Area: 686 km²
Source: between the villages of Whissonsett and Colkirk
Mouth: Joins Yare at Whitlingham
Navigation: The Wensum is navigable by boat up to New Mills in Norwich, though few motor boats make it past Norwich Riverside. Many stretches of the Wensum as high up as Fakenham can be paddled by canoe but care should be taken around mills and the weir at Costessey, there is also a long portage around Pensthorpe Nature Reserve and again at Attlebridge.
The Wensum begins near Whissonsett before being joined by the River Tat at Tatterford. Meandering through Sculthorpe Moor and Fakenham the Wensum then flows around a newly restored meander before passing Pensthorpe Nature Reserve. From Great Ryburgh to North Elmham the river underwent a number of significant restoration phases during an award winning Environment Agency project to improve river function and habitat. Below North Elmham the Wensum is joined by the Blackwater from Dereham. Between Worthing and Lenwade are many sand and gravel pits which have become popular fishing spots. The Reepham Blackwater joins just before the first Marriots way crossing at Lenwade and the river curves round Ringland entering the outskirts of Norwich. The Wensum meets the Tud at Hellesdon Mill and flows through Norwich to meet the River Yare at Whitlingham.
Environment Agency records show that the Wensum catchment is made up of twelve water bodies, of these two are natural, one is artificial and nine are heavily modified. All of the waterbodies meet the Environment Agency 2016 Cycle 2 target for good chemical status. For ecological status or potential one is graded good, ten moderate and one poor.
Initiatives active within the Wensum catchment include the Wensum Demonstration Test Catchment (Wensum Alliance) and the RiverCare volunteer group in Norwich. The River Wensum Strategy Partnership is led by Norwich City Council in partnership with Norfolk County Council, Environment Agency, Broads Authority and the Wensum River Parkway Partnership.