Everything you need to know about SUP - or kayaking - safety on the Thames
This is a slightly updated version of an article we originally wrote in 2020.
Sun shining, no wind, beautiful day – perfect conditions to go paddleboarding on the Thames…. But wait, is there anything else to consider?
There certainly is!
So read on if you want to understand more about safety on the river, particularly during the colder months. If you want to know what kit to pack for a safe paddle trip on the Thames then check out our paddleboarding equipment list.
This article covers the key things our instructors take into account when they decide whether it’s safe or not to go out on the river, and shares some of the apps and resources we use (full list at end of article).
We call it a risk assessment, and every day these factors determine whether a paddleboard lesson or trip goes ahead, is postponed or even cancelled. The factors we look at are:
Weather
Tides
River Flow
Water Quality
River Traffic
Route Planning
Links to Resources
1.Weather – the first thing we do is check the likelihood of rain and thunderstorms, the air and water temperature, and the wind speed and direction.
We use the Apple Weather or Met Office apps for very local weather, Weather Pro for week ahead forecasts and Windy for wind conditions. The BBC weather is generally not nearly accurate or localised for us.
Let’s deal with the key factors one at a time:
Rain / Thunderstorms - It’s actually fun and rather beautiful paddling in the rain, but highly dangerous in thunderstorms where there is a risk of lightning. So definitely check thunderstorm and lightning risk and never go out on the water if there’s any likelihood. We use a Lightning Radar app for localised info on storms.
For thunderstorms, the 30-30 rule applies: Get off the water if the flash to bang time (the time between seeing lightning and hearing the thunder) is less than 30 seconds. Stay off the water until at least 30 minutes after the last clap of thunder.
Fog, although rare, is also worth avoiding – as visibility on the water is critical for safety. But a little mist adds atmosphere and is fine…
Air temperature – if it’s cold, wrap up warm, remembering a hat and gloves. Carry a drybag for extra layers, or for the layers you remove once you warm up. When you are standing up on a paddleboard you’re exposed to any wind, so remember the effects of wind chill.
Water temperature – the water in the Thames is always pretty cold, averaging 12 degrees, and there’s a real risk of cold water shock even in summer (see this article on cold water shock for more info). Carry extra layers in case you take a dip, avoid cotton clothing, which is really cold when wet, even on warm days, and wear a wetsuit if water temperatures dip below 12 degrees. If you get wet, get those warm layers on quickly before your temperature drops.
Wind speed and direction – at Richmond we are fortunate that the bends in the river generally protect us from the prevailing SW wind, but as you paddle upstream towards Eel Pie island and Twickenham it can be pretty exposed. Generally winds of up to 10mph, gusting up to 20mph, are manageable, although we will paddle in the more sheltered spots in winds of 15mph, gusting to 30mph. Local knowledge is vital here! So look at a map and the wind direction before you go out, so you know what to expect. Otherwise you risk going out and not being able to get back to your start point…. We use the excellent Windy app for this.
2.Tide
Understanding the tide on the Thames is critical for your safety and trip planning.
The Thames is tidal up to Teddington Lock, with two High and Low Tides per day. At Richmond, we are fortunate in that the weir gates at Richmond Lock are lowered to maintain an upstream river depth of 1.7m from two hours before High Tide to two hours after High Tide. This creates an eight-hour Half-Tide window where river conditions are generally safe, with low currents (unless there is high fluvial flow, about which more later). During this time paddle trips can generally be run in either direction on the river between Richmond Lock and Teddington. Below Richmond Lock the river is always tidal, and extreme care needs to be taken during the mid-tide period when flows are strongest.
All our session times at Richmond are determined by the tides, and we schedule these using tide tables provided by the Port of London Authority who control the river up to Teddington
We also use apps like Tides Planner for tides on the day, Tides Near Me for planning up to a week ahead, and Willy Weather for longer term tide planning.
The key thing to consider is whether your paddle trip will be affected by the tides. If paddling near Richmond at half-tide, make sure you’re off the water before Richmond Lock weir gates open as you risk not being able to paddle home against the tide. Similarly, if you go on the water at High Tide, the tide will very soon start to go out, or Ebb, with very fast flows downstream. These can be very difficult to paddle against, with flow rates of up to 8 knots (10mph) which is really fast – you run a real risk of entanglement in moored boats, low branches and pontoons if you fall in or are swept towards them. If in doubt restrict your paddling to half-tide, or come on one of our Paddle Skills and River Safety Classes to learn more about river safety.
The other thing we consider is Spring Tides, which occur every 14 days around the full Moon and new Moon. This leads to very high tides, often covering the towpath at Richmond – and a far greater volume of water moving on the tides, with higher flow rates and increased level of risk. Spring tides are also significantly stronger than neap tides, and this will affect your ability to paddle against the current.
Also note that very occasionally, when there is high river flow, and tidal surges and big spring tides are forecast, the Thames Barrier may be closed to prevent flooding, often with minimal notice. This will mean that the incoming High Tide only reaches half normal height before starting to ebb, and therefore cannot be relied on to assist you going upstream. We check this on X.
3.Fluvial flow – or land water
This is a key consideration before you go paddling. If there has been heavy rain upriver from Richmond, the flow from land water, known as fluvial flow, can increase dramatically. At high flow levels, even at half-tide, it can be too dangerous to go out on the water. Flow is measured in cubic metres per second, and we take measurements from the Environment Agency’s river gauges at Kingston, the nearest accurate gauge. This data is also available on X.
We also look at the PLA’s website and app for their Ebb Tide Flag Warnings – which warn of dangers from flow levels on the Ebb Tide:
· Red: Danger, very strong fluvial flow, no paddling on Ebb Tide
· Yellow: Caution, strong fluvial flow, only experienced paddlers exercising caution
· Green: Average fluvial flow, safe conditions
· Black: Low fluvial flow, lower than predicted tides possible, safe conditions
·
The Environment Agency have a similar system for the river upstream of Teddington
Flow levels below 40 cu.m/sec make for easy paddling. In summer the flow rate is typically around 10 cu.m/sec, and is barely noticeable. Over 80 becomes difficult, and over 120 potentially dangerous and very difficult to paddle against. During the winter and spring we often see flow levels of 300 -400 cu.m/sec – a raging torrent, and definitely not safe for paddling! Remember also the effect of tide on river flow - an incoming tide may neutralise the flow but an outgoing ebb tide will exacerbate it and hugely increase the flow rate and level of risk.
4.Water Quality
Generally the water quality of the Thames at Richmond and above is really good, as evidenced by the huge amount of wildlife – from herons to fish to seals!
But every now and then, after very heavy rain, there can be a sewage discharge from Mogden Sewage Works at Isleworth (and other locations downstream such as Hammersmith). Definitely time to avoid paddling until a couple of tides have cleaned the river up. We check this here.
Once the Tideway Super Sewer opens in 2025, sewage in the Thames will - we hope - be a thing of the past. We can’t wait!
5.River Traffic
Remember always to paddle on the right, or starboard, side of the river - whichever way you are facing. This means you will pass oncoming river traffic port to port, or left side to left side. This is based on the The International Regulations for Preventing Collisions at Sea (Colregs), the rules aimed at preventing collisions on the water.
Before we go paddling we check for events and any traffic that may affect us. On summer weekends there is always plenty to think about – hired rowing boats, pilot gigs, rowing sculls and eights, canoes, gin palaces and the passenger boats operated by Turk’s Launches and Colliers (Remember they can’t manoeuvre easily and have no brakes!). We need to ensure that we keep out of the way, stick to starboard (the right-hand side of the river whichever way you are paddling) and maintain a good lookout. The larger boats will sound their horns to indicate their intentions - a long blast probably means get out of the way, but the shorter duration series of blasts mean they are turning around - see guide here.
The PLA maintain an events calendar which advises us of regattas or races on the river – anything from sailing races to rowing and kayaking events. The same info is available on their app.
In some cases these can result in a river closure, where no paddling is allowed. For example, the Oxford and Cambridge Boat Race always involves a river closure between Putney and Chiswick, and the Great River Race closes the Thames from Central London up to Eel Pie Island. We check the Notices to Mariners from the PLA for this – they send us an email but you can look here: http://www.pla.co.uk/Safety/Regulations-and-Guidance/Notices-to-Mariners/Notices-to-Mariners
For river closure information above Teddington Lock, we check the Environment Agency website here.
6.Route planning
Finally for this blog post, we look at route planning. Before we set off we work out where we intend to paddle, what our turning point will be, any stopping points (the White Swan at Twickenham , The Anglers at Teddington Lock and the London Apprentice in Isleworth are favourites) and what hazards we expect en-route. And we have a back-up plan if weather or traffic conditions in a certain part of the river makes it too difficult to paddle there.
We also make sure we have a good understanding of where we can exit the river if we need to – our access and egress points. There are plenty of steps and slipways along the Thames, but we also consider which of these allow vehicular access should anyone need a taxi home, or, worst case, should an ambulance be required.
On longer trips (further up or down the Thames, or on the coast) we use a tracking app to let our friends and family know where we’re going and what our expected finish time will be. They get alerted and can see our position if we don’t turn up on time. There are plenty of these including WhatsApp location alerts, but we like RYA Safetrx as it includes a number of other useful safety features – link at end of article.
So – plenty to think about before heading out onto the river, even on the sunniest of days. If you’d like to know more, come on one of our Paddle Skills and River Safety Classes.
In part two, we’ll be discussing the other areas of paddleboarding preparation – paddle equipment, safety kit, communications etc.
Resources
Paddling on the Tideway
The PLA’s Tideway code, updated for 2024
Weather:
Met Office Weather app
Apple Weather app
Weather Pro app:
Windy app:
My Lightning Tracker
Accuweather
Tides:
PLA tide tables: http://www.pla.co.uk/Safety/Tide-Tables
Tides Planner app:
Tides Near Me app:
Willy Weather
Thames Barrier info: https://twitter.com/AlanBarrierEA
Flow rates:
Kingston Gauge https://www.gaugemap.co.uk/#!Map/Summary/1249/1382
Kingston Gauge on X: https://twitter.com/riverlevel_1181
Environment Agency Thames river conditions: http://riverconditions.environment-agency.gov.uk/
PLA Ebb Tide Warning: on homepage of http://www.pla.co.uk/
PLA app:
Water Quality:
Sewage Map website: https://www.sewagemap.co.uk/
Thames Water Storm Discharge monitoring: https://www.thameswater.co.uk/edm-map
E-coli checker: https://www.thames-watch.uk/TestingHistory
Events and River Closures:
PLA events calendar: http://www.pla.co.uk/Events/Annual-Events-Calendar
River Closures via PLA Notices to Mariners: http://www.pla.co.uk/Safety/Regulations-and-Guidance/Notices-to-Mariners/Notices-to-Mariners
River Closures on the tidal Thames via PLA Notices to Mariners: http://www.pla.co.uk/Safety/Regulations-and-Guidance/Notices-to-Mariners/Notices-to-Mariners
River closures upstream of Teddington Lock:
Route planning:
RYA SafeTrx app:
Paddleboarding on the River Thames is a serene experience, but safety is crucial. Always check weather conditions, wear a life jacket, and stay aware of river traffic. If you're balancing studies and hobbies, managing time effectively is key—whether you're paddleboarding or looking to buy thesis online for academic support.