Pond Run Tributaries (See Graphs and Tables)

Nutrient testing along the two Pond Run tributaries revealed relatively low concentrations of nitrate-nitrogen (< 0.3 ppm) and total phosphorus (< 0.02 ppm) in the smaller southern stream reaches (site #’s 1 and 3) and rather high concentrations of nitrate-nitrogen (0.4-3.5 ppm) and phosphorus (0.04 - 0.11 ppm) in the larger northern stream reaches (site #’s 4-8). All values (except site # 7’s 0.11 ppm result) are well within FW-2 maximum standards of 10 ppm nitrate-nitrogen and 0.1 ppm phosphates. Although both watercourses are largely surrounded by residences and farmland, the northern tributary is close to the commercial strip’s run-off. The unusually high reading of 3.5 ppm (site #5) was confirmed by re-testing. Water for this sample was collected below a concrete slab that may receive groundwater locally contaminated by septic tank overflow or run off from fertilized areas.

Concerning heavy metal concentrations

With respect to physical conditions, the turbidity of the southern Pond Run tributary increased going downstream (3 to 23 FAU), but the northern one’s turbidity decreased somewhat going downstream (23 to 14 FAU). All readings were relatively low. South branch temperatures tended to be somewhat higher (about 29 degrees C) than north branch values (about 21 – 25 degrees C). The south branch had shallower water and tended to have generally less tree canopy than did the north branch, so shade cooling is probably a factor in the difference found. Northern tributary pH readings (6.37 – 7.31) were much lower than southern ones (about 9.25). It may be that the extra organic matter to be decomposed, falling from the north branch’s more extensive canopy, coupled with lower photosynthesis due to greater shade, pushes pH values lower compared to the more open waters of the south branch. DO concentrations for both branches were in the range 7.5 – 10.2 ppm, though the southern tributary’s higher DO readings may benefit again from greater photosynthesis under an open sky compared to the more shaded northern tributary’s lower DO readings. In any case, both Upper Pond Run branches meet both relevant FW-2 physical condition standards of 30 degrees maximum temperature and 5 ppm minimum DO.

Results and Discussion (continue to second part)

Introduction

Experimental Procedure

Summary and Conclusions

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