?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F9795%2F&rft.title=Refinements+on+a+GIS-Based%2C+Spatially+Distributed+Rainfall-Runoff+Model+for+a+Small+Watershed&rft.creator=Swensson%2C+Matthew+T&rft.description=This+research+addresses+the+problem+of+predicting+the+direct+runoff+generated+by+precipitation+falling+over+a+small+watershed+using+an+existing+rainfall-runoff+model.+The+model+consists+of+several+separate+modules%2C+which+process+data+describing+the+spatial+variation+of+watershed+properties%2C+and+compute+the+runoff+time+series+at+the+watershed+outlet.+Data+processing+and+visualization+is+handled+primarily+by+GIS+software%2C+while+computer+programs+perform+the+bulk+of+the+computations.+The+model+is+designed+to+operate+a+simply+and+generally+as+possible%2C+requiring+only+four+external+data+sets+as+input+(Digital+Elevation+Model+(DEM)%2C+land+coverage%2C+soil+coverage%2C+and+incremental+precipitation+depths)+to+create+all+other+data+needed+to+compute+the+direct+runoff+for+the+watershed+under+study.+Our+goal+is+to+improve+the+model+by+refining+the+existing+programs+and+increasing+the+level+of+spatial+distribution.To+achieve+this+goal%2C+we+focus+our+research+on+the+following+three+objectives%3A+testing+and+refining+the+existing+model%3B+developing+a+hydraulic+flow+routing+module+using+the+Kinematic+Wave+model%3B+and+exploring+the+possibility+of+calibrating+the+model+results+to+the+actual+soil+moisture+conditions+present+in+the+watershed+during+the+time+of+interest+by+modifying+the+SCS+curve+number+values+across+the+watershed.+We+consider+Little+Pine+Creek+watershed+located+in+Allegheny+County+as+our+case+study%2C+and+compare+the+model's+predictions+for+two+separate+precipitation+events+with+the+direct+runoff+hydrographs+given+by+a+USGS+stream+gauge+located+at+the+outlet+of+the+Little+Pine+Creek+watershed.+Based+on+the+results+of+our+investigation+we+identify+and+correct+several+problems+with+the+existing+model%2C+and+provide+a+better+understanding+of+how+the+model+responds+under+varying+conditions+and+assumptions.+We+show+that+the+Kinematic+Wave+flow+routing+model+does+not+work+well+with+our+model+because+is+cannot+account+for+storage+within+the+watershed.+We+also+develop+an+effective+method+for+calibrating+the+volume+of+runoff+predicted+by+the+model+to+that+given+by+the+USGS+stream+gauge+by+adjusting+the+SCS+curve+number+values+in+the+watershed+to+reflect+that+actual+soil+moisture+conditions+present+at+the+time+of+interest%2C+guaranteeing+that+fluid+mass+is+conserved+between+our+model+predictions+and+reality.&rft.date=2004-02-02&rft.type=University+of+Pittsburgh+ETD&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F9795%2F1%2Fswenssonmatthew120403.pdf&rft.identifier=++Swensson%2C+Matthew+T++(2004)+Refinements+on+a+GIS-Based%2C+Spatially+Distributed+Rainfall-Runoff+Model+for+a+Small+Watershed.++Master's+Thesis%2C+University+of+Pittsburgh.++++(Unpublished)++