Below a discharge from a wasterwater treament plant , an 8.6km stream has a reoxygenation constant of .4 d^-1, a velocity of .15m/s, a dissolved oxygen concentration of 6mg/L, and an ultimate demand of 25mg/L. The stream is 15C, the deoxygenation constant is estimated at .25d^-1. What will be the impact on fish population in the stream