The Jubilee River will not be available to provide protection from flooding of the River Thames to Cookham, Maidenhead,... for several weeks from 9 October 2020 while emergency repairs are carried out by the Environment Agency to Black Potts Weir.
UPDATE 22 NOVEMBER 2020 'Phase 1' of the work is underway and expected to continue into December. Once phase 1 is complete, the Jubilee River will operate at a half to two thirds of its normal capacity (a maximum flow of 100-120 cubic metres per second). Phase 2 of the repairs is expected to begin in January 2021 and go on until about March. This means Cookham and Maidenhead should not expect to have the full benefits of flood water removal via the Jubilee River before April 2021. The Environment Agency is keeping a close eye on long-range flood forecasts, and has implemented temporary changes to how the Thames is operated upstream and downstream. The Parish Council flood committee has asked the EA flood modeling team to visit Cookham, as well as Maidenhead, Windsor and Eton, to ensure alternative flood management measures are appropriate.
If you haven't done so already, it's a good time to signup for early warnings of flooding with the EA Floodline Warnings online or on 0345 988 1188.
EA November 2020 briefing