WRIA 62 WMP 032305 - Washington State Department of Ecology

March, 2005 -86- 023-1289-003.3040
control releases from Hungry Horse Dam from the winter months to the spring to aid flow
augmentation.
Reservoir operation under VARQ is generally the same as previous operation during big water years.
In lower water years (80%-100% of average), the winter drawdown is reduced. This provides for
higher spring flows that are closer to natural conditions.
The Environmental Assessment for VARQ on Hungry Horse Reservoir was completed in December
2002 (ACOE and BOR, 2002) and Hungry Horse Reservoir began operating under VARQ that year.
An Environmental Impact Statement is expected to be completed in September 2005.
5.2 Total Maximum Daily Load (TMDL) Development and Implementation in Washington
and Idaho
Under Section 303(d) of the Clean Water Act, the States [i.e., Washington Department of Ecology
(Ecology) and Idaho Department of Environmental Quality (IDEQ)] and tribes (Kalispel Tribe) are
required to identify and prioritize waterbodies that do not meet water quality standards. This list,
known as the List of Impaired or Threatened Waterbodies or 303(d) List, was most recently updated
and approved by EPA in WA and ID in 1998. The draft 2002/2004 list is pending EPA approval.
The last public comment period for the listings ended in December 17, 2004.
The US EPA requires the states to set priorities for cleaning up 303(d) listed waters and to establish a
Total Maximum Daily Load (TMDL) for each under the Clean Water Act. A TMDL is the Total
Maximum Daily Load of a pollutant that can be assimilated by a water body while it maintains
compliance with the water quality standards for its beneficial use. A TMDL study entails an analysis
of how much of a pollutant load a waterbody can assimilate without violating water quality standards,
which are based on the beneficial uses (class of uses) assigned to each waterbody.
5.2.1 303(d) Listed Waterbodies in Washington
The primary water quality problems in WRIA 62 are temperature, dissolved oxygen, pH, fecal
coliform bacteria, total dissolved gas, exotic aquatic species, sediment, pathogens, and several
pesticides. Impaired waterbodies in Washington approved by EPA for listing on the 303(d) list are
shown as impaired within the section of a township and range where the sample(s) indicating the
exceedance was taken.
In WRIA 62, as in the rest of Washington State, temperature is the most common impairment of
surface water quality. Dissolved oxygen levels are also listed for several tributaries in WRIA 62.
Dissolved oxygen and temperature are closely related. The capacity of water to dissolve oxygen
decreases with increasing temperature, and salmonids are sensitive to dissolved oxygen levels as well
as temperature. Exotic aquatic species, especially Eurasian watermilfoil (Myriophyllum spicatum) are
on the 303(d) list for the Pend Oreille River. Other 303(d) listed parameters include total dissolved
gas (a result of regional hydropower facilities’ operations) and several organic compounds, mostly
pesticides or their by-products. Skookum Creek is on the 303(d) list for fecal coliform, most
probably due to land use practices. The 1998 and draft 2000 /2004 303(d) listed waterbodies are
illustrated on Figure 4-7 and 4-8.
WRIA 62 WMP 032305