bank material pre-hydroelectric development · table 6.3.5-15: shoreline debris accumulation and...
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Southern IndianTerrestrial
Region
BradshawTerrestrial
Region
Upper ChurchillTerrestrial
Region
LongSpruce
G.S.KettleG.S.
MissiFalls
NorthKnifeLake
KnifeLake
South
Kelsey
Nonsuch
Willbeach
Wivenhoe
Luke
RapidsKettle
Tidal
Digges
Bylot
Lampray
Back
M'Clintock
Kellett
Herchmer
Thibaudeau
Jacam
Namaypin
TetroeMuskegoLake
L
LakeBarnes
Roe Lake
BaldockLake
BreastPartridgeL
Lake
LakeAshley
Starrett
LakePennie
LakeShethanei
Pott
Lake
Noguy
Aiken
Lake
LakeLifebuoy
Lake
Legary
Paragon
Lake
WalfordLake
Lake
Wishart
Lake
Oldman
Currie
Lake
Wood
NorthernLake
LakeThorsteinson
Gauer
River
Lake
LakeJensen
Warnews
R
Meridian
LRock
Strong LakeOrr
Odei
Lake
LPearson
Blank
R
LakeStone
Campbell
White
Lake
Lake
KiaskL
Handle
LakeWernham
HoodLake
Lake
Indian
LakeSmall
HibbertLake
KnifeheadLake
LakeLake
Blyth
North
Knife
Drift
L R
QuinnLake
River
Lake
LakeLovat
TraerLake
Beganili
AllanLake
Lake
PisewLake
EtawneyLake
Little
Naykow
River
Lake
Fidler
Lake
SetteeLake
ChristieL
LakePelletier
Clay AsseanLake
River
LakeHunting
River
Hunting
Lake
Lake
BissetCaldwell
LakeThomasL
Holmes
Lake
Churchill
Solmundsson
Lake
LakeKotchapaw
Buckland
KnifeSouth
Lake
North
Fabas
L
Lake
Thousin
LakeNichol
NaresLake
Condie
EinarsonLake
Lake
GylesLake
MinikwakunisLake
Beaver
LakeFreeman
River
R
Bieber
Assaikwatamo
Hale
Lake
Waskaiowaka
River
Lake
Aiken
Split
FoxL
LakeCrying
L
Little
RecluseLake
R
LakeLake
Embleton
L
Billard
Hogg
MountainRapids
TheFours
River
LakeComeau
Gersham
Creek
Matonabee
Skromeda
Knife
Creek
South
KnightLake
Mack
Braden
L
Lake
RapidsSwallow
Churchill
LimestoneLake
Nelson
BirthdayRapids
River Kettle
LakeButnau
LakeJean
GullLake
Wasagamow
L
River
Lakes
Bradshaw
Rapids
ChurchillRiver
Lake CacheKilnabad Rapids
LakeWise
Herriot
Knife
DickensLake
TeepeeFalls
Langille
River
Creek
Nowell
River
Lake
LakeLofthouse
Heppell
Creek
BishopLake
MunkLRankine
Laforte
Crosswell
Bad
Lake
TurcotteDeer L
Deer
Whiting
MistakeL
L
Lake
Whitecap
Cygnet
Cygnet Little
LL
Limestone
AtkinsonL
KettleLake
Wilson
R
River
LMyre
Strobus LWeir
Lake
LongLake
L
LakeOwl
Fly
River
River
LandingHead
Ck
Red PlaceRapids
Running
Rapids
RiverCreek
HolcraftL
BayButton
Warkworth
LimestoneRapids
River
Dog
Ck
Moose
Horn
Lost
Weir
Kettle
Creek
North
Fox LakeCree Nation
York FactoryFirst Nation
War LakeFirst Nation
Ilford (NAC)
KeeyaskG.S.
280
280
280280
280
280
Gillam
Churchill
1.0
17-JUN-15
ECOSTEM Ltd.
Created By: snitowski - B Size Portrait BTB - MAR 2015 Scale: 1:880,000
19-NOV-15
File Location: Z:\Workspaces\RCEA\Habitat Regulated System\Bank Material Upper Churchill Region Pre.mxd
Hudson Bay
Thompson
Winnipeg
Churchill
Regional Cumulative Effects Assessment
NAD 1983 UTM Zone 14N
0 10 20 Kilometers
0 8 16 Miles
DATA SOURCE:
DATE CREATED:
CREATED BY:
VERSION NO:
REVISION DATE:
QA/QC:
COORDINATE SYSTEM:
Manitoba Hydro; Government of Manitoba; Government of Canada;ECOSTEM Ltd. Bank Material
Pre-Hydroelectric DevelopmentUpper Churchill Terrestrial Region
LegendTerrestrial RegionRCEA Region of Interest
Bank MaterialBedrockClayClay on BedrockClay on Low BedrockGravel
HumanPeatSandSand on ClayUnknown
Post-Hydroelectric InfrastructureGenerating Station (Existing)
Generating Station (Under Construction)Transmission Line (Existing)Transmission Line (Under Construction)HighwayRail
Map 6.3.5-10
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-285
Table 6.3.5-12: Bank Material Composition of the Pre-Hydroelectric Development Classified Shorelines in the Upper Churchill Terrestrial Region of the Taiga Shield Ecozone
Bank Material Length (km) Percentage of Mapped Shoreline
Bedrock 8 1
Clay on low bedrock 445 49
Clay on bedrock 34 4
Clay 156 17
Sand 89 10
Sand on clay 42 5
Gravel 127 14
Human 0 0
Total 900 100
Total unmapped shoreline 357
Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding.
Table 6.3.5-13: Shore Zone Wetland Composition of the Pre-Hydroelectric Development Classified Shorelines in the Upper Churchill Terrestrial Region of the Taiga Shield Ecozone
Shore Zone Wetland Type Length (km) Percentage of Mapped Shoreline
Narrow marsh 13 1
Moderately wide marsh 14 2
Wide marsh 3 0
Riparian peatland 111 12
Mixture of riparian peatland and narrow marsh 7 1
Mixture of riparian peatland and moderately-wide marsh 15 2
Mixture of riparian peatland and wide marsh 6 1
Open water 731 81
Total 900 100
Total unmapped shoreline 357 Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding.
Tadoule
Lake
LakeShethanei
Fox LakeCree Nation
York FactoryFirst Nation
War LakeFirst Nation
Ilford (NAC)
Southern IndianTerrestrial
Region
BradshawTerrestrial
RegionUpper Churchill
TerrestrialRegion
Southern IndianTerrestrial
Region
KelseyG.S.
LongSpruce
G.S.KettleG.S.
Lake
Namaypin
Lake
L
Tetroe
Odei
Hunter R
MuskegoLake
L
LakeBarnes
Roe Lake
BaldockLake
BreastPartridgeL
Lake
LakeAshley
Starrett
LakePennie
Lake
Pott
Lake
Noguy
Aiken
Lake
LakeLifebuoy
Lake
Legary
Paragon
Lake
WalfordLake
Lake
Wishart
Lake
Oldman
Currie
Lake
Wood
NorthernLake
LakeThorsteinson
Gauer
River
Lake
LakeJensen
Warnews
R
Meridian
LRock
Strong
Lake
LakeOrr
Odei
Lake
LPearson
Blank
R
LakeStone
Campbell
White
Lake
Lake
KiaskL
Handle
LakeWernham
HoodLake
Lake
Indian
LakeSmall
HibbertLake
KnifeheadLake
LakeLake
Blyth
North
Knife
Drift
L R
QuinnLake
River
LakeLovat
TraerLake
Beganili
AllanLake
Lake
PisewLake
EtawneyLake
Little
Naykow
River
Lake
Fidler
Lake
SetteeLake
ChristieL
LakePelletier
Clay
R River
AsseanLake
River
LakeHunting
River
Hunting
Lake
Lake
BissetCaldwell
LakeThomasL
Holmes
Lake
Churchill
Solmundsson
Lake
LakeKotchapaw
Buckland
KnifeSouth
Lake
North
Fabas
L
Lake
Thousin
LakeNichol
NaresLake
Condie
EinarsonLake
Lake
GylesLake
MinikwakunisLake
Beaver
LakeFreeman
River
R
Bieber
Assaikwatamo
Hale
Lake
Waskaiowaka
River
BaySinclair
Aiken
Split
FoxL
LakeCrying
L
Little
RecluseLake
R
LakeLakeEmbleton
L
Billard
Hogg
MountainRapids
TheFours
River
LakeComeau
Gersham
Creek
Matonabee
Skromeda
Knife
Creek
South
KnightLake
Mack
Braden
L
Lake
RapidsSwallow
Churchill
LimestoneLake
Nelson
BirthdayRapids
War
River Kettle
RiverLake
LakeButnau
LakeJean
GullLake
Wasagamow
L
River
Lakes
Bradshaw
Rapids
ChurchillRiver
Lake CacheKilnabad Rapids
LakeWise
Herriot
Knife
DickensLake
TeepeeFalls
Langille
River
Creek
Nowell
River
Lake
LakeLofthouse
Heppell
Creek
BishopLake
MunkLRankine
Laforte
Crosswell
Bad
Lake
TurcotteDeer L
Deer
Whiting
MistakeL
L
Lake
Whitecap
Cygnet
Cygnet Little
LL
Limestone
Hawes
Atkinson
Lake
L
KettleLake
Wilson
R
River
LMyre
Strobus LWeir
Lake
LongLake
L
LakeOwl
Fly
River
River
LandingHead
Ck
Red PlaceRapids
Running
Rapids
RiverCreek
HolcraftL
BayButton
LFarnworth
Warkworth
Alston
LimestoneRapids
River
Dog
Ck
Moose
Horn
Lost
Weir
Kettle
AnglingCreek
North
KeeyaskG.S.
280
280
280280
280
280
280
Gillam
1.0
14-OCT-15
ECOSTEM Ltd.
Created By: snitowski - B Size Portrait BTB - MAR 2015 Scale: 1:900,000
19-NOV-15
File Location: Z:\Workspaces\RCEA\Habitat Regulated System\Shore Wetland Upper Churchill Region Pre.mxd
Hudson Bay
Thompson
Winnipeg
Churchill
Regional Cumulative Effects Assessment
NAD 1983 UTM Zone 14N
0 10 20 Kilometers
0 8 16 Miles
DATA SOURCE:
DATE CREATED:
CREATED BY:
VERSION NO:
REVISION DATE:
QA/QC:
COORDINATE SYSTEM:
Legend Post-Hydroelectric InfrastructureGenerating Station (Existing)
HighwayRailTransmission Line (Existing)Transmission Line (UnderConstruction)
Manitoba Hydro; Government of Manitoba; Government of Canada;ECOSTEM Ltd. Shore Zone Wetland Type
Pre-Hydroelectric Development Upper Churchill Terrestrial Region
RCEA Region of Interest Generating Station (UnderConstruction)
Terrestrial Region
Shore Wetland ClassRiparian PeatlandModerately Wide to Wide MarshMarshScattered Marsh
Shallow WaterUnknown
Map 6.3.5-11
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-287
Table 6.3.5-14: Offshore wetland Composition of the Pre-Hydroelectric Development Classified Shorelines in the Upper Churchill Terrestrial Region of the Taiga Shield Ecozone
Offshore Wetland Type Length (km) Percentage of Mapped Shoreline
Narrow marsh 1 0
Moderately wide marsh 3 0
Pondweed 32 4
None 864 96
Total 900 100
Total unmapped shoreline 357 Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding.
Table 6.3.5-15: Shoreline Debris Accumulation and Distribution along the Pre-Hydroelectric Development and Existing Environment Classified Shorelines in the Upper Churchill Terrestrial Region of the Taiga Shield Ecozone, for Overlapping Areas
Shoreline Debris Accumulation
Shore Segment Coverage
Pre-Hydroelectric Development Existing Environment
Length (km)
Percentage of Length
Length (km)
Percentage of Length
None - 253 100 170 100
Total 253 100 170 100
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-288
AFTER HYDROELECTRIC DEVELOPMENT
Terrestrial Habitat Composition
Infrastructure development during the hydroelectric development period directly removed approximately 58 ha, or less than 0.01%, of native terrestrial habitat in the Upper Churchill Terrestrial Region (Intactness, Section 6.2.6.1.1). Former areas of riverbed regularly exposed by dewatering resulting from the CRD increased land area by an estimated 12,031 ha (note that land area increase is a function of the water levels on the day the waterbodies were mapped). The indirect effects of all human infrastructure development and dewatering were estimated to have altered an additional 5,877 ha, or 0.4%, of terrestrial habitat as of 2013 (see Section 6.3.1.5.1. for discussion of the potential indirect effects).
Hydroelectric development contributed all of the direct and indirect habitat effects in this terrestrial region. Transmission line development was responsible for all of the off-system native habitat loss. Visual inspection of the classified satellite imagery mapping suggested that the coarse habitat types most affected by transmission line development in this terrestrial region included open needleleaf treed with herb-shrub understorey on shallow to thin peatland and open to semi-closed needleleaf treed on shallow peatland to mineral. The direct and indirect effects of transmission lines on terrestrial habitat were less than from other human footprint types since the associated effects were generally limited to clearing taller vegetation, whereas other footprint types typically included soil excavation and a permanent infrastructure cover.
Dewatered area mapping produced from aerial photography taken eight years after initial dewatering was available for approximately 32% of the dewatered area in the Upper Churchill Terrestrial Region. These data indicated that the early terrestrial habitat composition of the newly exposed riverbed areas was predominantly low vegetation growing on the exposed mineral terraces and riverbed (Table 6.3.6-16). Most of the remaining dewatered area was a mixture of barren areas, and areas vegetated with a mixture of low vegetation, and sparse tall shrub vegetation. For the existing environment, unusually high water levels in the available imagery obscured the further vegetation development that may have occurred between 1982 and 2015. A series of photos acquired from a helicopter on June 23, 2015 at the junction of the Gauer and Churchill rivers suggested that the tall shrub band continued to expand into the dewatered areas in these locations, while large zones of low shrub and graminoid vegetation persist (Photos 6.3.5-1A and B).
Based on the areas in the terrestrial region where available mapping extended 100 metres inland of the dewatered zone, the most common land cover type indirectly affected by dewatering included needleleaf treed vegetation on mineral soil or thin peatland, occasionally in mixtures with tall shrubs (Table 6.3.5-17). Lower-lying shallow and deep peatlands would be more susceptible to indirect effects, but these made up only 8% of the inland cover in the terrestrial region.
Medium-term indirect effects from dewatering on inland habitat were expected to be limited because it was already an upland vegetation type. Over the longer term, the edge habitat may disappear or shift to the new shoreline location as treed vegetation develops in the dewatered area.
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-289
Table 6.3.5-16: Composition of Dewatered Areas in the Upper Churchill and Southern Indian Terrestrial Regions of the Taiga Shield Ecozone in 1982
Cover Type Upper Churchill Terrestrial Region
Southern Indian Terrestrial Region
Barren on mineral 13 12
Barren on mineral bank 1 1
Barren on mineral terrace 3 4
Barren on outcrop 0 -
Low on mineral 54 43
Low on mineral bank 5 0
Low on mineral terrace 20 6
Tall shrub on mineral 0 1
Tall shrub on mineral terrace - 0
Tall shrub/ Low on mineral bank 0 -
Tall shrub/ Low on mineral terrace 1 -
Tall shrub/ Low on mineral 1 19
Tall shrub/ Low on mineral bank 0 0
Tall shrub/ Low on mineral terrace 0 12
Tall shrub/ Low on wet peat 2 -
Total mapped area (ha) 3,894 1,929 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-290
Source: Darryl Hedman, June 23, 2015
Photo 6.3.5-1: Examples of Vegetation Development in Dewatered Areas in the Upper Churchill Terrestrial Region of the Taiga Shield Ecozone in 2015
A.
B.
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-291
Table 6.3.5-17: Composition of Land Cover 100 metres Inland of Dewatered Areas in the Upper Churchill and Southern Indian Terrestrial Regions of the Taiga Shield Ecozone in 1982
Land Cover Type Upper Churchill Southern Indian
Barren on mineral 1 1
Barren on mineral bank - 0
Broadleaf mixed on mineral or thin peat - 1
Broadleaf on mineral or thin peat - 0
Needleleaf mixed on mineral or thin peat 7 15
Needleleaf on mineral or thin peat 74 71
Needleleaf on mineral or thin peat bank 4 9
Needleleaf on shallow peat 4 2
Needleleaf on wet peat - 0
Needleleaf/ Tall shrub on mineral or thin peat 8 -
Needleleaf/ Tall shrub on shallow peat 0 -
Tall shrub on mineral - 0
Tall shrub/ Low on mineral terrace 0 -
Low on mineral 0 0
Total Inland Area (ha) 1,859 1,361 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
Ecosystem Diversity
Virtually all of the ecosystem diversity effects in the Upper Churchill Terrestrial Region were related to hydroelectric development, which comprised approximately 100% of the very small human development in the terrestrial region as of 2013.
Transmission lines comprised less than 1% of the human footprint in the terrestrial region as of 2013. Transmission lines tend to affect a wide variety of habitat types than other types of linear infrastructure because their construction is less constrained by terrain.
Due to the extremely limited extent of the human footprint outside of the large river system shore zone, it was unlikely that habitat loss during the hydroelectric development period had any substantial effects on ecosystem diversity with the possible exception of regulated system shoreline ecosystem types affected by dewatering (see Shoreline Ecosystems section below). While the newly developing terrestrial habitat in dewatered areas may eventually offset some of the effects of inland developments occurring on mineral sites as they revegetate, they would not offset effects on inland wetland habitat types.
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-292
Wetland Function
As indicated earlier, wetland function metrics were based on the detailed terrestrial habitat mapping, which was only available for a small portion of this terrestrial region.
The Churchill transmission line extending through the region likely affected wetlands inland of the lower Churchill River shore zone, but this feature fell outside of the mapped area. The transmission line would have only cleared tall vegetation, and in most cases would have simply altered wetlands without removing them. Dewatering in the lower Churchill River also may have indirectly affected wetlands adjacent to or near the river banks because of a lowered water table. While detailed mapping was not available to quantify these effects, they are expected to be minimal on regional wetland function due to the small size of the human footprint at the regional level.
Shoreline Ecosystems
Most effects on shoreline ecosystems in this terrestrial region were due to dewatering resulting from the CRD (the Churchill transmission line and winter roads were responsible for the remaining effects). Examples of changes were upland and shore zone vegetation colonization of the dewatered area, and more woody and shade tolerant vegetation in the highest elevations of the former shore zone due to a lower water table.
Dewatering altered shorelines along the entire length of the lower Churchill River in this terrestrial region. Total regional surface water area decreased from approximately 223,902 ha to 211,881 ha (see Section 6.3.1.5.5 for the limitations of these data). Regulated system shoreline length decreased from 1,258 to 1,105 km due to the merging of several islands in Northern Indian Lake, reducing shoreline complexity.
Dewatered area mapping from photography acquired eight years following dewatering indicated that low vegetation and tall shrub cover were beginning to expand outward from the pre-CRD waterline, and tall shrubs were beginning to establish on the new permanently to periodically exposed terraces and riverbeds. Helicopter photography acquired in 2015 confirmed this tall shrub expansion trend in the photographed locations.
For the RCEA, one or more existing environment shore zone attributes were mapped for 16% of the shoreline from high resolution satellite imagery provided by Bing®. Compared to 2015 photos acquired during lower water levels, water levels in this remote sensing were unusually high compared to the immediately prior median levels. Existing environment shoreline mapping was only available for a portion of Thorsteinson Lake, the Gauer River, and part of the Churchill River mainstem between Partridge Breast and Northern Indian lakes. These were the only reaches where satellite imagery of sufficient resolution was available.
The small proportion of shoreline mapped between Partridge Breast and Northern Indian lakes was likely not representative of the entire reach dominated by larger riverine lakes. This conclusion was based on the differences in pre-development bank material within and outside of the shoreline mapped for existing environment (see Map 6.3.5-10). Another limitation of the existing environment shoreline classification was that water elevations were unusually high in the available remote sensing, obscuring most of the
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-293
beaches and shore zone in the overlapping areas. Based on 2015 photos acquired during lower water levels, the degree of vegetation development in areas covered by water in the satellite imagery indicated that the following results likely do not represent typical post-CRD conditions in the mapped portions of the river system.
Reaches with both pre-hydroelectric development and existing environment shore zone mapping for at least one attribute comprised 16% of shoreline length. All of the following results that compare existing environment with pre-hydroelectric development values are based on the areas that have both pre-hydroelectric development and existing environment shore zone mapping (this includes all of the existing environment mapping), the spatial extent for which varies with attribute (e.g., shore zone wetland available for 16% of shoreline, bank material for 15%).
Hydroelectric development effects on waterbodies included decreasing total surface water area by approximately 12,021 ha, or 34%, and decreasing total shoreline length from 1,258 km to 1,105 km, or by 12%.
The amount of clay bank decreased by about 123 km, or to 17% of shoreline length (Table 6.2.3-18; Map 6.2.3-12; bank material mapped for 15% of the shoreline). Sand banks disappeared and gravel banks decreased to 3% of the shoreline, while peat banks increased from nothing to about 138 km in total (80% of shoreline length). The increase in peat banks was a result of the waterline shifting onto peatlands in the available digital imagery. This apparent increase was likely due to the unusually high water elevations at the time the remote sensing was acquired. In this imagery, water has either inundated nearshore pre-CRD peatlands, or inundated peatlands that have begun to encroach onto the dewatered banks and beaches in the decades following dewatering.
Shoreline with low banks substantially decreased in length and proportion (220 to 33 km; Table 6.3B-9). Low to moderate and moderate bank heights virtually disappeared in the terrestrial region after CRD, but shoreline with no bank height increased substantially in length (0 to 138 km). No banks were associated with peat bank materials, which also increased considerably. The caveat described for bank material also applies to bank height.
Clay, sand and gravel beaches were reduced considerably in areas with pre-hydroelectric development and existing environment mapping (Table 6.3B-10). There was a substantial increase in peat beaches, from zero to 147 km (86%) of the mapped shoreline. Peat beaches were generally the nearshore portions of flooded peatlands, likely resulting from the unusually high water elevations in the remote sensing used for the mapping.
Wide beaches were no longer present along the mapped shoreline where beaches were detectable (Table 6.3B-9). The remaining beaches were an even mixture of low and moderate width.
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-294
Table 6.3.5-18: Bank Material Composition of the Pre-Hydroelectric Development and Existing Environment Classified Large River Shorelines of the Upper Churchill Terrestrial Region for Overlapping Areas
Bank Material
Pre-Hydroelectric Development Existing Environment
Length (km)
Percentage of Mapped Shoreline
Length (km)
Percentage of Mapped Shoreline
Bedrock 0 0 0 0
Clay on low bedrock 113 45 26 15
Clay on bedrock 2 1 1 0
Clay 35 14 2 1
Sand 33 13 - -
Sand on clay 3 1 - -
Gravel 66 26 5 3
Peat - - 138 80
Total 253 100 171 100 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
BradshawTerrestrial
Region
Upper ChurchillTerrestrial
Region
Southern IndianTerrestrial
Region
Fox LakeCree Nation
York FactoryFirst Nation War Lake
First NationIlford (NAC)
TataskweyakCree Nation
LongSpruce
G.S.KettleG.S.
KeeyaskG.S.
280
280
280
280
280
MissiFalls
NorthKnifeLake
KnifeLake
South
York Landing
Nonsuch
Willbeach
Wivenhoe
Luke
RapidsKettle
Tidal
Digges
Bylot
Lampray
Back
M'Clintock
Kellett
Herchmer
Thibaudeau
Jacam
Namaypin
TetroeMuskegoLake
L
LakeBarnes
Roe Lake
BaldockLake
BreastPartridgeL
Lake
LakeAshley
Starrett
LakePennie
Lake
LakeShethanei
Pott
Lake
Noguy
Aiken
Lake
LakeLifebuoy
Lake
Legary
Paragon
Lake
WalfordLake
Lake
Wishart
Lake
Oldman
Currie
Lake
Wood
NorthernLake
LakeThorsteinson
Gauer
River
Lake
LakeJensen
Warnews
R
Meridian
LRockOrr
Lake
LPearson
Blank
R
LakeStone
Campbell
White
Lake
Lake
KiaskL
Handle
LakeWernham
HoodLake
Lake
Indian
LakeSmall
HibbertLake
KnifeheadLake
LakeLake
Blyth
North
Knife
Drift
L R
QuinnLake
River
NeffSteel
LakeLake
LakeLovat
TraerLake
Beganili
AllanLake
Lake
PisewLake
EtawneyLake
Little
Naykow
River
Lake
Fidler
Lake
SetteeLake
ChristieL
LakePelletier
Clay AsseanLake
River
LakeHunting
River
Hunting
Lake
Lake
BissetCaldwell
LakeThomasL
Holmes
Lake
Churchill
Solmundsson
Lake
LakeKotchapaw
Buckland
KnifeSouth
Lake
North
Fabas
L
Lake
Thousin
GreatIsland
LakeNichol
NaresLake
Condie
EinarsonLake
Lake
GylesLake
MinikwakunisLake
Beaver
LakeFreeman
River
R
Bieber
Assaikwatamo
Hale
Lake
Waskaiowaka
River
Lake
Split
FoxL
LakeCrying
L
Little
RecluseLake
R
LakeLakeEmbleton
L
Billard
Hogg
MountainRapids
TheFours
River
LakeComeau
Gersham
Creek
Matonabee
Skromeda
Knife
Lake
Creek
South
KnightLake
Mack
Braden
L
Lake
RapidsSwallow
Churchill
LimestoneLake
NelsonBirthday
RapidsLake
Butnau
LakeJean
GullLake
Wasagamow
L
River
Lakes
Bradshaw
Rapids
ChurchillRiver
Lake CacheKilnabad Rapids
LakeWise
Herriot
Knife
DickensLake
TeepeeFalls
Langille
River
Creek
Nowell
Dymond
River
Lake
LakeLofthouse
Heppell
Creek
BishopLake
MunkLRankine
Laforte
Crosswell
Bad
Lake
TurcotteDeer L
Deer
Whiting
MistakeL
L
Lake
Whitecap
Cygnet
Cygnet Little
LL
Limestone
Stephens
KettleLake
Wilson
R
Lake
River
LMyre
Strobus LWeir
Lake
LongLake
L
LakeOwl
Fly
River
River
LandingHead
Ck
Red PlaceRapids
Running
Rapids
RiverCreek
HolcraftL
BayButton
L
Warkworth
LimestoneRapids
River
Dog
Ck
Moose
Horn
Lost
Weir
Kettle
Creek
North
Gillam
Churchill
1.0
17-JUN-15
ECOSTEM Ltd.
Created By: snitowski - B Size Portrait BTB - MAR 2015 Scale: 1:880,000
19-NOV-15
File Location: Z:\Workspaces\RCEA\Habitat Regulated System\Bank Material Upper Churchill Region Post.mxd
Hudson Bay
Thompson
Winnipeg
Churchill
Regional Cumulative Effects Assessment
NAD 1983 UTM Zone 14N
0 10 20 Kilometers
0 8 16 Miles
DATA SOURCE:
DATE CREATED:
CREATED BY:
VERSION NO:
REVISION DATE:
QA/QC:
COORDINATE SYSTEM:
Manitoba Hydro; Government of Manitoba; Government of Canada;ECOSTEM Ltd. Bank Material
Post-Hydroelectric Development Upper Churchill Terrestrial Region
LegendTerrestrial RegionRCEA Region of Interest
BankBedrockClayClay on BedrockClay on Low BedrockGravel
PeatUnknown
InfrastructureGenerating Station (Existing)Generating Station (Under Construction)Transmission Line (Existing)Transmission Line (Under Construction)HighwayRail
Map 6.3.5-12
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-296
While vegetation colonized some of the initially dewatered land areas, high water levels in the imagery obscured most of the shore zone. Typical shore zone vegetation, or even vegetated beaches, were not apparent along the mapped lower Churchill River shoreline in 2013. Riparian peatland and riparian peatland mixture with marsh in the various size classes was reduced from about 53 to about 26 km of shoreline (Table 6.3.5-19), or from about 21% to about 15% of shoreline length (Table 6.3.5-19; Map 6.3.5-13). Open water was reduced from 79% of the shoreline to 17%, while peatland increased from zero to 66% of the shoreline.
In offshore areas, occasional, and continuous marsh in all size classes increased from virtually zero to 37 km (21%) in the existing environment, while pondweed was not present on the mapped shoreline (Table 6.3.5-20). High water levels may have obscured offshore pondweed beds, and some of the offshore marsh may actually be inundated terrestrial vegetation, as suggested by the recent helicopter photos.
Shoreline with tall shrub bands increased slightly in the existing environment mapping (Table 6.3B-13). Narrow tall shrub zones increased by 16%. Although the length of shore occupied by moderately wide tall shrub zones did not increase, its proportion did (2% increase) due to the decreased shoreline length. It is uncertain if these tall shrubs would have been part of the shore zone under typical post-CRD water elevations, but rather may be inundated tall shrubs that were establishing in the dewatered zone.
No shoreline debris was identified along the mapped existing environment shoreline (Table 6.3.5-15; Map 6.3.5-14).
Shore zone habitat composition in 2015 likely reflected the unusually high water elevations in the imagery. The high amounts of peatland shoreline and offshore marsh compared to pre-development conditions in this portion of the river may reflect temporary inundation of peatlands, shrubs and/or marsh that had expanded in response to extended periods of low water levels. That is, the mapped offshore marsh may be inundated shrubs and graminoid vegetation, or partially exposed patches of shore zone marsh.
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-297
Table 6.3.5-19: Shore Zone Wetland Composition of the Pre-Hydroelectric Development and Existing Environment Classified Large River Shorelines of the Upper Churchill Terrestrial Region for Overlapping Areas
Shore Zone Wetland Type
Pre-Hydroelectric Development Existing Environment
Length (km)
Percentage of Mapped Shoreline
Length (km)
Percentage of Mapped Shoreline
Narrow marsh 0 0 - - Riparian peatland 43 17 24 14
Mixture of riparian peatland and narrow marsh 1 0 - -
Mixture of riparian peatland and moderately-wide marsh
9 3 2 1
Peatland - - 114 66
Mixture of peatland and narrow marsh - - 1 1
Mixture of peatland and riparian peatland - - 0 0
Open water 200 79 30 17
Total 253 100 171 100 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
Table 6.3.5-20: Offshore Wetland Composition of the Pre-Hydroelectric Development and Existing Environment Classified Large River Shorelines of the Upper Churchill Terrestrial Region System for Overlapping Areas
Offshore Wetland Type
Pre-Hydroelectric Development Existing Environment
Length (km)
Percentage of Mapped Shoreline
Length (km)
Percentage of Mapped Shoreline
Occasional marsh - - 6 3 Narrow marsh 1 0 21 12
Moderately wide
- - 7 4
Wide marsh - - 3 2
Pondweed 18 7 - -
None 234 93 135 79
Total 253 100 171 100 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
Tadoule
Lake
LakeShethanei
Fox LakeCree Nation
York FactoryFirst Nation
War LakeFirst Nation
Ilford (NAC)
TataskweyakCree Nation
Southern IndianTerrestrial
Region
BradshawTerrestrial
RegionUpper Churchill
TerrestrialRegion
Southern IndianTerrestrial
Region
280
280
280
280280
280
280
280
KelseyG.S.
LongSpruce
G.S.KettleG.S.
KeeyaskG.S.
Lake
Namaypin
Lake
L
Tetroe
Odei
Hunter R
MuskegoLake
L
LakeBarnes
Roe Lake
BaldockLake
BreastPartridgeL
Lake
LakeAshley
Starrett
LakePennie
Lake
Pott
Lake
Noguy
Aiken
Lake
LakeLifebuoy
Lake
Legary
Paragon
Lake
WalfordLake
Lake
Wishart
Lake
Oldman
Currie
Lake
Wood
NorthernLake
LakeThorsteinson
Gauer
River
Lake
LakeJensen
Warnews
R
Meridian
LRock
Strong
Lake
LakeOrr
Odei
Lake
LPearson
Blank
R
LakeStone
Campbell
White
Lake
Lake
KiaskL
Handle
LakeWernham
HoodLake
Lake
Indian
LakeSmall
HibbertLake
KnifeheadLake
LakeLake
Blyth
North
Knife
Drift
L R
QuinnLake
River
LakeLovat
TraerLake
Beganili
AllanLake
Lake
PisewLake
EtawneyLake
Little
Naykow
River
Lake
Fidler
Lake
SetteeLake
ChristieL
LakePelletier
Clay
R River
AsseanLake
River
LakeHunting
River
Hunting
Lake
Lake
BissetCaldwell
LakeThomasL
Holmes
Lake
Churchill
Solmundsson
Lake
LakeKotchapaw
Buckland
KnifeSouth
Lake
North
Fabas
L
Lake
Thousin
LakeNichol
NaresLake
Condie
EinarsonLake
Lake
GylesLake
MinikwakunisLake
Beaver
LakeFreeman
River
R
Bieber
Assaikwatamo
Hale
Lake
Waskaiowaka
River
Sinclair
Aiken
Split
Fox
LakeCrying
L
Little
RecluseLake
R
LakeLakeEmbleton
L
Billard
Hogg
MountainRapids
TheFours
River
LakeComeau
Gersham
Creek
Matonabee
Skromeda
Knife
Creek
South
KnightLake
Mack
Braden
L
Lake
RapidsSwallow
Churchill
LimestoneLake
NelsonBirthdayRapids
War
River Kettle
RiverLake
LakeButnau
LakeJean
GullLake
Wasagamow
L
River
Lakes
Bradshaw
Rapids
ChurchillRiver
Lake CacheKilnabad Rapids
LakeWise
Herriot
Knife
DickensLake
TeepeeFalls
Langille
River
Creek
Nowell
River
Lake
LakeLofthouse
Heppell
Creek
BishopLake
MunkLRankine
Laforte
Crosswell
Bad
Lake
TurcotteDeer L
Deer
Whiting
MistakeL
L
Lake
Whitecap
Cygnet
Cygnet Little
LL
Limestone
Stephens
Hawes
Atkinson
Lake
L
KettleLake
Wilson
R
Lake
River
LMyre
Strobus LWeir
Lake
LongLake
L
LakeOwl
Fly
River
River
LandingHead
Ck
Red PlaceRapids
Running
Rapids
RiverCreek
HolcraftL
BayButton
LFarnworth
Warkworth
Alston
LimestoneRapids
River
Dog
Ck
Moose
Horn
Lost
Weir
Kettle
AnglingCreek
North
1.0
14-OCT-15
ECOSTEM Ltd.
Created By: snitowski - B Size Portrait BTB - MAR 2015 Scale: 1:900,000
19-NOV-15
File Location: Z:\Workspaces\RCEA\Habitat Regulated System\Shore Wetland Upper Churchill Region Post.mxd
Hudson Bay
Thompson
Winnipeg
Churchill
Regional Cumulative Effects Assessment
NAD 1983 UTM Zone 14N
0 10 20 Kilometers
0 8 16 Miles
DATA SOURCE:
DATE CREATED:
CREATED BY:
VERSION NO:
REVISION DATE:
QA/QC:
COORDINATE SYSTEM:
Legend InfrastructureGenerating Station (Existing)
HighwayRailTransmission Line (Existing)Transmission Line (UnderConstruction)
Manitoba Hydro; Government of Manitoba; Government of Canada;ECOSTEM Ltd. Shore Zone Wetland Type
Post-Hydroelectric Development Upper Churchill Terrestrial Region
RCEA Region of Interest Generating Station (UnderConstruction)
Terrestrial Region
Shore Wetland ClassPeatlandRiparian PeatlandShallow WaterUnknown
Map 6.3.5-13
BradshawTerrestrial
Region
Upper ChurchillTerrestrial
Region
Southern IndianTerrestrial
Region
MissiFalls
NorthKnifeLake
KnifeLake
South
Kelsey
YorkLanding
Nonsuch
Willbeach
Wivenhoe
Luke
RapidsKettle
Tidal
Digges
Bylot
M'Clintock
Kellett
Herchmer
Thibaudeau
Fox LakeCree Nation
York FactoryFirst Nation
War LakeFirst Nation
Ilford (NAC)
TataskweyakCree Nation
Kelsey G.S.
KettleG.S.
KeeyaskG.S.
280
280
280
280
280
280
280
Namaypin
TetroeMuskegoLake
L
LakeBarnes
Roe Lake
BaldockLake
BreastPartridgeL
Lake
LakeAshley
Starrett
LakePennie
LakeShethanei
Pott
Lake
Noguy
Aiken
Lake
LakeLifebuoy
Lake
Legary
Paragon
Lake
WalfordLake
Lake
Wishart
Lake
Oldman
Currie
Lake
Wood
NorthernLake
LakeThorsteinson
Gauer
River
Lake
LakeJensen
Warnews
R
Meridian
LRock
Strong LakeOrr
Odei
Lake
LPearson
Blank
R
LakeStone
Campbell
White
Lake
Lake
KiaskL
Handle
LakeWernham
HoodLake
Lake
Indian
LakeSmall
HibbertLake
KnifeheadLake
LakeLake
Blyth
North
Knife
Drift
L R
QuinnLake
River
Lake
LakeLovat
TraerLake
Beganili
AllanLake
Lake
PisewLake
EtawneyLake
Little
Naykow
River
Lake
Fidler
Lake
SetteeLake
ChristieL
LakePelletier
Clay
R
AsseanLake
River
LakeHunting
River
Hunting
Lake
Lake
BissetCaldwell
LakeThomasL
Holmes
Lake
Churchill
Solmundsson
Lake
LakeKotchapaw
Buckland
KnifeSouth
Lake
North
Fabas
L
Lake
Thousin
LakeNichol
NaresLake
Condie
EinarsonLake
Lake
GylesLake
MinikwakunisLake
Beaver
LakeFreeman
River
R
Bieber
Assaikwatamo
Hale
Lake
Waskaiowaka
River
Aiken
Split
Fox
LakeCrying
L
Little
RecluseLake
R
LakeLakeEmbleton
L
Billard
Hogg
MountainRapids
TheFours
River
LakeComeau
Gersham
Creek
Matonabee
Skromeda
Knife
Creek
South
KnightLake
Mack
Braden
L
Lake
RapidsSwallow
Churchill
LimestoneLake
Nelson BirthdayRapids
River Kettle
LakeButnau
LakeJean
GullLake
Wasagamow
L
River
Lakes
Bradshaw
Rapids
ChurchillRiver
Lake CacheKilnabad Rapids
LakeWise
Herriot
Knife
DickensLake
TeepeeFalls
Langille
River
Creek
Nowell
River
Lake
LakeLofthouse
Heppell
Creek
BishopLake
MunkLRankine
Laforte
Crosswell
Bad
Lake
TurcotteDeer L
Deer
Whiting
MistakeL
L
Lake
Whitecap
Cygnet
Cygnet Little
LL
Limestone
Stephens
AtkinsonL
KettleLake
Wilson
R
Lake
River
LMyre
Strobus LWeir
Lake
LongLake
L
LakeOwl
Fly
River
River
LandingHead
Ck
Red PlaceRapids
Running
Rapids
RiverCreek
HolcraftL
BayButton
LimestoneRapids
River
Dog
Ck
Moose
Horn
Lost
Weir
Kettle
Creek
North
Gillam
Churchill
1.0
17-JUN-15
ECOSTEM Ltd.
Created By: snitowski - B Size Portrait BTB - MAR 2015 Scale: 1:880,000
19-NOV-15
File Location: Z:\Workspaces\RCEA\Habitat Regulated System\Shore Debris Upper Churchill Region Post.mxd
Hudson Bay
Thompson
Winnipeg
Churchill
Regional Cumulative Effects Assessment
NAD 1983 UTM Zone 14N
0 10 20 Kilometers
0 8 16 Miles
DATA SOURCE:
DATE CREATED:
CREATED BY:
VERSION NO:
REVISION DATE:
QA/QC:
COORDINATE SYSTEM:
Manitoba Hydro; Government of Manitoba; Government of Canada;ECOSTEM Ltd. Shoreline Debris
Post-Hydroelectric Development Upper Churchill Terrestrial Region
LegendTerrestrial Region
RCEA Region of Interest
Shoreline Debris (Density, Coverage)NoneUnknown
InfrastructureGenerating Station (Existing)
Generating Station (Under Construction)Transmission Line (Existing)Transmission Line (Under Construction)Highway Rail
Map 6.3.5-14
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-300
6.3.5.1.3 Southern Indian Terrestrial Region
The development periods for the Southern Indian Terrestrial Region were as follows:
• the pre-development and pre-hydroelectric development periods both ended in 1971 with construction of a winter road to Missi Falls; and
• the hydroelectric development period was from 1971–2013.
BEFORE HYDROELECTRIC DEVELOPMENT
Terrestrial Habitat Composition
In 1971, prior to all human infrastructure development in this terrestrial region, land area (which equates to total historical native habitat), comprised approximately 79% of the 1,684,957 ha Upper Churchill Terrestrial Region. In 1971 infrastructure development began in the terrestrial region with a winter road to the future site of the Missi Falls CS.
Fine-textured lacustrine surface deposits dominated the terrestrial region (64% of land area), followed by till veneer (21%) and till blanket deposits (14%). By 1971, approximately 20% of the mineral deposits were covered by organic material that developed over millennia. Approximately 74% of the regional land area remained mineral soil (Table 6.3.5-1). Bedrock outcrop made up 6% of the regional land cover. Permafrost was widespread in organic soils.
Based on the small-scale SLC mapping, vegetation in the Southern Indian Terrestrial Region consisted of coniferous forest vegetation (43%), mixed forest vegetation (41%) and bog vegetation (16%).
The most abundant two coarse habitat types in the classified satellite imagery for the Southern Indian Terrestrial Region (Table 6.3.5-2) were intermediate age needleleaf treed vegetation on shallow to thin peatland (18%) and semi-open needleleaf treed with lichen-shrub understorey on shallow peatland to mineral soil (14%). The SLC mapping did not identify any shallow water table peatlands in the terrestrial region. The semi-open needleleaf treed with lichen-shrub understorey on shallow peatland to mineral cover type tended to be more abundant in the northern and western portions of the terrestrial region (Map 6.3.5-15).
Detailed terrestrial habitat mapping was available for approximately 55% of the total land area in the Southern Indian Terrestrial Region, covering the southern third of the terrestrial region, and the areas surrounding SIL and the Churchill River (Map 6.3.5-15). The smaller scale SLC mapping suggested that the ecosite composition of the detailed mapping area should be representative of the entire terrestrial region.
Detailed terrestrial habitat mapping for the Southern Indian Terrestrial Region was based on aerial photographs acquired in several different years, which represented different development periods. Mapping for the northern portion of the terrestrial region (45% of the mapped area) was from 1969 air photos, which represented pre-development conditions. Mapping for the remainder of the terrestrial region was from 1975 air photos, which represented initial post-development conditions prior to SIL
REGIONAL CUMULATIVE EFFECTS ASSESSMENT – PHASE II LAND – TERRESTRIAL HABITAT
DECEMBER 2015 6.3-301
reaching full supply level. Mapping for the area eventually flooded included the 1969 photo coverage area plus an area to the south represented by 1969 and 1971 aerial photographs acquired at a 1:32,000 scale.
Pre-development native habitat composition for the entire terrestrial region was estimated from the combined data sets. Since the human footprint, which is the amount of direct terrestrial habitat loss and alteration, in the 1975 mapping comprised only 1.2% of the regional land area, pre-development and existing environment habitat composition in the 1975 mapping area were virtually identical. While the mapping of the eventually flooded area for the entire terrestrial region and the 1969 detailed mapping indicated that there was a higher proportion of wet peatlands in the flooded areas than in the remainder of the terrestrial region, using the existing environment proportions for the 1975 flooded area would not affect the reported habitat composition percentages.
Pre-development land cover in the detailed terrestrial habitat mapping area of the Southern Indian Terrestrial Region (Map 6.3.5-15) was dominated by needleleaf treed vegetation on mineral soil or thin peatland (48%; predominantly black spruce on thin peatland, with jack pine treed on mineral), followed by needleleaf treed vegetation on other peatlands (46%; Table 6.3.5-8). Low vegetation on other peatlands and broadleaf treed on all ecosites made up most of the remaining area.
There was no permanent human infrastructure in the pre-hydroelectric development mapping for this terrestrial region.
Ecosystem Diversity
Ecosystem diversity results were primarily based on the habitat composition of the available detailed mapping area, which was considered representative of the terrestrial region as a whole.
Broad habitat types were not evenly distributed in the detailed mapping area of the Southern Indian Terrestrial Region. Three of the 21 native broad habitat types in the terrestrial region were estimated to comprise 71% of the total pre-development habitat area (Table 6.3.5-4). Four broad habitat types were regionally uncommon, and three were regionally common.
The detailed terrestrial habitat and flooded area mapping indicated that the Southern Indian Terrestrial Region included at least 18 priority habitat types (Table 6.3.5-9). Flooded area mapping, which used much broader categories than the detailed mapping, indicated that the flooded areas outside of the 1969 mapping area had a somewhat higher proportion of tall shrub and/or low vegetation on riparian and wet peatlands. Consequently, the abundance of these types might be somewhat underestimated, but the difference in area would not be enough to change the priority status of these habitat types.
Priority habitat was not evenly distributed throughout the detailed mapping area. Almost all of the jack pine and broadleaf habitat was located in the southern third of the terrestrial region (Map 6.3.5-15).
Lake
Granville
Highrock
Pikwitonei(NAC)
NisichawayasihkCree Nation
Nelson House (NAC)
RCEAArea 3
Upper ChurchillTerrestrial
Region
RCEAArea 3
O-Pipon-Na-PiwinCree Nation
South Indian Lake
NisichawayasihkCree NationNelson House (NAC)
Upper ChurchillTerrestrial
Region
Southern IndianTerrestrial
Region
391
493
391
493
280
391391
391
280
493
391
391
L
LakeKustra
LakeJordan
LakeUnagimau
MelvinL
Barrington
Barrington
Lake
LakeAdam
LeafRapids
Eden
Lake
CostelloLake
Suwannee
Lake
Nelson
Lake
HallLake
River
LakeGoodwin
Rat
Pemichigamau
Karsakuwigamak
River
Lake
River
Lake
MacBrideOpachuanau
McfaddenFraser
GrandmotherLake
MaxwellLake
LakeMorand
Big
Lake
Sand
Denison
LakeHurst
Lake
McphersonLake
Enatik
Lake
L
Lake
RustyLake
Lake
LRuttan
Lake
Rat
Lake
LakeWapisoLake
Notigi
OsikL
R
Misinagu
LakeLake
Mynarski
Rat
IssettL
Is
Lemay
LakeMulcahy
MacKerracherMuskwesi
Lake
LSedgwick
LakeWolf
LakeSamson
CommemorationLake
SouthTrout
SandbergL
Lake
Moss
River
Nutter SouthernLake
NumakoosL
Pine
Indian
Lake
Lake
SouthBay
Bay
River
KinwawLake
Lakes
L
Macheewin
Fold
Leftrook
Lake
LRidgeLivingston
Lake
Swan
Cousins
Uhlman
Lake
BaySandhill
LongPoint
IsLoon
L
SandL
Little
OtterL
Lake
LoonL
ChipewyanLake
BenoitGimby Lake
Lake
Seal
LakeCederland
Namaypin
TorranceLake
LakeChapman
Gauer
Lake
BroughtonL
LHarding Tetroe
OdeiLNile
Hunter RL
MuskegoLake
L
LakeBarnes
Roe Lake
Baldock
Lake
BreastPartridge
L
Lake
LakeAshley
WalfordLake
Lake
Wishart
Lake
Oldman
Currie
Lake
WoodLake
Lake
Thorsteinson
Gauer
River
Lake
LakeJensen
Warnews
R
LRock
Strong
Moak
Lake
ApussigamasiLake
Lake
Burntwood
LakeOrr
Lake
LPearson
Blank
R
LakeStone
Campbell
White
Lake
Lake
KiaskL
Handle
LakeWernham
HoodLake
Lake
Indian
LakeSmall
HibbertLake
KnifeheadLake
LakeLake
BlythKnife
PisewLake
EtawneyLake
Naykow
River
Lake
Fidler
Lake
Pelletier
Clay
R
LakeBrannigan
GrassNatawahunan
LakeBegg
1.0
08-OCT-15
ECOSTEM Ltd.
Created By: snitowski - B Size Portrait BTB - MAR 2015 Scale: 1:758,000
01-DEC-15
File Location: Z:\Workspaces\RCEA\Habitat OffSystem\Coarse Habitat Southern Indian Region.mxd
Hudson Bay
Thompson
Winnipeg
Churchill
Regional Cumulative Effects Assessment
NAD 1983 UTM Zone 14N 0 8.5 17 Kilometers
0 7 14 Miles
DATA SOURCE:
DATE CREATED:
CREATED BY:
VERSION NO:
REVISION DATE:
QA/QC:
COORDINATE SYSTEM:
Manitoba Hydro; Government of Manitoba; Government of Canada;ECOSTEM Ltd.; Habitat based on 2005 MTLCC 250m Map. Coarse Habitat Pre and
Post-Hydroelectric DevelopmentSouthern Indian Terrestrial Region
LegendRCEA Region of Interest
Coarse Habitat from Classified Satellite ImageryBroadleaf Treed MixedwoodOpen Needleleaf Treed on Shallow Peatland to Mineral with Lichen-bedrock UnderstoreyOpen Needleleaf Treed on Shallow Peatland to Mineral with Shrub UnderstoreyOpen Needleleaf Treed on Shallow to Thin Peatland with Lichen-shrub-herb UnderstoreyOpen Needleleaf Treed on Shallow to Thin Peatland with Shrub-moss UnderstoreyOpen Needleleaf Treed on Shallow to Wet PeatlandOpen to Semi-closed Needleleaf Treed on Shallow Peatland to MineralOpen to Semi-closed Needleleaf Treed on Shallow to Thin PeatlandSemi-open Needleleaf Treed on Shallow Peatland to Mineral with Lichen-shrub UnderstoreySemi-open Needleleaf Treed on Shallow Peatland to Mineral with Moss-shrub UnderstoreySparse Needleleaf Treed on Shallow Peatland to Mineral with Herb-shrub UnderstoreyClosed Needleleaf Treed on Shallow Peatland to MineralClosed Needleleaf Treed on Shallow to Thin or Wet PeatlandClosed, Young Needleleaf Treed on Shallow to Thin PeatlandJack Pine Treed on Mineral or Thin PeatlandNeedleleaf Treed on Mineral to Shallow PeatlandNeedleleaf Treed on Mineral to Shallow Peatland with Herb-shrub-lichen-bare UnderstoreyNeedleleaf Treed on Mineral to Shallow Peatland with Shrub-herb-lichen-bare UnderstoreyNeedleleaf Treed on Shallow to Thin Peatland
Needleleaf Treed on Shallow to Thin Peatland with Herb-shrub UnderstoreyNeedleleaf Treed on Shallow to Thin Peatland with Intermediate AgePolar Grassland, Herb-shrubMix of Water and Black Spruce Treed on Shallow to Thin PeatlandMix of Water, Marsh and Black Spruce Treed on Thin Peatland
Young Regengerating, Needleleaf Treed on Shallow to Thin or Wet Peatland
WaterInfrastructure
Highway
Marsh with Substantial Proportions of Water and Black Spruce Treed onThin Peatland
Young Regengerating, Semi-open Needleleaf Treed on Shallow Peatland toMineral
Terrestrial Region
Map 6.3.5-15
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Wetland Function
Wetlands covered 76% of the available detailed mapping area in this terrestrial region (this total does not include shallow open water since water depths were not available), with peatlands accounting for this entire total (Table 6.3.5-10). Shallow and thin peatlands were the most abundant wetland types, followed by wet deep peatlands and riparian peatlands.
The highest quality mapped wetlands in this terrestrial region were riparian peatlands followed by wet deep peatlands (Table 6.3.5-10). The remaining peatland types had much lower wetland quality ratings than the other wetland types. It appears that the standards used by the source forest inventory data for this terrestrial region did not include capture marsh.
Shore zone wetlands, not including the pre-hydroelectric on-system wetlands addressed in the Shoreline Ecosystems section below, comprised 0.2% of the total mapped wetland area. These consisted entirely of riparian peatland.
Shoreline Ecosystems
Shoreline ecosystems in the Paint Terrestrial Region were virtually unaffected by human infrastructure development prior to the CRD. Based on estimates from 1:50,000 NTS data (see Section 6.3.1.5.5 for the limitations of these data), the pre-hydroelectric development Southern Indian Terrestrial Region included approximately 353,236 ha of surface water and 17,988 km of shorelines that provided potential shore zone and offshore wetland habitat. Based on a combination of available terrestrial habitat mapping outside of human-affected areas and pre-development habitat mapping in human footprints, vegetated shoreline wetlands and riparian peatlands comprised approximately 0.1% of total terrestrial habitat area in the terrestrial region. The vegetated shoreline wetland percentage would have fluctuated from year to year in these dynamic ecosystems.
Waterbodies that would eventually be affected by the CRD contributed to approximately 54% (191,724 ha) of the surface water area and 26% (4,653 km) of the shoreline length. A large portion of this shoreline was in the Churchill River mainstem and SIL) (73%; Table 6.3.5-21). Riverine lakes provided 4% of shoreline length, and smaller tributaries flowing into the main river provided 2% of the shoreline. Unconnected lakes that would become part of the regulated system after hydroelectric development made up 3%. The rest of the shoreline was in riverine bays and back bays of the larger lakes (18% combined). In terms of mainland versus islands, islands accounted for 43% of shoreline length.
Data were available to classify approximately 98% (4,536 km) of the pre-development large river system shore zone habitat in the terrestrial region, from historical aerial photographs acquired on various dates between August 1969 and October 1971. Clay bank materials were predominant along the mapped shoreline (90% of shoreline length; Map 6.3.5-16), either as a pure type (13%) or overlying bedrock (77%; Table 6.3.5-22; bank material mapped for 97% of the shoreline). The remainder of the banks were sand (6%), gravel (3%) and bedrock (2%). Peat and human disturbed banks each made up less than 1% of the shoreline. Bank failures large enough to map were not apparent in the stereophotos.
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Table 6.3.5-21: Waterbody Type along the Pre-Hydroelectric Development and Existing Environment Shorelines in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone
Waterbody Type Pre-Hydroelectric Development Existing Environment
Length (km) Percentage of Length Length (km) Percentage of
Length
Lake 41 1 154 3 Large lake 3,113 67 3,089 65
River 130 3 75 2
Small river 96 2 49 1
River widening 116 2 - -
Riverine lake 206 4 324 7
Riverine bay 370 8 442 9
Back bay 454 10 593 12
Off-system waterbody 121 3 29 1
Total 4,647 100 4,755 100 Notes: Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
Table 6.3.5-22: Bank Material Composition of the Pre-Hydroelectric Development Classified Shorelines in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone
Bank Material Length (km) Percentage of Mapped Shoreline
Bedrock 72 2 Clay on low bedrock 2,955 65
Clay on bedrock 546 12
Clay 572 13
Sand 220 5
Sand on clay 33 1
Mixture of sand and gravel 2 0
Gravel 130 3
Peat 6 0
Human 1 0
Total 4,536 100 Total unmapped shoreline 443 Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding.
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Low banks were the most common bank height (71% of shoreline length), followed by moderate height (17%), low to moderate (6%), high bank (3%) and moderate to high (1%; Table 6.3B-4; bank height mapped for 98% of the shoreline). Low banks were not strongly associated with a particular bank material. Moderate to high banks were more strongly associated with clay on bedrock bank materials.
Where beaches could be classified from the historical aerial photographs, they were predominantly bedrock (60% of shoreline length) and clay (27%; beach material mapped for 89% of the shoreline). Sand (8%) and gravel (4%) beaches were also present (Table 6.3B-5).
Shallow open water was the predominant shore zone wetland type (79%) along the classified shoreline (Table 6.3.5-23; shore zone wetlands mapped for 91% of the shoreline). Marsh occurring in the various density and width classes was present along 9% of the mapped shoreline. Riparian peatlands accounted for 7% of the shoreline, while mixtures of riparian peatland and marsh (4%) and mixtures of peatland and marsh (< 1%) occurred along the remainder of the shoreline.
Marshes were found in the large lake and back bay waterbody types throughout the mapped waterbodies (Map 6.3.5-17; as described in Section 6.3.1.5, waterbody limits used to subdivide the river system may differ from those found in the Physical Environment [IV] and Water [V] Parts; see Section 6.3.1.5 for definitions of the shore zone wetland types). Riparian peatlands were most abundant in the large lake and riverine bay waterbody types.
Offshore emergent or floating-leaved vegetation occurred along 9% of the mapped shoreline, consisting of marsh in various width and density classes or pondweed (Table 6.3.5-24; offshore wetlands mapped for 90% of the shoreline). Offshore pondweed was present along approximately 8% of the shore zone. Offshore emergent vegetation was most frequent in the main lake, while pondweed occurred in the main lake and off-system waterbodies.
None of the classified shoreline had mappable shoreline debris (Table 6.3.5-25 shoreline debris mapped for 34% of the shoreline).
A mappable tall shrub band occurred along 7% of the classified shoreline, with the narrowest class being most common. Wide tall shrub bands mainly occurred in SIL Area 5 (Table 6.3B-8; tall shrub band mapped for 97% of the shoreline).
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Table 6.3.5-23: Shore Zone Wetland Composition of the Pre-Hydroelectric Development Classified Shorelines in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone
Shore Zone Wetland Type Length (km) Percentage of Mapped Shoreline
Occasional marsh 158 4
Narrow marsh 104 2
Moderately wide marsh 98 2
Wide marsh 33 1
Riparian peatland 297 7
Mixture of riparian peatland and narrow marsh 83 2
Mixture of riparian peatland and moderately-wide marsh 54 1
Mixture of riparian peatland and wide marsh 21 0
Mixture of peatland and narrow marsh 2 0
Mixture of peatland and occasional marsh 3 0
Mixture of open water and unknown 19 0
Open water 3,333 79
Mixture of unknown and open water 2 0
Total 4,208 100
Total unmapped shoreline 443
Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding.
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Table 6.3.5-24: Offshore Wetland Composition of the Pre-Hydroelectric Development Classified Shorelines in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone
Offshore Wetland Type Length (km) Percentage of Mapped Shoreline
Narrow marsh 19 0 Moderately wide marsh 28 1 Wide marsh 10 0 Mixture of narrow marsh and pondweed 2 0 Pondweed 330 8 Riparian peatland 1 0 None 3,797 90 Mixture of none and unknown 19 0 Total 4,206 100 Total unmapped shoreline 445 Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding.
Table 6.3.5-25: Shoreline Debris Accumulation and Distribution along the Pre-Hydroelectric Development and Existing Environment Classified Shorelines of the Southern Indian Terrestrial Region for Overlapping Areas
Shoreline debris accumulation
Shore segment coverage
Pre-Hydroelectric Development
Existing Environment
Length (km)
Percentage of Length
Length (km)
Percentage of Length
None - 1,560 99 988 62 Mixture of none and unknown 17 1 - -
Light Moderate - - 86 5
Continuous - - 39 2
Moderate Low - - 126 8
Moderate - - 133 8
Continuous - - 77 5
Heavy Low - - 1 0
Moderate - - 57 4
Continuous - - 75 5
Total 1,577 100 1,581 100 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.
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AFTER HYDROELECTRIC DEVELOPMENT
Terrestrial Habitat Composition
Infrastructure development during the hydroelectric development period directly removed approximately 13,256 ha, or 1%, of native terrestrial habitat in the Southern Indian Terrestrial Region (Intactness, Section 6.2.5.1.1). Dewatering resulting from the CRD exposed an approximate additional 2,391 ha of land area. The indirect effects of all human infrastructure development, flooding and dewatering were estimated to have altered an additional 23,923 ha, or 1.8%, of terrestrial habitat as of 2013 (see Section 6.3.1.5.1. for discussion of the potential indirect effects).
Hydroelectric development contributed 97% of the direct habitat loss (dewatered area not considered as a terrestrial habitat loss) and 39% of the indirect habitat effects (including indirect effects of dewatering) in this terrestrial region. Flooding was responsible for 82% of the direct changes as of 2013.
The terrestrial habitat types most affected by all forms of infrastructure development in this terrestrial region included needleleaf treed vegetation on other peatlands and needleleaf treed vegetation on mineral or thin peatland. Based on the 1:32,000 land cover mapping of flooded areas, the land cover types most affected by flooding in the Southern Indian Terrestrial Region included needleleaf treed vegetation on mineral soil or thin peatland (62%), followed by needleleaf vegetation on shallow peatland (10%; Table 6.3.5-26). Tall shrub and low vegetation on riparian peatlands made up an additional 18% of the flooded areas combined. This composition and that from the 1969 detailed mapping that partially covered the flooded area (Table 6.3.5-27) were similar. The detailed mapping had a higher proportion of needleleaf treed on shallow peatlands in the flooded areas (37%) than the flooded area mapping. Detailed mapping also had a higher proportion of low vegetation on wet peatland (21%), but an examination of the mapped areas indicated that most of this area was equivalent to the tall shrub and low vegetation on riparian peatlands from the coarse mapping.
Dewatered area mapping based on 1982 air photos indicated that the composition of the land eight years after being exposed by dewatering was predominantly low vegetation on mineral soil (includes exposed mineral terraces; Table 6.3.5-16). Most of the remaining dewatered area was a barren, non-vegetated mineral. Based on the mapped land cover composition within 100 m of the dewatered zone in the terrestrial region, the most common land cover type indirectly affected by dewatering included needleleaf treed vegetation on mineral soil or thin peatland, followed by needleleaf mixedwood vegetation on mineral soil or thin peat (Table 6.3.5-17). Lower-lying shallow and deep peatlands would be more susceptible to indirect effects, but these made up only 2% of the inland cover in the terrestrial region.
Medium-term indirect effects from dewatering on this inland habitat were expected to be limited because it was already an upland vegetation type. Over the longer term, the edge habitat may disappear or shift to the new shoreline location as treed vegetation develops in the dewatered area. The direct and indirect effects of winter roads on terrestrial habitat were less than from other human footprint types since the associated effects were generally limited to clearing taller vegetation, and were primarily used in the winter, whereas other footprint types typically included soil excavation and a permanent infrastructure cover.
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Table 6.3.5-26: Pre-Development Land Cover Composition of Flooded Areas in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone 1
Land Cover Type Percentage of Flooded Land
Percentage of Regional Land Area
Barren on all ecosites 0 0.0
Needleleaf treed on outcrop 0 0.0
Broadleaf treed on all ecosites 1 0.0
Needleleaf treed on mineral or thin peatland 62 0.7
Needleleaf treed on other peatlands 18 0.2
Tall shrub on other peatlands 0 0.0
Low vegetation on other peatlands 0 0.0
Shrub/ low vegetation on riparian peatland 18 0.2
Shore zone 1 0.0
Total Pre-Development Land Area (ha) 12,844 1,321,225 Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding. 1. From 1:32,000 coarse mapping.
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Table 6.3.5-27: Pre-Development Land Cover and Coarse Habitat Composition of Flooded Areas in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone 1
Land Cover Type Coarse Habitat Type Percentage of Flooded Land
Percentage of Regional Land
Area
Broadleaf treed on all ecosites
Broadleaf mixedwood on all ecosites 1 0.0
Broadleaf treed on all ecosites 1 0.0
Needleleaf treed on mineral or thin peatland
Black spruce mixedwood on mineral or thin peatland 1 0.0
Black spruce treed on mineral soil 0 0.0
Black spruce treed on thin peatland 33 0.3
Jack pine treed on mineral or thin peatland 0 0.0
White spruce treed on mineral 0 0.0
Needleleaf treed on other peatlands
Black spruce treed on shallow peatland 37 0.3
Low vegetation on other peatlands Low vegetation on wet peatland 21 0.2
Shrub/ low vegetation on riparian peatland Tall shrub on riparian peatland 2 0.0
Shore zone and small islands 5 0.0
Total Pre-Development Land Area (ha) 11,342 1,321,225 Notes: Values of “0” indicate a number that rounds to zero. Subtotals may not appear to reflect sum due to rounding. 1. From available detailed terrestrial habitat mapping.
Ecosystem Diversity
The following material only includes the broad habitat types present in the detailed terrestrial habitat mapping. While additional types may be found elsewhere in the Southern Indian Terrestrial Region, it is unlikely they were affected by hydroelectric development since the detailed mapping includes virtually the entire hydroelectric development footprint.
Flooded area mapping indicated that the 1.2% of native terrestrial habitat that was lost by 2013 did not eliminate any broad habitat types in this terrestrial region, and did not substantially change the proportion of any broad habitat types. The proportion of low vegetation on wet peatland in flooded areas, which was disproportionately affected by flooding, was approximately 0.2% of the pre-development habitat area and its loss did not change that habitat type’s status as an uncommon type. It appeared that the total number of common, uncommon and rare habitat types within the detailed mapping area as of 2013 was the same as in 1971.
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As indicated in the terrestrial habitat section, winter roads, which contributed most of the remaining habitat loss, typically affected all types of ecosites because they were not preferentially located on upland terrain. The other types of footprints that tend to preferentially affect mineral and upland habitats (e.g., borrow areas) were too small to noticeably alter the proportions of priority habitat at the regional level.
With the exception of a small amount of development around the community of South Indian Lake at the southern border of the terrestrial region (O-Pipon-Na-Piwin Cree Nation, or South Indian Lake itself is located in the Western Boreal Shield Ecozone), all of the ecosystem diversity effects in the Southern Indian Terrestrial Region were related to hydroelectric development.
Wetland Function
Wetlands comprised approximately 89% of the habitat affected by flooding in the terrestrial region. Shallow peatlands were the wetland types most affected in terms of total area (39%), followed by thin peatland (33%; Table 6.3.5-28). Wet deep peatland and riparian peatlands made up the remaining wetland area lost. With the exception of riparian and wet deep peatlands, the wetland forms corresponding with the preceding ecosite types (Table 6.3.5-10) had relatively low wetland quality ratings.
As indicated in the previous sections, the amount of wetlands lost relative to the regional area was not enough to substantially affect wetland composition. Large river shoreline wetlands that may have been affected are addressed in the Shoreline Ecosystems section below.
Table 6.3.5-28: Wetland Coarse Ecosite Types in Flooded Areas Pre-Hydroelectric Development in the Southern Indian Terrestrial Region of the Taiga Shield Ecozone
Coarse Ecosite Type Percentage of Wetland Area
Riparian Peatland 7
Wet deep peatland 21
Shallow peatland 39
Thin peatland 33
All 100
All Flooded Wetlands (ha) 912 Notes: Subtotals may not appear to reflect sum due to rounding.
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Shoreline Ecosystems
Flooding and dewatering resulting from the CRD altered shorelines along the shores of SIL and the Churchill River in the Southern Indian Terrestrial Region. The total regional surface water area increased from approximately 353,236 ha to 363,732 ha, and increased regulated system shoreline length to 4,757 km from 4,653 km (see Sections 6.3.1.5.5 for the limitations of these data).
Dewatered area mapping from 1982 photography indicated that low vegetation and tall shrubs were beginning to establish on the exposed mineral terraces and riverbeds along the Churchill River.
For the RCEA, one or more shore zone attributes were mapped for approximately 33% of the existing environment shoreline (the southwestern third of the lake) from high resolution satellite imagery acquired in July 2006. Water levels in this remote sensing were close to immediately prior median levels in the reaches with daily water level data. The habitat inland of the available classified shoreline had a higher proportion of mineral habitat than the rest of the lake (see Map 6.3.5-15). Therefore, the classified shoreline results may not be representative of the remainder of the lake.
Reaches with both pre-hydroelectric development and existing environment shore zone mapping for at least one attribute comprised 35% of shoreline length. All of the following results that compare existing environment with pre-hydroelectric development values are based on the areas that have both pre-hydroelectric development and existing environment shore zone mapping, the spatial extent for which varies with attribute (e.g., bank material available for 32% of shoreline, shore zone wetland for 33%).
Hydroelectric development effects on waterbodies included increasing total surface water area by approximately 10,421 ha, or 5%, and total shoreline length from 4,653 km to 4,757 km, or 2%.
The total amount of clay bank (either pure or overlaying bedrock) remained proportionally the same, with an overall decrease of about 87 km of shoreline length (Table 6.2.3-29; Map 6.2.5-18; bank material mapped for 32% of the shoreline). Clay on low bedrock decreased by about 301 km, or 16% of shoreline length, and pure clay increased by about 311 km, or 21%. Flooding raised water levels above the bedrock base along much of the shoreline that was clay on low bedrock prior to hydroelectric development as well as a substantial percentage of what was clay on bedrock shoreline. Sand banks decreased to less than 1% of the shoreline and gravel banks disappeared, while peat banks increased from nothing to about 50 km in total (3% of shoreline length), as the new waterline often established on peatlands inland of the pre-development river banks.
High and moderate banks virtually disappeared in the existing environment mapping for this re region (Table 6.3B-9), but shoreline with low, or mixtures of low to moderate banks increased substantially in length (1,010 to 1400 km in total). Banks with no height also increased in length (1 to 44 km) in the terrestrial region.
Bank failures were mapped along just over approximately 0.6% of the shoreline. These occurred in four scattered locations along the mapped shoreline, associated with low to moderate height clay banks with moderate to high slope.
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Table 6.3.5-29: Bank Material Composition of the Pre-Hydroelectric Development and Existing Environment Classified Shorelines of the Southern Indian Terrestrial Region System for Overlapping Areas
Bank Material
Pre-Hydroelectric Development Existing Environment
Length (km)
Percentage of Mapped Shoreline
Length (km)
Percentage of Mapped Shoreline
Bedrock 37 2 0 0
Clay on low bedrock 1,147 71 845 55
Mixture of clay on low bedrock and clay - - 62 4
Clay on bedrock 243 15 26 2
Clay 169 10 480 31
Mixture of clay and clay on low bedrock - - 59 4
Mixture of clay and peat - - 7 0
Sand 11 1 6 0
Sand on clay 12 1 - -
Mixture of sand and gravel 2 0 - -
Gravel 1 0 - -
Peat - - 50 3
Mixture of peat and clay - - 3 0
Human - - 2 0
Total 1,621 1,540 Notes: Values of “0” indicate a number that rounds to zero. Values of “-” indicate an absence. Subtotals may not appear to reflect sum due to rounding.