The hydraulic forces in the river tides are very severe and the 19^th Century river wall structure deteriorates quickly once the river gets into the mortar jointing the granite and Kentish Ragstone walling blocks. The main river wall either side of River Gate fronting the Old Royal Naval College was significantly repaired in the early 2000’s, but ‘The Knuckle’ walling at the eastern end was subsequently deteriorating and was repaired by Greenwich Foundation’s term contractor. The wall was scaffolded but the working decks had to be extremely well tied-down to resist the force of water, and the survey work, then deep-packing, pointing and stone indents had to be carried out at speed between tides which come in surprisingly quickly. Special mortars were used to take a first-set between tides sufficient to resist water forces. The works required a series of statutory consents from the Crown Estate, Port of London Authority, Environment Agency and others. Measures are being considered for river wall protection and repairs at the eastern extremity of the river wall boundary to the Old Royal Naval College and Bellot Gardens.