Do I need a licence for my boat?

The control of the River Great Ouse and Nene is under the Environment Agency and they have a tariff of charges for using a boat on the river, see their website for a list of these tariffs https://www.gov.uk/government/organisations/environment-agency. The River Cam is operated by the Cam Conservators and they have a different tariff system for navigation rights http://www.camconservancy.org/. The Middle Level is under the authority of the Middle Level Commissioners http://www.middlelevel.gov.uk/. They make no navigation charge so if you stay exclusively within the Middle Level system you have no fees to pay. If you have a narrow-beam boat and plan to cruise the canal system it might be worth considering a Gold Licence through the Canal and River Trust, https://canalrivertrust.org.uk/, this covers EA controlled waters and the canals. Other regions have their own unique controlling authorities like the Broads Authority. As a minimum most organisations will require an up to date boat safety certificate and minimum third party insurance of £3million prior to accepting a boat on their respective waterway.