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This information was collected by Matt Erickson, graduate student at the University of Montana.  This information has not been published, nor peer reviewed.  It is presented here as evidence that a  current, formal assessment of Ashley Creek needs to be preformed.

Summary of Data  Map of  Study Site  

A Brief Summary of a Reinventory of a Section of Ashley Creek

Matt Erickson

Environmental Studies Master’s of Science Candidate

 University of Montana

 In 1987 the Flathead Conservation District, with assistance from the Montana Department of Health and Environmental Sciences, Water Quality Bureau, and Montana Department of Fish Wildlife and Parks, performed an inventory of Ashley Creek in Northwestern Montana.  The assessment involved the use of aerial photos and a stream inventory form.  In June of 1987 team members walked the length of Ashley creek observing impacts on the stream.  Those impacts were then superimposed on the aerial photos.  The results of this inventory were summarized in Living with Ashley Creek, n put out by the Flathead Conservation District in 1987.

            The aerial photos and the raw data sheets were used to reinventory Ashley Creek in November of 2000.   This report focuses on streambank structure using the same criteria that the 1987 inventory used.  

The following information focuses on a section of the stream between Ashley Lake and Lone Lake.   The section is related to aerial photos 101-104.  Due to time constraints, this section was chosen for its relative ease of access and its high number of impacts noted in the 1987 inventory (see attached map for approximate location of observations).  Doug Gamma provided the access to this section of the creek, by allowing access through his property.  The sites of impact noted in 1987 related to stream structure were revisited.  The data was collected, photos were taken of the site and GPS units were recorded.  In addition to the impacted sites that the 1987 inventory observed, any additional impacts were noted, photographed, and GPS position recorded (perhaps new or not previously recorded sites).

The data is summarized in Table 1 and Table 2.  A comparison between the data of the 1987 inventory and the 2000 data reveals that the stream bank structure has degraded over the past 13 years.  A change from 6% of eroding stream banks that were failing to 46% was observed.   This correlates with an increase in the amount of riprap on the order of 351 feet.

  Ashley Creek tends to meander quite a bit through this section, but the impact of heavy grazing up to the stream bank has caused a large increase in stream bank failure.  There is a section of creek between Doug Gamma’s pasture and his brother’s cultivated fields that may be used as a reference section for this portion of the stream.  In the area were cattle have been fenced out the vegetation is overhanging the bank and the banks are undercut, but not failing. 

This section of stream has also seen an increase in the amount of artificial stream bank stabilization (riprap).  Mr. Gamma said that the high flows of 1996 that were released from Ashley Lake by the Department of Fish Wildlife and Parks took out his bridge and heavily eroded much of the banks.  In response to this increased erosion, Mr. Gamma added rock to portions of the stream.  In rebuilding his bridge it appears he reinforced the bank underneath the bridge, which appears to have caused an increase in the constriction of the creek at this point.  That increased constriction has resulted in eroding and failing banks downstream of the bridge that were not observed in 1987.

Due to the position of this property in the upper end of the Ashley Creek Watershed, I feel this portion of stream is vital in restoring the creek to a more functional state.  My recommendations are to continue to reinventory the sites noted in the 1987 assessment.  Then identify those areas of heavy impact and strategic location.  In cooperation with the landowners adjacent to the creek, develop a plan to reduce the impacts on the creek and create a plan to restore the areas of heavy impact.  As I observed in the field there exist sections of Ashley Creek that can be used as reference reaches in the restoration effort.  Judging by the cooperation and general welcoming attitude and interest that Mr. Gamma showed, a great opportunity exists for a cooperative effort.

Summary of Data

 (Photos are available for highlighted selections)

Map of Study Site

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