Flood Risk

bluey1406

Hi, I've searched the forum but struggled to find a lot of recent advice.

We are buying a house and have mortgage offer in place.

The environmental search has flagged that the property is at moderate to high risk of surface water flooding. The property is rural and has a septic tank and is not connected to a public sewer.  The property was built in 1998 and has never flooded before.

I have checked the government website for other properties and post codes in the same road (it's quite a long road) and it seems to be a bit of a lottery as to whether a property is considered to be at high risk of surface water flooding or very low.

I don't think I am massively concerned by this risk; I've got quotes for buildings insurance and the quotes don't seem to suggest that insurers perceive a high risk as the quotes are under £200 for combined buildings and contents. There is a small stream at the bottom of the garden (a ditch really with a bit of water in it) which I've also declared for insurance as it asks the question.

The other issue on the search however is the Climate Index rating which is E.  It says that in the next 5 and 30 years the property is at significant risk of ground instability due to identified risks (from the surface water flooding I presume given that no other risks are identified) that in the worse case scenario could render the house uninhabitable. Slightly more concerning but I guess is built on worse case (and probably never going to happen) scenario.

However, elsewhere in the report it says that no issues are identified with ground stability so somewhat confused.

Are they saying that IF the property/area floods, then this COULD affect ground stability?

I'd be really grateful for any voices of sensible reason on the topic. I don't want to not buy the house but also don't want to buy a turkey that I can't sell in 5 or 10 years time.

Thanks in advance! 🙂

Keep_pedalling

I would not worry about the surface flooding risk. Our house is classed at high risk but other than a totally sodden back garden on occasions the house has had no flooding in the 37 years we have been here. The houses a few doors up are all low risk. 

ProDave

Look at the flood risk MAP not individual properties.  The flood risk is likely to follow contours, and if your house sits on a local high spot it might get flooded all round but not actually in the house.  On the other hand if it is down in a dip, more at risk.

The flood map will show the extent of the likely flooding but it is quite a coarse map.

e.g our house is right on the edge between flood risk and no risk on the map.  What that means in practice is the field behind us which is lower can occasionally flood where it forms a low spot, and in extreme cases a little water may come into our garden at the field boundary.  But that part of the garden is a lot lower than where the house is built so I see no risk.

bluey1406

Thank you for the comments. @ProDave I've looked at the map in the search itself. It shows every property along the road as being in the red high risk zone, but the surrounding areas immediately in front of and behind the properties as being in moderate/low to moderate/low. Given that water travels, I'm very confused as to how it would pass an apparent low risk route into an area assessed as high risk?? Or am I interpreting this incorrectly? 

Trying to attach the plan but struggling...

ProDave

That's the thing with surface water flooding.  It does not necessarily flow.  It could just be a local low spot in the land just fills up with rainwater when it rains faster than it can soak into the ground.  Perhaps the road and all the houses are the bottom of a valley?