Sources of flood information?

[Penners]

Mrs P and I are interested in a house in Norfolk. It's quite close to a river, although - according to the Environment Agency website - it's just outside the marked flood plain.

From a cursory inspection, I can tell you there are no apparent physical indications that the property has been flooded.

However, before we get too enthusiastic about it, I wondered whether anyone could please recommend any other sources of information on flood risk, flood history, etc.

Any suggestions, please?

 

[Flyfisher]

I'm not 100% sure, but I suspect the EA is the main, if not the definitive, body for this sort of information.

I say this for a couple of reasons. Firstly, I've had dealings with the EA regarding enforced river weed cutting on our bit of fishing as part of their remit is to ensure adequate water flows to reduce the risk of flooding. Unfortunately, their contractors for such work can sometimes be rather 'enthusiastic' with their heavy machinery and can quickly turn a productive trout fishery into a lifeless canal, albeit good for maximising drainage. Happily, good sense eventually prevailed and, in conjunction with the "conservation wing" of the EA, a compromise was reached, but not before the "drainage wing" had produced detailed a report of flooding risks in the area and historical records of actual flooding incidents going back to the 1970's. So they certainly have lots of flood-risk information.

Secondly, a near-neighbour last year mentioned a problem he was having with house insurance premium because his current insurer had EA information showing his house to be in a 'flood-risk' area. If the EA is recognised by the insurance industry for flood-risk information then I'd say that's a pretty good endorsement.

 

[Penners]

Thanks, FF.

I'm interested in your mention of "a report of flooding risks in the area and historical records of actual flooding incidents going back to the 1970's". All I've been able to glean from the EA website is their flood map, and its accompanying notes (accessed by clicking on an area of the map).

Where did you find their historical records of past floods?

 

[Schoolmarm]

I would attempt to check if there has been any "estates" built further up river recently or are any planned.

 

[Flyfisher]

Where did you find their historical records of past floods?

I didn't find the records, the EA provided them to support their case that the river needed 'dredging' (well, that's what we called it as part of our case to prevent it - but that's another story). I had a copy of the report at the time but goodness knows where it is now. This was back in the early 90s. Come to think of it, it might have been the NRA (National Rivers Authority) back then although we always dealt with the same actual people even during the various organisational changes that happened around that time.

I can't think of another organisation that would track/control/manage national environmental matters such as flooding - which is not to say there isn't another one, of course.

 

[CHRIS]

It is the EA for sure, I went on a course last year with the boss of the Geospatial department for E Anglia region and he is always out and about your area.

I will try and find out where you can get some help but I would think that having a Survey done with the correct OSTN02 level datums would be a start. You can now establish a Bench mark to +- 10mm any where in the country using survey grade GPS. This is what the EA insist on and not regular leveling from historic benchmarks from churches etc - I had to do a similar exercise in the centre of Oxford to check the flood plain.

You could call the main office in Cambridge and ask to speak to the Land Surveying dept.

 

[Penners]

I will try and find out where you can get some help but I would think that having a Survey done with the correct OSTN02 level datums would be a start. You can now establish a Bench mark to +- 10mm any where in the country using survey grade GPS. This is what the EA insist on and not regular leveling from historic benchmarks from churches etc.

Chris - that's very interesting, thank you. Would having a survey done give me any definitive measure of the likelihood of flooding in any specific area - over and above the information shown on the EA flood map?

 

[CHRIS]

Would having a survey done give me any definitive measure of the likelihood of flooding in any specific area - over and above the information shown on the EA flood map?

I know that the EA maps are very general and some times if you can find out the flood level of the area around your property (Metres above MSL) you can then carry out a localized survey of the land and most importantly your door threshold. This has happened in Linton near Cambridge where 1 property is 300mm higher than the next and did not flood so each house is looked at on its own merits before anything is decided about flood risk.

The ideal thing would be to look at old publications and find if there are any pictures of the area during a flood - you tend to see a lot of these behind bars in local pubs so could be a perfect opportunity to test the local brews - you know the sort of newspaper cut out from 1972 with everyone looking like extras from the Sweeney pushing small boats up the high street.

If the area is in a high risk spot near a major river it would be worth contacting the EA and be a pest until you get some answers

 

[Penners]

Thanks again, Chris. A solution that involves heavy drinking and making a nuisance of myself sounds absolutely tailored for me.

I shall start planning my pub-crawl right away. :wink:

 

[biffvernon]

"definitive measure of the likelihood " is getting close to an oxymoron. Some notable floods have occured just where floods had not been expected, and there are vast areas coloured a deep shade of blue on the risk maps that have nevr been flooded (yet).

Some of the low-lying areas that appear to be a high flood risk are actually not so much at risk because they are so much at risk that preventative measures like dykes with pumping stations stop them flooding making them not at risk. Living in just such a place makes one wonderfully aware of such things.

There's nothing wrong with moving to a flood risk area as long as you are aware of what might happen and you prepare accordingly. Some of the earliest period properties were built on stilts in lakes and marshes.

If you tell me the grid reference or postcode I'll tell you what I think.

 

[Penners]

"definitive measure of the likelihood " is getting close to an oxymoron.

Fair enough!

Thanks for the offer, Biff. I'll PM you.