C&A) of DFO. It is
intended for the use of DFO and is subject to revision at any time. Please check with
the C&A SAR program to ensure that you are using the most current version available
of this guide.
This guide has been developed to provide supplementary information for the Species at
Risk Recovery Potential Assessments conducted by Fisheries and Oceans Canada
(DFO) in Central and Arctic Region.
vi
INTRODUCTION
The purposes of the federal Species at Risk Act (SARA) are to prevent wildlife species
from being Extirpated or becoming Extinct (Section 6), to provide for the recovery of
wildlife species that are Extirpated, Endangered or Threatened as a result of human
activity (Sections 37 to 55), and to manage species of Special Concern to prevent them
from becoming Endangered or Threatened (Sections 65 to 72). Currently, several fishes
and mussels are among the identified species at risk (SAR) on Schedule 1 of the SARA,
which is the legal list of species at risk in Canada (Sections 27 to 31). To obtain a
current list of fish and mussel species listed on Schedule 1 of the SARA, refer to the
SARA registry website (http://www.sararegistry.gc.ca).
The Minister of Fisheries and Oceans Canada (DFO) is the competent minister
responsible for aquatic species at risk other than individuals in, or on, federal lands
administered by the Parks Canada Agency. Once a species is listed under the SARA,
prohibitions against the killing, harming, harassing or taking of individuals and against
the damage or destruction of their residence apply (Sections 32 to 36). The Act also
requires that recovery strategies, action plans and management plans be developed for
all listed species (Sections 37 to 55). Recovery strategies and action plans should
include the identification of critical habitat. Once identified, critical habitat is protected
from destruction (Sections 56 to 64).
There is a permitting provision in the Act to allow activities that might otherwise be
prohibited to occur if: i) they are scientific research related to the conservation of the
species; ii) they are beneficial to the species; or, iii) affecting the species is incidental to
the carrying out of the activity. This provision includes strict preconditions that must be
met before permits can be issued (Sections 73 to 78). To the extent possible, DFO Fish
Habitat Management (FHM) will administer its Fisheries Act and Species at Risk Act
responsibilities in an integrated manner, in accordance with the Practitioner’s Guide to
the Species at Risk Act (SARA) for Habitat Management Staff (DFO 2007). Works or
undertakings that may contravene the SARA prohibitions may be authorized, providing
they do not compromise or conflict with SARA recovery strategies or plans, and the
SARA permitting preconditions have been met. There may also be provincial and/or
municipal and/or Conservation Authority legislation or policies that also pertain to
species at risk, such as the Endangered Species Act (2007) in Ontario.
The SARA changes the way federal environmental assessments consider species at
risk. The SARA amends the definition of "environmental effect" in the Canadian
Environmental Assessment Act (CEAA) to include species at risk, residence and critical
habitat (Section 137). Therefore, projects that require an environmental assessment
under CEAA will have to take into account the project's effects on listed wildlife species
and their critical habitats. In addition, during an environmental assessment, responsible
authorities are required to notify competent ministers if a species at risk is adversely
affected by the project and to ensure the implementation of mitigation and monitoring of
effects on species at risk.
A species Recovery Potential Assessment (RPA) process exists within DFO to provide
the scientific advice required to meet the various requirements of the SARA. One
1
aspect of an RPA is to help determine whether a species can sustain any harm without
jeopardizing its survival and/or recovery as well as list mitigation measures and
alternative activities that can be used to protect the species. In the case of a species
that has not yet been listed under SARA, the RPA provides scientific advice to consider
during the listing decision process. The RPA documents are being completed by DFO
Science for Endangered and Threatened fish and mussel species listed, or being
considered for listing, under SARA in the Central and Arctic Region (C&A). These
documents will be peer reviewed and published as Research Documents by the
Canadian Science Advisory Secretariat.
PURPOSE
This document was developed to provide information that would accompany the RPAs
for aquatic species at risk. One of the required components of the RPA is to identify
alternative activities and mitigation strategies that would protect SAR against identified
threats. Threats to species at risk are described in Committee on the Status of
Endangered Wildlife in Canada (COSEWIC) status reports, DFO pre-COSEWIC
assessments, RPAs, and recovery strategies and management plans. Threats related
to habitat are often identified for freshwater fish and mussel species at risk, and these
threats may be related to a number of development activities such as water crossings,
pipeline construction and drain maintenance activities. In conjunction with the RPA,
recovery teams can use these generic examples to determine if there are alternatives to
activities that may threaten aquatic species at risk or if there are appropriate mitigation
actions.
The set of alternatives and mitigation measures provided in this document are not only
applicable to SAR, but could also be applied to other fish and mussel species not listed
under SARA. Alternative activities and mitigation measures are described in general
terms and can be used by Fish Habitat Management staff when reviewing development
projects proposed in, and around, water under the Fisheries Act and SARA. It is not the
intent of this document to provide a comprehensive list of alternative activities and/or
mitigation strategies with exact wording for transfer into Fisheries Act Authorizations or
Letters of Advice issued by Fish Habitat Management staff in C&A. Depending on the
site-specific conditions of a proposed development project, alternatives or mitigations
not listed in this document may be required to ensure that fishes and fish habitat are
protected. Fish Habitat Management staff should refer to standard wording that has
been developed internally and specifically for Fisheries Act Authorizations or Letters of
Advice when approving a development project under the Fisheries Act and SARA.
APPROACH
The DFO Risk Management Framework (RMF) approach was used as a basis for
building the list of generic mitigation measures. For more information on the RMF refer
to DFO’s Practitioner’s Guide to the Risk Management Framework for DFO Habitat
2
Management Staff Version 1.0 (DFO 2006). In the RPA documents, habitat-related
threats are linked to the DFO FHM Pathways of Effect (PoE). In this document, each
pathway link in the 18 PoE diagrams was coded (e.g., 1-1, 1-2) and assigned a
mitigation measure. This process was conducted in-parallel with a careful examination
of the “Mitigation Measures Master Table” and the modified PoE diagrams of the
MTO/DFO/OMNR Protocol (MTO 2006), providing alternative or additional mitigation
details and terminology to further refine the list of mitigation measures. The mitigation
measures are purposely generic, as a list that attempted to address all variations of
project types would be overly complex and inherently incomplete.
HOW TO USE THIS DOCUMENT
This document is intended to be used in conjunction with RPAs to adequately identify
appropriate mitigation and monitoring measures for aquatic species at risk.
Alternatively, if this document is to be used to assist in project review for fish and fish
habitat, determine which PoEs and associated mitigation measures are applicable to
the proposed development project under review by Habitat Management staff. The
mitigation measures used for an individual project can be modified to ensure that they
are appropriate for site-specific project requirements. Again, note that the mitigation
measures are purposely generic, as a list that attempted to address all variations of
project types would be overly complex and incomplete
MITIGATION STRATEGIES
ALTERNATIVE ACTIVITIES
A key approach used by FHM staff to protect fishes and fish habitat, including aquatic
species at risk, from development activities includes encouraging proponents to
redesign their project, to select an alternate site, or to mitigate potential damages using
other reliable techniques, such as by installing adequate sediment and erosion control
equipment (DFO 1986). Table 1 does not provide a comprehensive list of alternative
activities, but is intended to provide examples of alternative activities that could be used
as a mitigation strategy to significantly reduce the potential impacts of a project
proposed in and around water.
OPERATIONAL STATEMENTS
A source of accepted mitigation measures that can be used to protect fishes and fish
habitat are contained within DFO Operational Statements. These were developed as
part of an initiative to streamline the DFO review and approval process for lower risk
projects. The Operational Statements inform a proponent about how to protect fishes
and fish habitat and to comply with the Fisheries Act by providing "bottom line" advice
for different types of low risk activities. The Operational Statements describe the
3
conditions and the measures to be incorporated into a project in order to avoid negative
impacts to fishes and fish habitat, allowing the project to proceed without a DFO review
if the conditions and measures to protect fishes and fish habitat listed in the applicable
Operational Statement are carried out. These Operational Statements are often
regionally specific, and provide advice ranging from the salvage of sunken logs or the
building of docks, to the construction of clear-span bridges, temporary stream crossings,
and the laying of underwater cables. Activities covered by Operational Statements that
may impact SAR have conditions that exclude their use in areas where the SAR are
found (e.g., Operational Statement for dredging cannot be used where mussel SAR are
found). Operational Statements can be found under Habitat Management in the main
DFO website (http://www.dfo-mpo.gc.ca/).
MITIGATION MEASURES BASED ON PoE DIAGRAMS
The mitigation measures outlined in the following tables are for activities that are not
covered by an Operational Statement. For 18 DFO Pathway of Effect (PoE) diagrams,
each pathway link has been coded (e.g., 1-1, 1-2) and assigned a mitigation measure.
The PoE diagrams are taken from DFO’s Practitioner’s Guide to the Risk Management
Framework for DFO Habitat Management Staff Version 1 (DFO 2006).
The PoE diagrams for the master pathways are provided in Figures 1 and 2. Individual
PoE diagrams (Figures 3-20) and the generic mitigation measures associated with them
(Tables 2-19) are presented. A list of all mitigation measures is provided in Appendix A.
REFERENCES
Clarke, K.D., Pratt, T.C., Randall, R.G., Scruton, D.A., and Smokorowski, K.E. 2008.
Validation of the flow management pathway: effects of altered flow on fish habitat
and fishes downstream from a hydropower dam. Can. Tech. Rep. Fish. Aquat. Sci.
2784: vi + 111 p.
DFO (Fisheries and Oceans Canada). 1986. Policy for the management of fish habitat.
http://www.dfo-mpo.gc.ca/oceans-habitat/habitat/policies-politique/operatingoperation/fhm-policy/index_e.asp (accessed March, 2009).
DFO (Fisheries and Oceans Canada). 2006. Practitioner’s guide to the risk
management framework for DFO Habitat Management staff. Version 1.0. Habitat
Management Program, Fisheries and Oceans Canada. http://www.dfompo.gc.ca/oceans-habitat/habitat/policies-politique/operating-operation/riskrisques/index_e.asp (accessed March 2009).
DFO (Fisheries and Oceans Canada). 2007. Practitioner’s guide to the Species at Risk
Act (SARA) for habitat management staff. Version 1.0. Habitat Management
Program, Fisheries and Oceans Canada. 69 p.
4
MTO (Ministry of Transportation of Ontario). 2006. Environmental guide for fish and fish
habitat, Section 6: Impact assessment and mitigation, Appendix 6C-Modified
pathways of effects diagrams. October 2006.
Wright, D.G., and Hopky, G.E. 1998. Guidelines for the use of explosives in or near
Canadian fisheries waters. Can. Tech. Rep. Fish. Aquat. Sci. 2107: iv + 34 p.
5
Table 1. Examples of typical activities and associated impacts, with corresponding alternative
activities that can significantly reduce the potential impacts.
Activities/Potential Impacts
Construction of bridge with in-water piers, or that
potentially destabilizes the stream banks.
Construction of pipeline or a cable crossing using a
traditional trench excavation across the
watercourse.
Rock fill coffer dam construction can have a
relatively large footprint, and potentially can expose
aquatic habitats to siltation during coffer dam
placement and removal.
Construction of hydroelectric generating stations
(GS) usually include a deep excavation adjacent to
the receiving waterbody and an associated tailrace
that requires contouring into that waterbody for the
efficient discharge of flow. These are often
constructed as one, which requires the use of a
large coffer dam intruding into the receiving water
body and displacing habitat for about two years.
The often lengthy installation and removal of the
coffer dam requires the use of silt curtains, and can
expose the waterbody to the risk of the release of
sediment or other deleterious substances.
6
Alternative Activities
Construction of a clear-span bridge that has no inwater component, or encroaches upon the stream
bank, or negatively affects riparian vegetation.
Refer to Ontario Operational Statement, “Clearspan bridges”.
Avoid direct disturbance to the streambed and
banks by digging bell holes on either side of the
watercourse, and then boring under the streambed.
Refer to Ontario Operational Statement, “Punch
and Bore Crossings”.
Use a sheet pile coffer dam. Footprint is relatively
small, and does not require the placement and
removal of granular or soil/clay materials into the
watercourse.
Phased construction of a GS can significantly
reduce the duration and extent of habitat disruption.
The deep excavation of the powerhouse can occur
as Phase 1, using the natural shoreline as a coffer
dam, which, depending upon the native shoreline
material, may require reinforcement with a sheet
steel piling or other material. Once the
powerhouse is ready, water can be released into
the pit to the same level as the receiving
waterbody. In Phase 2, an effective silt curtain
(heavy chains along bottom) can isolate the extent
of the tailrace, and then the tailrace can be
excavated in-water and the shoreline plug
removed. Timing of Phase 2 is critical to avoid the
sensitive life stages of native fishes, and have
regard to river flow conditions. This can reduce the
duration of any disruption from years, to months or
weeks, and reduce the extent of the disruption by
the width of the coffer dam at a minimum. In most
cases, the excavation of the tailrace will be no
more disruptive or require more mitigation than the
placement and removal of coffer dams.
Figure 1. Master Pathway PoE Diagram: Land-based activities.
Figure 2. Master Pathway PoE Diagram: In-water activities.
7
Figure 3. PoE Diagram 1 - Vegetation clearing.
8
Table 2. Mitigation measures based on PoE Diagram 1 - Vegetation clearing.
Link
1-1
1-2
1-3
1-4
1-5
1-6
1-7
1-8
1-9
Mitigation
Minimize riparian vegetation removals. If removal is unavoidable use proper clearing techniques
and protect retained vegetation.
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Seasonal timing to minimize impacts.
Use only specified amounts and types of fertilizer in areas draining to waterbodies. Avoid use of
chemical dust suppressants, pesticides and herbicides in areas draining to waterbodies.
Seasonal timing to minimize impacts.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Dispose or temporarily store all materials used or generated (e.g., organics, soils, woody debris,
temporary stockpiles, construction debris) during site preparation, construction and clean-up in a
manner that mitigates their entry to waterbody.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement of
existing instream structure such as large wood debris, boulders, or instream aquatic vegetation.
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
In-water silt curtains to contain suspended sediments.
Selective or phased vegetation removal or species management to maintain or reduce shade on
stream and provide specialized riparian communities or habitats. This may be desirable for the
management of certain species, such as Redside Dace, salmonids, or warmwater species at risk.
Use only specified amounts and types of fertilizer in areas draining to waterbodies. Avoid use of
chemical dust suppressants, pesticides and herbicides in areas draining to waterbodies.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
9
Figure 4. PoE Diagram 2 - Grading.
10
Table 3. Mitigation measures based on PoE Diagram 2 -Grading.
Link
2-1
2-2
2-3
2-4
2-5
2-6
2-7
Mitigation
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Dispose or temporarily store all materials used or generated (e.g., organics, soils, woody debris,
temporary stockpiles, construction debris) during site preparation, construction and clean-up in a
manner that mitigates their entry to waterbody.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth, etc.).
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
11
Figure 5. PoE Diagram 3 - Excavation.
12
Table 4. Mitigation measures based on PoE Diagram 3 - Excavation.
Link
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
Mitigation
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth, etc.).
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling pond, in-water silt curtains to contain
suspended sediments).
Energy dissipation measures.
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth, etc.).
Minimize riparian vegetation removals. If removal is unavoidable use proper clearing techniques
and protect retained vegetation.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Dispose or temporarily store all materials used or generated (e.g., organics, soils, woody debris,
temporary stockpiles, construction debris) during site preparation, construction and clean-up in a
manner that mitigates their entry to waterbody.
13
Figure 6. PoE Diagram 4 - Use of explosives.
Table 5. Mitigation measures based on PoE Diagram 4 - Use of explosives.
Link
4-1
4-2
4-3
4-4
4-5
4-6
Mitigation
Operational constraint for blasting. Implement requirements and limitations for the use of
confined explosives, in or near, fisheries waters.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
In-water silt curtains to contain suspended sediments.
Seasonal timing to minimize impacts.
Avoid impacts to fishes by excluding, moving, or frightening fishes away. Must be undertaken
using proper handling techniques and strategies that will avoid or minimize stress.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
In-water silt curtains to contain suspended sediments.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Refer to Guidelines for the Use of Explosives In or Near Canadian Fisheries Waters (Wright and Hopky
1998).
14
Figure 7. PoE Diagram 5 - Use of industrial equipment.
15
Table 6. Mitigation measures based on PoE Diagram 5 - Use of industrial equipment.
Link
5-1
5-2
5-3
5-4
5-5
5-6
5-7
5-8
5-9
16
Mitigation
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Seasonal timing to minimize impacts.
Avoid impacts to fishes by excluding, moving, or frightening fishes away. Must be undertaken
using proper handling techniques and strategies that will avoid or minimize stress.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth, etc.).
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
In-water silt curtains to contain suspended sediments.
Design and implement isolation/containment plan to isolate temporary in-water work zones to
maintain clean flow downstream/around the work zone at all times. The design should:
• use only clean materials free of suspendable matter for temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge (e.g., see dewatering discharge) so
as to prevent erosion and sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against the impacts of high flow
events during the work period.
• remove fish from isolated in-water work zones if necessary
Vehicle and equipment re-fuelling and maintenance shall be conducted away from the water.
Any part of equipment entering the water shall be free of fluid leaks and externally
cleaned/degreased to mitigate any deleterious substance from entering the water.
Vehicle and equipment re-fuelling and maintenance shall be conducted away from the water.
Any part of equipment entering the water shall be free of fluid leaks and externally
cleaned/degreased to mitigate any deleterious substance from entering the water.
Spill containment plan.
Figure 8. PoE Diagram 6 - Cleaning or maintenance of bridges or other structures.
Table 7. Mitigation measures based on PoE Diagram 6 - Cleaning or maintenance of bridges or
other structures.
Link
6-1
6-2
6-3
6-4
6-5
Mitigation
Seasonal timing to minimize impacts.
Containment plan to keep dust, particulate scrubbings, blast sand, air-borne contaminants, and
other potentially deleterious substances from entering the waterbody. This is used to avoid the
necessity of dewatering.
Spill containment plan.
Containment plan to keep dust, particulate scrubbings, blast sand, air-borne contaminants, and
other potentially deleterious substances from entering the waterbody. This is used to avoid the
necessity of dewatering.
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
17
Figure 9. PoE Diagram 7 - Riparian planting.
Table 8. Mitigation measures based on PoE Diagram 7 - Riparian planting
Link
7-1
7-2
7-3
7-4
7-5
7-6
18
Mitigation
Seasonal timing to minimize impacts.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth, etc.).
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Use only specified amounts and types of fertilizer in areas draining to waterbodies. Avoid use of
chemical dust suppressants, pesticides and herbicides in areas draining to waterbodies.
Selective or phased vegetation removal or species management to maintain or reduce shade on
stream and provide specialized riparian communities or habitats. This may be desirable for the
management of certain species, such as Redside Dace, salmonids, or warmwater species at
risk.
Selective or phased vegetation removal or species management to maintain or reduce shade on
stream and provide specialized riparian communities or habitats. This may be desirable for the
management of certain species, such as Redside Dace, salmonids, or warmwater species at
risk.
Figure 10. PoE Diagram 8 - Streamside livestock grazing.
Table 9. Mitigation measures based on PoE Diagram 8 - Streamside livestock grazing.
Link
8-1
8-2
8-3
8-4
Mitigation
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth, etc.).
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
19
Figure 11. PoE Diagram 9 - Marine seismic surveys.
Table 10. Mitigation measures based on PoE Diagram 9 - Marine seismic surveys.
Link
9-1
9-2
9-3
Mitigation
Seasonal timing to minimize impacts.
Avoid impacts to fishes by excluding, moving, or frightening fishes away. Must be undertaken
using proper handling techniques and strategies that will avoid or minimize stress.
Seasonal timing to minimize impacts.
Avoid impacts to fishes by excluding, moving, or frightening fishes away. Must be undertaken
using proper handling techniques and strategies that will avoid or minimize stress.
Seasonal timing to minimize impacts.
Refer to the Standard Operating Procedure “Statement of Canadian Practice with respect to the
Mitigation of Seismic Sound in the Marine Environment” at http://www.dfo-mpo.gc.ca/ oceanshabitat/oceans/im-gi/seismic-sismique/statement-enonce_e.asp .
20
Figure 12. PoE Diagram 10 - Placement of material or structures in water.
21
Table 11. Mitigation measures based on PoE Diagram 10 - Placement of material or structures
in water.
Link
10-1
10-2
10-3
10-4
10-5
10-6
22
Mitigation
Reduce or eliminate constriction of flow through structure design. Design and situate piers and
abutments to avoid or otherwise minimize encroachment into waterbody, and avoid sensitive
habitats. Design bridge or culvert to not affect existing or natural flow regimes. Design and
install culverts to prevent creation of barriers to fish movement, and maintain bankfull channel
functions and habitat functions to the extent possible, includes:
• embedment.
• re-instatement of low flow channel and native substrates.
• proper sizing, maintaining channel slope.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Figure 13. PoE Diagram 11 - Dredging.
23
Table 12. Mitigation measures based on PoE Diagram 11 - Dredging.
Link
11-1
11-2
11-3
11-4
11-5
11-6
11-7
11-8
24
Mitigation
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Design and implement isolation/containment plan to isolate temporary in-water work zones to
maintain clean flow downstream/around the work zone at all times. The design should:
• use only clean materials free of suspendable matter for temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge (e.g., see dewatering discharge) so
as to prevent erosion and sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against the impacts of high flow
events during the work period.
• remove fish from isolated in-water work zones if necessary.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Figure 14. PoE Diagram 12 - Water extraction.
Table 13. Mitigation measures based on PoE Diagram 12 - Water extraction.
Link
12-1
12-2
Mitigation
Design and implement isolation/containment plan to isolate temporary in-water work zones to
maintain clean flow downstream/around the work zone at all times. The design should:
• use only clean materials free of suspendable matter for temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge (e.g., see dewatering discharge) so
as to prevent erosion and sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against the impacts of high flow
events during the work period.
• remove fish from isolated in-water work zones if necessary.
Screens to prevent entrainment of fishes into water intakes.
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
Energy dissipation measures.
Seasonal timing to minimize impacts.
Screens to prevent entrainment of fishes into water intakes.
25
Figure 15. PoE Diagram 13 - Organic debris management.
26
Table 14. Mitigation measures based on PoE Diagram 13 - Organic debris management.
Link
13-1
13-2
13-3
13-4
13-5
13-6
13-7
Mitigation
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Seasonal timing to minimize impacts.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Seasonal timing to minimize impacts.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Stabilize exposed soils (targeted planting of specialized vegetation treatments, add structure to
steep slopes, use of commercial seed mats, perforated soil cloth).
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
27
Figure 16. PoE Diagram 14 - Wastewater management.
Table 15. Mitigation measures based on PoE Diagram 14 - Wastewater management.
Link
14-1
14-2
14-3
14-4
14-5
14-6
14-7
14-8
14-9
28
Mitigation
Stormwater management.
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
Energy dissipation measures.
Wastewater cooling strategies (e.g., cooling towers, ponds, sprinklers, underground piping).
Wastewater nutrient removal strategies (e.g., wastewater treatment facilities, constructed
wetlands, soil leaching systems).
Wastewater contaminant removal strategies (e.g., wastewater treatment facilities, constructed
wetlands, soil leaching systems).
Wastewater sterilization techniques (e.g., chemical, UV).
Increase dilution or dilution rate of effluent (e.g., discharge location, effluent diffuser).
Increase dilution or dilution rate of effluent (e.g., discharge location, effluent diffuser).
Increase dilution or dilution rate of effluent (e.g., discharge location, effluent diffuser).
Seasonal timing to minimize impacts.
Figure 17. PoE Diagram 15 - Addition or removal of aquatic vegetation.
29
Table 16. Mitigation measures based on PoE Diagram 15 - Addition or removal of aquatic
vegetation.
Link
15-1
15-2
15-3
15-4
30
Mitigation
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Seasonal timing to minimize impacts.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Design and implement isolation/containment plan to isolate temporary in-water work zones to
maintain clean flow downstream/around the work zone at all times. The design should:
• use only clean materials free of suspendable matter for temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge (e.g., see dewatering discharge) so
as to prevent erosion and sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against the impacts of high flow
events during the work period.
• remove fish from isolated in-water work zones if necessary.
In-water silt curtains to contain suspended sediments.
(Modified from “Change in timing duration and frequency of flow” (Clarke et al. 2008))
Figure 18. PoE Diagram 16 - Flow management.
31
Table 17. Mitigation measures based on PoE Diagram 16 - Flow management.
Link
16-1
16-2
16-3
16-4
16-5
32
Mitigation
Seasonal timing to minimize impacts.
Dam design or operation to allow passage and minimize risk for fish passing upstream or
downstream of a dam (e.g., downstream migration diversion methods, turbines that exhibit low
fish mortality, spillways designed to pass fish safely. Upstream migration via fish ladders, bypass
channels).
Dam design, operation or mitigation (e.g., destratification systems) to reduce or eliminate effects
upon downstream water chemistry, water temperature, total gas pressure, or flow regime.
Flow management (e.g., minimum flows, seasonal flow augmentation, flushing flows) for specific
aquatic habitat management goals or to mitigate other effects of flow management.
Stormwater management.
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Reduce or eliminate constriction of flow through structure design. Design and site piers and
abutments to avoid or otherwise minimize encroachment into waterbody, and avoid sensitive
habitats. Design bridge or culvert to not affect existing or natural flow regimes. Design and
install culverts to prevent creation of barriers to fish movement, and maintain bankfull channel
functions and habitat functions to the extent possible, includes:
• embedment.
• re-instatement of low flow channel and native substrates.
• proper sizing, maintaining channel slope.
Natural channel design principles used for new watercourse sections.
Flow management (e.g., minimum flows, seasonal flow augmentation, flushing flows) for specific
aquatic habitat management goals or to mitigate other effects of flow management.
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Natural channel design principles used for new watercourse sections.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Energy dissipation measures.
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Natural channel design principles used for new watercourse sections.
Energy dissipation measures.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Flow management (e.g., minimum flows, seasonal flow augmentation, flushing flows) for specific
aquatic habitat management goals or to mitigate other effects of flow management.
Figure 19. PoE Diagram 17 - Fish passage issues.
33
Table 18. Mitigation measures based on PoE Diagram 17 - Fish passage issues.
Link
17-1
17-2
17-3
17-4
17-5
17-6
17-7
17-8
17-9
17-10
17-11
17-12
17-13
34
Mitigation
Reduce or eliminate constriction of flow through structure design. Design and site piers and
abutments to avoid or otherwise minimize encroachment into waterbody, and avoid sensitive
habitats. Design bridge or culvert to not affect existing or natural flow regimes. Design and
install culverts to prevent creation of barriers to fish movement, and maintain bankfull channel
functions and habitat functions to the extent possible, includes:
• embedment.
• re-instatement of low flow channel and native substrates.
• proper sizing, maintaining channel slope.
Seasonal timing to minimize impacts.
Dam design or operation to allow passage and minimize risk for fish passing upstream or
downstream of a dam (e.g., downstream migration diversion methods, turbines that exhibit low
fish mortality, spillways designed to pass fish safely, upstream migration via fish ladders, bypass
channels).
Flow management (e.g., minimum flows, seasonal flow augmentation, flushing flows) for specific
aquatic habitat management goals or to mitigate other effects of flow management.
Screens to prevent entrainment of fishes into water intakes.
Seasonal timing to minimize impacts.
Dam design or operation to allow passage and minimize risk for fish passing upstream or
downstream of a dam (e.g., downstream migration diversion methods, turbines that exhibit low
fish mortality, spillways designed to pass fish safely, upstream migration via fish ladders, bypass
channels).
Flow management (e.g., minimum flows, seasonal flow augmentation, flushing flows) for specific
aquatic habitat management goals or to mitigate other effects of flow management.
Stormwater management.
Dam design, operation or mitigation (e.g., destratification systems) to reduce or eliminate effects
upon downstream water chemistry, water temperature, total gas pressure, or flow regime.
Stormwater management.
Dam design, operation or mitigation (e.g., destratification systems) to reduce or eliminate effects
upon downstream water chemistry, water temperature, total gas pressure, or flow regime.
Stormwater management.
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Seasonal timing to minimize impacts.
Seasonal timing to minimize impacts.
Seasonal timing to minimize impacts.
Flow management (e.g., minimum flows, seasonal flow augmentation, flushing flows) for specific
aquatic habitat management goals or to mitigate other effects of flow management.
Create additional or replacement critical or limiting habitats.
Natural channel design principles used for new watercourse sections.
Design and implement isolation/containment plan to isolate temporary in-water work zones to
maintain clean flow downstream/around the work zone at all times. The design should:
• use only clean materials free of suspendable matter for temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge (e.g., see dewatering discharge) so
as to prevent erosion and sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against the impacts of high flow
events during the work period.
• remove fish from isolated in-water work zones if necessary.
Avoid or minimize diversion of surface and groundwater drainage to or from a waterbody (do not
divert across watershed boundaries).
Figure 20. PoE Diagram 18 - Structure removal.
35
Table 19. Mitigation measures based on PoE Diagram 18 - Structure removal.
Link
18-1
18-2
18-3
18-4
18-5
18-6
18-7
18-8
36
Mitigation
Riparian vegetation plantings. Design and implement vegetation rehabilitation plan following
construction/disturbance to re-plant riparian vegetation to pre-construction or better condition
(e.g., trees for shade to cool water and provide overhead cover).
• usually includes re-instatement of native soils or replacement with topsoil/suitable planting
medium.
• may include soil/seedbank salvage, vegetation transplant or bio-engineering (e.g., live stakes,
cuttings) techniques.
• typically only native species compatible with site conditions are used.
Prohibit or limit access to banks or areas adjacent to waterbodies, to the extent required to
protect the structural integrity of banks or shorelines.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Containment plan to keep dust, particulate scrubbings, blast sand, air-borne contaminants, and
other potentially deleterious substances from entering the waterbody. This is used to avoid the
necessity of dewatering.
Adjust channel morphology to maintain appropriate hydraulics (e.g., addition of riffles to slow
upstream velocities; modification of width and/or depth to adjust velocities).
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Stabilize/reinforce stream banks using tree and shrub plantings, root wads, boulders, vortex
weirs, etc.
Rehabilitation of stream morphology and substrate to pre-disturbance condition or better.
Add/establish appropriate instream structure and cover for habitat, in such a way as to not
destabilize the channel through negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail the salvage and reinstatement
of existing instream structure such as large wood debris, boulders, or instream aquatic
vegetation.
Design and implement isolation/containment plan to isolate temporary in-water work zones to
maintain clean flow downstream/around the work zone at all times. The design should:
• use only clean materials free of suspendable matter for temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge (e.g., see dewatering discharge) so
as to prevent erosion and sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against the impacts of high flow
events during the work period.
• remove fish from isolated in-water work zones if necessary.
Treatment of dewatering (or other) discharge water by sediment settling ponds, filter bags, etc.
Energy dissipation measures.
Sediment and erosion controls to mitigate erosion of exposed soils to adjacent waterbody (e.g.,
erosion control fencing, fabrics, straw, straw bales, settling ponds).
Seasonal timing to minimize impacts.
In-water silt curtains to contain suspended sediments.
Appendix A: Mitigation measures to break the paths in the Pathways of Effects (PoE)
diagrams.
Mitigation Measures 1
O-Bl Operational constraint for blasting.
- Implement requirements and limitations for the use of confined
explosives, in or near, fisheries waters.
M-Veg Minimize riparian vegetation removals. If removal is
necessary use proper clearing techniques and protect retained
vegetation.
M-Chem Use only specified amounts and types of fertilizer in
areas draining to waterbodies. Avoid use of chemical dust
suppressants, pesticides and herbicides in areas draining to
waterbodies.
R-Veg Riparian vegetation plantings. Design and implement
vegetation rehabilitation plan following construction/disturbance
to re-plant riparian vegetation to pre-construction or better
condition (e.g., trees for shade to cool water and provide
overhead cover).
• usually includes re-instatement of native soils or replacement
with topsoil/suitable planting medium.
• may include soil/seedbank salvage, vegetation transplant or
bio-engineering (e.g., live stakes, cuttings) techniques.
• typically only native species compatible with site conditions are
used.
O-Acc Prohibit or limit access to banks or areas adjacent to
waterbodies, to the extent required to protect the structural
integrity of banks or shorelines.
M-ExM Dispose or temporarily store all materials used or
generated (e.g., organics, soils, woody debris, temporary
stockpiles, construction debris) during site preparation,
construction and clean-up in a manner that prevents their entry to
waterbody.
D-SWM Stormwater management.
D-Dr Avoid or minimize diversion of surface and groundwater
drainage to or from a waterbody (do not divert across watershed
boundaries).
R-IsC Add/establish appropriate instream structure and cover for
habitat, in such a way as to not destabilize the channel through
negative impacts to hydraulics. Match structure/substrate type
with previous or adjacent types where possible. This may entail
the salvage and reinstatement of existing instream structure such
as large wood debris, boulders, or instream aquatic vegetation.
Stressor Locations
(pathway)
4-1
1-1, 2-2, 3-9
1-2, 1-9, 7-4
1-3, 1-9, 3-2, 3-10, 5-3, 8-2,
13-5, 13-6, 15-1, 16-3, 18-1
1-1, 1-6, 2-1, 5-1, 8-1, 13-1,
13-4, 18-1
1-4, 2-2, 3-12
14-1, 16-2, 17-5, 17-6, 17-7
2-6, 3-1, 3-7, 14-1, 16-2, 177, 17-13
1-5, 2-3, 8-3, 10-4, 10-5, 106, 11-6, 11-8, 13-3, 13-5,
13-6, 15-1, 15-2, 16-5, 18-6
(cont’d)
37
Appendix A (cont’d): Mitigation measures to break the paths in the Pathways of Effects
(PoE) diagrams.
Mitigation Measures 1
R-BdSb Rehabilitation of stream morphology and substrate to
pre-disturbance condition or better.
D-C, D-Br Reduce or eliminate constriction of flow through
structure design. Design and site piers and abutments to avoid
or otherwise minimize encroachment into waterbody, and avoid
sensitive habitats. Design bridge or culvert to not affect existing
or natural flow regimes. Design and install culverts to prevent
creation of barriers to fish movement, and maintain bankfull
channel functions and habitat functions to the extent possible,
includes:
• embedment.
• re-instatement of low flow channel and native substrates.
• proper sizing, maintaining channel slope.
Adjust channel morphology to maintain appropriate hydraulics
(e.g., addition of riffles to slow upstream velocities; modification
of width and/or depth to adjust velocities).
R-ExS Stabilize exposed soils (targeted planting of specialized
vegetation treatments, add structure to steep slopes, use of
commercial seed mats, perforated soil cloth, etc.).
R-NCD Natural channel design principles used for new
watercourse sections.
R-Bk Stabilize/reinforce stream banks using tree and shrub
plantings, root wads, boulders, vortex weirs, etc.
Create additional or replacement critical or limiting habitats.
Selective or phased vegetation removal or species management
to maintain or reduce shade on stream and provide specialized
riparian communities or habitats. This may be desirable for the
management of certain species, such as Redside Dace,
salmonids, or warmwater species at risk.
M-TF Design and implement isolation/containment plan to
isolate temporary in-water work zones to maintain clean flow
downstream/around the work zone at all times. The design
should:
• use only clean materials free of suspendable matter for
temporary coffer dams.
• situate or otherwise manage flow withdrawal and discharge
(e.g., see dewatering discharge) so as to prevent erosion and
sediment release to the waterbody.
• ensure the work zone is stabilized to the extent practical against
the impacts of high flow events during the work period.
• remove fish from isolated in-water work zones if necessary.
See fish transfer (MFTr) and fish screens (MFSc) for managing
fishes.
Stressor Locations
(pathway)
10-2, 10-4, 11-1, 11-3, 11-5,
13-2, 16-5, 18-1, 18-3, 18-5
10-1, 16-2, 17-1
10-2, 10-3, 11-2, 16-3, 16-4,
16-5, 18-2
2-5, 3-3, 3-8, 5-3, 7-3, 8-4,
13-7
16-2, 16-3, 16-4, 17-12
1-6, 2-4, 3-3, 4-5, 5-3, 7-3,
8-4, 11-1, 11-4, 13-7, 16-3,
18-1, 18-4
17-11
1-8, 7-5, 7-6
5-6, 11-7, 12-1, 15-3, 17-12,
18-7
(cont’d)
38
Appendix A (cont’d): Mitigation measures to break the paths in the Pathways of Effects
(PoE) diagrams.
Mitigation Measures 1
M-DwD Treatment of dewatering (or other) discharge water by
sediment settling ponds, filter bags, etc.
M-DwD Energy dissipation measures.
M-FSc Screens to prevent entrainment of fishes into water
intakes.
M-ESC Sediment and erosion controls to prevent erosion of
exposed soils to adjacent waterbody (e.g., erosion control
fencing, fabrics, straw, straw bales, settling ponds).
In-water silt curtains to contain suspended sediments.
O-TW Seasonal timing to minimize impacts.
M-FTr Avoid impacts to fishes by excluding, moving, or
frightening fishes away. Must be undertaken using proper
handling techniques and strategies that will avoid or minimize
stress.
M-Eqp Vehicle and equipment re-fuelling and maintenance shall
be conducted away from the water. Any part of equipment
entering the water shall be free of fluid leaks and externally
cleaned/degreased to prevent any deleterious substance from
entering the water.
M-Spl Spill containment plan.
M-WSCon Containment plan to keep dust, particulate
scrubbings, blast sand, air-borne contaminants, and other
potentially deleterious substances from entering the waterbody.
This is used to avoid the necessity of dewatering.
Wastewater cooling strategies (e.g., cooling towers, ponds,
sprinklers, underground piping).
Wastewater nutrient removal strategies (e.g., wastewater
treatment facilities, constructed wetlands, soil leaching systems).
Wastewater contaminant removal strategies (e.g., wastewater
treatment facilities, constructed wetlands, soil leaching systems).
Wastewater sterilization techniques (e.g., chemical, UV).
Increase dilution or dilution rate of effluent (e.g., discharge
location, effluent diffuser).
Dam design or operation to allow passage and minimize risk for
fish passing upstream or downstream of a dam (e.g.,
downstream migration diversion methods, turbines that exhibit
low fish mortality, spillways designed to pass fish safely,
upstream migration via fish ladders, bypass channels).
Stressor Locations
(pathway)
1-7, 3-6, 6-4, 6-5, 12-1, 141, 18-7
3-5, 12-1, 14-1, 16-3, 16-4,
18-7
12-1, 12-2, 17-3
1-6, 1-9, 2-1, 2-7, 3-2, 3-4,
3-11, 4-2, 4-4, 4-6, 5-4, 6-4,
6-5, 7-2, 13-3, 13-6, 18-7
1-7, 3-4, 4-2, 4-4, 5-5, 15-4,
18-8
1-1, 1-2, 4-3, 5-2, 6-1, 7-1,
9-1, 9-2, 9-3, 12-1, 13-1, 134, 14-9, 15-1, 16-1, 17-2,
17-4, 17-8, 17-9, 17-10, 187
4-3, 5-2, 9-1, 9-2
5-7, 5-8
5-9, 6-2
6-1, 6-3, 18-1
14-2
14-3
14-4
14-5
14-6, 14-7, 14-8
16-1, 17-2, 17-4
(cont’d)
39
Appendix A (cont’d): Mitigation measures to break the paths in the Pathways of Effects
(PoE) diagrams.
Mitigation Measures 1
Dam design, operation or mitigation (e.g., destratification
systems) to reduce or eliminate effects upon downstream water
chemistry, water temperature, total gas pressure, or flow regime.
Flow management (e.g., minimum flows, seasonal flow
augmentation, flushing flows) for specific aquatic habitat
management goals or to mitigate other effects of flow
management.
1
Stressor Locations
(pathway)
16-1, 17-5, 17-6
16-1, 16-2, 16-5, 17-2, 17-4,
17-10
Bolded code at the beginning of each Mitigation Measure is the MTO code for the corresponding MTO
Mitigation Action. These are included to facilitate comparisons by reviewers.
40
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