Functional linkage of watersheds and streams: ArcGIS FLoWS tools David Theobald, John Norman, Erin Poston, Silvio Ferraz Natural Resource Ecology Lab, Dept of Recreation & Tourism, Colorado State University Fort Collins, CO USA 26 July 2005

Project context Challenges of STARMAP (EPA STAR): Challenges of STARMAP (EPA STAR): Addressing science needs Clean Water Act Addressing science needs Clean Water Act Integrate science with states/tribes needs Integrate science with states/tribes needs Assisting statisticians to test tenable hypotheses generated using understanding of ecological processes Assisting statisticians to test tenable hypotheses generated using understanding of ecological processes Goal: to find measures that more closely represent our understanding of how ecological processes are operating

From watersheds/catchments as hierarchical, overlapping regions… River continuum concept (Vannote et al. 1980)

… to network of catchments Benda et al. BioScience 2004

SCALE: Grain Substrate Biotic Condition Overhanging Vegetation Segment River Network Network Connectivity Tributary Size Differences Network Geometry Stream Network Connectivity Flow Direction Network Configuration Drainage Density Confluence Density Cross Sectional Area Channel Slope, Bed Materials Large Woody Debris Biotic Condition, Substrate Type, Overlapping Vegetation Detritus, Macrophytes Microhabitat Segment Contributing Area Riparian Vegetation Type & Condition Floodplain / Valley Floor Width Localized Disturbances Land Use/ Land Cover Landscape Climate Atmospheric deposition Geology Topography Soil Type Microhabitat Shading Detritus Inputs Riparian Zone Nested Watersheds Land Use Topography Vegetation Type Basin Shape/Size COARSE FINE Reach

USGS NHD, NED

FLoWS v1 tools for ArcGIS v9.0… FLoWS v1 tools for ArcGIS v9.0… Will migrate to v9.1 Will migrate to v9.1

Pre-processing segment contributing areas (SCAs) Automated delineation Inputs: Inputs: stream network (from USGS NHD 1:100K) stream network (from USGS NHD 1:100K) topography (USGS NED, 30 m) topography (USGS NED, 30 m) Process: Process: “Grow” contributing area away from segment until ridgeline “Grow” contributing area away from segment until ridgeline Uses WATERSHED command Uses WATERSHED command “true” catchments “adjoint” catchments Segments

Segments are linked to catchments 1 to 1 relationship 1 to 1 relationship Properties of the watershed can be linked to network for accumulation operation Properties of the watershed can be linked to network for accumulation operation

Landscape networks with Python Need to represent relationships between features Need to represent relationships between features Using graph theory, networks Using graph theory, networks Retain tie to geometry of features Retain tie to geometry of features Flow relationships table (like NHD, but flow-sorted!) Flow relationships table (like NHD, but flow-sorted!) Implementation in ArcGIS Implementation in ArcGIS Geometric Networks (ESRI – complicated, slow) Geometric Networks (ESRI – complicated, slow) Landscape Networks: Open, simple, fast Landscape Networks: Open, simple, fast Began with VBA (1.5 years), moved to Python (2 months) Began with VBA (1.5 years), moved to Python (2 months)

Selections Downstream Downstream

Example: Flow modification Deynesius and Nilsson, Science (1994) – 77% of upper 1/3 of northern hemisphere rivers are strongly or moderately affected - F = regulated/total channel length - R = % of VMAD (cumulative reservoir live, gross capacity) Network-based flow modification 1. Degree of modification to flow = cumulative annual flow – cum. dam max. storage: Q’ = Q-S 2. Proportion of modified to VMAD (“natural”) flow: F = Q’/Q Collaboration with Aquatic ecologists (Poff, Merritt) RCL TCL

High Dam “shadow” Reservoirs 1. DEM 2. Slope 3. Flow dir. 4. Flow acc. 5. Hydro dist.

Example: Coho salmon distances

Example: 2D stream in Virginia

Next steps Increase range of applications Increase range of applications Attach additional datasets to SCA database Attach additional datasets to SCA database Land cover (urban, ag, “natural”) Land cover (urban, ag, “natural”) Historical, current, future housing density Historical, current, future housing density Indexing of National Inventory of Dams? Indexing of National Inventory of Dams? From segments to geomorphological reaches, gradient From segments to geomorphological reaches, gradient Project/tool website: Project/tool website:

Thanks! Comments? Questions? Comments? Questions? Funding/Disclaimer: The work reported here was developed under the STAR Research Assistance Agreement CR awarded by the U.S. Environmental Protection Agency (EPA) to Colorado State University. This presentation has not been formally reviewed by EPA. The views expressed here are solely those of the presenter and STARMAP, the Program (s)he represents. EPA does not endorse any products or commercial services mentioned in this presentation. Funding/Disclaimer: The work reported here was developed under the STAR Research Assistance Agreement CR awarded by the U.S. Environmental Protection Agency (EPA) to Colorado State University. This presentation has not been formally reviewed by EPA. The views expressed here are solely those of the presenter and STARMAP, the Program (s)he represents. EPA does not endorse any products or commercial services mentioned in this presentation. FLoWS: starmap FLoWS: starmap starmap starmap CR