Flooding in AG

 

Since this page was first added to the website a great deal of work has been done to lessen the likelihood of flooding in the village, and to mitigate the effects of  both rainfall and tidal flood water. As a result, it is worth pointing out that MUCH OF THE CONTENT HERE IS HISTORICAL

Flooding – What happened here.

A page in our photo Gallery –  Flooding in the Parish – illustrates the widespread floods in the valley in 2012 and  2014. They show just how spectacular the flooding was, but thankfully in most cases there was remarkably little damage.  Thanks to all the people who have contributed their photos for this.

Parts of the parish have been affected by flooding several times over the last twenty years, but we have never been so badly hit as we were in 2012 and 14. We are in an unusual situation here with two streams crossing the lower part of the parish – Parson’s Brook and Waterhead stream flow down from different parts of the catchment and on into a tidal stretch of the River Avon.

The nationwide damage in 2014 gave rise to a more positive attitude in central and local government to try to tackle some of the issues, and Aveton Gifford has benefited from this. In 2014 Devon County Council funded two very effective improvements to accommodate the flow of flood water in both of our streams; the culvert under the bridge at Tree Corner was enlarged (the previous culvert was far too small to cope with the quantity of rain after a flash rainstorm); a new parapet replaced the originals at Waterhead bridge, (previously the bridge acted as a dam to prevent the flow of water) with several gaps in the stonework on both sides to allow flood water to flow both below and above the roadway, and carry on down the stream.

Since then similar flash rainstorms have affected both these streams, but now that the “dam” effect at both bridges has been removed the nearby houses have remained dry; householders previously affected all feel sure that these two improvements alone have made a dramatic and positive difference to their flood risk.

The Flood Resilience Community Pathfinder Project.

Aveton Gifford was one of fifteen communities across Devon to benefit from being part of this pilot project;  there would be help and advice for a group of volunteers to set in place our own flood prevention measures in the parish. As a result we set up our own self help flood resilience group including many of the householders who had been affected, representatives from the hall, the school and the pre-school, and other volunteers willing to help.

AG Flood Group – The Aims.

  • To identify the vulnerable areas in the parish.
  • To identify the causes of flooding there on each occasion.
  • To understand what the threats are in terms of weather conditions.
  • To understand what the threats are in terms of safety.
  • To set up a flood alert system of our own – many of the national warning systems are not always relevant here, and we needed something more appropriate and reliable.
  • To put in place preventative measures where possible.
  • To make an action plan so that danger and damage is limited during a flood.
  • and as time went on; To share and gather further information through Flood and Community Resilience Forums to enable our own parish community resilience.

The Flood Resilience Project – grant money

In addition grant money was available to many of the 2014 affected households to install flood doors and other preventative measures. It also provided equipment for use by the Flood Group and volunteers to take preventative action, and in the worst case for clearing up afterwards.

The Flood Resilience Project was set up with householders and residential properties in mind. However because our one community village hall has been so badly affected by flooding in past years, Aveton Gifford was very lucky to be able to benefit from additional grant money to make flood resilience improvements to the hall.

Rain Gauges.

Localised heavy rainfall is often difficult to predict, and in spite of more accurate weather forecasts nowadays, rain does not always follow the expected direction or quantity so flash floods are  difficult to forecast. Many of our floods have been caused after flash storms in the catchment areas of the two streams through the village and Waterhead.

With advice from the Flood Resilience Project and the availability of grant money Aveton Gifford installed two different monitoring systems to see if these could be helpful. A rain gauge installed to forecast prevailing weather  proved after 4 years to have been ineffective, and so has been discontinued. However a very effective second gauge measuring the height of water in Parson’s Brook by Mill Cottage triggers phone alerts to nearby residents when the height of  that stream has risen above the norm, and preparations can be made if necessary. These have proved very helpful, particularly when some of them have happened during the night. However, thankfully, since the culvert has been widened to cope with the flow of flash flood water, the stream has never risen to past flood levels.

Dredging to Parson’s Brook

Dredging and clearing the impacted silt from under the bypass was finally undertaken in October 2015 – a report on the works can be read in the Oct/November 2015 issue of the mAGpie.

Posts around the car park 

Cars have been flooded several times here in the lower part of the hall car park, and during the very high water of 2014 there was a danger of some of them washing into the stream.  Sturdy chestnut posts have been installed around the parking area to prevent this.

Replacement of bridges over the brook in the Rectory Lawns

This is a copy of an article published in the June 2017 edition of the mAGpie;

If you’ve had a walk through Rectory Lawns recently you may have seen some changes. As part of our ongoing flood prevention measures, two new bridges have been put up to replace the older wooden ones crossing Parson’s Brook. Advice from Devon County’s Flood Resilience team has recommended that everything bordering a watercourse must be completely secure so that nothing can wash away to block bridges or culverts and drains, and we do know to our cost that several houses and the hall have flooded on various occasions over the years when the flow of flood water has been obstructed. Even though work on Tree Corner bridge and recent dredging has improved our flood risk in the village, when we had very heavy rainfall on February 1st this year, the stream overtopped the banks and the bridges in the Rectory Lawns, and the bridges themselves  collected a large amount of debris washed down by the storm.  This highlighted something that has been an ongoing concern for some years; flood water has often loosened them, and on occasion even pulled them right out of the ground, and they can then be carried downstream to block the culvert under the road by the Abrahall’s house. (This culvert is one of our Flood Black Spots; anything blocking the flow of the stream acts as a dam and could cause more flooding to the car park and nearby properties, particularly the hall. The posts put up around the lower car park there now prevent cars being washed into the stream, but February’s heavy rainfall showed that this is still a very vulnerable area, and the one thing left to secure was the bridges.)

When the wooden bridges were taken out in May it could be seen that the fixings had already started to rot, so if nothing had been done about them this could easily have happened again. These new galvanised bridges are longer and much higher than the old ones so flash rainwater can flow right underneath without any obstructions, and they are also heavier and much more securely installed to reduce any danger of washing away. Since they have been put in place some modifications have been made to reduce the gradient of the ramps at either end, and to reduce noise from the metal surface. Both bridges will then be finished with a non-slip top coat which will be laid down over the metal walkway to make them safe in all weather conditions. Once all the work is complete they will be almost maintenance free, last considerably longer than the old wooden ones, and make a positive difference in reducing our flood risk to properties. They have been paid for out of money for our flood resilience measures.

new bridge over the stream, installation  new bridge 1 new bridge 2

Emergency Plan

The parish Emergency Plan has been drawn up, and a separate Flood Plan details the actions to be taken before, during and after flooding, using our teams of volunteers and flood wardens (trained as part of the input from the DCC Flood Resilience Project).

Flood information and self-help measures

FACEBOOK – sign up for alert for  flood warnings!

We now use the Aveton Gifford Community Facebook site to give warning of Devon County and Environment Agency flood warnings. We have found this is the quickest way to pass on emergency information and updates.

Anybody can view the Aveton Gifford Community Facebook page without having their own account, but you would need to check it yourself to see if there had been a recent posting. However it is easy to join Facebook to receive these messages directly to your phone or computer without compromising your privacy.

Weather forecasts.

Environment Agency flood alerts for the River Avon are usually given plenty of publicity in time before an emergency. However for up to date information you can call  Floodline,  a telephone information service which will give the latest flood warning information and advice ; tel: 0845 988 1188

Residents can sign up for EA’s Floodline Warnings Direct  – a  free service that provides flood warnings by phone, text or email. You can register online on the EA’s flood page   or by calling Floodline on 0845 988 1188.

It is worth pointing out that these two Floodlines only apply to specific areas – Environment Agency warnings apply to water levels and tides in the RIVER only, NOT in the two streams up the valley.

We have been advised that a Met Office forecast of RED ALERT should mean that everyone should take what preventative measures they can immediately, not wait to see what happens when the storm is upon us – by then it is usually too late, as these floods are on us  with such unexpected speed.

However, although in recent years these conditions have only hit us on RED Met Office alerts, we were fortunate then that it was not on a particularly high tide. As some of our recent high spring tides have shown us, it is worth being much more aware of potential floods when there is a combination of spring tide, onshore south westerly wind, a low pressure forecast but maybe only an AMBER or even a YELLOW alert.

 

Sandbags,  sandbag stores, and the alternatives.

Limited supplies of sandbags are sometimes available at SHDC depots, but only a few per household – not nearly enough for adequate protection, so householders are strongly advised to make your own arrangements. You can get both sand and bags from local builders merchants – but it is worth pointing out that a surprising number need to be used to be effective, and preferably with some heavy duty plastic sheeting  – this pdf gives further information:

Guidance For Use Of Sandbags (399.4 KB)

Some people have found that they can get a better seal around entrances using bricks or breeze blocks with plastic sheeting, either with, or instead of sandbags, but again you will need enough to build the type of “wall” shown in the pdf above. They do also have the advantage that they can be stored and moved more easily, and don’t deteriorate like the sand bags. Sandbags can then be used if you have them to put on the top to give added weight and stability to your “wall”.

There are limited supplies of sandbags kept here for use in emergency. A  shed has been put up by the entrance to the hall car park, and some sandbags will be stored in that. There is also a smaller store for the school. It is unlikely that there will be enough to go round to householders at the last minute when a flood alert is on us, so if you think you may be affected by flood water or rainwater run-off yourself, it would be wise to get in a supply of your own to keep at home. The outer casing of sandbags will perish over time, particularly if they are left in sunlight, so it is suggested that you keep your own bags stored in the dark if possible.

Keeping the culverts free……..

We need to keep any property close to the stream fixed securely, so that it can’t be washed away.  In previous floods one of the wooden bridges across the brook on the Rectory Lawn washed down to block the culvert by the hall, and probably made the flooding in the hall worse.  The 2 wooden bridges here have now been replaced by higher metal ones which are firmly anchored, but if you have anything which might wash away please can you fix it securely or move it out of harm’s way – rubbish bins, garden furniture etc are all things which might wash downstream and obstruct a bridge or a culvert, and could pose a real threat to safety for anyone trying to clear them.

….. and surface water drains.

There is a strong suspicion that many of the problems people have experienced in the last few floods have been caused because our drains don’t drain.  Experience has shown that properties can flood just as badly from run-off as water from overflowing watercourses.  SHDC budget cuts are now so stringent that visits from parish lengthsmen and gully clearance machines are extremely rare, the parish council can no longer rely on either for regular maintenance.  The blocked and impacted drains in the village have all now been cleared – mainly by volunteers, in particular Peter Smith – but will now have to be kept clear.

For smaller blockages  – if you have drains near you that are prone to getting clogged up please help us out and take them on, it’s usually just a case of keeping them twig and leaf free! For more resistant blockages please let Peter Smith or Peter Javes (parish clerk) know asap if any of them are filling up with soil or gravel, or aren’t  managing to take the water away from the road.

There is also a link here to a DCC  web page where you can report a highway fault directly to them, and that includes blocked drains or gullies and flood damage. You need to report each drain individually so that it can be identified properly –  there is an interactive map on the system that you can click on to confirm the place as well, so the post code isn’t essential.

Sewerage spills

In past years flood water caused sewage overflows from the foul sewer manholes, particularly in Jubilee Street after exceptional rain. Residents need to be aware that raw sewage might leak down the road here to the brook.Flood water can also affect one of the sewage systems near the Hive and the Primary School, and on rare occasions in exceptional rain storms sewage has leaked out into water flowing down past these two buildings. There are also occasional sewage spills down Townswell Lane, and by the bottom of the steps up to Icy Park, so please be aware of these too.

Please do feel free to report them yourself (see numbers below) but most importantly please also alert our Parish Clerk [email protected]

Report it to South West Water:  0800 169 1144   (24 hours).

Please also report it to the Environment Agency Hotline: 0800 80 70 60, as any sewerage spill here goes directly into the stream. These reported spills have to be recorded by the EA, and investigated. The investigation may take a few hours or so, but the fact that they are recorded with a dated incident number is extremely helpful in building up a picture of leaks when negotiating with these authorities.

Sewage solutions –  WaterShed Project.

Drainage work by SWW in early 2016 to divert surface water from all the roofs and tarmacked areas in both the school and hall grounds (up  to 25% of the total volume of water entering the sewers during a storm) should now go directly into the stream. Other modifications to the drains included piping the overflowing spring water from the old village well in Townswell Street straight to the stream rather than down to the foul water drains.

Unfortunately these measures did not solve the problem adequately, and at the time of writing, SWW will install a new pipe from the Jubilee St junction down the green to the treatment works.

Parking in the hall car park.

Cars have been damaged or written off in past floods in the hall car park. Whenever there is a RED ALERT for this area, Aveton Gifford Community Facebook flood alerts will be posted, and in addition a WARNING  NOTICE will be displayed on the notice board to the left of the entrance to this car park advising that it may not be wise to use the car park at this time. The water may affect well over half of the parking spaces here, and although this car park is usually full at night there is other parking in the village that could be used instead.

Don’t cross the brook!

Several places in the village may be unsafe in the event of another flood. There is obvious danger from the speed and height of Parson’s Brook when it is in full flow, and all crossings over the stream should be avoided at all costs – and this includes crossing over the water splash on the tidal road by Timbers car park; the force of the water from the stream crossing the road is enough to be seriously dangerous.

The force of storm water down Jubilee Street can also be hazardous, as many of the surface drains in this area are unable to cope with the flow.

The small stream by the entrance to The Hive can become a torrent in flood conditions, as it flows from the valley behind and washes down through school grounds. Representatives from the Primary School, the Hive and the flood group have worked together to resolve some of the problems that make the flood water so hazardous there, but even so we have been advised that parents and teachers need to be aware of the flow of water near The Hive, and in the school grounds.

The Fisherman’s Rest – emergency hub !

If the village should experience another big flood Athenia and Mark have offered the use of the pub as an emergency centre. The flood group will use it as a base for co-ordinating the volunteer work teams in the village and liaising with the police and emergency services where necessary.

 

Useful links

Environment Agency flood page 

This will take you to a lot of information including flood forecasts, and advice about how to prepare for flooding, and during, and then after a flood.

South Hams District Council flood prevention, with advice and  downloads and further links to other agencies.

National Flood Forum has advice on insurance and flood protection.

Waterside properties

If you have a waterside property the Environment Agency’s page for riperian property owners may be of interest.

The EA also publishes a leaflet explaining your rights and responsibilities “Living On the Edge”:

Living On The Edge - Riparian Responsibilities (546.6 KB)

Downloads

Jacobs report into flooding in AG catchment - 2013 (1.8 MB)

This is the report commissioned by DCC into the specific factors which contributed to the flooding in Aveton Gifford village.

Flood Risk Management Team - explanation of their aims and responsibilities. (490.3 KB)

Update on progress from Flood Risk Management Team. (122.8 KB)

 This update gives the background to how Aveton Gifford became a part of the pilot scheme for the Flood Risk Management Team.

The following three reports were published to summarise the various flooding events in 2012.

DCC Report on December 2012 floods (2.5 MB)

DCC Report on November 2012 floods (5.1 MB)

DCC Report on the summer floods of 2012 (5.0 MB)

Contact numbers

Flood group committee members ; Tim Abrahall (01548 559144)

Ros Brousson (01548 550792)

Peter Smith (01548 550272)

Peter Javes (parish clerk);  tel: (01548)  559283

email:      [email protected]