What lessons should be learned from summer floods?

An inquiry into this summer's severe flooding has been told that it was not possible to accurately predict where most of the floods would strike.

Environment Agency boss Baroness Young told the Environment, Food and Rural Affairs Committee that most of the floods were "surface water" and not river floods - which the agency is better able to predict.

She also said that overall the response had been good and the vast majority of flood warning systems had worked well.

Do you think more could have been done to have prevented it? What issues would you like to see the committee address?

Short term: improve the defences on high-risk rivers, dredge, raise banks, have appropriate drainage systems. Identify all high-risk areas.

Medium Term: Stop building new homes in areas at risk of flood. Make it a law that anybody selling a home in a high-risk area MUST inform the potential buyer.

Long Term: Reduce carbon emissions to decrease the threat of extreme weather created by global warming.

[spadlet]

I heard that the floods in Sheffield (flash floods due to a month's rain falling in 24hrs) were affected by the following factors:

The flood in the city centre occured due to a river busting it's banks. This river had at least 4 other rivers feeding into it before the point where it burst it's banks. The some of the flooded areas alongside the river used to be wasteland but have been built upon in the last 5 or so years. This does raise the possibility that they built on a flood plane, which in times of unusually high rainfall would be expected to flood, reducing problems downstream.

The reservoir where the water had to be allowed to flow along the overspill, flooding alot of homes, messing up their insurance and ruining the house proces, has been (I think 6 inches) over capacity before it began raining. Thus the Environment Agency didn't have any leeway when all of that water turned up.

I agree with delboy. I think one of the most sensible things would be to accept that some areas flood, or may be needed to absorb excess water and stop building on them. All along the valley that the train goes through between Manchester Victoria and Leeds there are playing fields etc next to the canal and river, so that flooding is not a major problem in the villiages.

Paving gardens and drives with paving tha allows water to drain into the soil beneath, rather than tarmac, would also help. This is because it reduces the water that gets diverted into the streets, to flow down the hills and collect at the bottom.

[Wobs]

The rivers didn't burst their banks in the Hull area. It was simply that the rain had no where to go, that the drains were old, and the volume that fell was way too much for it. In fact the amount that fell was unprecedented.

Because Hull is so flat, even if the drains were better, it is unlikely we would have escaped floods, as the water wouldn't have had time to drain away. The aquafa was already unusually high due to last week's rain, and the pumps that we have were overwelmed.

There are streets that flooded that I've never even seen a problem in before. Not even a large puddle. Whole estates that have never had an issue, are now populated with cararvans and skips, as people try to get their homes back.

Flood defences need improving for Hull, as many are on private property, but they didn't actually cause any problems on this occasion.

[forfi]

Originally Posted by Wobs

The rivers didn't burst their banks in the Hull area. It was simply that the rain had no where to go, that the drains were old, and the volume that fell was way too much for it. In fact the amount that fell was unprecedented.

Because Hull is so flat, even if the drains were better, it is unlikely we would have escaped floods, as the water wouldn't have had time to drain away. The aquafa was already unusually high due to last week's rain, and the pumps that we have were overwelmed.

There are streets that flooded that I've never even seen a problem in before. Not even a large puddle. Whole estates that have never had an issue, are now populated with cararvans and skips, as people try to get their homes back.

Flood defences need improving for Hull, as many are on private property, but they didn't actually cause any problems on this occasion.

A few years back I watched a road on the side of a mountain being washed away over the period of a 3 hour rainstorm.We were sat safely in pub and watched as boulders bounced along in the flood and wrecked the road.Unfortunately we were not stranded and the road was just about passable but there were large rocks from the mountain scattered to almost 1/4 mile from where the road leveled out.Such power in that water.As you point out Wobs,sometimes the water just has nowhere to go for a while.

[spadlet]

Do you think that there's any truth in the prediction that rising sea levels will result in Hull becoming an island protected by sea defences? Apparently when the Environment Agency has to make decisions about strengthening sea defences or letting the water have it's way, it tends to focus on popluation density. So Hull would be worth protecting but not the surrounding countryside.

[Wobs]

Good question.

Obviously, I think we need to protect the area , but if and when sea levels rise, the average high tide could require frequent use of higher levels of defence. Our tidal barrier has been used more frequently than when it first was built, but also, the EA has also adopted "controlled retreat" policies, where large tracks of land have been left to the estuary to flood at high tides.

This has meant improvements in the flood management, but ultimately, if levels rise too high we may end up with inter-tidal mud flats that are much bigger than currently. Whether they will surround Hull, I think is unlikely, as surrounding villages close to the Hull boundary will need to be protected. On the West side, this results in a slight rise in land level in the suburbs, so poses less of a risk from the Humber. On the East, we have a flatter geography, and it is only here that the tide has any chance of making any long term advances like you speak of, if left unprotected.

We could end up like Holland, with large sea defences, protecting valuable land. Indeed, with property prices and a feeling of high population density, it may be felt that such schemes may be worthwhile.

If current attitudes are anything to go by, controlled retreat could be the way forward, with us deciding which land is worth saving. IMHO, most of it is

[Wobs]

With recent storm surge, the only flood warning near us was a "Flood Watch". It was for the between Thormungbald and Lords Clough. Lords Clough is on the edge of Hull, where a drain reaches the Humber.

It is this area that I was referring to as being at risk in the long term. It didn't breach as far as I'm aware, but it shows what area is at risk.

[spadlet]

Is it a large area that is at risk? Is the Environment Agency planning to strengthen the defences in that area?

The summer floods should serve as a wake-up call for government, warns the insurance industry.

http://news.bbc.co.uk/1/hi/business/7125057.stm