3.0 Rationale – Why the need for watershed management tools?
1.0 Abstract
• The purpose of this poster is to provide an overview of a GIS data
framework and a suite of hydrology tools being developed to support
watershed management in Alberta.
• The poster outlines the rationale and vision for the work, progress to
date, and highlights some examples that show data quality and utility.
• Project milestones include:
- progress on a GIS database using an ArcHydro framework;
- enhancements on DEMs and live update on time-series data;
- development of tools to delineate watersheds and extract key
watershed characteristics and data; and
- coupling ArcHydro capabilities with hydrology models.
2.0 Background
• The Province of Alberta includes
some of the most diverse terrain and
waterscapes in North America.
• Totaling 661,000 km2, Alberta’s
landscapes vary from hot dry
badlands, vast unbroken forests,
alpine tundra, massive icefields, rich
agricultural lands to rolling grasslands.
• These landscapes are also home to
a rich diversity of plants, mammals,
birds, reptiles and amphibians.
• Alberta is also a busy place and is
facing significant pressure on its
biodiversity, air, land and water
resources!
• Pressures include activities related
to hydrocarbon recovery, agriculture,
forestry, mining, expanding
settlements, water control structures,
municipal and industrial discharges,
and linear disturbance such as
transportation, pipelines and seismic
exploration.
• These pressures pose complex
social, economic and environmental
challenges.
Factors Influencing the Variability of
Alberta’s Natural Environments
• Water for Life: Alberta’s Strategy for Sustainability endorsed a partnership approach to
watershed planning and management.
• As seven established Watershed Planning and
Advisory Councils (WPACs) become mature over
time, their planning tools and requirements will
become increasingly more complex (e.g. near
real-time modelling).
• Alberta is leading the way to develop, design,
and implement integrated resource (air, land,
water & biodiversity) management plans to meet
the Land Use Framework’s legislated mandate.
• GIS and ArcHydro provide a strong foundation
and start point for progress down this path, and
are well suited to the adaptive management challenges of Alberta.
4.0 Vision – ArcHydro as a Foundation for Watershed Management
GIS:
HYDAT
Visualize, manage,
manipulate, analyze, and
help to model temporal
and spatial processes
WISKI
Natural
Region
Elevation
Surficial
Geology
Climate
Permafrost
Extent
Drainage
Areas
Hydrogaphy
Ground
Water
Dominant
Soil
Streams &
Monitoring
Channels
Alberta ArcHydro Framework
Surface
Terrain
Dominant
Vegetation
Water
Quality
Rainfall
& Snow
OrthoPhotography
EMS
Water
Deficit
Growing
Season
Runoff
Data accessed through GoA Citrix and
Canada Internet Map Service
Water Use
Land Cover/Use
Time Series Data
Naturalized
Flow
Understanding the Pressures on
Alberta’s Natural Environments
ArcHydro
Geodatabases
Enterprise
Data Warehouse
Settled Areas &
Transportation
Dams and
Control
Structures
Point Source
Return Flows
Air, Land and
Biodiversity
Geospatial Data
Soil
ArcHydro
Tools
Geology
Remote
Sensing
Automated Watershed
Delineation & Characterization
LiDAR
3,500
Alberta
Manitoba
Saskatchewan
Modelling Interfaces
2,500
Pipelines
Forest
Tenures
Municipal
Districts
& Counties
2,000
Water Resources Models
1,500
1,000
Water allocation (e.g., AWAIT)
SOE reporting
500
0
1950
125
1960
1970
1980
1990
2000
2010
Sand, Gravel
& Aggregate
Hydrocarbon
Potential
Agricultural
Activity
Natural flow
100
Source(s): Statistics Canada, Censuses of
population, 1956 to 2006
(Data accessed April 12, 2007)
Desktop (Hydrological)
SSRB IFN (Holistic)
Discharge (m
Population (in 1000s)
3,000
75
50
25
Data accessed through GoA Citrix and
ministry websites
12
Naturalized flow
16
20
24
28
Week of year
32
36
40
44
48
52
IFN recommendation Flood mapping
Groundwater mapping
Water quality mapping
5.0 AB-ArcHydro: Progress to Date
• SDE geodatabases created for each of the 18 ‘major’
basins in the province (stream definition of 5 km2)
• AB-ArcHydro is currently accessed two ways:
- Stand-alone Desktop ArcGIS
- Citrix thin-client
Data Created in AB-ArcHydro
Network
•The geometric network
•The complex edge feature class
•The hydro junction of the network
• The relationship of hydro junction and
catchment watershed
Raster Data
• Raw DEM
•Filled DEM
•Flow direction
•Flow accumulation
•Stream Definition
•Stream Segmentation
•Catchment Grid
•Slope
•Slope greater than 30%
Daily Time Series Data
Vector Data
Legend
AthabascaRiver
MilkRiver
BattleRiver
NorthSaskatchewanRiver
BeaverRiver
OldmanRiver
BowRiver
PakowkiLake
BuffaloRiver
PeaceRiver
GreatSlaveLake
RedDeerRiver
HayRiver
SlaveRiver
LakeAthabasca
SoundingCreek
LiardRiver
SouthSaskatchewanRiver
AB ArcHydro example for North
Saskatchewan River Basin
Data organized into 18 major basins
•Catchment
•Drainage Line
•Adjoint Catchment
•Drainage Point
•Longest Flow Path For Catchment
•Longest Flow Path For Adj.Catchment
• Centroid of Catchment
Maidment, D.R. 2002. Arc Hydro – GIS for Water Resources, ESRI Press
•Streamflow data
•Water level data
•Precipitation data
•Snowfall data
•Rainfall data
•Temperature data
•Sunshine data
•Snow pillow data
• Humidity data
•Wind speed/direction data
• Evaporation data
• Evapotranspiration data
•Natural flow data
•Others
6.0 AB_ArcHydro: Current and Future Applications and Development
Reconciling the Provincial DEM
Live data links to Department databases
TS 2
TS 1
TS 3
TS 5
TS 4
AB_ArcHydro
• Versions 1, 3 and 4 of AB_ArcHydro were each published with a time series (TS) database of
hydrologic and climate data. Although comprehensive, the data was static in nature. Copies of
time series were used to populate the ArcHydro database, meaning that the update of new
information (and subsequent corrections to data) requires continued maintenance. The update
process depends on resource needs that are not predictable or assured.
Others
Applications
WISKI
TS 1
• While this is workable, in principle it is preferred to reference a single true source of
original data, rather than rely on standalone replications. A better solution would be to
develop permanent and open data connections to Department information systems (like
the WISKI time series manager, or the Enterprise Data Warehouse/EDW) to ensure the
most correct and up-to-date information is always presented by AB_ArcHydro.
Alberta Desktop Method Application:
Computations and Report
The “Alberta Desktop Method” Recommendation for
Environmental Flows uses historical natural flows to
come up with an instream flow recommendation that
is fully protective of the aquatic environment and in
the absence of reach specific studies. It is typically
applied on a weekly time step, meaning that there are
52 recommendations based on the weekly flow
duration curve and computed environmental baseflow
for that week. This results in fairly routine but
intensive computations, and has been automated
within an Application that functions with the
AB_ArcHydro data.
EDW
TS 5
TS 2
TS 3
TS 4
AB_ArcHydro
Applications
Coupling to Hydrologic Models
Example:
Drainage areas derived for WSC Sub-regions using pour points
and the Alberta 25m Hydrocorrected DEM (colour polygons), as
compared with prior drainage boundary delineations (black lines)
Watershed/Climatic Characteristics
ArcHydro
Geodatabases
ArcHydro
Tools
Water Budget Summary
MIKE SHE Integrated
Hydrologic Modelling
Simulated Hydrograph
Channel Characteristics
DHI (http://www.dhigroup.com)
Word Document
Summary Report
Hydrologic Stats/
Summary Charts
Weekly Flow
Recommendations
Historical
Availability Matrix
• Version 2 of AB_ArcHydro was produced using the raster
Provincial 100m DEM plus high quality hydrography (stream
network) that was burned into the DEM.
• When a Hydrocorrected 25m DEM became available it was
used for Version 4 of ArcHydro. It was presumed that since the
DEM had been resampled* with the drainage network taken
into account, this would be an improvement over ArcHydro 2.
(*the 25m grid size was resampled from the 100m DEM, by
interpolation)
• However, user acceptance testing of ArcHydro 4 data set is
ongoing as several issues have been identified with the
Hydrocorrected Provincial 25m DEM layer. For the moment,
ArcHydro 2 remains the endorsed version for watershed
delineation purposes.
A major goal for establishing a single source of hydrologyrelated time series and spatial data is to make model
development, calibration and operation quicker and easier.
Models that can process ArcHydro-compliant databases will
be able to seamlessly interface with data sources. It is
expected that ArcHydro databases and tools will support
models that estimate water budgets, compute natural flows
and simulate hydrographs in ungauged basins.
Testing of the MIKE SHE model for several pilot projects has
been undertaken (MIKE SHE does not yet directly support
ArcHydro but was planning to develop that functionality.)
Areas circled in red indicate places where the hydrocorrected DEM
is at significant variance to existing watershed delineations. In both
cases this has been tracked to likely DEM errors – canals not being
removed from the terrain – resulting in portions of the lower Bow
draining south to Oldman (pink) or north to Red Deer (green).
• A process for reconciling identified variances and known
issues arising between different topographic-based datasets
needs to be developed. This is a broader initiative than just
ArcHydro.
• It is recognized that no data set is without issues; but
migration toward a single, adequately maintained and
continually updated topographic data set for routine watershed
delineations using common digital methods and tools would
be ideal.