An inclined plate coupled membrane bioreactor for treating feed water having excessive level of nutrients in particular chemical oxygen demand and total nitrogen and suspended solids has an aerobic bioreactor for nitrification and aerobic biodegradation in which membranes are submerged for permeate extraction, and an anoxic bioreactor for denitrification within which the inclined plates are outfitted to confine as much anoxic sludge as possible. An air oxygenating and an air scouring are continuously provided to the aerobic bioreactor to maintain a desired aerobic environment and to mitigate membrane fouling while an intermittent air blowing is provided to the anoxic bioreactor to blow out gaseous content generated through denitrification and to rectify the uniformed flow along the inclined plates. The aerobic sludge is recycled to the lower compartment of anoxic bioreactor and the supernatant of anoxic bioreactor is collected as weir effluent and delivered to the downstream aerobic bioreactor. Permeate is intermittently extracted from the membranes by a suction pump. There is no excess sludge withdrawn from the inclined plate coupled membrane bioreactor throughout the experiment.