Millicoma Meander, Elliott State Forest, Oregon

Science Center Objects

Recent Conditions

Instruments were installed in late summer 2012 and are used to monitor and detect changes in local conditions, including

Displayed measurements are taken at 1-minute intervals and transmitted hourly during daylight hours to be displayed on graphs.

Purpose of Monitoring

Landslides in the Oregon Coast Range impact people and the environment and are commonly induced by intense or prolonged rainfall associated with strong storms in the late fall and winter season. For example, in February and November of 1996 heavy rainfall from two unusually large storms induced thousands of landslides over a large part of western Oregon.

The USGS and its cooperators have installed instruments in a steep, recently clear-cut basin in the Elliott State Forest. Data collection at this site supports research on hydrologic factors that control landslide initiation, debris-flow timing, and debris-flow magnitude. In many landslide-prone hillsides, infiltration of water from rainfall or snowmelt increases ground-water pressures. These elevated pressures can, in turn, induce landslide movement which can lead to debris-flows.

 

Two maps of the Millicoma Meander Study Basin showing where monitoring sensors are and the slope

Locations of instrument stations overlain on topographic contour and slope maps of the Millicoma Meander drainage basin.

(Public domain.)

 

Data logger suspended above a channel with a person pointing up at it from the bottom of the channel

Photograph of the channel station showing the laser distance meter (in red circle) high above the channel used to measure stage (height) of flow in the channel.

(Public domain.)