16 the oxygen sag caused by a cannery reaches a minimum do equal to 3.0 mg/l. upstream from the cannery, the river do is saturated at 10.0 mg/l, and it has no bod of its own. just downstream from the discharge point, the do is still essentially saturated (i. e., consider the initial oxygen deficit to be zero so the downstream deficit is propositional to the initial bod). by what percentage should the bod of the cannery waste be reduced to assume a healthy stream with at least 5.0 mg/l do everywhere?