Free-Flow… when and why??

The Marina water level is constantly dropping due to boats locking in and out and the only way we can maintain the water level is to either Pump the water in at night when the tide is high, which you may have noticed if you have walked passed the marina in the early hours or the other way is to “Free-Flow” Every 2-3 weeks when we have rising spring tides of 12m (Chart Datum) and above, we have the opportunity to open both the inner and outer lock gates and allow the water to Free-Flow into the Marina.

The minimum water level in the Marina we can go down to is 12m (Chart Datum) we also have a maximum of 14m, but we usually stay around 13.3m, the actual depth of water throughout Marina is around 6m.

As we approach possible Free-Flow tidal heights (spring tides) of 12m and above, we allow the Marina level to drop a little to make the best use of the rising spring tides.

As the tides rises to meet the Marina level, we open both sets of gates and let the Marina water naturally rise with the tide. We continue with this until either the tide stops rising or continues to a height of 14m when we will close the gates, even if the tide rises passed this height we can’t let any more than 14m into the Marina.

Depending on the Marina level at the start of free flow and the height of tide it can mean that both set of gates will be open from between 5 and 30mins.

Unfortunately, all tidal heights times are predictions, so depending on wind direction, barometric pressure and many other factors, so we never quite know if the prediction will be reached or surpassed.

We try to cause as little disruption as possible, but it is a necessary part of marina life. 

The Photos show a Free-flow opened at 06:15 at a height of 12.70m and closed at 06:45 at a height of 13.44m 

If you would like to know when we are possible Free-Flowing you can check out Portishead tidal times for any tidal height of 12m and above, which usually occur when the when the high tide is between 07:00-10:30am and 19:00-22:30.