The discharge of Black Creek is 769.33 gallons per minute in its upper reaches. By the Hazleton High School, it increases to 2253.6 gallons per minute and by the Hazleton Wastewater Treatment Plant it increases to 5109 gallons per minute. Downstream of the wastewater treatment plant, the discharge is 22787.5 gallons per minute; at the bridge at Tomhicken it is 31227.33 gallons per minute, and at the State Route 3020 bridge it is 31824.17 gallons per minute. Above and below the Gowen Discharge, the creek's discharge is 32659.33 and 46529.5 gallons per minute respectively. Upstream of the State Route 3018 bridge, the discharge is 55684.17 gallons per minute and near the mouth it is 53938.56 gallons per minute.