2006 303(d) List Update Central Valley RB Staff Comments Slide 1

2006 303(d) List Update
Central Valley RB
Staff Comments
Slide 1
Overarching Issue
z Regional Board should be given
first opportunity to interpret its own
objectives
z Interpreting compliance with
objectives has implications for other
programs
Slide 2
Non-native aquatic species
The new pollutants?
Channel catfish
Mosquito fish
RB5 Fisherman w/
largemouth bass
Slide 3
Temperature
z “Natural” temperature can not be altered
unless beneficial uses are not adversely
impacted
z 21oC criterion used cannot be achieved in
most lower elevation streams
z Baseline for fishery pre-dates major hydro
projects
z Upper Sac River example
Slide 4
Temperature
Upper Sac River Example
Sacramento River Above Dunsmuir
Slide 5
Temperature (1999)
75
21 degrees C
Temperature (deg F)
70
65
Mean
Maximum
Minimum
60
55
50
45
5/20/99
6/9/99
6/29/99
7/19/99
8/8/99
8/28/99
9/17/99
10/7/99
10/27/99
Date
Sacramento River Above Dunsmuir
Slide 6
Temperature
Upper Sac River Example
Sacramento River @ Delta – 2 miles Above Shasta
Slide 7
Temperature (1999)
75
21 degrees C
Temperature (deg F)
70
65
60
55
Mean
Maximum
Minimum
50
45
5/20/99
6/9/99
6/29/99
7/19/99
8/8/99
8/28/99
9/17/99
10/7/99
10/27/99
Date
Sacramento River @ Delta
Slide 8
Standards not Attained
z 1 in 3 year allowable exceedance rate
applies to toxic pollutants
z Additive toxicity of pollutants (diazinon /
chlorpyrifos) must be considered
z Weight of evidence suggests continued
listing
Slide 9
Recommendations
z Allow Regional Board opportunity to
interpret its objectives
‹
‹
Do not list exotic species for Delta, Cosumnes
River, and San Joaquin River
Do not list temperature for N.F. Feather River
and Willow Creek
z List Sacramento River, Feather River, and
Morrison Creek for diazinon
Slide 10