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Myth busting water quality

There are lots of myths and rumours on social media about the water quality in Clevedon Marine Lake, so we thought that we’d set the record straight.

Myth #1: The water in Clevedon Marine Lake is dirty

We test the water regularly from April to October. Since we started testing, 80% of the results have been good or excellent. To put that another way, we have had 8 weeks of poor water quality since summer 2018. The lake is usually cleaner than the sea and rivers.

Myth #2: The lake is full of dog poo

‘I heard that when the lake was drained they found a load of dog poo bags at the bottom.’ This is one of the best untruths we saw on Facebook. This didn’t happen. It’s true that bacteria on animals and humans get into the water, which is why we don’t have dogs in or by the lake. But, poor water quality is caused by a combination of four things:

  1. Warmer water temperatures. The lake is quite small and can reach 30 degrees centigrade, which is the perfect temperature for bacteria.
  2. More people in the lake. People bring germs.
  3. Mud getting stirred up. When people stir up the mud in the bottom, it blocks the sun’s UV rays which would naturally kill bacteria.
  4. Big gaps between over-topping tides. The tide must be higher than 12.6 metres to refresh the lake.

Myth #3: The lake’s brown colour is dirt.

Clevedon has the highest tidal range in the world. This means that the silt in the sea never settles. This doesn’t mean that the water’s dirty, but it does cause problems. The mud settles on the floor of the lake where it becomes compacted and stagnant. We drain the lake every March and October for a week to dig out as much mud as we can — this costs £10k a year!

Myth #4: Diet cola kills germs from wild swimming

This doesn’t say much for diet cola, but some swear that it kills bugs from open water. However, it is a good plan to wash after you swim in wild (not treated with chlorine) lakes, pools and the sea. Wash your hands before you eat and have a shower when you get home.

You can help us

Clevedon Marine Lake is run by volunteers. You can support our charity to keep the water clean by:

  • Taking all litter home with you
  • Keeping your dog away from the lake
  • Not using bacon for crab bait
  • Donating so that we can keep on testing the water and draining the lake to clear out the mud

Join in: swim challenge

Fancy a challenge? On the weekend of 14/15 August, you can set yourself any swimming challenge you like. It might be a distance — maybe you’ve always wanted to swim 1km, 5km or even 10km. It might be swim in somebody’s memory or a swim in a funny costume. You can do it on your own or as part of a team.
Whatever you choose, this is your chance to be a part of a national challenge and raise money for a fantastic cause at the same time. You’ll get a free event swim cap and have the chance to win some amazing prizes.

What’s the charity?

The challenge is set up by Level Water and lakes all across the UK are taking part. Level Water is a national charity that provides bespoke, 1-1 swimming lessons to children with disabilities. They currently work in 80 pools and provide 20,000 lessons to 500 children, but this is all at risk. Their income has been hit hard with the cancellation of 2020 and 2021 events, which is why they’ve teamed up with the Outdoor Swimming Society to run ‘Lakes for Level Water’ for a second year giving you the chance to be part of an incredible challenge and giving Level Water hope of survival.

What’s more, Clevedon Marine Lake will get 20% of all the funds raised. We are raising money to build a disabled changing room and toilet by the lake, and to store the disabled hoist that we raised money to buy with our winter swimming challenge. We believe in providing access for all to Clevedon Marine Lake and opening up opportunities for more people to enjoy the benefits of water activities, which is why we’re so happy to be working with Level Water.

Want to take part?

Go to and register.

Join our fundraising team and start raising money. There are loads of fantastic prizes to be won!
Please note: the lake will remain open to the public throughout both events. If you’re not taking part, please come and give the swimmers your support! 

Water quality excellent despite crowds

It’s been a busy couple of weeks at Clevedon Marine Lake. From dawn to dusk, people have been arriving in their droves to swim, paddleboard and enjoy being by the water.

Over the last few years, crowds plus warm water temperatures have led to a drop in water quality. But, not this year. We have been taking regular samples to be tested at a local lab and the water quality has remained ‘excellent’.

Safe and fun

Keeping the lake safe and clean is our priority. Every morning, our volunteers clean up litter from the day before. But this hasn’t been easy. Not only have people been leaving lots of litter, but also broken glass and even dog poo. This is dangerous for people with bare feet, children playing and risks affecting the water quality.

You can help

To help us keep our lake clean and safe for everyone, please:

  • take all litter home with you or use the big wheelie bins on the upper promenade
  • don’t bring your dog to the lake
  • avoid single-use plastics where you can
  • don’t bring glass bottles
  • buy wooden crabbing lines
  • keep barbecues off the ground (they damage the concrete when hot)

You can also donate to support our charity’s work or volunteer to help the morning clear-up.

If you’re spot anything that’s broken or damaged, please get in touch. If you’re concerned about anti-social behaviour at the lake you can report it to Avon and Somerset Police here.

Plugging the lake

Clevedon Marine Lake’s technical team came with an ingenious way of fixing a leak this week.

We’d noticed the level of water in the lake dropping, and found a leak next to the sluice gate in the lake wall. Engineers fitted the sluice gate during the 2015 refurb so that we could drain the lake for maintenance. But the pressure of the water inside the lake meant that a small amount was leaking out in between over-topping tides.

That’s when our technical team came with an ingenious but simple plan to stop the gap using sawdust and sand. Tim Clouter, the trustee for Clevedon Marine Lake who looks after the volunteer technical team, realised that sand and sawdust was a time-proven method for blocking leaks. But the challenge was how to get the mixture in the right place.

After chatting through a few ideas, which included Tim diving down in his scuba diving kit or fellow technical volunteer Nick Haliwell going snorkelling, Tim hit upon a very clever hack. “I got the polythene bag that the sand came in and made a quick-release clamp that went on the end,” he said. “We had a pin on a string, and when you pulled the string, the clamp fell off and dumped the mixture in the right place.”

Some of the other volunteers were a bit sceptical of Tim’s idea, but it worked so well that he used the same method to sure up another small leak in the lake wall. Tim then had the job of rescuing a few stranded shrimp who’d been living in the leak on the sea-side of the lake wall and scooping up a bit of sawdust that had got away. But the beauty of Tim’s method is that there was no risk to the lake environment or water quality.

A team of volunteers works hard every single day to look after Clevedon Marine Lake to make it a safe and clean environment for everyone to enjoy. You can support our hard work by donating or volunteering yourself.

You can listen to Tim being interviewed by BBC Radio Bristol here. Please go to 1:17:00 on this clip.

Mud, eels and treasure

Tonnes of mud, wedding rings, Go-Pros, eels and broken glass… If you’ve ever wondered what’s under the water in Clevedon Marine Lake, now you know!

Twice a year Clevedon Marine Lake volunteers open the sluice gates to drain out the water to remove tonnes of silt build-up. With the second-highest tidal range in the world, the Bristol Channel around Clevedon moves too much to let the silt settle on the river bed. Every time the tide tops over the lake’s wall, it deposits the mud that sinks to the bottom and builds up over time. To keep the lake deep enough for swimmers, canoeists and paddle-boarders, we need to get the digger in.

On March 19th we opened the penstock and sluice gate, letting the water in Clevedon Marine Lake slowly drain out.

Then, on Saturday 21st, a working party of around 60 volunteers trawled the lake bed to remove debris, rescue sea creatures and search for missing treasure. Among the treasures found were two GoPro cameras and three rings.

Caspar Clarke was our youngest volunteer to find a ring using the metal detector that he got for Christmas. After his mother posted a photo of 9-year-old Caspar holding the ring on the swimmers’ Facebook page, we managed to reunite it with its owner, Andrew Mitchard.

“I lost my wedding ring while paddle-boarding somewhere in Clevedon Marine Lake last June,” said Andrew. “With the help of a nine-year-old with a metal detector and a bit of social media assistance, it’s only gone and turned up! Nine months at the bottom of the marine lake, and it’s still in reasonable condition. Rumour has it my wife is planning to talk to me tonight! I would like to say thank you to Caspar and all at Marlens.”

Caspar with the ringA lot of people don’t realise that Clevedon Marine Lake is run by a charity and a dedicated team of volunteers. These volunteers don’t just organise clear-ups when the lake is drained; they also litter-pick, clean, mend and even pick up dog poo pretty much every day. They also clean, catalogue and store all items found in the lake with the hope of returning them to their owners.

“Cleaning up the lake was quite fun, especially when we found cool things like eels and rings! I felt really excited and surprised that I actually found something,” said Caspar. “The man was obviously very happy for me to find it, and I was happy because he got his ring back.”

We are now working hard to prepare for what we expect to be a busy summer. We’re putting in two sets of new steps, adding extra water quality tests and redesigning the website and lake signage. This will make it easier than ever to enjoy the lake, keep it clean and safe, and observe social distancing for as long as it’s in place.

We know that fresh air and exercise support our immunity and is good for our mental and physical health, so we don’t want to discourage visitors. But we would ask that people help us keep the lake clean by not bringing their dogs, taking home their litter and that they donate £2 every time they visit.

To donate, please click here or find the white donation boxes around the lake (emptied daily). To become a volunteer, please email

Get stuck in!

Every year, we drain the lake to remove the silt build-up. But this is also our chance to clean seaweed and algae off the steps, fix broken or worn fittings, add new features and facilities… and search through the mud for lost property!

All this work is done by a team of volunteers. And you can help too. On Saturday 20th March, we will meet by the lock-up on the upper-promenade near the coastguard’s hut from 9 am. Or, you can turn up at any point and ask a volunteer in a turquoise tabard what you can do.

The drain down timetable

Friday 19th March:

  • Open penstock, 9-10 am and put out barriers.
  • Close penstock, 7 pm.


Saturday 20th March, 9 am to 6 pm: 

  • Open lower lake penstock to drain out residual water, then close it
  • Search lake bed for lost property and bring anything of value to the shuttered
    shelter to be recorded
  • Remove debris from lake bed. Check the edges carefully for broken glass
  • Scrub weed from steps and handrails, using wire brushes
  • Tighten bolts
  • Pressure wash splash pool and slipway

Monday 22nd to Friday 26th March:

  • Digger to remove silt from the lake bed. No public access during this time.

Friday 26th March 6 pm onwards (after digger finishes):

  • Re-position any buoys which have been disturbed by the dredging.

Saturday 27 March 9 am-12

Note: High tide (6 am, 6.15 pm) may start to refill the lake depending on the weather.

  • Clean mud off the lower promenade
  • Remove mud left by the digger on the ramps and upper promenade
  • Put up flags on all the remaining flagpoles
  • Remove barriers

The lake will refill from the overtopping tide at 7.30 am on Sunday 28th March.

Voluntary work is allowed under government guidance. Please make sure that you keep socially distanced, bring your hand sanitiser and your own gardening or rubber gloves. Please don’t come if you or anyone in your household has symptoms of coronavirus, or if you have been told to self-isolate.

All ages and abilities are welcome. Volunteering work is done at your own risk.

Can’t help this time?

Please consider donating to Marlens, the charity that looks after the lake.

Join in at our AGM

Clevedon Marine Lake will be holding its Annual General Meeting (AGM) on March 21st at 7pm. In keeping with lockdown, it will take place over Zoom.

Clevedon Marine Lake is run by a charity called Marlens (MARine Lake ENthusiastS), and every year we hold a meeting for everyone who enjoys the lake. Last year, the AGM took place on March 15th just a few days before the country went into its first lockdown. We talked about upcoming events with an idea that some would probably be cancelled but with no idea of the impact of the Covid-19 pandemic.


This year, the agenda is as follows:

  1. Welcome and Apologies
  2. Approve Minutes of Previous AGM (15th March 2020)
  3. Trustees Report
  4. Financial Report
  5. Election of Trustees & Officers

Our constitution requires that one-third of the trustees retire at each AGM.

Retiring: Bob Slee
Steve Price
Joe Norman

We have the following Trustee candidates, who need to be approved by members:

Laura Nesbitt: Proposed by Joe Norman, seconded by Rowan Clarke

Quentin Crew: Proposed by Joe Norman, seconded by Rowan Clarke

  1. Member Resolutions – none have been received so far. Deadline 9 March.
  2. Questions, Answers and Open Discussion

Please e-mail a copy of your questions to the Chair prior to the meeting:


  1. Trustees:  We currently have 11 trustees. Chris Blades, Barry Cherokoff, Rowan Clarke, Joe Norman, Steve Price, Bob Slee, Laura Nesbitt, Quentin Crew, Hilary Jenkins-Spangler, Mike Perrott and Myles Podmore.  Laura and Quentin were co-opted as trustees during the year.  This needs confirmation by the members at the AGM.

1/3 of the charity trustees must retire at each AGM, so Bob Slee, Joe Norman and Steve Price are retiring this time. All three have now completed three stints as trustees, so are not available for re-election until a further 3 years have passed.

Joe Norman and Steve Price will still be around and happy to help.

Bob Slee is retiring as a trustee but is willing to remain as treasurer.

Clevedon Town Council is able to appoint one trustee and in January 2018 they appointed Councillor Barry Cherokoff for a 3-year term.

  1. Nominations:  Any member may volunteer or nominate somebody for Trustee.   Nominations may be sent to the Chair by email ( or post (Newton House, 25 Hill Road, Clevedon  BS21 7NE) . Each nomination should include the names of the nominee (who must be 16 or over), proposer and seconder.  Before nominating please confirm that the nominee is prepared to act if elected. Nominations should reach the Chair by 7th March.  Nominations will also be accepted at the AGM.
  2. Resolutions  Members may propose resolutions to put to the meeting. Resolutions must reach the Chair by 7th March. 
  3. Voting:  Paid-up Marlens members (which includes Marlens Lottery members and Friends of Clevedon Marine Lake) have a vote. Others are welcome to attend and join in the discussion.  
Join in

All members of the community are welcome. You can join this year’s AGM from the comfort of your home using Zoom. You can get Zoom on your computer, laptop, tablet or smartphone. If you haven’t used Zoom before, you will need to download it first, so please give yourself plenty of time to get to know it. You can find out how to use Zoom here.

Join Zoom Meeting

Meeting ID: 875 3698 7263
Passcode: AGM2021 

The minutes from last year’s AGM are below.

AGM Minutes, 15th March 2020


Sunday 15th March 2020 

6:30pm start 

Kindly hosted by  

Clevedon Sailing Club 

16 members of the community were present, of whom 12 were paid-up members, so the meeting was quorate. See the list at the end of these minutes. 

Joe Norman took the chair and thanked everyone for attending. Apologies: see list at end of this document.
Minutes of Previous AGM (17 March 2019): The minutes were approved by the members. 

Proposed by: Linda Knott, Seconded by Liz Jarvis 

There were no matters arising.

Trustees Report: The Trustees Report was available at the meeting, 
Financial Report: The financial report was available at the meeting. The  Accounts had been inspected and approved by an accountant (as required by the Charity Commission) and reflect the year-end as of 31st October  2019. The current financial position (money in the bank) is lower due to planned subsequent expenditure on lake improvements including six new benches and a week’s dredging. 

The report was presented by the Treasurer, Bob Slee, and approved by the members. 

Proposed by: Bob Slee, Seconded by Linda Knott

Election of Trustees & Officers: 

Our constitution requires that one-third of the trustees retire at each AGM,  but may stand for re-election.  

Retiring: Tony Cherry 

Linda Knott 

Chris Blades (current trustee seeking re-election) 

Linda Knott had been associated with Marlens ever since it was set up by 


her husband Arthur in 2005, and took the opportunity to make a statement thanking everyone for their support and urging the need for a new generation to take Clevedon Lake forward. 

In addition to Chris Blades, three new Trustee candidates volunteered at the meeting. All four were proposed en bloc and approved by the members. 

Chris Blades 

Mike Perrott (Clevedon Canoe Club) 

Myles Podmore (Clevedon Inshore Rowing Club) 

Hilary Jenkins-Spangler (lake swimmer) 

Officer Posts 

Treasurer: Bob Slee was prepared to continue in office as honorary  Treasurer. No other nominations had been received, and Bob Slee was  approved by the members. 

Secretary: Vacant. No nominations had been received but two people had answered the recent advertisement for a paid post. 

Joe Norman had been acting as Secretary (as well as Chair of Trustees) and would continue until a replacement could be found.

Member Resolutions: No resolutions had been received.

The Trustees expressed their thanks to  

  • Viv French, Marlens’ bookkeeper, for keeping the finances in great order. Linda Knott, who is retiring as a Marlens’ Trustee, following 17 years of bringing life to the Marine Lake. 
  • Marlens’ Saturday Cleaning group for a phenomenal job keeping the lake ship shape. 
  • The Community for its engagement with the lake – without which it couldn’t survive. 

The formal meeting closed at 7:30 pm 

This was followed by light refreshments and a question and answer session including an informal review of forthcoming activity on and around the lake. 

Lake Safety:  

It was agreed that Clevedon Sailing Club, Clevedon Canoe Club, Clevedon Marine Active and Matt Taylor (hire boats and zorbs) would liaise via What’s App to coordinate larger group sessions, to ensure all users have adequate space to run tuition safely, especially when the sailing rope is in use. Changes to be communicated to Viv French to update the lake calendar on the web site. 

2020 Events, subject to Covid-19 guidelines: (some cancellations probable) Bristol Old Vic tour – 2nd April 

  • Lake Day – 9th May, 1pm start this year because of overtopping tides in the morning. Lake Day have-a-go sessions confirmed by Clevedon Canoe  Club, Clevedon Sailing Club and Clevedon Coastal Rowing plus lakeside activities. Volunteer rota to be compiled by Lorrie Parnell.  
  • Arnos Vale morbid curiosity tour – 10th June 
  • Marlens’ Musical Extravaganza – 2nd October. Volunteers needed – 8 fire marshals and a Master of Ceremonies. 
  • Light up The Lake – 5th December. Light up The Lake – Marshals required to manage access points. For safety reasons the lakeside will be cordoned off, and entry in/onto the water by invitation only. Spectators welcome as  before on the upper promenade  
  • Winterfest – 30th January 2021 tbc

The clearance programme in March was very successful, increasing the lake depth to 3ft around the promenade perimeter. Possible conveyor systems to be considered and costed for future dredging, to speed up the process. 

The small original penstock broke during the drain-down for dredging. This was not replaced in 2015, during the renovation. North Somerset Council is obtaining a quote from Dyer and Butler to replace it, possibly during the next dredging drain down planned for October 2020.  

The slipway at the splash pool end has a sharp concrete lip where the tide scours away the gravel bottom. Marlens to assess the best solution to eliminate injuries from the angular finish to the slipway (for example replace rubber edging, concrete inclined extension), possibly implemented during Oct 20 drain down. 

See whether some space could be reserved on the NSC event boards on Salthouse  Field, to advertise Clevedon and lake events. 

16 Present, including 12 paid-up members (Lottery or Friend) and 5 trustees: 

Marlens  Lottery 

Ken Ellis X Jenny Ellis X 

Friend of CML 


Joe Norman X X Maggie Norman X 

Rowena Hastings X 

Chris Cooper Clevedon Sailing Club. X Liz Jarvis X 

Linda Knott X X Mike Perrott Clevedon Canoe Club. X 

Lorrie Parnell X 

Matt Taylor 

Kate Gay X Chris Blades X X Alison Holland Clevedon Marine Active.  

Stephen Holland Clevedon Marine Active.  

Bob Slee X X X  11 Apologies 

Michael Batchelor Barry Cherokoff Viv French Tony Cherry John Merritt Bryn Hatch Paul Edwards Stephanie Collins Carolyn Waite Marilyn Edwards Rowan Clarke 

Drain down: Lake closed

The Marine Lake will be emptied of water from Friday 19th March. It will refill at high tide on Sunday 28th March.

We empty the lake twice a year to remove the silt and mud from the lake floor. The huge tides in the Bristol Channel cause the silt to never settle, and every time the tide tops over the lake wall it dumps the silt into the lake. Over time, the silt would cause the lake to become shallower and shallower, and it would also collect bacteria that would reduce the quality of the water.

By emptying the lake twice a year, we can hire a digger to remove some of the silt. It also gives us the chance to carry out essential repairs and maintenance. We have plans to:

  • Add hooks so that clubs and coaches can rope off small areas for training and lessons
  • Improve disabled access
  • Fix a leak in the sea wall
  • Clean seaweed off the slipway and steps
  • Add steps at the shallow end of the lake for better access
Donate now

The licence to put the silt and mud back in the sea is very costly, as is the hire of the digger. If you enjoy using the lake, please consider donating.

You can donate your time, too.  There will be a clean-up working party meeting by the shuttered store near the amusement arcade at 9am on Saturday 27th March. Please do come along and help.

See the calendar for more info about what’s going on at Clevedon Marine Lake.

New Year dip cancelled

It’s been a Clevedon tradition for years, but the coronavirus pandemic will stop this year’s Boxing Day and New Year’s Day dip.

It’s important that we keep everyone safe by sticking to government guidelines around social distancing and mass gatherings. But it’s also important to bear in mind that getting into cold water can be very dangerous and we must not put an extra strain on the emergency services.

“The New Year dip is magical and it brings lots of people to the lake who don’t swim throughout the year, plus lots of people with hangovers,” says Rowan Clarke, Outdoor Swimming Coach. “This increases the chance of a medical emergency, which just isn’t fair to put on the frontline health workers this year.”

For Marlens, the charity that runs the lake, this means the loss of donations, so please consider donating anyway.

We look forward to starting off 2022 with a New Year’s Day dip. Until then, keep safe and well.

Don’t swim until you’ve done this!

You wouldn’t go caving, climbing or scuba diving without a lesson or guide, would you? Well, cold water swimming is also an extreme sport and we want everyone to learn to do it safely.

With so many mental and physical health benefits, it’s no wonder so many people have started swimming outdoors in 2020. Here at Clevedon Marine Lake, we’ve seen a huge number of new cold water swimmers. But, with lockdown stopping groups from meeting, lots of new swimmers are missing out on learning how to swim safely in winter temperatures.

Now, there is help at hand from NOWCA (National Open Water Coaching Association). This free course will help you learn how to make the most of your cold water swims. It takes just 20 mins and you can do it online.

We love seeing so many happy faces at the lake. We urge you to do this short course so that you can get maximum benefits with minimum risk.