|County seeks statewide policy for flood hazards posted on 02/01/2019|
Jan. 16 marked the eight-year anniversary of the 2011
flooding in the upper Sandy River Basin that washed out a section of Lolo Pass
Road, undercut the Zig Zag River bridge, swept away three homes and left a
swath of property damage with over 150 residents stranded by the rampaging
During a Jan. 19 Rhododendron Community Planning
Organization (CPO) Meeting held at the Mt. Hood Oregon Resort, Jay Wilson,
resilience coordinator for Clackamas County Disaster Management, discussed
continued flood risks in the area.
“The Sandy (Basin) is just as capable and dangerous to
property in the future,” Wilson said, citing the historic flooding in 1964 that
destroyed 155 dwellings and the more recent 2011 event. “We need to have a
policy that gives us a framework to prepare for an event like this fairly.”
Wilson detailed county plans to request policy development
at the state level regarding Channel Migration Zones (CMZ) and their impact on
public safety and importance for healthy river habitats across the state. CMZ
are areas where river channels migrate laterally over time due to natural
processes of flooding and erosion. This natural movement of the river
throughout the floodplain provides a crucial breeding ground for endangered
It also provides the potential for highly erosive flooding
with risk to property. CMZ are not currently mapped by FEMA for flood insurance
purposes or regulated for development in Oregon.
Wilson described an increase in flood hazard in the
community due to new development in the CMZ, a continued risk to existing
infrastructure and the need to protect critical salmon habitat as reasons the
county is proposing a statewide CMZ policy. The county seeks a policy that
provides a legal basis for counties to make local land use regulations to limit
flood hazards and protect habitat.
“Current land use policies are allowing people to build in
areas we know are dangerous,” said Clackamas County Commissioner Jim Bernard
during the meeting. “We don’t have a policy in place to address this.”
Bernard, who was joined by fellow Commissioner Ken
Humberston, noted that Oregon disclosure laws are some of the most limited in
the country in terms of making property buyers aware of potential hazards.
“We feel like we should let people know of the potential
(flooding),” he added.
Bernard discussed a letter written by the board of
commissioners to Oregon Solutions, an organization that helps local communities
develop policy on the state level, asking for the development of an Oregon CMZ
policy group. The group will be comprised of state and federal agencies with
Clackamas County as lead sponsor and will draft proposed legislation allowing
local jurisdictions to regulate development in areas known for flooding and
“Advisory maps are out there. They just haven’t been
officially adopted on a regulatory level,” Bernard said.
Maps of the CMZ hazard zones on the upper Sandy River were
published in 2015 by the Oregon Department of Geology and Mineral Industries
(DOGAMI) using hydrologic surveys conducted with light detecting and ranging
“These surveys give scientific basis for informing
policies,” Wilson said. He added they provided a guide for regulatory overlay
on a mapped level.
Wilson stated that with county oversight of a state
certified CMZ hazard area there would be restrictions to new and existing
development, direction for bank protection and habitat conservation.
“Standards will be higher and more stringent rather than
just the existing approach,” he added. “We’re trying to think about the next 50
years … to insure a balance between natural systems and property protection.”
The Rhododendron CPO meeting marked the beginning of the
county’s public engagement regarding the proposed statewide CMZ hazard policy.
Wilson will present more information about the issue at the upcoming Mount Hood
Area Chamber of Commerce meeting, at 8 a.m. Tuesday, Feb. 5, at the Mt. Hood RV
Village Resort, 65000 Hwy. 26 in Welches.
Additional information about the CMZ and flood hazard is
available online at www.clackamas.us/dm/flooding.html.
By Benjamin Simpson/MT