The Lower Kootenai and Moyie watersheds remained in a relatively natural condition until
the early twentieth century when miners, loggers, and ranchers began to settle in the area.
In recent years, timber harvest and grazing have
been restricted to the floodplain of the lower portion of the Kootenai River.
Excessive sediment in the subbasin comes primarily from road crossings and encroachment.
Temperature is most affected by stream shading. Metals and pH exceedances stem from historic mining activity near the headwaters of Blue Joe Creek.
Water temperatures are an issue in the Lower Kootenai and Moyie Subbasins. An SBA and
TMDL for water temperatures was developed in 2005; however, before the temperature
SBA/TMDL was completed, the Kootenai and Moyie River Basin Watershed Advisory
Group suggested it be incorporated into this
TMDL.
An assessment of temperature data in 2002 indicates
that all monitored streams in the Lower Kootenai and Moyie Subbasins exceed Idaho
temperature criteria. In a situation where all streams, including un-disrupted streams, have
numeric criteria exceedances, a special look at natural conditions must be taken into account. The Lower Kootenai and Moyie watersheds are located in the northern-most portion of Idaho
at relatively low elevations. Throughout the state it has been demonstrated that water
temperatures are most strongly affected by air temperatures, which directly relate to elevation.
Metals and pH are identified as pollutants for Blue Joe Creek. At the time of the initial 1998
assessment, Blue Joe Creek was void of aquatic insect life and was impaired. The source of
metals and associated pH issues is the now abandoned Continental Mine. Through
environmental cleanup activities, both DEQ
and the USDA Forest Service have been working to reduce metals and
pH loading over the last three years. All reasonable TMDL implementation activities for metals and pH loading are complete, and Blue Joe Creek is in a state of recovery. Therefore, TMDLs for metals and pH for Blue Joe Creek were not developed.
The 1998 §303(d) list includes the Moyie River, from the Moyie River Dam to its confluence
with the Kootenai River. Excess sediment is the listed pollutant, and based on the 1998
determination, a TMDL would be required. DEQ does not have Beneficial Use
Reconnaissance (BURP) monitoring data on this section of Moyie River, and believes the
sediment listing decision was based on anecdotal understandings and information. DEQ has
evidence that the listing resulted from a single fine sediment deposition event and that the
stream has recovered since that event. DEQ recommends removing the Moyie River from the §303(d) list and therefore did not develop a TMDL for this river.
Blue Joe Creek, Boulder Creek, and Caribou Creek have also been
removed as candidates for sediment TMDL development for the following reasons:
- Draft TMDLs demonstrated that current sediment generating conditions are better
than those showing full support of the beneficial uses.
- The listings were based on 1995 BURP data that are contrary to data collected
more recently.
- Stressor Identification Analysis (EPA 2000) performed by DEQ supports removal
of these three streams as TMDL candidates.
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