The effects of variation of stream velocity, distance, ultimatebiological oxygen demand BOD, on initial dissolved oxygen DO andoptimum dissolved oxygen DO deficit, in Amadi creek was studied..Amadi creek, located in Port‐ Harcourt metropolis is a unique creekthat is of high economic importance to the residents ofRumuobiakani, Mini‐Ewa, Oginigba, Woji and Okujagu communitiesas it hosts the activities of the majority of the companies around theTrans‐ Amadi Industrial area and also provides water for fishing andwater transportation The study was carried out to evaluate the waterquality changes resulting from increasing human and industrialactivities in and around the creek. A point‐source waste waterdischarge with flow rate(Q), biological oxygen demand(BOD), anddissolved oxygen demand (DO), of 0.000018m3/s, 1000 mg/l, and4.1mg/l formed the first case. The other case contained an additionalpoint source with flow rate(Q), biological oxygen demand(BOD), anddissolved oxygen demand(DO) of 0.00003 m3/s, 500mg/l, and 4mg/lrespectively. The study of the DO resources of the stream wasundertaken with the aim of providing concepts which can be ofassistance to regulatory agencies responsi le for making decisions forwater quality management. The DO deficit equations are solved bythe methods of simple calculus (classical optimization), whichsimplifies the mathematical solution of the model equations byavoiding difficult to evaluate integrals. Two scenarios were identifiedand used to investigate the effect of BOD on the DO level in thestream, using mathematical simulation techniques. Simulation resultsof the two scenarios suggest that the dissolved oxygen DO deficit isdepends mainly on the distance between waste discharge pointsHence to ensure minimum impact on water quality waste dischargelocations should be placed at the optimal locations of 10015.382mand 6992.282m upstream and downstream waste discharge pointsrespectively, at an optimum DO deficit of 4.135 mg/l for the firstscenario, and at 41233.43m, 40995.17m, 33605.69m upstream anddownstream waste discharge points respectively for the secondscenario at an optimum DO deficit of 4.567mg/l. A characteristc DOcurve shows the DO deficit increasing as the BOD in the waste wateris being degraded,while the DO deficit decreases as the BODconsumption rate becomes smaller than the reaeration rate, as thewaste stream flows downstream .Generally as stream velocityincreases, the reaeration coefficient increases, resulting in anincreased rate of oxygen transfer between water and theatmosphere, and hence an increase in the DO deficit initially,followed by a gradual decrease further downstream..The ultimateBOD deceases progressively as the waste stream moves downstream.It is recommended that if a new waste input is proposed for a streamboth its BOD input and the proposed location with respect to theother functional parameters are important in order to determine theeffects on the creeks dissolved oxygen DO level.