Nothing bore-ing about the Severn Estuary

Big tides go in cycles depending on the alignment of the moon and earth, and, to a lesser extent, all the other planets in the solar system. If you want the detail have a look here https://metofficenews.wordpress.com/2015/02/20/super-tides-the-weather-and-coastal-flood-risk/

The cycle is about 18 years and February 2015 saw some of the biggest tides in that cycle. This is big news on the Severn Estuary where the tidal range (the difference in water levels between high and low tide) is huge – up to 15 metres at Avonmouth.

The Severn Estuary is like a huge funnel. Tidal sea water pushes up the Bristol Channel and gets increasingly contrained by the narrowing channel, raising levels dramatically. The bigger the tide, the greater the rise.

The most spectacular result of high tides on the estuary is the world famous Severn Bore.  Large tidal bores (which is what the Severn bore is) are actually very unusual and only happen at a handful of locations across the world where there is a large tidal range. The Severn Estuary has the third largest tidal range in the world (behind the Bay of Fundy in North America and Ungava Bay in Canada).

Bores happen when the front edge of the advancing tide becomes contrained by the sides of the estuary, forcing the water up into a wave. It is pushed along by the millions of tonnes of water in the advancing tide behind.

The Severn Bore can usually be seen between Sharpness and Maisemore Weir in Gloucester, a distance of around 20 miles. It travels at a speed of 8-13 miles an hour.

The height of the wave can be anything from a few inches to over six feet. This is largely dependent on the size of the tide but is also influenced by wind, weather systems over the Atlantic and the amount of fresh water coming down the river. Bore forecasts are available well in advance and give them a star rating, the the best (biggest) being five star bores. You can find the forecasts here: http://www.thesevernbore.co.uk/timetable/4586702434

Watching the bore is a great experience. It makes an amazing rumbling sound which you can hear well before you see the wave. The wave itself and the boiling, tumultuous water pushing it seem completely alien on an estuary that is usually fairly calm and placid.

Not surprisingly the spectacle attracts thousands of sightseers and also large numbers of surfers who travel great distances to ride the wave (with varying degrees of success!). Keen surfers try to catch the wave three times during a single pass (usually at Newnham, then Minsterworth and finally Gloucester).

At the Environment Agency we’re more interested in the hour after the bore has passed. This is the time when water levels rise dramatically and very quickly. The rise can be 15 metres at Avonmouth, 10 metres at Sharpness and 6 metres at Minsterworth. This rise is just as spectacular as the bore itself, although the majority of bore watchers do not stay to see it.The impact of the tide is felt much higher up the river than Gloucester. Amazingly, during the February high tides the river at Upton in Worcestershire (about 60 miles from the estuary) was pushed into reverse twice a day. The graph below shows how normal flows of about 100 tonnes of water per second travelling downstream changed to an upstream flow of up to 40 tonnes per second in a matter of minutes. There was also an accompanying rapid rise in water levels of over half a metre. Incredible!

We have miles of flood defences along the length of the Severn Estuary which protect over a thousand homes and businesses. Few people notice most of them as they look like natural grass banks. However, if they weren’t there high tides would routinely cause extensive flooding across the estuary. When high tides are imminent we check all our defences to ensure they are in good working order. This is no small task given the extent of the defences and the remote nature of parts of the estuary.

After the high tides and storms of 2014 some of our defences were damaged. We spent the autumn and early winter carrying out Over £3 million of repairs so they would be ready for the huge tides of 2015. In February they received a good test (like Minsterworth here) and performed perfectly.

There are more very big tides in 2015 (especially in March and September). We’re ready for them.

Why not get out yourself and experience a truly world class natural phenomenon.

Video courtesy @theocair 

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A year I won’t forget! My 2014

January and February

A conveyor belt of storms, pushed along by a supercharged jetstream, led to prolonged and widespread flooding across much of England during the first two months of 2014.

Our incident room in Tewkesbury was open 24/7 for 63 days between Christmas 2013 and the beginning of March. Across the Severn and Wye catchments hundreds of flood warnings were issued, barriers went up and down, river blockages were removed, reappeared and removed again. Our 250 local staff were pushed to the limits. I’ve seen bigger floods but never one as long lasting!
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As 2014 started our immediate concerns were high tides and surges in the Severn Estuary rather than conventional river flooding. Storm systems barrelling in off the Atlantic were pushing water up the funnel of the Estuary and this was coinciding with very high tides. Our flood defences protected thousands of homes along the Estuary but in a few locations the water was so high it came over the top, causing flooding behind.

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The power and speed of this type of flooding is awesome. Water levels rise very quickly and once water comes over the top of flood banks it travels a long way very fast!

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I spent several days around Minsterworth just below Gloucester servicing the demands of a voracious media pack which took up residence around the appropriately-named Severn Bore pub (which was flooded).
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The tides receded soon after New Year but there was no time to relax as river levels were rising rapidly on the Severn upstream of Gloucester as a result of prolonged heavy rainfall. Our flood barriers started going up at Bewdley and Shrewsbury and flood warnings became more frequent and widespread as the rain kept coming.

A brief respite towards the end of January was swiftly followed by more high tides coinciding with surges at the start of February resulting in more flooding a disruption along the Severn and Wye Estuaries. We were growing increasingly concerned about the cumulative effects of high water and wave action on our flood defences on the Severn Estuary and a lot of time was taken making sure that they remained effective.

Flooding reached its peak around the middle of February. The cumulative effects of two months of exceptional rainfall across the south of England. On our patch the biggest problems were on the River Severn from Bewdley to Tewkesbury where levels were the highest seen for over ten years in many locations.

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Other communities were also badly affected, including Callow End and East Waterside in Upton. In Worcester many homes in the Diglis area were also flooded. Spending time with flooded home and business owners is a sobering experience and probably the thing that drives me most to do whatever I can to help.

However, the local situation would have been much, much worse if it hadn’t been for our flood defences; most of which had been build since the huge floods of 2007.
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Upton, Pershore, Kempsey, Powick, Bewdley and parts of Gloucester and Worcester would all have been flooded at the levels we experienced.

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Over 500 homes and businesses in Worcestershire alone stayed dry because of our defences and the hard work of our folk who made sure they were in place and working properly.

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For a few days in mid February, Worcester became the centre of national media attention as water levels neared those of 2007. In addition to the flooding to some homes and businesses the transport network was seriously affected, causing gridlock and concerns for the town’s economy.

A huge operation involving all the responding organisations (police, fire, ambulance, councils, volunteers and even the army) swung into action to manage the situation and minimise the impacts. I was proud to be part of that response. It wasn’t perfect but I honestly believe it made a real difference.

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I spent two weeks on and around Worcester Bridge, juggling media interviews, Silver Command meetings and simply being the face of the Environment Agency.

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Without doubt the most surprising and bizarre occurrence of the two months was the public reaction to my media appearances and social media ramblings. It may surprise you that signing autographs and posing for photos is not part of a normal Environment Agency working day!

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By the end of February the worst of the flooding was over, although we had one more set of high tides and surges on the Severn Estuary to contend with. It had been a bonkers two months that had stretched us to the limits. Many of our people had been working solidly in all weathers, in 24/7 shifts since before Christmas. We were knackered!

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Fortunately, flooding did not return and it wasn’t until the very end of the year that river levels began to rise again.

March

The waters may have been receding but much of March was spent dealing with the aftermath of the floods.

Months of high river levels and big flows resulted in debris building up against many bridges and structures. We need to remove these, both to prevent damage to the structures and to reduce the risk of flooding when the waters rise again. They are often also very unsightly and attract many complaints!

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Probably the most high profile of these debris build-ups happens against Worcester Bridge. In early March we mounted an operation to remove remaining debris which included whole trees which had become wedged between the arches.

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This is a really difficult job and I’ve huge respect for our guys who carry it out. Using chain saws, on little boats, in fast flowing water to tackle objects you can only partly see, is one heck of a challenge.

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But our folk are the best in the business and the bridge (and many others) was left in perfect shape, ready for the next flood!

After every flood we have a number of places we always keep an eye on for stranded fish. Sounds strange, but our local flood plains are so big, and the flows so massive that fish often either get washed out or choose to explore the large expanses of flood water. When the water goes down they are left high and dry!

It’s usually more of an issue in summer floods when the fish are more active, so we were quite surprised when one of our hotspots – Worcester Racecourse – provided a good catch.

Once we’ve spotted stranded fish we have to wait until the water has almost gone so they are concentrated in a small area. Clearly this is a balancing act as if we wait too long they’ll suffocate or be eaten by birds!

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A simple netting operation at just the right time yielded some magnificent pike, bream and roach which were measured and swiftly returned to the River Severn which was now back where it should be!

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We are able to do this work because of the funding we receive from anglers who buy rod licences.

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April

By April things were getting back on an even keel!

For the second year running there was a massive run of elvers (baby eels) on the Severn Estuary. This is against a background of many years of declining numbers and the reasons for it are not understood. However, it means more eels returning to colonise our local river network so it’s very good news!

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We spent a lot of time on the high tides in March and April (when the main elver movements occur) making sure that the elver fishers on the Estuary were abiding by the rules of the fishery. The rules are designed to allow fishing but to limit the amount of elvers that can be taken.

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Most elver fishers are very conservation-minded and much good work was done again this year in stocking Estuary-caught elvers further up the river system to assist their migration.

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We also had a great day at the superb Cobhouse Fishery near Worcester, explaining our work on local fisheries and offering kids the chance to have a go a fishing.

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It’s always a pleasure to see how enthused children are when experiencing angling for the first time. Many have never seen live fish outside a tank.

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We hope that by giving them an early taster some will become hooked!

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May

In May we were able to carry out some improvement works to the River Leadon in Herefordshire. The Leadon has suffered a bit over the last few decades. There have been a number of pollution incidents that have damaged the plants and animals that live in it; in some places run-off from fields is putting large amounts of nutrients and sediments into the water; and in others the banks have become bare and eroded offering little in the way of suitable habitat.

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We worked with the Wild Trout Trust and local angling clubs to carry out some practical bankside improvement works. The aim is to work with the natural shape and flows of the river and create the right conditions for better quality habitat (for fish, plants and insects) to establish themselves.

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We hope that the angling clubs will be able to put their new skills to good use and create more habitat in future years. Turning around the fortunes of a river like the Leadon is neither simple nor quick, but it is possible and the results are very rewarding.

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Our fish survey season got underway. One of the first tasks was the most challenging – catching fish in the mile wide Severn Estuary.

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For fuller details see my earlier post, but we use a huge conical net called a fyke net which we leave staked in place and allow the tide to deliver fish to us!

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As you’d expect we catch a mix of sea and freshwater fish. This time mullet and sea bass were the main species with some fine large eels too.

June

By June our fish survey programme is in full swing (providing there is no flooding!). Every year we survey dozens of sites on rivers and streams across the Severn and Wye catchments.

Most of our survey work is done by electrofishing (passing a small electric current through the water to stun fish). We sample all sorts of watercourses, from tiny streams to major rivers.

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To make sure we can compare the information we gather we survey the same lengths and locations of river.

Overall, results during 2014 were very promising with good numbers of fish and a nice variety of species. We use the information to assess the overall health of the river and to plan and prioritise future action.

A few highlights included:

A nice flounder on the Longdon Brook in deepest Worcestershire

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Native crayfish on the Rivers Onny and Lugg

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Huge hauls of coarse fish (including this tench) on the River Swilgate in Tewkesbury

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Net fulls of lovely trout outside Waitrose in Cheltenham town centre

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July

We were back in incident mode in July. Not because of floods this time, rather a major fire at a factory in Stroud.

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The huge blaze was swiftly extinguished by our friends at Gloucestershire Fire and Rescue but we were very concerned about the possible impacts of contaminated water (used to put the fire out) escaping from the site. Fire-fighting water is always nasty stuff as it picks up chemicals from whatever is burning, but in this case we had two further reasons to be concerned. Firstly, there were a lot of chemicals stored on the site and we were unsure whether they had been burned and got into the fire water. Secondly, the factory backed directly onto the River Frome meaning the water wouldn’t have to travel far to get in.

For several days we worked with the Fire Brigade and the factory owners to prevent water escaping from the site as best we could and monitoring the river and surrounding environment for traces of chemicals or damage to wildlife.

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Some contaminated water did get into the Frome but nowhere near as much as would have without our quick intervention and that of Gloucestershire Fire and Rescue.

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We continued to monitor for several weeks but fortunately no significant problems were found.

In July we also took part in the excellent SOS Fest at Worcester Racecourse. This is an event attended by all the emergency services and is an opportunity for the good folk of Worcester to see some impressive hardware and chat with front line officers.

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Attendance was superb on a very hot Saturday, with numbers measured in the thousands.

We were able to provide lots of advice on flooding and how to avoid it and also to show off our practical skills with the flood barrier challenge.

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A team of our finest chaps put up a length of flood barrier against the clock. Prizes were on offer for people guessing the time taken. Needless to say it got quite competitive!

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For me it was a nice opportunity to do some more relaxed media interviews and spend some time with our fellow emergency responders.

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Ironically in what was a very wet year, by the end of July the top of the River Teme had been reduced to a trickle by a few weeks of dry weather. This is a fairly regular occurrence but causes the problem of large numbers of fish getting stranded in small pools of water that are rapidly drying out.

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So we had to deploy the rescue team again to catch good numbers of salmon and trout and return them to safer locations downstream. By August the rains had return and the previously dry sections of the river became torrents!

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August and September

Sadly it won’t be floods, fires or fish that I remember 2014 for. It will always be the year I lost my mum.

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She died on August 4th after a long battle with cancer. Inevitably most of the rest of the month and much of September for me was about making funeral arrangements and sorting affairs.

October

Immediately after last winter’s floods we carried out inspections of every inch of our flood defences (with help from the army). This was a massive task and took many months.

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Overall they stood up very well to several months of pounding by record-breaking storms but, inevitably there was some damage, especially in the Severn Estuary. Fortunately the Government gave us some extra money to carry out repairs.

By the end of October all of our defences had been restored to full working order, ready for whatever winter 2014/15 throws at us!
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It was good to visit Minsterworth again (see January/February) and see the repairs nearing completion.
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October also saw the biggest emergency exercise on our patch for quite a while. It took place at Shrub Hill station in Worcester and re-created a major train crash.

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Hundreds of emergency responders took part with loads of volunteers playing the part of trapped and injured passengers. It was certainly realistic with plenty of blood and severed limbs scattered around!

It’s very reassuring to see the skills and levels of resources that can be mustered in the event of major incidents. Although only there as an observer I did manage to help quite a few “injured” passengers off the trains! Well, you’ve got to get stuck in, haven’t you!

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November

We responded to hundreds of environmental incidents across our patch during 2014. An unusual one happened in November when a large lorry crashed on the main Hereford to Worcester road, blocking it completely and causing traffic chaos. Nowt to do with us you might say, but in this case as the lorry crashed it went through a hedge and demolished a 5000 litre oil tank on the other side.

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What was left of the tank was buried under a huge pile of debris, making assessment of the impacts somewhat tricky.

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Fortunately there was no watercourse nearby and the spilt oil could be contained and cleaned up without any significant damage to the environment. More importantly there were no serious injuries despite the carnage.

Once again, the incident highlights our close working relationship with other emergency services and the fact you never know what you’re going to get when you’re on duty!

In November, we also welcomed Liz Truss, Secretary of State for Environment, Food and Rural Affairs, to Worcester.

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Along with other partners we were able to tell her about the response to flooding earlier in the year, the new flood defences created across Worcestershire and the challenges we all face in the future.

December

Just to show that things don’t always go to plan! In December we carried out a major fish netting operation at Upton Warren nature reserve near Droitwich. We were working with our friends at the Worcestershire Nature Conservation Trust who manage the site and want to know more about the type and numbers of fish in the pool so they can better plan future management.

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Word was that the large pool (covering a couple of acres) was stuffed full of fish of all kinds. We were looking forward to a bumper haul.

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Many hours later, having deployed our full range of nets and netting techniques we had caught a grand total of two fish, and one of those was a stickleback!

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Our excuses were an unbelievable amount of silt and stinky mud, making access to the water tricky and unpleasant and loads of submerged rubbish, meaning large sweeps of the big nets were impossible. We’re still confident there’s a pile of fish in there – just that we didn’t catch them!

By year end we were starting to see the rivers beginning to rise again as soils became saturated and rainfall began to build up.

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By the middle of the month we had to put up our barriers again at Shrewsbury, being careful to work around the panto timings at the theatre!

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To our huge relief, Christmas flooding didn’t happen, allowing many of us the first Christmas off in three years. Which was nice!

So another eventful year came to an end. What 2015 will bring, I have no idea, but I suspect it won’t be boring!

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Pulling up primroses in Worcestershire

We’ve spent a lot of time pulling up and destroying a pretty water plant at a lake near Pershore in Worcestershire.

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There is method in our madness as the plant concerned is the creeping water primrose (CWP) which can cause serious havoc if left to spread. Also known by its scientific name Ludwigia peploides, it is one of the most wanted on a growing list of plants and animals that are getting established in Britain and have the potential to cause serious damage to our native wildlife and ecosystems. Collectively they are given the scary title of non-native invasive species.

CWP real home is in south America but it has been used widely as an ornamental plant in garden ponds and amenity pools. However, it has spread from some locations into the local environment where it has become established and very successful. In many places it is able to out-compete native plants and forms a dense blanket.

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Not only does this mean that large areas are not available to native plants and animals, CWP can also entirely cover large pools, streams and rivers, making them unavailable for recreational activities but also significantly raising flood risk.

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In France where CWP is widely established millions of Euros are spent trying to control the impacts, while in California a large eradication programme is costing between $6-30,000 per acre to remove it mechanically.

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Fortunately , in Britain CWP is not widely established and is limited to a handful of known locations. We are very keen to keep it this way and are therefore putting considerable efforts to eradicate it where we know about it. Where it is only present in relatively small amounts we can pull it up by hand and destroy the remains. We have to be very careful and thorough as the plant is highly effective at propagating itself from fragments that remain (or worse spread by the pulling process). We will have to keep visiting the sites for several years to ensure it is not returning.

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You can help us prevent the spread of CWP (and other invasive plants) by reporting any sighting using our PlantTracker app. Download it free here: http://planttracker.naturelocator.org

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Find out more about non-native invasive species here: https://secure.fera.defra.gov.uk/nonnativespecies/home/index.cfm

See our top 10 invasive species here: http://www.bbc.co.uk/nature/22126467

Describing flood impacts

When we talk about flooding, or issue flood warnings, we always think about what the likely impacts on people, property and essential infrastructure (big roads, railways, water works, power stations) will be. The more severe the impacts the higher the level of warning. The terms we use to describe flood risk are also governed by the level of expected impacts. This blog provides some examples of those different impacts.

We issue three levels of flood warning: flood alerts, flood warnings and severe flood warnings. You may well be familiar with the graphics and descriptions we use (below).

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We also publish a daily three day outlook of our assessment of flood risk by English County.

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We use green, yellow, amber and red colours to describe the forecast risk. Green represents a very low risk, yellow low, amber medium and red high. The colours don’t just reflect the likelihood of flooding but also the impacts it will cause. We use this matrix to decide the colour to use.

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So what should you expect to see at these different levels of warning or risk? Here are some examples and pics.

Flood Alert and low (yellow) risk

At our lowest level of warning or risk we’d typically expect rivers to be coming out of their banks with water entering floodplains (rivers don’t burst their banks, they simply come over the top!). Impacts may lead to minor disruption and flooding to low-lying roads and gardens.

You might see large areas of farmland in floodplains flooded, sometimes requiring livestock to be moved to higher ground.

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Minor roads flooded and impassable.

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Fords and minor river crossings impassable.

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Riverside paths flooded.

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Deployment of flood defences preventing access

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Flooding to isolated low-lying gardens and access to homes and businesses

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Flood warning and medium (amber) flood risk

When we issue flood warnings and describe flood risk as medium we expect to see significant impacts. These will include flooding to homes and businesses, possibly affecting whole communities. There are also likely to be impacts on local infrastructure and, in some cases, damage to it. Disruption to travel and business are also probable.

The fact that we have issued one or more flood warnings does not automatically mean flood risk will be described as medium in our outlooks. Our assessment of overall risk will depend on the context of the flooding, its overall impact on a County scale and the likely effects on responding organisations.

In addition to the impacts shown above you should expect:

Flooding to homes and businesses.

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Flooding affecting whole, or large parts of, communities.

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Main roads and railways being significantly affected.

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Disruption to public events

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Severe flood warning and high (red) flood risk

For us to issue the highest level of warning or describe risk as high we will be confident that serious impacts will be probable and there may well be a real risk to life as well as property. It is rare for us to issue these warnings or describe risk as high and we will normally have consulted other responders (local authorities, police and fire and rescue) before we do so.

Impacts that may well be seen at this level of warning or risk include:

Major disruption to critical transport routes (eg: motorways and railways)

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Damage or disruption of critical infrastructure (eg: water treatment plants, electicity sub-stations, roads)

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Flooding to large urban areas

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Large scale evacuations of residents

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Overwhelming or damage of flood defences

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So that’s a quick guide on what to expect at different severities of flooding. Don’t forget you can access our latest warnings (updated every 15 minutes) here:

http://apps.environment-agency.gov.uk/flood/31618.aspx

And our 3 day assessment of flood risk (updated daily) here:

http://apps.environment-agency.gov.uk/flood/3days/125305.aspx

How old’s that fish? – Count the rings!

We analyse fish scales to determine the age and growth statistics of fish populations. The information we obtain from fish scales is key to informing effective future management of fish stocks.

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The red areas on the body of the fish are where scales are removed from.  Scales are always removed above the lateral line so as not to damage it.  The lateral line contains sense organs allowing fish to detect movement in the water.

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The photo above shows a fish being de-scaled.  Tweezers are used to carefully pull out scales.  Between 3 and 5 are removed and submitted to the laboratory for analysis.  Scales can grow back and are called replacements, however the early growth history of the fish is absent from these scales so they are of no use for ageing purposes.

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Scales are removed from trout and salmon using a scalpel, the photo shows scales being placed into the storage envelope and a trout being returned to the aerated water.

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This is a close up of a fish scale.  The growth rings are called ‘annuli’.  The age is determined by the number of growth rings.  The length is determined by the spacing between the growth rings. Like tree rings!

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The photo above shows a chub caught at in the River Salwarpe at Droitwich during our routine fish survey in June 2014.  It looks slightly ragged because it recently spawned.  This fish is 319mm long and aged at 9 years old, which is written as 9+.  The oldest chub caught during the survey was aged at 11+!  Eleven years old is a fantastic age for a chub as they grow slowly. 12 years is the maximum life expectancy for chub.

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This is a dace, also caught in the River Salwarpe at Droitwich during our routine fish survey in June 2014.  This fish is 175mm long and aged at 5 years old (5+).  This is a good age for this species; it matures in its second year and rarely lives longer than 7 years.

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The red curve on the graph shows the growth rate of chub in the River Salwarpe. It shows that they grew at an average rate in the early life stages, and then slowed.  This can be attributed to water quality, the availability of food (invertebrates) and the availability of suitable habitat.

Age 1 2 3 4 5 6 7 8 9 10 11
Length (mm) 28 88 160 226 264 292 308 325 335.5 352 380

This table shows the length of the chub calculated during each year class.  From this data we can ascertain the health of fish populations within the river system and compare it to annual trends.  This data is of particular interest to anglers.

Arc Boat 50 arrives in Shropshire!

ARC-Boat number 50 will be the newest recruit to the Environment Agency Shropshire team, helping us issue quicker and more accurate flood warning information to local communities.

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During times of high river levels, the boat may be seen at sites along the river Severn including Montford, Shrewsbury, Ironbridge and Bridgnorth. The boat will be used to survey the river bed of the Severn, Teme and Tern, sending important information to our teams.

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By measuring river flows at a full range of levels our flood models are massively improved. The flow data allows calibration of the flood models that in the past could never be gained across the full range.

Without actual flow data our flood models are theoretical which is OK, but rivers are dynamic systems that change massively over time and this new flow data allows our people to calibrate the models much more accurately. Better calibrated flood models mean much better flood predictions and therefore more timely and correctly issued flood alerts / warnings.

The boats are manufactured by HR Wallingford in Oxfordshire and have been sold to customers around the world including in Canada, New Zealand, France, Azerbaijan. The Environment Agency already has around 30 of these boats in operation across England, but this one is special as it is the 50th to be produced.

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The boats are remote controlled using electric motors and measure the speed and depth of the water to enable it to calculate river flow. They allow us to easily and safely reach places where humans can’t, such as under bridges or during high-flows/floods. Ultra-sound pulses, similar to that used to scan pregnant women, are used to collect important data from the river.

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The boats can operate in river speeds of up to 3 metres a second, meaning they’re capable of dealing with most flows the River Severn has to offer.
As well as collecting flow data, the new boats also scan the river beds. This gives staff information about any debris build up which could cause flooding. It also allows staff to get a much better understanding as to what exactly is happening beneath the river surface.

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Green shoots of recovery on the River Chelt – and lots of them!

It’s just over a year since we finished an ambitious project to realign a section of the River Chelt in Gloucestershire to improve its habitat value and make it more accessible to fish. I’ve been back to have a look how things are working out.

The Project

The River Chelt is a small tributary of the Severn. It rises on the Cotswold escarpment near Dowdeswell, flows through the middle of Cheltenham and joins the Severn at Wainlodes. Over its short length it changes from steep fast-flowing brook to a slowly meandering small river.

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The project was carried out about a mile from the Chelt’s confluence with the River Severn, just before it passes under the A38. The river had been significantly modified here to enable the operation of the now redundant Norton mill. It had been straightened to increase the flow velocity and a small weir installed (photo below). The weir presented a significant obstacle to fish trying to swim upstream, while the steep banks offered little opportunity for wetland plants and animals.

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During September and October of 2011 we realigned the course of the river to bypass the weir and straightened length. We created a new, meandering river channel, which would have been much closer to its original form, and a range of bank slopes.

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In bypassing the weir we opened up a further 6km of the river upstream to fish and a hectare of wetland habitat was created alongside the river.

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However, as you know,you can’t make an omelette without breaking eggs, and I have to confess things did look a bit like a building site when we’d finished.

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What a difference a year makes

Our new section of river has received a number of good tests over the last year. Repeated bouts of summer and winter flooding through 2012 and 2013 resulted in some very large amounts of water being forced through the new channel and in some cases exceeding its capacity and spilling into its floodplain (as it was designed to do).

The speed of plant establishment and growth has been amazing. Not only have the many small trees we planted with the help of local volunteers settled in well, there is already a good variety of wetland plants along the course of the realigned river.

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It’s also very pleasing to see the diversity of habitat developing within the river. Areas of gravel and stones on the river bed should provide good spawning opportunities for fish while fresh silt deposits will be great for feeding birds. Part of the old channel was retained and now provides and excellent refuge for fish and insects.

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We’ll monitor the progress of the site over the coming years to see what species of plants, fish and birds move in, but the initial signs are very promising. Indeed, as if to prove the point, as we arrived a large egret which had been feeding along the river, flapped lazily away!

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Part of a much bigger plan

Our work on the Chelt is just one of hundreds of projects across the country aimed at improving our rivers. It’s all part of the plans to deliver the objectives of the Water Framework Directive which requires us to improve the health of rivers.

We’ve identified where the condition of rivers isn’t as good as it should be and the causes of the problems. There is a variety of issues affecting our rivers: man-made alterations to their shape and form (like here on the Chelt), obstructions like weirs, pollution from single point sources, pollution from run-off of chemicals, soils and nutrients, low flows and the presence of alien species. We’re working with partners to develop long-term plans to tackle them all.

Discover more in our interactive presentation: http://www.informsystem.com/livingwaters/livingwaters.htm