The PLA's Ebb Tide Fluvial Flow Flag Warning system (above) is very similar to the Environment Agencys well established River Conditions system. That system, in place upriver above Teddington Lock, indicates the water conditions between locks using red, yellow and green boards (positioned on the locks). It has long been agreed upriver that: if yellow boards are showing, rowing activity is limited to only the more experienced crews and; that if red boards are showing then, in the interested of safety, no rowing should take place
The system updates automatically twice a day: at 06.00 and 18.00 hrs
The Tideway is larger and therefore better able to cope with increased water volume but a faster stream makes for more difficult navigation conditions. The PLA's system is only for the Tideway (below Teddington Lock) and also applies only on the Ebb Tide.
Very low or high flow conditions can mean that the tidal predictions may no longer be accurate, especially if the Thames Barrier is shut. Like at the change of the tide, if in doubt about the direction of flow, position yourself on the starboard side of the channel. Please contact either the Safety Advisor or the captain if you have any questions or require further advice.
BLACK FLAG Lower than average Fluvial Flow
No restrictions but extra caution should be taken at low tide due to shallower than usual foreshore.
GREEN FLAG Normal Fluvial Flow
Keep a good lookout and navigate according to the Tideway Code and Cygnet Approved Steers Policy
YELLOW FLAG Caution, strong Fluvial Flow
Organised crew boats will be at the discretion of the captaincy/coaches/coxes/steers
Inexperienced crews should not boat on the ebb tide
Strongly advise experienced crews, small boats and privateers not to boat on the ebb tide
Preferably adjust outing times to boat on the flood tide
If conditions are considered to be rowable, do not go above UL or below Barn Elms
Carry a phone, sign-out and make sure that somebody knows you have gone afloat
Strictly no rowing in the dark on a yellow flag
RED FLAG Extreme Caution, very strong Fluvial Flow
Strictly no outings on the ebb tide, including experienced crews and privateers
Adjust outing times to boat on the low flood tide only
Very serious consideration given to boating on the flood tide, especially small boats and coxless boats
If you must boat on the flood tide, experienced crews only
Do not to go above UL or below Barn Elms
Carry a phone, sign out and make sure that somebody knows you have gone afloat
Strictly no rowing in the dark on a red flag
