This multi-factor analysis answers the question, "
Where
in the watershed are some potential floodplain restoration
sites?". Potential floodplain restoration sites
would be former floodplains (diked, drained, or otherwise
altered) that do not have land uses incompatible with
floodplain restoration.To locate potential floodplains,
we used the DEM-derived slope layer and the DLCD generalized
zoning layer. We removed from consideration all stream
segments that passed through property zoned as "urban",
"rural residential", rural industrial", "rural commercial",
and "rural service center" since these are unlikely areas
for restoration projects.
Since it probably would not be practical to attempt to
restore floodplains along very short segments of streams,
we then selected those stream segments longer than 500m
that flowed through these 'flat areas.' (In case the Council
wishes to conduct further analyses using these data, we
retained the shorter segments in the layer, but simply
selected those longer than 500m for summarization and
display on the maps).
Basin Insert Maps:
Alsea,
Ocean Tributaries,
Salmon,
Siletz,
Yachats, and
Yaquina.
Before summarizing this information
in GIS layer, we manually removed stream segments where
there was a lot of "flagging" on the derived streams layer
(see Appendix A).
Please address questions or comments
to:
Dr. Ralph Garono
Principal Investigator
Earth Design Consultants, Inc.
rgarono@earthdesign.com
Laura Brophy
Principal Investigator
Green Point Consulting
brophyl@peak.org |
homepage 
