1. Emily Saad EAS 4480 Oral Presentation 27 April 2010
Estimating Total Phosphorous and Total Suspended Solids in Freshwater Streams from Turbidity Data
Emily Saad
EAS 4480 Oral Presentation
27 April 2010

2. Background Study Site: Data Collection Objective
Little Bear River (Northern Utah)
Drains into Cutler Reservoir
Eutrophic hypoxic due to high phosphorous levels
TMDL established in reservoir’s tributaries
.05 mg/L
Not yet met by Little Bear
Paradise (upper watershed) and Mendon (lower watershed)
Data Collection
High Frequency: In situ sensors
Physical parameters
Water level, temperature, pH, conductivity, DO, turbidity
Some chemical species (recent technology using UV/Vis)
NO3-, NO2-, chlorophyll
Infrequent: Grab Sampling
Short term variability, diurnal trends omitted
TP digested and analyzed in lab
Surrogate Measurements
Objective
In situ turbidity as a surrogate for more accurate estimation of TP concentrations and TSS

3. p< .05
r= .95
p<.05
r= .84
p<.05
r= .95
p< .05
r= .69

4. Model Used to Simulate TP and TSS
-all based on linear regression
-y=a0+a1x1+Z(B0+B1x1)+ei
- the probability plot of the residuals are not normally distributed suggesting that the assumed parametric distribution (normal) in the regression is incorrect
Jones, et al. (2008)

5. Site Chi Square Test F Test (Variances)
SIM
OBS
PAR
Data not normally distributed
Variances are statistically different
PAR
MEN
MEN

6. Bootstrap Analyses: TSS @ PAR TP @ PAR TP @ MEN TSS @ MEN
9.6E-5±1.9E-4
6.1E-5± 3.3E-4
13.8±.11
.027± 7.8E-5
MEN
MEN
-.044±.052
-.12± .03
.13±.004
48.4±1.03

7. Bootstrap Regression:
Simulated vs. Observed

8. Conclusions
-TP and TSS both significantly correlated with turbidity as these sites
-re-evaluate model not assuming normal distributions
Jones, et al. (2008).