Geomatics Tools for Inventorying and Assessing Headwaters

1. Geomatics Tools for Inventorying and Assessing Headwaters Adam Hogg Inventory Monitoring & Assessment, Ministry of Natural Resources Eastern Region Headwaters Streams Workshop February 25, 2011

2. Outline • Presentation Objectives • My Background • How do we define headwaters? • Geomatics and Headwaters: inventorying and assessing • Summary

3. Presentation Objectives • To describe the spatial tools available for inventorying and assessing headwater areas (systems) and streams at local and regional (provincial) scales • To show an example application of a regional scale inventorying and assessing tool

4. My Background • A provincial role obtaining 10 years experience focused on regional land cover mapping using ELC, focus on wetlands • Instruction of geomatics related components of numerous courses: • Ontario Wetland Evaluation System • ELC • Fleming College Advanced Remote Sensing • Attended Temperate Headwater Wetland Restoration course • Last 3 years have been focused primarily on Ontario’s Far North

6. Geomatics and Headwaters: Inventorying, Monitoring and Assessing

7. How Do We Define Headwaters? • Interest in a spatial perspective • Excellent direction from The Natural Functions of Headwater Features: A Literature Review (TRCA, 2007) • Distinction between headwater streams and systems (areas) • Streams: “primarily ill-defined non-permanently flowing features in the upper reaches of catchments” • Systems: these streams and the catchment areas that flow into them

8. Inventorying Headwater Streams • Large scale digital air photography and elevation • Orthophotography requires large scale DEM • Digital stereo imagery requires “estimation” under tree canopy • Recent stereo imagery will be available for Eastern Ontario and South Western Ontario (DRAPE / SWOOP) • Time consuming and heavy reliance on experienced interpreters • Water Resource Information Project and Conservation Ontario leading development of large scale mapping specifications (draft complete March 31, 2011) • Capture of all “features where water is observed on imagery” are mandatory to meet the spec • Ephemeral, intermittent and perennial codes “if desired”

9. Inventorying Headwater Streams: Interpretive Approach • Spring photo’s ideal • Existing stream data • Hydrologic indicators • Understand the topography

10. “Flow accumulation” Topographic Index (Beven & Kirkby, 1978) flow accumulation local slope soil conductivity? Inventorying Headwater Streams: Surface Flow Modelling Source: Gomi et al. 2002

11. Case Example: North Carolina • Mapping Headwater Streams: Intermittent and Perennial Headwater Stream Model Development and Spatial Application (Russell, 2008) • Use high precision DEM for first and second order stream prediction • Survey grade GPS mapping for calibration and accuracy assessment • Successes: • Spatially accurate, presence absence, length of permanent streams • Challenges: • Commission error, stream length of non-perennial streams, labeling of permanence

12. Inventorying Headwater Streams: Validation of Either Method • Very challenging to validate • Requires spatially precise field sampling • Field Operations Manual for Assessing the Hydrologic Permanence of Headwater Streams (Fritz K.M., Johnson, B.R. and D.M. Walters. 2006) • Sample design • Physical and biological sampling

13. Streams & DEM’s Orthophotos Acquired (Drape) Data Available For Southern Ontario: A Provincial Perspective

14. Inventorying Headwater Systems • Headwater system: the catchment area defined by stream order and/or contributing area • More conducive to regional data, methods and planning • Correspondence between headwater streams and provincial inventory is unknown • An area based approach is more attractive

15. Assessing Headwater Systems • Engaged in a pilot project to develop a “headwater wetland database” decision support tool • A regional decision support tool that consists of headwater areas summarized by SOLRIS land cover and topographic modelling: • Existing wetland • Potential wetland • Land use

16. Headwater Decision Support Tool Restoration Mitigation Protection Note: source SOLRIS wetlands

17. Headwater Decision Support Tool Restoration Mitigation Protection Note: Source topographic index

18. Headwater Decision Support Tool Restoration Mitigation Protection Note: source SOLRIS frequently tilled agriculture

19. Headwater Decision Support Tool Restoration Mitigation Protection Note: Source untilled SOLRIS agriculture

20. Prevent development Cyan Ellipse: Development Mitigation Magenta Ellipse: Protection Blue Ellipse: Restoration Headwater Decision Support Tool

21. Inventorying And Assessing Headwater Systems • Engaged in a collaborative co-op project involving Fleming College and the Ontario Headwaters Institute: • To better understand the unknowns about provincial scale data • Develop a “first cut” at a Southern Ontario approach • Extend pilot decision support tool to Oak Ridges Moraine • Provide mapping examples for OHI website • A long term (recurring) intent

22. Summary

23. Summary • It is possible to map headwater streams: • Two potential ways of doing it • Will be challenging and potentially time consuming depending on project objectives and scale • Rigorous field calibration and validation is crucial • Regional mapping focusing on headwater systems • Simple assessment summaries and data organization can inform decision making

24. Questions?