Carbaryl, Carbofuran, and Methomyl - National Marine Fisheries ...

concentrations that exceeded EPA guidelines for protecting aquatic life (Bortleson and
Ebbert 2000). Insecticides screened for included both carbofuran and methomyl.
Carbofuran was detected, while methomyl was not. No insecticides were found in
shallow ground water below urban residential land (Bortleson and Ebbert 2000).
Habitat Restoration
Positive changes in water quality in the region are evident. One of the most notable
improvements was the elimination of sewage effluent to Lake Washington in the mid-
1960s. This significantly reduced problems within the lake from phosphorus pollution
and triggered a concomitant reduction in cyanobacteria (Ruckelshaus and McClure
2007). Even so, as the population and industry has risen in the region a number of new
and legacy pollutants are of concern.
Mining
Mining has a long history in Washington. In 2004, the state was ranked 13 th nationally in
total nonfuel mineral production value and 17 th in coal production (Palmisano, Ellis et al.
1993; NMA 2007). Metal mining for all metals (zinc, copper, lead, silver, and gold)
peaked between 1940 and 1970 (Palmisano, Ellis et al. 1993). Today, construction sand
and gravel, Portland cement, and crushed stone are the predominant materials mined.
Where sand and gravel is mined from riverbeds (gravel bars and floodplains) it may
result in changes in channel elevations and patterns, instream sediment loads, and
seriously alter instream habitat. In some cases, instream or floodplain mining has
resulted in large scale river avulsions. The effect of mining in a stream or reach depends
upon the rate of harvest and the natural rate of replenishment, as well as flood and
precipitation conditions during or after the mining operations.
Artificial Propagation
The artificial propagation of late-returning Chinook salmon is widespread throughout
Puget Sound (Good, Waples et al. 2005). Summer/fall Chinook salmon transfers
between watersheds within and outside the region have been commonplace throughout
this century. Therefore, the purity of naturally spawning stocks varies from river to river.
Nearly 2 billion Chinook salmon have been released into Puget Sound tributaries since
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