The River Meon rises one mile (1.6 km) south of the village centre of East Meon. It flows due north, then northwest to West Meon, and southwest to Warnford followed by its characteristic, quite straight, south-southwest course, with many tiny wobbles in short stretches. The river descends through the villages of Exton, Corhampton and Meonstoke, Droxford, Wickham, and Titchfield. The river outflows over 2 miles (3.2 km) of estuary through the marshes of the Titchfield Haven National Nature Reserve to enter the Solent through a small harbour at Hill Head.[2] Overall the valley forms the shape of that of a shepherd's crook.
The Environment Agency measures the water quality of the river systems in England. Each is given an overall ecological status, which may be one of five levels: high, good, moderate, poor and bad. There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of invertebrates, angiosperms and fish. Chemical status, which compares the concentrations of various chemicals against known safe concentrations, is rated good or fail.[3]