1. Huntingdon, Pennsylvania
Study of Oxygen Depletion and Negative Heterograde Formation in Raystown Lake, PA
Sharon Simpson
Juniata College
Huntingdon, Pennsylvania
Advisor - Chuck Yohn

2. Raystown Lake Reservoir created by Raystown Dam
Located in Huntingdon and Bedford Counties
27 miles long, 118 miles of shoreline
8,300 acre surface area

4. Spring Oxygen and Temperature Profile
Lake mixes completely in the spring.
Mixing oxygenates the lower depths of the lake.

5. Typical Oxygen and Temperature Stratification
Lake stratifies in summer
No oxygen inputs to the lower depths of the lake.
Respiration consumes oxygen.
Oxygen profile measures the health of the lake.

6. Typical Oxygen and Temperature Stratification
Epilimnion
Metalimnion
Hypolimnion

7. The Two Issues
Anoxia
Negative heterograde

8. Research Questions What is the extent of the oxygen depletion?
Where are the inputs of the oxygen depleting materials?
What is the extent of the negative heterograde?
Why is the negative heterograde forming?

9. Oxygen Depletion Hypotheses
Input of oxygen demanding materials
From where?
1. Recreational use
2. Sediment sliding
3. Stream input

10. Research Design Where are the low DO values?
Where is the highest rate of depletion?
Sampling sites
5 Main channel sites (sediment sliding)
4 Sites near marinas and campgrounds (recreational sites)
6 Sites in bays of tributaries (stream input sites)
Sampling
Once a week, May to November
Temperature, DO, and % saturation with YSI DO meter
Readings every 1 m until the bottom or 29 m
Data collection completed within 1-3 day time span

11. Sampling Sites

12. July 13, 1998
C1 Raystown Dam Mile 0
I1 Snyder’s Run Mile 2

13. R1 Seven Points Marina Mile 10.5
July 13, 1998
C2 Mile 6
R1 Seven Points Marina Mile 10.5

14. R2 Seven Points Marina Mile 10.7
July 13, 1998
R2 Seven Points Marina Mile 10.7
C3 Mile 13

15. July 13, 1998
I2 James Creek Mile 14
I3 Trough Creek Mile 14.8

16. July 13, 1998
C4 Mile 18
C5 Entriken Bridge Mile 20

17. R4 Lake Raystown Resort Mile 21.5
July 13, 1998
R4 Lake Raystown Resort Mile 21.5
I5 Shy Beaver Creek Mile 21.8

18. July 13, 1998
I6 Juniata River Mile 24

19. r = -0.93, p <0.00

20. Nitrates used as an indicator of nutrient concentrations.
High nutrient concentration causes oxygen depletion.
r = 0.88, p < 0.00

21. Conclusions
The major source of oxygen depleting materials to Raystown Lake is at the input of the Juniata River.
There was no difference in oxygen depletion among the three groups of sites.
The oxygen depletion pattern is not uncommon for reservoirs (Cole 1990).

22. Negative Heterograde Metalimnetic oxygen minimum Possible causes studied
1. Flow pattern of river into reservoir
2. Decomposition of suspended organic matter in the metalimnion

23. Conductivity a marker of inflow depth
High conductivity values indicate depth of river inflow.

24. Expected Seston Values if hypothesis is not true

26. Conclusions
The metalimnetic oxygen minimum is caused by a collection of organic material in the metalimnion.
The presence of a metalimnetic oxygen minimum is not uncommon in reservoirs (Cole 1990).

27. Acknowledgments Raystown Field Station - Chuck Yohn Pfizer Corporation
Emily Sowell, Huntingdon High School
AJ Maurer, Juniata College
Dr. Paula Martin, Env. Sci and Studies Dep. Juniata College
Ken Culp, U.S. Army Corps of Engineers
Dr. I. David Reingold, Chemistry Department, Juniata College
Dr. Elaine Keithan, Biology Department, Bucknell University