turbidity measurements in alameda creek and selected tributaries: august through december 2007...
TRANSCRIPT
Turbidity measurements in Alameda Creek and selected tributaries: August through December
2007
Alicia N. Gilbreath and Lester J. McKee
San Francisco Estuary Institute
Turbidity measurement
Sadar, Hach Co., 2005
Turbidity WQ objective
“Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses.
Increases from normal background light penetration or turbidity relatable to waste discharge shall not be greater than 10 percent in areas where natural turbidity is greater than 50 NTU.”
- San Francisco Regional Water Quality Control Board (SFRWQCB) Basin Plan (2007), Turbidity water quality objective (3.3.19)
Thresholds used in analysis
10 NTU > 50% exposure time 25 NTU > 20% exposure time
and
50 NTU > 10% exposure time
Klein and Trush (in prep), in McBain and Trush, 2007
Aug Sep Oct Nov Dec
Dis
char
ge
(CF
S)
0
100
200
300
400
Results
Ala Ck @ Ardenwood
Ala Ck @ Alvarado
Ala Ck @ Decoto
Ala Ck @ Mission
Ala Ck @ Stonybrook Ck
Ala Ck @ frmr Sunol Dam
Ala Ck @ Sunol Temple
Ala Ck @ 680
Ala Ck @ Welch Ck
ADLL @ Paloma Bridge
ADLL @ Verona
ADLL @ Bernal
ADV @ Valley
ADV @ Bernal
Alamo Canal @ 580
Mocho @ Hopyard
Tsjra @ W. Las Positas
Mocho @ Santa Rita
Line G-3 @ Mocho
Mocho above Line G-3
Mocho @ El Charro
ALP @ El Charro
ALP @ Livermore
ALP @ First St.
ALT @ Redwood
Turbidity (NTU)
0
10
0
20
0
30
0
40
0
80
0
Alameda Ck @ Ardenwood
Alameda Ck @ Alvarado
Alameda Ck @ Decoto
Alameda Ck @ Mission
Alameda Ck @ Stonybrook Ck
Alameda Ck @ frmr Sunol Dam
Alameda Ck @ Sunol Temple
Alameda Ck @ 680
Alameda Ck @ Welch Ck
Arroyo De La Laguna @ Paloma
Arroyo De La Laguna @ Verona
Arroyo De La Laguna @ Bernal
Arroyo Del Valle @ Valley
Arroyo Del Valle @ Bernal
Alamo Canal @ 580
Arroyo Mocho @ Hopyard
Tassajara Ck @ W. Las Positas
Arroyo Mocho @ Santa Rita
Line G-3 @ Arroyo Mocho
Arroyo Mocho above Line G-3
Arroyo Mocho @ El Charro
Arroyo Las Positas @ El Charro
Arroyo Las Positas @ Livermore
Arroyo Las Positas @ First
Altamont Ck near Bristlecone
Turbidity (NTU)
0 10
20
30
40
50
60
Ala Ck @ Ardenwood
Ala Ck @ Alvarado
Ala Ck @ Decoto
Ala Ck @ Mission
Ala Ck @ Stonybrook Ck
Ala Ck @ frmr Sunol Dam
Ala Ck @ Sunol Temple
Ala Ck @ 680
Ala Ck @ Welch Ck
ADLL @ Paloma Bridge
ADLL @ Verona
ADLL @ Bernal
ADV @ Valley
ADV @ Bernal
Alamo Canal @ 580
Mocho @ Hopyard
Tsjra @ W. Las Positas
Mocho @ Santa Rita
Line G-3 @ Mocho
Mocho above Line G-3
Mocho @ El Charro
ALP @ El Charro
ALP @ Livermore
ALP @ First St.
ALT @ Redwood
Turbidity (NTU)
0
10
0
20
0
30
0
40
0
80
0
Alameda Ck @ Ardenwood
Alameda Ck @ Alvarado
Alameda Ck @ Decoto
Alameda Ck @ Mission
Alameda Ck @ Stonybrook Ck
Alameda Ck @ frmr Sunol Dam
Alameda Ck @ Sunol Temple
Alameda Ck @ 680
Alameda Ck @ Welch Ck
Arroyo De La Laguna @ Paloma
Arroyo De La Laguna @ Verona
Arroyo De La Laguna @ Bernal
Arroyo Del Valle @ Valley
Arroyo Del Valle @ Bernal
Alamo Canal @ 580
Arroyo Mocho @ Hopyard
Tassajara Ck @ W. Las Positas
Arroyo Mocho @ Santa Rita
Line G-3 @ Arroyo Mocho
Arroyo Mocho above Line G-3
Arroyo Mocho @ El Charro
Arroyo Las Positas @ El Charro
Arroyo Las Positas @ Livermore
Arroyo Las Positas @ First
Altamont Ck near Bristlecone
Turbidity (NTU)
0 10
20
30
40
50
60
USGS Gage Arroyo De La Laguna at Verona
09/
10/0
7
09/
24/0
7
10/
08/0
7
10/
22/0
7
11/
05/0
7
11/
19/0
7
12/
03/0
7
Tu
rbid
ity (
FN
U)
0
50
100
150250
300
Dis
cha
rge
(C
FS
)
0
50
100
150250
300Turbidity (USGS)Turbidity (SFEI)Discharge
Results compared
to thresholds
Percentage of Sampling Events:
≥ 10 NTU ≥ 25 NTU ≥ 50 NTU Count (n)
Alameda Ck @ Ardenwood 100% 95% 63% 19
Alameda Ck @ Alvarado 39% 0% 0% 18
Alameda Ck @ Decoto 11% 0% 0% 9
Alameda Ck @ Mission 33% 8% 8% 12
Alameda Ck @ Stonybrook Ck 10% 0% 0% 10
Alameda Ck @ frmr Sunol Dam 8% 8% 8% 12
Alameda Ck @ Sunol Temple 20% 0% 0% 5
Alameda Ck @ 680 0% 0% 0% 3
Alameda Ck @ Welch Ck 0% 0% 0% 8
Arroyo De La Laguna @ Paloma 53% 5% 5% 19
Arroyo De La Laguna @ Verona 89% 5% 5% 19
Arroyo De La Laguna @ Bernal 84% 5% 5% 19
Arroyo Del Valle @ Valley 5% 0% 0% 19
Arroyo Del Valle @ Bernal 0% 0% 0% 3
Alamo Canal @ 580 41% 6% 6% 17
Arroyo Mocho @ Hopyard 100% 95% 53% 19
Tassajara Ck @ W. Las Positas 94% 71% 24% 17
Arroyo Mocho @ Santa Rita 100% 71% 29% 17
Line G-3 @ Arroyo Mocho 92% 69% 31% 13
Arroyo Mocho above Line G-3 77% 15% 8% 13
Arroyo Mocho @ El Charro 50% 50% 50% 2
Arroyo Las Positas @ El Charro 21% 5% 5% 19
Arroyo Las Positas @ Livermore 0% 0% 0% 3
Arroyo Las Positas @ First 20% 10% 0% 10
Altamont Ck @ Bristlecone 67% 33% 0% 6
Recommendations
1) Conduct a bioenergetics study in areas where turbidity may impact the fish.
2) Investigate sources and management options for inputs into Arroyo Mocho.