FE 423 - Watershed AnalysisLecture 1a - Overview

Finn KrogstadUW Forest Engineering

http://students.washington.edu

OVERVIEW• why -• what -• when -• where - • how -• who -

EARLY MANAGEMENT• Management was done with little

consideration of environmental impacts

Early Regulations• Case-by-case evaluation of roads, harvests,

and locations

• Still dominates forest management today

Watershed AnalysisAPPROACH - basin specific•where are the hazards•what are they sensitive to•will they reach the stream•are there sensitive reaches•are vulnerable fish there•do inputs exceed background

Watershed AnalysisPROBLEMS•Massive expert time•Site-by-site investigation •Stop being watershed specific•Site, not landscape plans•Is plan A worse than plan B?

Goal: Comparing Landscape Options

OVERVIEW• why - spatial approach • what -• when -• where - • how -• who -

WATERSHEDS

• Spatial Heterogeneity

• Water Flows Downhill

EACH POINT HAS UNIQUE:• Vegetation• Soil• Slope• Aspect• Upslope Area• Distance to Stream• Management

‘DOWNHILL’ IMPACTS• Saturating Hillslopes• Erosion Runoff Filtering• Stream Flow Volumes• Stream Width & Depth• Sediment Supply• Fish Habitat

WE NEED1a. Data for each point in the watershed1b. Calculate processes at each point2a. Sum outputs from upslope area2b. Sum ‘delivery costs’ to stream

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Spreadsheets - The Most Powerful Scientific Tool Ever Developed

1. Bring in data2. Run calculations3. Display results

Originally was:Programming for Accountants

GRID: the Spreadsheet for Landscapes

1. Bring in spatial data (soils, vegetation, topography, )

2. Run equations3. Display results

ArcView: not just pretty pictures

Watershed Analysis: in GRID

•data for each point•calculation at each point•… along path to the stream•accumulating upstream inputs•accumulating different inputs•compare management plans

Gridding the World

OVERVIEW• why - spatial approach • what - downhill in GIS• when -• where - • how -• who -

SCHEDULETuesday Thursday

Grid Basics overview spatial datadigital topography surface functionsgrid algebra grid functions

Grid Hydrology Exam I flow directionflow accumulation path lengtheuclidian/costpath vehicular trafficwildlife movement Exam II

Grid Watersheds mass wasting surface erosionhydrology channelsriparian fish

Finals Week Final Exam

OVERVIEW• why - spatial approach • what - downhill in GIS• when - schedule• where - • how -• who -

SYLLABUS

OSB

OVERVIEW• why - spatial approach • what - downhill in GIS• when - schedule• where - OSB 111• how -• who -

SYLLABUSInstructors: Finn Krogstad, Peter Schiess

Grading:FE423: three exams (33% each)FE523: three exams and a project (25% each)

Lectures: Tuesday & Thursday, 9:30-11:20, in OSB 111 (except first day in AND 302)

Exams:Each exam will include an in-class and a take-home part. The in-class part is open book, open note, pencil-and-paper discussion of grid-based solution of watershed problems. The take-home part which will require solution of problems.

Practice Problems:Each lecture will include a set of problems to provide hands-on experience in the grid-based approach to solving watershed problems. These problems are not handed in, but the exams will look much like these problems, and will assume that students have completed all problems.

READINGS• Hard copy of the online help

Cell Based Modeling with GRID• People without ArcView experience

Getting to know ArcView GIS• Another view of Spatial Analyst

Extending Arcview GIS • Some Hydrology and Geomorphology

Water in Environmental Planning, Watershed Analysis Manual (WFPB)Geomorphology (Chorley, et al)

OVERVIEW• why - spatial approach • what - downhill in GIS• when - schedule• where - OSB 111• how - syllabus• who -

Why Watershed Analysis in GRID?

PROBLEMS• not a survey class: an approach, not ‘facts’• learning GIS: requires work• existing software: more accurate ‘black boxes’

ADVANTAGES• quantitative approach: actually ‘say something’• insight into process: applicable to many issues• GIS skills: applicable to other types of problems

Should you take this course?

• Spatial Hydrology• Landscape Scale• More GIS

Discussion Problems:for Thursday, try and be ready to discuss the following

Make a spreadsheet that will estimate the peak flow Q5=.157*A.9*Pa1.35*F-.21 for a five year storm in Region XII, using a table of road crossings with their respective contributing area A, percent forest cover F, and annual rainfall Pa.