Tom Elliott
Tom Elliott
Project Area-Toppenish Creek on Yakama Reservation
Drastic land use changes over last 200 years-
Drastic land use changes over last 200 years-
Beaver trapping
Cattle and sheep grazing
Railroad and road development
Irrigated Agriculture
Floodplain Disconnection
LiDAR Elevation Model
Floodplain Restoration Using Grade Control
Monitoring Network
Did the project raise the floodplain water table relative to creek flows?
Did the project raise the floodplain water table relative to creek flows?
Collect and reduce data
Characterize groundwater interactions
Select wells that show creek influence
Compare water levels before and after project
completion for selected wells
Project was completed in fall of 2006
Water table March 23 2009
Toppenish Creek vs. Marion Drain
Well Data
Creek Influence on Wells
Stream Stage Data
Graphical analysis
Water levels before and after
Data Summary
Channel effects?
September 2005
July 2008
Grade control structures appear to have raised water table relative to upstream flow by at least 1 foot at low flow
Grade control structures appear to have raised water table relative to upstream flow by at least 1 foot at low flow
Project effects vary by well location
The biological significance is likely to be positive
Better data collection is necessary for future monitoring efforts
Questions?
Reichmuth, D.R., Potter, A.S., and Reichmuth, M.G., 2007, Toppenish Basin Geomorphology, Geomax, P.C.
Reichmuth, D.R., Potter, A.S., and Reichmuth, M.G., 2007, Toppenish Basin Geomorphology, Geomax, P.C.
Zar, J.H., 1999, Biostatistical Analysis, Fourth Edition: Upper Saddle River, New Jersey, Prentice-Hall, Inc., 798 p.