TAC and the Riverfly Anglers Monitoring Initiative

The Thames Anglers Conservancy have become the first organisation on the Thames to have joined the Anglers Monitoring Initiative following a training day with the Riverfly Partnership. The Anglers Monitoring Initiative (AMI) was launched in 2007 to establish groups monitoring their local rivers.
 
Anglers are natural guardians of the river environment and are in an ideal position to monitor the health of the watercourses they fish and know well. The AMI is used alongside routine monitoring by the Environment Agency and ensures that water quality is checked more widely and action taken at the earliest opportunity should any problems be detected.
The trained TAC volunteers will use a simple monitoring technique to record the numbers of eight invertebrate groups, seven of which are riverflies, to monitor the biological water quality of their rivers. Sampling is done on a monthly basis at agreed sites and results given to the Environment Agency. 

 

The training day which was kindly funded by the Environment Agency consisted of both 'in river' sampling and classroom work examining and understanding the range of species that live on the river bed.
Training had to be switched from the main river due to unsafe flood conditions on to a small tributary which proved to have an abundance of life.
 
Louis Kitchen Riverfly AMI Coordinator said: 'It is fantastic to see such enthusiasm for the ecology of the Thames catchment harnessed for the protection of the river. This is a neighbourhood watch scheme for rivers, allowing people who care about their watercourses to keep an eye on water quality. By monitoring the invertebrate life of the Thames, the volunteers trained here will make a real difference to the local environment'.
David Harvey of the Thames Anglers Conservancy said: 'Rivers can look healthy on the face of it but its only when you start to look closely at the invertebrates that a more informed assessment can be made. By doing routine sampling we will detect any inbalances or missing species and crucially then report this information back to the Environment Agency. We are very pleased to have become part of the important Anglers Monitoring Initiative

 

riverfly1

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West Thames groundwater levels still low despite record rainfall

The Environment Agency has published its monthly Water Situation Report for the South East and despite record rainfall, groundwater levels in most aquifers are lower than normal for this time of year in the West Thames area.
 
Summary – April 2012
Rainfall totals for West Thames Area were exceptionally high in all catchment areas in April 2012. The rainfall was sustained throughout much of the month leading to exceptionally high daily mean river flows at most key indicator sites. Groundwater levels in the Upper Thames, Ock and Cotswolds responded with some rise in levels however ground water levels were generally lower than normal for the time of year.
Rainfall
The overall average rainfall total for West Thames Area was 128 mm, 258 % of the April long term average (LTA). All areal rainfall units in West Thames area had exceptionally high end of month rainfall totals for April. The Wey –greensand unit had the highest rainfall total with 161 mm of rainfall, which was 288 % of its April LTA. This was the highest April rainfall total in this unit since records began in 1920. Similarly, the neighbouring Loddon unit also had its highest April rainfall record with 253 % of its LTA. The Enborne and The Cut units also recorded their highest April rainfall totals, although their records only extend as far back as 1961. The Berkshire Downs areal rainfall unit had the lowest April rainfall total with 113 mm, but this was still more than double its April LTA with 222%.
Soil Moisture Deficit (SMD) /Recharge
As a result of the high rainfall totals in April effective rainfall was exceptionally high in all West Thames Areal rainfall units too. The highest effective rainfall was in the Wey – greensand unit with 540 % of the April LTA. The Cotswolds West had 508 % of its LTA, and the Upper Thames had 500 % of its LTA. On average the areas total effective rainfall was 374 % of the April LTA. By the end of the month all areal rainfall units had soil moisture deficits to 0 mm. This means that at the end of April soils were saturated.
River Flows
With the exceptionally high rainfall in April, daily mean river flows responded rapidly with most key indicator sites going from exceptionally low to exceptionally high. At the end of April most rivers were still rising with 11 of the key indicator sites having exceptionally high flows. Owing to the low flows and dry soils at the start of April the rivers in West Thames Area were able to contain most of the rainfall and surface water runoff within their channel capacity and floodplains. As a result of the increase in river flows in all catchments the April month mean flows suggest that most rivers have responded to the rainfall with 6 key indicator sites now being normal for the time of year. The Upper Wey month mean for April was notably high and the Lower Wey and Cherwell was above normal. However the River Coln month mean remained exceptionally low and the River Kennet was notably low. It is expected the recovery in river flows will be short lived unless we see significantly heavy rainfall in May.
Groundwater Levels
Groundwater levels at some West Area key observation boreholes showed a response to the April rainfall. In the Oolitic Limestone of the Cotswolds and Upper Thames and in the Corallian of the Ock catchment groundwater levels increased slightly. Despite this, groundwater levels in most aquifers are lower than normal for this time of year. Only the Great Oolites as measured at Ampney Crucis in the West Cotswolds are normal for the time of year and the groundwater levels at Marcham in the Corallian of the Ock are above normal. At the end of April Stonor Park observation borehole in the West Chilterns remained dry. Environmental Impact There were 27 flood alerts issued in April but no flood warnings were needed.
With the increase in river flows the number of active constraints on abstraction licences steadily declined throughout April. By the end of the month there were only 5 flow constraints in force preventing abstraction to two public water supply licences owned by Thames Water and three significantly smaller private licences. The high rainfall quantities and increase in rivers flows allowed the Environment Agency to cease running the Letcome Brook augmentation scheme in April. The scheme has been running almost continuously over the past 18 months.
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Biogen fined almost £10,000 for polluting a Bedfordshire stream

Leading anaerobic digestion company Biogen UK Ltd been fined £5,000 by Bedford Magistrates’ Court for polluting one mile of a Bedfordshire stream.
The Environment Agency said the pollution was avoidable and it should have been notified sooner so that the incident could have been better managed. A large quantity of digestate from an anaerobic digester overflowed when a pump was left on overnight at the company’s Clapham Biogas Plant on 19 November 2010. A member of Biogen staff saw liquid running down the road as they arrived at work at 4am.
An hour later another employee saw more liquid in a field close to their own pig unit, operated by Bedfordia Farms Ltd. Biogen is part of the Bedfordia Group. The tank had no alarm system and had to be turned off manually. Mrs Miriam Tordoff, prosecuting, said the company knew it needed an alarm on an underground tank following a similar incident two months before at another of its sites near Rushden. She said that by the time the Agency had been told of the pollution it was late in the afternoon and an investigating officer had trouble assessing the effect and taking samples as it was dark. He arrived on site within half an hour after being notified. A building housing the anaerobic digester tank had a tide mark on the door about 6in from the ground indicating the level the liquid waste had reached. The officer also saw puddles on either side of the road and a trench full of liquid in the field. The trench had been created by staff to try to prevent the liquid reaching their pig unit. They had also tried to dam the stream.
Mrs Tordoff told Bedford Magistrates’ Court that in daylight the following day it was clear that the pollution had not been held back by the dams and the company was advised how to improve their effectiveness. The pollution spread beyond the dams for at least two more days. She told magistrates that the company’s environmental permit stated clearly that overfill alarms and protection devices had to be installed on all fixed tanks for the treatment and storage of waste. The need for alarms had been raised a month before during a site audit. “During the audit a number of site warnings were given for breaches of the permit, including the one for failing to have the alarms and protection devices on two tanks,” she said. Managers of the site told Agency officers that during an upgrade to the site in June 2010 the original alarm system was deactivated and due to an oversight it was not replaced.
They estimated a loss of 300,000 litres of digestate but believed only 10,000 litres escaped off-site. It had taken all day to clean up the site. Since the pollution a system of alarms, nightly checks and twice weekly electrical checks had been introduced. The company was ordered to pay full Environment Agency costs of £4,677. After the hearing Senior Environment Officer Charan Sekhon said ‘’ It was an avoidable accident that resulted from Biogen’s failure to comply with their environmental permit.
This case sends a clear message to Biogas Plant operators that they must ensure that they have a robust infrastructure and pollution prevention measures in place.
Biogen pleaded guilty to: 1. On or about 19 November 2010, you did cause the entry into inland freshwaters, namely a tributary of the Ravensden Brook, of poisonous noxious or polluting matter, namely liquid digestate, at Twinwoods Farm, Oakely Littlewood, Clapham, Bedfordshire, MK41 6BL Contrary to Regulation 12(1)(b) and regulation 38(1)(a) of the Environmental Permitting (England and Wales) Regulations 2010
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Serious oil spill along the River Bourne

Environment Agency officers have been out since first light to assess the extent of a major oil spill along the River Bourne in Hampshire– one of the country’s most important salmon fishing rivers.
Environment Agency officers are doing everything they can to minimize the effects of the spill. Booms and absorbent pads have been placed in the water to contain the oil pollution. No dead fish have been reported, but fisheries officers will continue to keep a close watch on river life. All efforts are being deployed by Environment Agency staff to minimise further impact on to the river and local wildlife.
Officers will continue to monitor the situation and respond as necessary.
Environment Agency Manager Simon Moody said: "This is a major oil spill along the River Bourne. Environment Agency officers have been out since first light doing everything they can to minimise the impact on the environment. We will be overseeing the clean up and will launch a full investigation into the cause. "We advise people to keep themselves and their pets out of the water until the incident is resolved."
The public are our eyes and ears and if anyone has any further information regarding this incident please call our 24 hour Incident Hotline number on 0800 807060.
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Angling Trust calls for a fresh approach to water supply and storage

The Angling Trust has called on politicians to recognise that England needs a completely fresh approach to water supply and storage in order to end the chronic wastage of water in times of flood and the environmentally damaging over abstraction of vulnerable rivers in times of drought.
(Picture Thames Water
The Trust has highlighted the situation in the Thames Region where despite a 7% increase in population in London and the South-East since 2001 no new reservoirs have been built for more than 40 years. At the same time demand for water has reached a record level of 1000 litres per person per week, putting huge strain on the network at the expense of the environment.
National Campaigns Coordinator Martin Salter said: “As any angler knows, billions of gallons of floodwater rush out to sea at times of high rainfall yet a few weeks later water companies may be applying for drought orders to suck dry our already depleted chalkstreams and other vulnerable rivers. It is utter madness that governments of both persuasions have failed to plan for the needs of expanding populations and the challenges of climate change which mean more extreme weather conditions including both drought and floods.
In the Thames Region in particular it beggars belief that no new reservoir has been given planning permission for the last 40 years and that proposals for a much needed Abingdon Reservoir were rejected in 2010. It is just plain commonsense to store in times of plenty to get through periods of scarcity.”
The Trust has made its call at a time when most of England is officially in drought, groundwater levels are at historic lows following two years of exceptionally low rainfall and yet there are 150 Environment Agency flood alerts and 32 flood warnings in place as the UK experiences one of the wettest Aprils since records began.
Water minister Richard Benyon acknowledged that the current deluge will do little to end the drought when he said: “ I’m afraid we need more rain as what we’ve had isn’t filling up the ground reserves that we need in order to cope with the drought.”
Angling Trust Chief Executive Mark Lloyd added: “Politicians must realise that water is a precious resource which must use more carefully and stored more wisely. There is an urgent need to invest in greater storage to avoid the widespread depletion of groundwater levels and river flows. Much more should be done to reduce the demand for water – including the introduction of universal metering – and more of the supply should come from reservoirs rather than via unsustainable abstractions.”
Low flows in rivers are highly damaging to a host of aquatic wildlife, to fish stocks and to fishing, which is an important pastime for millions of people in the UK and generates £3.5 billion for the economy. Low water levels do great damage to fish populations and can destroy spawning habitat.
Key areas where the Angling Trust believes action should be taken include:
• Building new storage reservoirs to capture winter rainfall
• Fixing water supply leaks (although this becomes less and less cost-effective as some leaks are very expensive to fix)
• Requiring all new developments to be water neutral – i.e. very water efficient and the developer to be required to retrofit water efficiency measures in homes and industry in the same water catchment equal to the amount of new water used; • Removal of drainage to allow water to soak into the ground
• Major public awareness campaigns to reduce water usage from 160 litres per person per day; • Universal metering to ensure that those who waste water pay for it directly

To join the Angling Trust and for more information go to http://www.anglingtrust.net
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River Crane Pollution briefing from the Environment Agency

The Environment Agency have issued a update on the River Crane pollution following the devastating incident in October 2011. The Pollution incident which decimated all fish is being investigated by the EA.
Carp killed by Sewage
 
Current remediation of the River Crane
On 17 February 2012 the Environment Agency, Thames Water Utilities Limited (Thames Water) and Total Waste Management Solutions Ltd (TWMS) jointly inspected the River Crane. Together we identified four locations along the river and adjacent areas where materials from the pollution incident needed to be removed.
• Crane Park Island Nature Reserve above Shot Tower;
• the A30 road bridge near Eastern Perimeter Road;
• the footbridge where the river passes behind Cranford Infant School;
• the A4 road bridge near the White Hart pub.
Given the time which had elapsed since the initial sewage pollution incident, we instructed Thames Water to undertake the required remediation works.
Over the past month, Thames Water and TWMS have collected, removed and disposed of the upper layers of sewage contaminated silt and sediment. The contaminated materials were secured and removed to Mogden Sewage Treatment Works by tanker. Our officers, along with employees from Thames Water, inspected the areas that had been remediated on 13 April 2012.
We are waiting for the results of samples taken by Thames Water to confirm if the remediation works have been satisfactory. Future restoration of the River Crane We will continue to assess the long term impact of the pollution incident on the ecology of the river throughout the summer and autumn. When we have completed our assessment we will make proposals for fish restocking and habitat restoration in conjunction with the other members of The Crane Valley Partnership. We want to ensure the River Crane is restored, as far as possible, to the condition it was in before the incident, and that polluters are held accountable where an offence has been committed.
We cannot comment on the proposed value of any river restoration fund at this time. Although we are interested to know the basis of the figures proposed we have had no involvement in any discussions about the fund. Any restoration fund must be aimed at rectifying the evidence based impacts caused by a pollution incident on the river and its adjacent areas and not just a means of self imposed sanction.
What happens next?
We are continuing with our criminal investigation. People affected by the incident are being contacted for further details and invited to provide a witness statement. If you have any information about this pollution incident or wish to give a statement, please contact us on 03708 506 506 and ask for Richard Cattan or Andy Grant. 
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Thames Anglers’ Conservancy joins important eel monitoring programme

Thames Anglers' Conservancy joins important eel monitoring programme

The Thames Anglers' Conservancy in partnership with the Zoological Society for London has taken on the monitoring of the newly installed eel trap at Molesey weir.Ten volunteers from the TAC have received training in how to record any eels that are caught in the trap during the migratory season.
ZSL training volunteers at Molesey Weir
Research over the last 30 years has shown that the European eel (Anguilla anguilla) is facing a range of threats that are severely impacting on their recruitment – and potentially their populations in freshwater – leading to its 2008 Critically Endangered classification in the International Union for Conservation of Nature’s Red List of Threatened Species. The number of young eels joining the resident adult population across European catchments is believed to have declined by up to 95% since the early 1980s.
In 2005, in response to this alarming decline, the Zoological society of London set up its Eel Monitoring Programme.
Joe Pecorelli of the Zoological Society for London said: “Thanks to the help of partnership organisations such as the Thames Anglers' Conservancy we now have 12 monitoring sites in Greater London all contributing to this unique and important study. The information we get feeds into the eel management plan for the River Thames and allows us to make evidence based conservation decisions”.
“The European eel has one of the most fascinating of all animal life-cycles. Beginning life as leaf-shaped larvae known as a ‘leptocephalus’ in the Sargasso Sea, they make an incredible migration across the Atlantic Ocean to the rivers and shallow coastal waters of Europe”.
Joe added: “We are delighted that the Thames Anglers' Conservancy has agreed to take on the monitoring at Molesey Weir and we hope this will be the start of a very productive partnership between our organisations."
Dave Harvey Chairman of the TAC said “Thames eels face many challenges getting this far up the river including trying to navigate their way through the millions of tonnes of sewage entering the Thames Tideway each year. Molesey Weir is significant, as it is the first barrier on the non-tidal Thames, so we are looking forward to see how the monitoring progresses. As anglers we are acutely aware of how important this conservation programme is and we are delighted to have the opportunity to assist in partnership with the ZSL.

More information on the Zoological Society of London’s work with European eels, within the River Thames and abroad please visit the ZSL website and the Marine & Freshwater team’s facebook page: 
http://www.zsl.org/conservation/regions/habitats/marine/
https://www.facebook.com/ZSLMarineAndFreshwaterConservation

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South West Water fined for discharging poor quality sewage effluent

South West Water has been ordered to pay £20,226 in fines and costs for discharging poor quality sewage effluent into the Tamar estuary. The case was brought by the Environment Agency.
Camels Head sewage treatment works is one of five Plymouth treatment works serving a population of approximately 62,000 in the western area of the city.
Effluent must be treated to certain standards laid down in the site’s environmental permit. Treated effluent is discharged into Weston Mill Lake, a tidal creek within the Devonport dockyard complex. The discharge point is close to the Tamar estuary Special Area of Conservation and a local shellfishery.The Camels Head treatments works has been the subject of numerous complaints about odours from the site.
On February 16, 2011 South West Water reported to the Agency that an effluent sample taken six days earlier had failed the required standard and that the treatment works was continuing to discharge poor quality effluent. An Agency officer visited the works and was told the site was experiencing a series of problems. There were longstanding problems at the inlet screens which remove bulky materials from the sewage as it enters the works. This had resulted in rags and other debris passing forward into the primary settlement tanks which, in turn, reduced the effectiveness of the biological treatment. The situation was made worse by the fact that five out of 16 paddle aerators used in the treatment process were broken. South West Water said there had been further problems from vandalism where foreign objects had been deliberately thrown into the final treatment tanks.
As a result, the sewage had not undergone the full treatment process and the final effluent was much stronger than it should have been. The sample taken on February 10, 2011 contained four times the maximum permitted limit for suspended solids and had a biochemical oxygen demand (BOD) almost twice the maximum limit. BOD is a measure of the rate at which bacteria remove oxygen from the final effluent. The higher the BOD the greater the risk of fish and other aquatic life suffocating through oxygen starvation. South West Water must report any effluent quality failures to the Environment Agency within 24 hours. The Agency wasn’t made aware of problems at Camels Head until 6 days after the non-compliant sample was taken.
Records kept at the sewage works showed there had been problems at the site for a couple of weeks prior to February 16, 2011. Weston Mill Lake is used by the Ministry of Defence (MOD) to train divers.
The Agency was unable to alert the MOD to problems at Camels Head because of the water company’s failure to report the difficulties it was having at the works. ‘We expect water companies to take active steps to resolve problems at their sewage treatment works as soon as is practicably possible. There were many symptoms of problems at Camels Head prior to the failing sample being taken that South West Water should have acted on. The pollution could have been avoided had the company addressed the problems with the inlet screens sooner. This lack of action resulted in the Tamar estuary and nearby Special Area of Conservation being put at risk,’ said Sarah Taylor for the Environment Agency,’ said Sarah Taylor for the Environment Agency.
Appearing before Plymouth magistrates yesterday (April 16), South West Water, of Peninsula House, Rydon Lane, Exeter was fined a total of £16,000 and ordered to pay £4,211 costs after pleading guilty to four offences of discharging noxious, polluting and.. matter from Camels Head sewage treatment works, Plymouth in breach of the Environmental Permitting Regulations 2010. The company was also ordered to pay a £15.00 victim surcharge. The court acknowledged the treatment works had occassionally been targeted by vandals. Sarah Taylor emphasised that anyone engaged in vandalism should recognise their actions could interfere with the treatment process and harm the environment. Since these pollution incidents, South West Water has agreed an action plan to improve compliance with standards at its sewage treatment works and so reduce the risk of illegal discharges from its site.
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Angling Trust calls for restrictions on water users as drought zone spreads

Reacting to news today that the Environment Agency has declared a further 17 counties as 'drought zones', the Angling Trust is calling on more water companies to act responsibly and introduce water use restrictions now. Companies have the power to impose Temporary Use Bans, and should do so, rather than taking risks with the environment.
Bringing in restrictions now will make it less likely that environmentally damaging 'drought permits' – which would allow the abstraction of even more water than usual from our shrunken rivers – will be needed later in the year. Hoping for the best isn't good enough when there is so much at stake. Simple and sensible restrictions, such as banning the use of hosepipes must not be regarded as a last resort.
They are an essential first step to minimise the impact of drought on our irreplaceable rivers and streams. On the back of two dry winters and with widespread depletion of groundwater levels and river flows, the Trust believes that more needs to be done now to reduce the demand for water through hard hitting public awareness campaigns and preventative measures to stop wasteful and unnecessary uses such as car washes and watering of lawns. Recent rain has been welcome for gardeners, but has done very little to improve the overall supply of water. Low flows in rivers are highly damaging to fish stocks and to fishing, which is an important pastime for millions of people in the UK and generates £3.5 billion for the economy, often in rural areas.
Low water levels make fishing impossible and also do great damage to fish populations: Reduced flows lead to higher temperatures and reduced oxygen levels which make fish more vulnerable to pollution; Pollution from agriculture, sewage effluent and urban run-off is more concentrated; Gravels where fish lay their eggs, and invertebrates live, become caked in sediment or exposed to the sun, reducing regeneration of populations of both; Fish become more susceptible to disease and vulnerable to predation from otters, mink, cormorants, goosanders and herons – by abstracting too much water from rivers we upset the natural balance;
Barriers to migration of fish, such as man-made weirs, become impassable, preventing fish from moving to and from feeding and spawning areas – fish passes often rely on sufficient flow to be effective.
The Angling Trust calls on the Government to adopt the measures set out in the Blueprint for Water, which is an integrated strategy for managing water resources more effectively to ensure security of supply and healthy wetlands and rivers for wildlife and recreation. It is supported by 14 organisations including the Angling Trust, RSPB, WWF and the National Trust and was conceived nearly 5 years ago, but there is little evidence that the government is taking the necessary steps to implement it.
Priority areas where the Angling Trust believes action should be taken include:
  • Building new storage reservoirs to capture winter rainfall; Fixing water supply leaks (although this becomes less and less cost-effective as some leaks are very expensive to fix);
  • Requiring all new developments to be water neutral – i.e. very water efficient and the developer to be required to retrofit water efficiency measures in homes and industry in the same water catchment equal to the amount of new water used;
  • Removal of drainage to allow water to soak into the ground; Major public awareness campaigns to reduce water usage from 160 litres per person per day;
  • Universal metering to ensure that those who waste water pay for it directly;
  • Removal of penalties for water companies introducing water use restrictions such as hosepipe bans.
Mark Lloyd, Chief Executive of the Angling Trust said: “if we have a dry summer, many of our rivers and lakes will experience a catastrophic loss of fish and other wildlife. We should not be wasting water washing cars and keeping lawns green when our aquatic environment is under such incredible pressure. Cars do not need to be cleaned, and lawns recover very quickly even after going yellow, but fish populations can take years to recover from a bad drought. Water companies should be encouraged to introduce water restrictions now to avoid having to prevent having to implement emergency drought measures later in the year. Tap water can be better quality than the water people buy in plastic bottles for £2 a litre, but yet we behave as if it were free and unlimited. It's not and it's about time that we started to value it as an essential ingredient for life."
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West Thames Area Drought Statistics March 2012

 

The Environment Agency West Thames area report for March 2012 reveals there was only 38% of the March long term average rainfall and only 17% of the March LTA of effective rainfall. Most of the key river sites were exceptionally low for the time of year and all but one of the key groundwater monitoring sites had lower than normal groundwater levels at the end of the month. 

 
Rainfall
March was another dry month with 38% of the LTA monthly rainfall for Thames West area. The majority of this rainfall occurred in the first week of March. Most areas saw some rainfall in the middle of the month but the last two weeks of the month were dry. Rainfall was greatest in the Chilterns West which had 51% of its March LTA rainfall. All of the other West Thames areas had less than half the normal March rainfall with the Wey catchment having the least with only 29 % of its March LTA. The 2011- 2012 winter period, from October to March, was the 5 th driest winter period in the West Thames since our rainfall records began in 1920. In total West Thames had only 63% of the usual winter rainfall, making this the second consecutive winter with below average rainfall. The 18 months since October 2010 have been the 2 nd driest corresponding period for West Thames Area, only 1921-22 was drier. The south east of England remains in drought status.
Soil Moisture Deficit (SMD) /Recharge
SMDs were higher than normal in all West Thames catchments at the end of the March with the greatest being in the Ock, Thame and Berkshire Downs. The soil moisture model indicates that SMDs did not return to zero (as usual) this winter in these catchments, as well as in the West Chilterns. There was limited effective rainfall in March across much of the West Thames this month. The Cherwell had the most effective rainfall but this was significantly less than we would normally expect at this time of year with only 36% of the March LTA. In the Ock and Thame catchments there was no effective rainfall at all in March. The overall effective rainfall for the area was just 16% of the normal March amount. Over the 2011-2012 winter period effective rainfall was 17 % of the LTA. All catchments had a third or less of the effective rainfall that we would normally have over this period. Effective rainfall was highest in the North Downs (Hampshire) with 33%, followed by the Wey (Greensand) with 32% and the West Cotswolds with only 30% of the winter LTA. The Upper Thames only had 7% of the normal winter effective rainfall and the Ock and Thame had no effective rainfall at all.
River Flows
Monthly mean river flows in March were exceptionally low at all but three of our indicator sites. Only the River Wye at Bourne End and the River Wey measured at Weybridge and Tilford had month mean flows that were notably low as opposed to exceptionally low. The River Thames at Windsor and the River Thame at Wheatley both recorded their lowest March mean flows, whilst the Rivers Coln and Cherwell had their lowest March flows since 1976 which is the lowest March flow for these sites. The River Ock also had its second from lowest March mean flow this year since the gauging station opened in 1979. The driest March in the Ock record was in the low flow winter of 1992.
Groundwater Levels
Groundwater levels at most sites have changed very little over the past month. Only in the Oolites have levels changed very much since February. In the Great and Inferior Oolites of the West Cotswolds and Upper Thames groundwater levels continued to decline following limited recharge over the winter period. At Fringford OBH levels did rise in March although they remained exceptionally low for the time of year.
The full report and information for all Thames Regions is on the EA website
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