STREAM POWER MAPPING OF GLACIALLY CONDITIONEDRIVER CATCHMENTS IN SOUTHERN ONTARIO

INTRODUCTION AND EXECUTIVE SUMMARY

Roger T.J. Phillips and Joseph R. Desloges

Department of Geography, University of Toronto, 100 St. George Street, Toronto, ON M5S 3G3

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roger.phillips@utoronto.ca

Lawrence Ave.

1) STUDY AREA AND STREAM POWER0 50km

N

2 5

2) DISCHARGE AND WIDTH REGIME MODELS

Source Region Discharge, Q � � R2

n

This study Southern Ontario 2 Year 0.2483 0.9095 0.86 210

This study - South Georgian Bay (I) 2 Year 0.2042 0.8634 0.84 25

This study - Toronto and Region (II) 2 Year 0.2830 0.8633 0.86 32

This study - Niagara Peninsula (III) 2 Year 0.1560 0.9454 0.82 24

This study - Grand River (IV) 2 Year 0.2439 0.9367 0.92 38

This study - Lake Erie North Shore (V) 2 Year 0.0944 1.0461 0.79 22

This study - Thames St. Clair (VI) 2 Year 0.4002 0.8758 0.93 34

This study - South Lake Huron (VII) 2 Year 0.4028 0.9013 0.97 22

This study - Saugeen River (VIII) 2 Year 0.1515 1.0023 0.87 23

Gingras et al. (1994) Ontario and Quebec 2 Year 0.6397 0.734 0.70 183

Gingras et al. (1994) - Lake Ontario, Erie, St. Clair (Region 7) 2 Year 0.2393 0.946 0.86 49

Gingras et al. (1994) - Lake Huron (Region 8) 2 Year 0.2438 0.883 0.88 13

Annable (1996) Southern Ontario (All Rosgen Stream Types) Bankfull 0.52 0.74 0.64 47

Annable (2011) Southern Ontario (Urban and Rural) Bankfull 0.6 0.73 - 49

Mulvihill et al. (2009) New York State Bankfull 1.067 0.810 0.89 82

Mulvihill et al. (2009) - Lake Ontario (New York State) Bankfull 0.730 0.765 0.94 10

Mulvihill et al. (2009) - Lake Erie (New York State) Bankfull 0.911 0.842 0.90 14

Richol et al. (2009) Southern Michigan State Bankfull 0.073 0.950 0.60 28

Sherwood et al. (2005) Ohio – Lake Erie Bankfull 1.951 0.637 0.82 37

Source Region Width, W a b R2

n

This study Southern Ontario (All Data) Bankfull 1.1595 0.5082 0.87 542

This study Southern Ontario (Censored) Bankfull 1.2012 0.4992 0.88 493

This study - Nottawasaga River (1) Bankfull 1.1142 0.4589 0.79 69

This study - Toronto and Region (2, 3) Bankfull 1.8464 0.4113 0.88 47

This study - Welland River, Niagara (4) Bankfull 1.2110 0.5797 0.81 35

This study - Grand River (5) Bankfull 0.8924 0.5584 0.93 54

This study - Lake Erie North Shore (6) Bankfull 2.0514 0.3984 0.78 48

This study - Thames St. Clair River (7, 8) Bankfull 1.4496 0.4749 0.93 25

This study - Ausable, Bayfield Rivers (9) Bankfull 0.9910 0.5193 0.89 129

This study - Maitland River (10) Bankfull 0.7316 0.5941 0.94 46

This study - Saugeen River (11) Bankfull 1.3173 0.4904 0.89 110

Annable (1996) Southern Ontario (All Rosgen Stream Types) Bankfull 3.71 0.49 0.61 47

Mulvihill et al. (2009) New York State Bankfull 4.256 0.401 0.84 281

Mulvihill et al. (2009) - Lake Ontario (New York State) Bankfull 2.647 0.458 0.89 33

Mulvihill et al. (2009) - Lake Erie (New York State) Bankfull 4.220 0.419 0.79 50

Richol et al. (2009) Southern Michigan State Bankfull 2.025 0.440 0.69 28

Sherwood et al. (2005) Ohio – Lake Erie Bankfull 4.632 0.356 - 45

Faustini et al. (2009) Conterminous USA Bankfull 2.81 0.24 0.42 1558

Faustini et al. (2009) - Eastern Highlands, USA Bankfull 2.68 0.38 0.75 275

Faustini et al. (2009) - Great Lakes, USA Bankfull 2.45 0.33 0.62 53

Faustini et al. (2009) - Northern Appalachians, USA Bankfull 2.55 0.39 0.72 87

Faustini et al. (2009) - Upper Midwest, USA Bankfull 1.74 0.39 0.68 70

Table 1: Discharge regime models Table 2: Channel width regime models

3) DEM Channel Slope Extraction

Figure 3: Statistical regression models for (left) 2 year flood discharge (Q )

and (right) channel width (w ) versus drainage area (A ). Short dash lines are

95% confidence intervals and long dash lines are 95% prediction intervals.Censored red data points in width model were excluded as outliers in a second testbased on effects of vegetation in headwaters, urbanization, and lake backwater.

2

bf d

Figure 1: Specific stream power mapping for select major rivers and tributaries in southern Ontario, in the context of glacial landformmapping by Chapman and Putnam (1984, 2007).

Continuous mapping of discharge and channel width along each river profile wasderived from statistical regime models predicted by drainage area (A - calculated

from the provincial 10 m digital elevation model). Discharge (Q) models are basedon flood frequency analysis of the annual maximum mean daily discharges for 210stream flow gauges in southern Ontario (WSC, 2011). Channel width (w) models arebased on rapid surveys of bankfull width from ~500 sites. Locations of stream flowgauges and rapid width surveys are presented in . Statistical regression oflog-transformed data were used to produce power-law regime models of the form:

where statistical results for southern Ontario yield 0.25 and 0.91 for flood

discharge frequencies of a 2 year return period (Q ); and a 1.2 and b 0.5 for

bankfull channel width (w ). Statistical regression models and data, including 95%

confidence and prediction intervals, are plotted in . The detailed sub-regionresults for the model coefficients and exponents are presented in .

d

2

bf

Figure 2

Figure 3

Tables 1 and 2

Q = A (Eq. 2) w = aA (Eq. 3)� d d

� b

� �≈ ≈

≈ ≈

Peninsular southern Ontario is surrounded by the Great Lakes of Huron, Erie, andOntario, which are perched within a low-relief topography of Paleozoic sedimentarybedrock and Pleistocene glacial sediments. River systems in the study area drain tobase-levels of these three lower Great Lakes and have relatively small drainageareas of less than 10 km .

The purpose of this study was to map the spatial properties of stream power insouthern Ontario, for eleven (11) major watersheds ( ), within thecontext of glacial landforms and sediments (Chapman and Putnam, 1984, 2007). Asthese fluvial systems are carved into the complex architecture of glacial overburdenand have evolved over relatively short geologic timescales of about ten thousandyears, it is expected that the longitudinal profiles and boundary materials may still bestrongly conditioned by the glacial landscape.

Specific stream power ( ), or power per unit bed area (units of Watts per m ), is ameasure of the potential energy available in fluvial systems to perform geomorphicwork, namely sediment transport (Bagnold, 1966; Parker 2011). In practicalterms, mapping the spatial distribution of specific stream power only requires modelsof gross channel properties, such as channel slope (s) and width (w), as well asestimates of discharge (Q) conveyed through the drainage network:

where is the specific weight of water (9792.3 kg m m s at 20°C).

4 2

2

-3 -2

Figures 1 and 2

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� �= Q s w (Eq. 1)-1

No

Yes

DEM Processing - ArcGISHydrology Spatial Analysis Tools- Flow Direction & Accumulation (D8 Model)- Export stream profile data as 3D point file

2.5 m Vertical Slice

XWindow

Longitudinal Multi-PassMoving Window Averaging

X = 1 > 1.5 > 2 kmwindow

Assess ProfileSlope Variations

- Real Variations?

- Data artifacts?

- ImposedVariations?e.g., dams

Accept Profile?Yes or No?X = 2 > > 5 kmwindow

Expand Moving Window in0.5 km Increments

Calculate potential specific stream power ( )from slope (s), discharge (Q), and

width (w) models

= Q s w

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Import 3D stream profile data into GIS with

attributes of slope (s) and stream power ( )< Map Specific Stream Power >

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Figure 4: Flowchart of GIS andprofile processing for mapping ofspecific stream power.

Channel slope (s) was evaluated based onlongitudinal profiles derived from Ontario'sprovincial 10 m Digital Elevation Model (DEM)Version 2.0.0 (OMNR, 2008). Longitudinalprofiles of selected major river drainages insouthern Ontario were extracted as 3D pointsfrom the DEM using GIS, and channel gradientwas subsequently generalized as outlined in

. The scaling of the verticalslice was based on the reported absolutevertical accuracy of the DEM (2.5 m), and themoving window average was intended torepresent reach scale patterns in channelslope (1 - 2 km). The generalized channelslopes were used to calculate and map specificstream power as presented in .

Figures 4 and 5

Figure 1

Figure 5: Example profile for theAusable River.

Profile

Generalized Channel Slope

Vertical Slice DEM Gradient

Raw DEM Gradient

4) STUDY RESULTS AND CONCLUSIONS

REFERENCES AND ACKNOWLEDGEMENTS

Figure 6: A) B)

Eq. 4 C)

Slope-area analysis; Glacial landform classifications (Chapman and Putnam, 1984) and specific stream power curves; Bedmaterial grain size classifications compared to Hack (1957) ; and Channel planform classifications compared to threshold slope for

anabranching (s*, Eq. 5) with increasing bank strengths ( ’) based on dimensionless discharge (Q*) versus channel slope (Eaton 2010).� et al.

A B C

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VIII

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11

Lake

Huron

Lake

Erie

Lake

Ontario

Georgian

Bay

Legend

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0 50km

Stream Flow Gauges

Rapid Width Surveys

Figure 2: Study area map for southern Ontario showing select major riverdrainages (1 - 11) and sub-regions for discharge regime models ( ).I - VIII

Thanks to NSERC for financial support through a PhD CGS Scholarship to R.T.J. Phillips. Generous academic and financial support byco-author (Joe Desloges) has also been vital to this PhD thesis research. Honourable mention to many field assistants over period of2010-2011, namely Stephanie Mah, Joyce Arabian, Beata Opalinska, James Thayer, and Jennifer Henshaw. Advice and insights fromfirst author’s PhD Supervisory Committee are greatly appreciate; thanks Sarah Finkelstein, Bill Gough, Brian Branfireun, and Nick Eyles.

Thanks to the many agency staff from OMNR and Conservation Authorities who responded to our information requests, including BrynnUpsdell, Kari Jean, and Ross Willson (ABCA); Peter Dragunas and Tony Difazio (CCCA); Shannon Wood and David Pybus (SVCA);Glenn Switzer (NVCA); Muriel Andreae and Rick Batterson (SCRCA); Joe Gordon and Brian Widner (KCCA); and Kent Todd (OMNR).

Annable, W.K. (1996). . Toronto, Ontario Ministry of Natural Resources, 92 p.Annable, W.K., Lounder, V.G., and Watson, C.C. (2011). Estimating channel-forming discharge in urban watercourses. , 738-753.

Bagnold, R.A. (1966). . U.S. Geological Survey Professional Paper, , pp. 1–37.

Chapman, L.J. and Putnam, D.F. (1984, 2007). ; Ontario Geological Survey, ISBN 978-1-4249-5158-1.Eaton, B.C., Millar, R.G., and Davidson, S. (2010). Channel patterns: Braided, anabranching, and single-thread. , 353-364.Faustini, J.M., Kaufmann, P.R., and Herlihy, A.T. (2009). Downstream variation in bankfull width of wadeable streams across conterminous United States. , 292-311.Gingras, D., Adamowski, K., and Pilon, P.J. (1994). Regional flood equations for the provinces of Ontario and Quebec. , 55-67.

Hack, J. T. (1957). , U.S. Geological Survey Professional Paper, pp. 45–97.

Leopold, L.B. and Wolman, M.G. (1957) . U.S. Geological Survey Professional Paper, 39–85.Mulvihill, C.I., Baldigo, B.P., Miller, S.J., DeKoskie, D., and DuBois, J. (2009) : U.S. Geological Survey Scientific Investigations Report 51 p.Nanson, G.C. and Croke, J.C. (1992). A genetic classification of floodplains. , 459-486.OMNR. (2008). . Water Resources Information Program, Geographic Information Branch, Ontario Ministry of Natural Resources.Parker, C., Clifford, N.J., and Thorne, C.R. (2011). Understanding the influence of slope on the threshold of coarse grain motion: Revisiting critical stream power. , 51-65.Rachol, C.M., and Boley-Morse, K. (2009). : U.S. Geological Survey Scientific Investigations Report 300 p.Sherwood, J.M. and Huitger, C.A. (2005). : U.S. Geological Survey Scientific Investigations Report 38 p.WSC. (2011). [Digital Files]. Accessed online: [May, 2011].

Morphologic relationships of rural watercourses in southern Ontario and selected field methods in fluvial geomorphologyRiver Research and Applications

An approach to the sediment transport problem from general physics

Physiography of Southern OntarioGeomorphology

GeomorphologyJournal of the American Water Resources Association

Studies of longitudinal profiles in Virginia and Maryland

River channel patterns: braided, meandering and straightBankfull discharge and channel characteristics of streams in New York StateGeomorphology

Provincial Digital Elevation Model (DEM) Version 2.0.0. Product Specification – Edition 1.1Geomorphology

Estimated bankfull discharge for selected Michigan rivers and regional hydraulic geometry curves for estimating bankfull characteristics in southern Michigan riversBankfull characteristics of Ohio streams and their relation to peak stream-flows

Water Survey of Canada hydrometric monitoring program - HYDAT Database, Environment Canada

27:

422 I

Miscellaneous Release--Data 228

120:

108:

30:

294 B:

282B:

2009–5144:

4:

126:

2009–5133:

2005–5153:

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http://www.ec.gc.ca/rhc-wsc

Stream networks of southern Ontario are carved into a complex architecture ofglacial landforms and sediments, draining to base-levels of the lower Great Lakes(Huron, Erie, Ontario). These fluvial systems have evolved over relatively shortgeologic timescales of about ten thousand years, with longitudinal profiles andboundary materials still strongly conditioned by the glacial landscape. Based onlongitudinal profiles derived from the 10 metre provincial digital elevation model(DEM version 2.0.0; OMNR, 2008), potential stream power is mapped for eleven(11) major river catchments across southern Ontario . Due to multi-scalevariance in raw DEM stream gradients from both real and artifact sources, verticalslice and multi-pass moving window approaches are used to generalize channelslope to the reach scale (typically 1 – 2 km, as a representative spatial scale forfluvial processes operating over long time periods).

Results of a slope-area analysis demonstrate that fluvial channels may be over-steepened or under-steepened in association with glacial landform classifications.Specific stream power ( ) results generally fall within the theoretical domain forsingle-channel meandering rivers, with an “average” condition of = 30 Wm .Despite higher stream powers in some reaches, single-channel meandering fluvialplanforms still dominate the landscape of southern Ontario due to the moderatingeffects of: bed material sediment calibre from inherited coarse-grained valley fillslimiting fluvial bedload transport; and/or bank strength controlled by sedimentcohesion and vegetation. Understanding the spatial properties of stream powercan provide insights into regional patterns of sediment transport and alluvialfloodplain development, relevant to applied aspects of aquatic ecology, archeology,erosion assessment, stream restoration, and urban storm water management.

(Figure 1)

1)

2)

ωω

-2

From mapping of specific stream power ( ), a sample of 117reaches were selected and classified based on glacial landforms byChapman and Putnam (1984, 2007). Results of a slope-area analysisdemonstrate that fluvial channels may be over-steepened (e.g,moraines) or under-steepened (e.g., till plains, glaciolacustrine plains)in association with glacial landform classifications ( ).Specific stream power ( ) results generally fall within the theoreticaldomain for single-channel meandering rivers (10 - 60 Wm ; Nansonand Croke, 1992), with an “average” condition of = 30 Wm .Constant stream power curves for southern Ontario (based on Eq.’s 1,2, and 3) plot on a slope-area graph with a slope exponent of -0.4(Leopold and Wolman, 1957). Despite higher stream powers in somereaches which are often associated with multiple-channel planforms,single-channel meandering fluvial planforms still dominate thelandscape of southern Ontario due to the moderating effects of bedmaterial sediment calibre and bank strength.

Systematic decreases in bed material size downstream are frequentlyinterrupted by glacial landforms and sediments, in some cases withinherited coarse-grained valley fills limiting fluvial bedload transport.Expected downstream variations in grain size for a theoretical“graded” profile have been previously described by Hack (1957), as

Figure 1

Figure 6A

ω

ω

-2

-2

summarized in and presented in . Limitations onbedload transport, particularly in cobble dominated channels, willsuppress bar development and thus multiple-channel planforms.

where M is the median particle size in mm (Hack, 1957). Also, highrelative bank strength, controlled by sediment cohesion andvegetation, will limit formation of multiple channels by restricting bankerosion and channel widening. As demonstrated in , manysingle-channel reaches fall above the multiple-channel anabranching

threshold (s*, ) for low relative bank strength ( ’ = 1); however,they tend to be consistent with the single-channel meandering domain

for higher bank strengths ( ’ 2) (Eaton 2010).

where s* is the critical threshold slope for multiple-channel

anabranching, ’ is dimensionless relative bank strength, and Q* isdimensionless discharge (Q*) (Eaton 2010).

The spatial properties of stream power can contribute tounderstanding regional patterns of sediment transport and alluvialfloodplain development, with application to many other disciplines.

Eq. 4 Figure 6B

Figure 6C

Eq. 5

s = 0.006 (M/A ) (Eq. 4)

s* = 0.40 ’1.41 Q* (Eq. 5)

d

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