Following an acquisition by the Great Ouse Catchment Board, locks at Barton Mills and Icklingham were rebuilt in the 1960s, but were isolated when the A11 road bridge was lowered soon afterward.

[2] The upper river is an important focus for prehistoric activity, particularly relating to the Neolithic enclosure at Fornham All Saints.

[3] Just above Barton Mills, a side weir connects the river to the start of the Cut-off Channel, a 28-mile (45 km) drain running from there to Denver along the south-eastern edge of the Fens, which was constructed in the 1950s and 1960s.

There is a weir at King's Staunch, after which comes Jude's Ferry, the current head of navigation, where boats at least 60 feet (18 m) in length can be turned.

A magnificent hoard of late Roman silver was discovered at nearby Thistley Green in 1942, and the 34 pieces, which included bowls, spoons, dishes and goblets, were declared to be Treasure trove and are now in the British Museum.

[5] The stretch from Jude's Ferry to Isleham includes several pill-boxes, which were constructed during World War II to defend against invasion.

[6] Above the start of the lock cut is a memorial to the famous Baptist preacher Charles Spurgeon, who was baptised in the river on 3 May 1850.

Remains of a Roman villa and over 6,000 Bronze-Age artefacts, which are now in the Moyse's Hall Museum at Bury St Edmunds, indicate that it has been a centre of occupation since antiquity.

[8] There are a number of pumping stations on the banks of this section, including the Lark Engine, which has been the main outlet for the drainage of the southern part of Burnt Fen since 1842.

[11] The river is managed and maintained by the Environment Agency, from whom boat owners must obtain a licence in order to use the waterway.

[14] By 1700, the upper reaches were again in disrepair, and Henry Ashley obtained powers to improve the river from Worlington to below Mildenhall Mill, and to make it navigable from there to East Gate bridge in Bury St Edmunds.

The Master of the Rolls gave it to Joshua and Joanna Palmer in 1742, but receipts were meagre, at around £267 per year, and the maintenance carried out was barely sufficient.

In 1790, there were plans for a 31-mile (50 km) link from Bury St Edmunds to the River Stour at Mistley, which John Rennie surveyed, but it involved heavy engineering work, including a 2,420-yard (2,210 m) tunnel, and the estimated cost of £75,000 could not be raised.

obtained in 1827, took over control of the lower river, and re-routed it to join the new course of the Great Ouse which had been diverted into a cut to the west of its original route.

He rebuilt most of the locks and staunches in the 1830s, resulting in increased trade in coal and general merchandise which originated from Kings Lynn, but success was short lived, as the Eastern Union Railway opened a line from Ipswich to Bury St Edmunds in 1846, and decline was immediate.

Their prospectus stated that the Eastern Union Railway had been managing the river for seven years, but little changed, as they failed to raise a working capital of £20,000, and by the 1860s, the route above Mildenhall was ruined.

Like most rivers in the UK, the chemical status changed from good to fail in 2019, due to the presence of polybrominated diphenyl ethers (PBDE) and perfluorooctane sulphonate (PFOS), neither of which had previously been included in the assessment.