FEMA Region X – Risk MAP Discovery Interview
Lower Willamette - Tualatin Watersheds
Clackamas County, Oregon
August 15, 2012; 1:00pm Pacific Time
Clackamas County
Steve Hanschka – Planning
Jay Wilson – Hazard Mitigation Coordinator
Rebecca (Becky) Ceniga – Floodplain Manager
Eric Bohard – GIS Administrator
FEMA Region X
Dave Ratté – Regional Engineer
Oregon DLCD
Steve Lucker – State Risk MAP Coordinator
STARR (FEMA Contractor)
Becca Croft – Interviewer
Jason Sidorski – GIS Specialist
Jennifer Anticknap – Recorder
The following information was collected during the Interview. Unless otherwise noted, all comments are
from Clackamas County representatives.
I.
Contacts
 M. McCallister, Planning Director was updated on the contact list. The County requests
Mr. McCallister be invited to the Discovery meeting and receive copies of project
correspondence.
 Addresses and telephone numbers were added and updated.
STARR (J. Sidorski) reviewed the GIS data that has been collected for the Clackamas County and
explained the types of additional data that could be beneficial to the project: parks, environmentally
sensitive areas, critical habitats, building footprints, parcels, topographic data (LiDAR, etc.).
II.
III.
Topography, LiDAR, and GIS
 E. Bohard is the County GIS contact. The County is willing to share all available GIS data.
 S. Lucker will coordinate with E. Bohard to obtain all relevant GIS data, including but not
limited to; parcels, watershed boundaries, jurisdictional boundaries, etc.
 The County is willing to conduct a GIS exercise to identify specific areas of concerns and
will provide GIS files.
Planning
 Clackamas County is currently updating their Hazard Mitigation Plan (HMP). This will be
the second update to this plan and is expected to be re-adopted in October 2012.
 The HMP identifies mitigation projects completed within the last 5-years.
Mitigation projects occur in smaller basins (Abernathy and Sandy basins).
Risk MAP Discovery Interview – Lower Willamette - Tualatin Watersheds
Clackamas County – August 15, 2012
IV.
V.
VI.
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 The plan identifies flood prone areas in the Lower Willamette and Tualatin
Watersheds where opportunities for future mitigation actions could take place.
 Repetitive loss structures are noted in the plan (place names and along streams
used for identification) and do exist in Clackamas County, specific addresses of
repetitive loss properties are not listed in the plan.
 The HMP is for Clackamas County only, it is not formally multi-jurisdictional. However,
cities, like Lake Oswego which have their own plan, have addenda to the Clackamas
County plan. The City plans are sovereign from the County plan.
 One of the planning challenges Clackamas County faces is they do not have floodplain
management plan for CRS Program, they rely on the HMP to fit in for that. If there is
support/assistance to create a separate floodplain management on a short turn-around
time (in the next 4weeks) that could help CRS then it would be helpful.
Earthquakes
 The County identified an area in the northern portion of the county where faults exist
(captured in the Areas of Concern layer).
 Earthquake damage resulted from the 1993, Scotts Mills Earthquake (“Spring Break
Quake”) in the southern portion of the county. The earthquake caused brick failure at
local high schools near the Marion County line. J. Wilson has an after action report on
this earthquake that outlines earthquake mitigation strategies that he is willing to
provide.
 There has been County infrastructure that has been retrofitted. J. Wilson could provide
a list of infrastructure retrofitted under HMPG and other grants.
 The County noted there are a number of areas down around the river channels (along
the Lower Willamette and Tualatin Rivers and Lake Oswego area and in the Cities of
Lake Oswego and West Linn) that are prone to ground failure, liquefaction, lateral
spreading, and differential settlement especially during an earthquake.
Wildfires
 There could be areas along the urban-rural interface, specifically around the Cities of
West Linn, Lake Oswego, and Milwaukie that could be at risk.
 Clackamas County is currently updating the Wildfire Protection Plan.
 The County asked for a copy of the watershed boundaries being used for this project
and they would in turn provide information regarding wildfire risk and mitigation in the
project area.
Landslides
 The County uses DOGAMI data for landslide risk and information. DOGAMI is currently
updating landslide inventory and has a received a grant to study landslide susceptibility
using LiDAR so this data is not currently readily available.
 The County Roads Department does maintain a database of roads with active landslides
they are willing to provide.
 The County will be able to provide landslide hazards maps based on soils and slopes.
Risk MAP Discovery Interview – Lower Willamette - Tualatin Watersheds
Clackamas County – August 15, 2012
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VII.
VIII.
Page 3 of 4
The County identified general landslide areas along the Willamette River, starting
approximately at the City of Gladstone northward to approximately the outlet for Lake
Oswego (captured in the Areas of Concern layer). Additional area, southeast of the City
of Milwaukie along the Clackamas River was captured in the Areas of Concern layer.
D. Ratte mentioned that any concerns the County may have in the Sandy Basin can also
be forwarded along since the study is on-going.
 The County is most active in the post-flood areas of the Sandy Basin.
Severe Storms
 Snow impacts are considered minimal and typically concentrated at the higher
elevations. The county is 45-50ft in elevation above sea level.
 In the winter storm of 2008 (10+ day storm) damage was concentrated in Johnson City
(manufactured home community) where a number of awnings collapsed.
 Ice storms are of particular concern because of transportation impacts on roads in areas
of steep slopes. Roads in these areas become impassable and impacts are compounded
when ice storms coincide with snow events.
 The County is not aware of any significant power outages where residents would have
to be sheltered. Power is typically restored within hours for urbanized area (48 hours is
typically the standard), in rural areas it may take a little longer but no need to open
shelters.
 Most of the recent development in the rural areas (mostly in the Tualatin Watershed) is
subject to the State of Oregon building code. The building code is conservative and has
been effective in meeting the environmental challenges to prevent residential damage
to structures. Structures in these rural areas are built to withstand damage from
wind/snow events.
 The County works with National Weather Service for forecasts and preparations in
advance of a winter storm event.
 Afterwards, the County conducts outreach through media via the Public Information
Office.
 They also have an online disaster reporting service for residents which enables initial
damage assessments.
Flooding
 The County has repetitive loss inventory data from 2008. S. Lucker noted he has more
recent data and will provide to the County.
 The Tualatin River was recently restudied to mouth of Willamette River so the County
has no issues with the modeling or floodplain along there.
 The Willamette River, even though the modeling was done in the 1970’s appears to be
reasonable and reflect the actual extents of flooding.
 The county’s main flooding issues are in the Sandy Basin.
Risk MAP Discovery Interview – Lower Willamette - Tualatin Watersheds
Clackamas County – August 15, 2012
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IX.
X.
XI.
XII.
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The County did note significant storm drain issues in the Oak Lodge Sanitary District.
These areas are not mapped and are significantly prone to run off and flooding. The
County identified this general area in the Areas of Concern layer.
 The County identified three streams that are flood significantly as a result of street runoff: Mount Scott Creek, Johnson Creek, and Kellogg Creek.
 The County will follow-up and provide specific areas of flooding concern.
D. Ratte noted Lake Oswego is currently going through a Physical Map Revision,
responding to a question from the County whether Lake Oswego would be restudied
through this project.
Levees
 Due to time constraints this topic was not covered during this call. The County will
provide hazard risk and mitigation information as applicable as a part of the GIS data
transmittal.
Environmentally Sensitive Areas
 Due to time constraints this topic was not covered during this call. The County will
provide hazard risk and mitigation information as applicable as a part of the GIS data
transmittal.
Communications and Outreach
 Due to time constraints this topic was not covered during this call. Follow-up during the
Discovery meeting is required.
 Mention of the Public Information Office and on-line disaster reporting system was
made during the discussion on Severe Storms.
Other
 County has had preliminary discussions with Christine Shirley (DLCD, Oregon NFIP
Coordinator) about training for flood insurance agents in the County but has not
followed up. Item noted for discussion during the Discovery meeting.