This will be a good opportunity to clear up directly with the Environment Agency staff a misconception which I believe has grown about the barrier. I notice that a lot of the critical arguments against the Environment Agency shrub clearance work along the Colne tidal defences, particularly upstream of the barrier, rests upon the belief that the barrier should negate the need for such maintenance.

A contact of mine, who works in water engineering, was asked about the Wivenhoe barrier and made this general point:- 

"Although the barrier itself is the main defence, tidal barriers alone are rarely used to protect floodplain in these sorts of situations. For example, although the Thames barrier controls river levels in the Thames through London, the defensive embankments along the river through the city are a critical component of the complete scheme and have to be maintained at required levels and condition, by law."

The need to continue maintenance work on the tidal defences, in spite of the barrier, was confirmed this week by the project manager for the EA work being carried out at the Hythe Marshes. I've posted this elsewhere but here is the relevant bit again:-

"The Barrier at Wivenhoe does not remove the need for this defence as the land is lower than the barrier closure level. It protects the railway line, boundary road, properties between B&Q and the A133 Clingoe Hill and the new science park from tidal flooding. The grass cutting we are currently doing along that defence is something we have always done on a yearly basis, however due to some access issues it was missed occasionally in the last 10 years which is what led to the growth of scrub in some locations."

The Colne Barrier's purpose is simply to act against surge tides.  There is a good Evening Gazette article on it here:
http://www.gazette-news.co.uk/news/local/colchester/8902635.How_barrier_helps_protect_thousands/

That's as much as I know - so time to get along to the barrier on the 17th Sept to find out some more!

I think that this open day will prove to be very useful for those purchasing one of the last 30 properties from Taylor Wimpey and which lie on the site adjacent to the barrier whether this piece of land is regarded as flood plain.

It was interesting to see a photograph relevant to all this in John Stewart's excellent Wivenhoe Memories exhibition at the William Loveless Hall today. It showed the view from Anglesea Road railway bridge, with the Clacton railway line heading off into the distance as it does today and branching off from it was the railway line going to Brightlingsea. But what was most noticeable was the flood plain area covered in water.
The exhibition continues tomorrow (29th Aug) 11 am- 6pm.

A bit more about building houses on flood plains.

Building on land that is designated as flood plain is becoming more and more common. And house insurers are understandably worried
http://news.bbc.co.uk/1/hi/uk/7244013.stm

BUT there are different categories of flood plain.

If an area is considered "Functional Floodplain" there are considerable restrictions on what can be built there. If anyone wants to go into it in detail it is worth looking at the Mid Essex Strategic Flood Risk Assessment - Main Report - Published Oct 2007.

There it explains that..."Functional floodplains have the highest probability of flooding of all the Flood Zones...there are only two appropriate land uses that should be permitted in this zone - water compatible land uses and essential infrastructure."

It adds:-

"The tidal areas of the majority of the Mid Essex area are defended to a high standard. As a result, there are limited functional floodplains in these areas"

Building houses on flood plains is fine as long as you know the slight possible risk of flooding,

Information for anyone thinking of buying one of the new houses currently being built on the Cook's Shipyard development nearest to the Sailing Club and opposite the Colne Barrier. You can now access interactive flood maps from the Environment Agency, and by clicking on the area of interest it will give you details on what level of flood risk you can expect.
Below is the map for the Wivenhoe area. By clicking on the area where the latest phase of building is going on gave information that the EA provide to the insurance industry. As you will see the likelihood of flooding is considered to be "low" but is not immune from flooding despite the tidal defences currently in place.

I really must give my appreciation to Maggie and Bellevue and the Wivenhoe Forum. I have been working full time, picking my kids up from family, phoning agencies etc. and have not had the time to do this level of research. I am now able to make a more informed decision on my purchase. My pull to Wivenhoe has always been,along with the setting, the type of community I wanted to live in and this has only furthered my cause!

Ha, should have added power to the people - well for the meantime!

Thanks for that Sami. As you say-power to the people! And yes, this is a great community. I've lived here since 1976 when I started at the Uni and although I had a brief sojourn in Colchester, I've never really wanted to live anywhere else.
This morning we've again got uncovered lorries carrying what I presume is more 'contaminated' soil from the development.
Yesterday we got TW to put a site operative on Bowes Road to stop lorries coming through before 8am. It's as if we make headway on one front only to be stymied by yet another breach of their 'corporate responsibilities'
Keep on keeping on!