# Question: a stream flowing with a velocity of 2 mph contains...

###### Question details

A stream flowing with a velocity of 2 mph contains no BOD, but has an oxygen deficit of 6 mg/L. Ten miles downstream this deficit has been reduced to 4 mg/L through adsorption from the atmosphere. The stream conditions are uniform throughout its length. Assuming the rate of aeration is proportional to the deficit, what would be the deficit 35 miles downstream from the original point?

Answer: 1.45 mg/L but please show work!