LETTER: I’m a retired design engineer and I can tell you the Boston Barrier is in the wrong place


Mark Simmonds: your records will show that I am a retired design engineer who, for many years until retiring, worked as a consultant in the field of docks and harbours, flood defence, marinas etc.

I contacted you in the past in the hope that you could influence the position of the new tidal flood barrier site.

You made contact with the Environment Agency who politely told you I did not know what I was talking about. In early 2010 the then-consultants on the project (they have since changed) put out a number of proposed sites and invited comment from the public.

I introduced myself saying that in my opinion none of the proposed sites were suitable. I was introduced to the consultant’s representative who requested that I write a report (at no cost to the EA) explaining why the only site that I believed to be suitable would be at the entrance of the Haven from the Wash.

If a tidal barrier were at that place last Thursday, Boston would not have seen any of the floods that it did. Other places have theirs, London in particular, and did not flood.

If the barrier had been placed where the EA intended, prior to last Thursday, Boston would still have been flooded because the water overtopped the Haven retaining walls.

In January 2012 Boston councillors held a meeting with the EA, a representative from the Black Sluice Brainage Board and myself. It appears, based on another exhibition in November 2011, the main reason for the barrier is to retain water for the EA boat link project.

This would not be necessary if the Black Sluice Lock had been designed to allow traffic in both directions at most stages of the tide. It can, in fact, only be used providing the Haven is higher than the 40ft drain.

As the water can only drain from the Black Sluice when the Haven is lower this is a problem. You cannot have both at once.

The solution, proposed by the EA, was to retain the Haven water during the day and release it at night. This is impossible because barriers can only be opened and closed when the water levels are the same on both sides and the tide inconveniently does not follow the same cycle as the sun.

When it was pointed out that for the proposed system to work all the walls downstream of the site would have to be raised, we were told that this would be done but it would take 100 years. So if we do not get another flood for 100 years it will then be alright.

Unlike the EA, I make no claim to having a crystal ball but the meteorologists tell us that when we get high spring tides and low pressure over the Atlantic, the conditions that appertained on Thursday will happen again.

It may not be for 200 years or it could be at the next extra high spring tide. Something needs to done on an urgent basis.

Place the barrier ASAP at the entrance from the Wash to the Haven and, like the Thames barrier, only close it at extra high tides. Boston should then never again see the catastrophe of last Thursday.

David C. J. Matthews

Via email