Purchasing a house located in a very low risk area but surrounded by Flood Zone 2/3

[Chris344]

After a long time searching for a new home, we have found a house that ticks all of the boxes. However, following on from our initial research, the house is in a very low risk Flood Zone but surrounded by Flood Zone 2 and 3 due to the local river. The surface water is also low risk. It looks like the high-risk areas are undeveloped fields.

The house is 4 years old and the planning application indicates that the site water management has been built for 100 years + 30% protection. We spoke to a couple of locals who said they do get the flood warnings but don't get actual flooding, however, we are concerned as typically, parts of Tonbridge are prone to flooding.

Any advice please? Here are a couple of screen shots:

 

[Haggisman]

After a long time searching for a new home, we have found a house that ticks all of the boxes. However, following on from our initial research, the house is in a very low risk Flood Zone but surrounded by Flood Zone 2 and 3 due to the local river. The surface water is also low risk. It looks like the high-risk areas are undeveloped fields.

The house is 4 years old and the planning application indicates that the site water management has been built for 100 years + 30% protection. We spoke to a couple of locals who said they do get the flood warnings but don't get actual flooding, however, we are concerned as typically, parts of Tonbridge are prone to flooding.

Any advice please? Here are a couple of screen shots:

Check if your mortgage provider is happy with it.
Do some insurance quotes and see if they come back as stupid money.
Decide for yourselves if you're happy with the risks of
a) Becoming flooded.
b) Becoming uninsurable.
c) Your house becoming almost worthless.

Not sure what other advice anyone else can give.

If the house was on top of a hill then it would be an easier decision, but looking at street view, it doesn't look particularly higher than the surrounding area...

 

[sigma]

Didn't one guy recently install a home flood defence, is that an option?

 

[jpaul]

The house is 4 years old and the planning application indicates that the site water management has been built for 100 years + 30% protection. We spoke to a couple of locals who said they do get the flood warnings but don't get actual flooding, however, we are concerned as typically, parts of Tonbridge are prone to flooding.

what is the nature of the site water management and it's robustness .. does the planning app reveal that ? additional drainage channels ?

 

[mickyflinn]

Ask them did they get flood insurance what's the premium, which insurer did they choose and why ?

 

[Chris344]

Check if your mortgage provider is happy with it.
Do some insurance quotes and see if they come back as stupid money.
Decide for yourselves if you're happy with the risks of
a) Becoming flooded.
b) Becoming uninsurable.
c) Your house becoming almost worthless.

Not sure what other advice anyone else can give.

If the house was on top of a hill then it would be an easier decision, but looking at street view, it doesn't look particularly higher than the surrounding area...

Thank you, I'll run some insurance quotes.

Apparently, the fields are flood plains and the area has never flooded. The concern is with climate change getting worse, could this close the gap. The land is flat and rises as you head towards Linton, further up.

Edit, insurance is double what we pay now at around £1000.

 

[Chris344]

what is the nature of the site water management and it's robustness .. does the planning app reveal that ? additional drainage channels ?

From the report:

Existing Surface Water Drainage Patterns
The River Beult runs southeast to northwest. The site lies on top of locally raised ground and drains to the River Beult.
Topographical Survey - A detailed topographical survey has been carried out. The site slopes from a high point in the east of 20mAOD (Above Ordnance Datum), west to a level of 18.0mAOD,

The broad strategy is to use a management train of suitable SUDS elements to dispose of surface water runoff from smaller rainfall events through evapotranspiration and infiltration and to attenuate flows from larger events with overflows being conveyed to the public sewer at a rate less than from the existing site. This Surface Water Management Strategy demonstrates that there is sufficient storage on site to attenuate the discharge from the developed site to the public sewer to 1.7 l/s under the 1 year rainfall event and 5.0 l/s under the 100 year plus climate change rainfall event.

This Surface Water Management Strategy provides a treatment train of SUDS components including permeable paving and ponds allowing runoff from all areas of the development to receive the level of treatment recommended within the SUDS Manual. This Surface Water Management Strategy demonstrates that it is possible to reduce flood risk due to surface water runoff from the proposed development to a lower level than the current site presents. This is because attenuation limits runoff from impermeable areas to rates equivalent to runoff from the existing site for the 1 year storm and to less than runoff from the existing site for the 1 in 100 year plus climate change rainfall event.

Given the above the proposals are considered to be acceptable from a surface water drainage perspective with the detailed design being subject to a planning condition.

 

[Peerzy]

Edit, insurance is double what we pay now at around £1000.

I know a lot of buyers would be massively put off by that in the future. It could seriously impact the resale value.

 

[Chris344]

I know a lot of buyers would be massively put off by that in the future. It could seriously impact the resale value.

Our renewal, due in a few weeks, is £450. So more than double, really.

 

[Peerzy]

Our renewal, due in a few weeks, is £450. So more than double, really.

Both seem high, our home insurance last year was about £180 and that's probably all most people expect to pay. £1000 a year with the potential to rise and be impacted by flooding would put enough people off to make it harder to sell / lower the value in my opinion.

 

[200sols]

Wait till they develop those fields, then this house will flood. Insurance will be an issue going forward, probably. Will put some off anyway.

 

[HungryHippos]

I wouldn't risk it, it's not even the high cost of insurance alone that is the issue, but if flooding there gets worse, you'll find no one will insure it, and you will have a worthless house.

 

[adidan]

I wouldn't risk it, it's not even the high cost of insurance alone that is the issue, but if flooding there gets worse, you'll find no one will insure it, and you will have a worthless house.

Was just going to post the exact same.

There are places where this has already happened in the UK

 

[sovietspybob]

I pay about £150 house insurance, if i was looking and the bill was £1000+ that'd be an instant no from me.

As you've said with climate change and the potential for the flood plane fields being developed the risk is only going to get worse over time so it's surely only a matter of time until its uninsurable which will mean the value will take a massive hit and also put most people off.

 

[964rs]

I don't think you can compare your insurance prices with his unless you know the exact details of that particular house.

Size, location and even construction will have a massive effect on price and it could even be he is with an expensive company.

 

[jaybee]

I wonder why the house is up for sale.

 

[Jimbeam3678]

Just walk away, it’s a huge purchase, why take the risk.

 

[jpaul]

Topographical Survey - A detailed topographical survey has been carried out. The site slopes from a high point in the east of 20mAOD (Above Ordnance Datum), west to a level of 18.0mAOD,

sounds a reasonable height (fens I'm about 22m within 1km of 0m and a zone 3) eg. https://en-gb.topographic-map.com/map-kb57/England/?center=52.21312,0.12875&zoom=11

Have you cross-checked insurance costs ..or is there, as suggested, something expensive about the build ?

e: so when york flooded river was 'only' 5m above normal level and this house is 20 ! https://yorkcivictrust.co.uk/heritage/civic-trust-plaques/flood-heights-on-the-ouse/

 

[Chris344]

Thanks all. On balance, it is probably best to walk away. I am not comfortable with the level of risk involved, especially the potential de-valuation.

The house is for sale due to needing to be closer to elderly parents.

 

[RogB]

It looks like in a flood, even if your prospective house was dry you couldn't reach it or leave it. Is that acceptable? Enough shops, pubs and friends in the island to last a week or two?