For one week each year the tidal Thames is allowed to rise and fall naturally between Richmond and Teddington locks, so that the locks and other infrastructure can be maintained. This gives an opportunity to enjoy rare views of the Thames. Help keep the Thames clear of harmful plastic and other litter. Wear wellingtons or other stout footwear and be prepared for changeable weather. You can just turn up but if you book it will help us organise the event for expected numbers. Meet by the Tide Tables café, Richmond Bridge, TW9 1TH.