Phosphate levels increased by a factor of 5 from the upstream end of the Hobble Creek to the downstream end. The table below shows upstream, middle, and downstream sites and their phosphorus levels:

Theses results are consistent with a mountain stream traveling through a city. Phosphorus is introduced when people fertilize their lawns and farmers fertilize their crops. The water at the downstream site is still and eutrophic while the water upstream flows quickly and is clear. The EPA recommends no more than 0.1mg/L for streams that do not empty into a reservoir and 0.05 mg/L.