Notes on Sea Kayak Navigation and Tidal Planning

Author

Rich Bown

Published

April 3, 2026

Introduction

Sea kayaking is a uniquely varied sport. It offers a diverse set of rewards, from watching wildlife on a still morning to surfing huge waves in a tide race. It also presents a diverse set of challenges to the learner - from developing physical endurance to understanding the maths and geometry of navigation.

Like most things, the skills of sea kayaking are honed through practice. Getting out paddling, initially with others who have more experience, is the way to improve. However, ultimately most paddlers will want to undertake trips independently, and perhaps give something back to the sport by leading or coaching others. The skills required to plan trips and carry out the plan safely may not be acquired if paddlers have relied on experienced leaders in the past. Whilst the judgement needed to plan well will only come with time, the underpinning tidal planning and navigation skills shouldn’t present a barrier - unlike everything else, they can be learnt at home without getting wet!

The content on this site was originally written to support an introductory course in sea kayak navigation and planning at Cambridge Canoe Club - many thanks to them for asking me to do the course! Since then, I’ve developed the material to some degree, but it’s still very much a collection of notes rather than a coherent textbook. More recently, I have updated the content to fit with the British Canoeing Awarding Body modules. Hopefully I’ll be able to keep improving it over time.

I run occasional navigation courses, covering the British Canoeing navigation modules, typically during the winter months and often in the south-east of England. If you’re interested, or you might like me to run a course for your club/group there’s more information here. The e-book you’re reading is the ‘course handout’ for the course.

If you find these notes useful, perhaps you might consider buying me a (virtual) beer by clicking the link below:

British Canoeing Navigation modules

The British Canoeing Awarding Body used to offer two navigation courses for sea kayakers: the Coastal Navigation and Tidal Planning (CNTP) course and the Open Water Navigation and Tidal Planning (OWNTP) course. From 31st January 2025, these course were replaced by 5 modules. The modules are intended to be of interest to all paddlers, although most of the material is oriented towards people who paddle on the sea. These notes are primarily targeted at sea kayakers, but I hope that they will be useful to others, including the growing number of SUP paddlers undertaking more ambitious trips on the sea.

The 5 modules are:

  • Weather – how to obtain and understand forecasts, effects of weather on the environment, basic meteorology, local effects.
  • Tides – what causes the tides and how they vary. How to predict high water, low water and slack water. Estimating behavior of tidal streams and planning journeys in tidal waters.
  • Surf and Swell – understanding waves, wave forecasts and how they affect us.
  • Navigation – how to understand and use (OS) maps and nautical charts and how to find your way on the water.
  • Open water navigation – techniques for navigating further from land, including planning longer crossings.

The top-level sections of these notes each cover one of the modules. I’ve split the navigation module into two - part 1 covers some basics that you’ll need to know to start planning trips, whilst part 2 covers navigational techniques, some of which require a knowledge of tides.

Note that in many places, the material covered in these notes goes beyond that covered in the British Canoeing Awarding Body modules.

Warning

The information provided here should be treated with suspicion, as you would any information that you stumble across from an unknown source on the internet. You would be wise to check the information against more authoritative sources. I’d especially suggest:

Sea kayaking is inherently a potentially dangerous sport and conditions on the sea can change quickly and dramatically. There is no substitute for combining authoritative information (e.g. from well regarded reference books, Admiralty pilots and charts) with the ability to read and understand the conditions as they develop and the ability to make good decisions based on this understanding. This requires training, experience and good judgement. Anyone looking to acquire this is advised to join a good sea kayaking club and spend time with experienced sea kayak coaches. Decisions on whether and where to go sea kayaking, and any consequences arising from that, remain yours and yours alone.

Layout reference

These notes were created using Quarto and are typeset to pdf using Typst.

The notes use some formatting to help you understand what’s what, and to break up the text a little.

Highlight:

The highlight is used to emphasize important information.

Examples:

Many topics are best covered by worked examples - these are presented throughout the notes. Examples are shown in shaded boxes like this one.

Extra info:

The main page explanations are designed to include everything you need to know. However, some readers will be interested in extra background information, this is included in boxes like this one.

Trip planning

These notes cover a lot of information. I’m often asked if there’s a simple process to use this information to plan trips. The answer is probably that you’ll need to develop experience relating the theory to real world conditions and matching the environment to the needs of your group. Most experienced sea kayakers don’t follow a process or use a worksheet and will adapt their approach to the demands of the day.

I appreciate that this isn’t very useful for less experienced paddlers, so here’s an attempt to outline a process that might help you get started…

I think of trip planning as two distinct tasks:

  1. Deciding where to go. This is often the hard bit. Given the weather, wave and tidal conditions and the ability and aspirations of the group, what trip options do we have and which should we choose? I find that this is best done by studying a large-scale map covering the whole area, ideally with get ins marked. If I’m visiting a new area, I’ll often print off a simple outline of the coastline and mark on get-ins and information on possible trips from a guidebook to help me think this through.

  2. Planning the paddle. Having selected a paddle, I can now start more detailed planning. How will the topography of the coastline interact with wind, waves and tide. Where will we be at what times of the day? What strategies will I need to use to navigate? What are the main hazards and crux points and how will we deal with them. I find this planning much easier if I draw a sketch map of the coastline I’m paddling, on which I can mark wind and wave directions and tidal stream timings. Sometimes the plan simply doesn’t work out, in which case I need to go back to step 1.

Here’s a diagram showing a little more detail on the process:

Looking at each step in a bit more detail (some of the terms and ideas below might not make sense until you’ve read the rest of these notes):

Planning for wind/waves

Do we need to hide from the wind / waves, or start downwind? What options does that permit?

  • Obtain forecasts - e.g. www.windy.com / www.windfinder.com / www.surfline.com / shipping forecast

  • Check wind strength and wave size. Is the wind light enough (e.g. F1) that we can ignore it? Is it strong enough (e.g. F4 or more) that we need to hide from it behind land? If not, it’s probably still sensible to plan a paddle that starts by paddling upwind, so that the wind is behind us at the end of the day.

  • Find wave height and period. Do we need to hide from the waves - where will the fetch be less? Are the waves suitable for rockhopping? For surfing What direction will the waves be coming from - will they make it hard to paddle?

  • Assuming we need to consider wind / waves, use an overview map of the area to identify coastlines that we might be able to paddle on and access points that allow us to start upwind. This should give us a short-list of options.

Planning for tide

Does the tide limit our options in this area? When is HW/LW, what is the general tidal flow picture (flow atlas)?

Obtain HW/LW times for a reference port - from almanac or (e.g.) easytide.admiralty.co.uk . Remember to correct for BST if applicable. Use the HW times to annotate a flow atlas with the times for the day.

Are there any tidal effects (height of tide, tidal streams) to worry about for the areas in our short list? Might we want:

  • Tidal flow behind us to make the paddle easier?

  • To avoid wind against tide effects?

  • To arrive at salient points at slack tide for more benign conditions?

  • Tide turning at our turnaround point?

  • Fast tides for playing?

  • High water for easier access or to navigate shallow channels? Or low water to explore drying reefs?

Planning for logistics

How far do we want to go? What access points are available?

There are typically many factors to consider - e.g: access/egress points, distance to carry the boats, transport, cafes, group aspirations, likely group paddling speed and endurance.

Selecting a trip

What options are sensible? Which one is best?

Are there any other limits to our options or hazards to consider - e.g. other water users, danger areas, logistics, lack of escape routes?

It’s obviously critical that the weather conditions are within the skills of the group to handle. If the conditions are not right for you or those you paddle with, then do not get on the water. To avoid disappointment, it is sensible to have a fallback plan in mind, especially if people have traveled a long way.

We should now have a list of options that are safe and practical. As a group, we can discuss which we’d prefer to do.

Local wind / wave / weather effects

How will the waves / waves interact with topography/tide? Other weather considerations?

Confirm wind and waves for the area. How will they change through the day? How do we expect the shape of the coastline to interact with wind and waves?

For wind consider:

  • How much shelter the coastline will offer - how high are the cliffs?

  • Will valleys funnel wind?

  • Do we expect a sea breeze / stronger winds in the afternoon

For waves consider:

  • Waves get steeper and may break in shallow water

  • Waves will refract into shallower water, concentrating power onto headlands

  • Waves will diffract around obstacles - entering areas that appear sheltered, with less height

  • Waves reflecting off cliffs form chapatis and confused seas

  • Surf depends on wave height / period and beach steepness

Other possible weather considerations include:

  • Will visibility be reduced? Can we navigate competently despite this?

  • Any possibility of thunderstorms?

  • Will temperature / wind / precipitation chill the group? Are they dressed appropriately?

Tidal gates

Where are the tidal gates and what times do they turn? Can we use the tide to our advantage?

  • Find reference port used in the guidebook / pilot, and look up tide times, correcting for BST if required.

  • Calculate local high and low water using high water constant.

  • Calculate slack water times using data from guidebook / pilot.

  • Draw a sketch map with the key information on, decide on trip timings.

  • Consider interactions of tidal streams with wind and/or waves

Timings, navigation strategies

Work out trip timings. Consider navigational strategy: handrailing -> bearings -> dead reckoning (+tide?)

  • Where are the put ins and take outs?

  • Where do we park and how far do we need to carry?

  • How far will we paddle?

  • What are the rough timings? Do they fit with weather and tidal changes? Are there critical places that be need to be at specific times?

  • Where will we stop for breaks and lunch?

  • What navigational strategies will we need and do we need to prepare any information? Keep things simple if possible, relying on hand-railing and passing landmarks. We might wish to note key compass bearings / distances. We may need to make specific plans for tidal crossings.

Hazards, crux and decision points

Identify hazards, crux points and decision points. How will we make the decisions, what are our fallback plans?

Do we need to consider any other factors (e.g. shipping, local rules…)?

What are the main hazards and where are the crux points of the trip (e.g. exposed sections, headlands, concentrated wind, waves or tidal stream?). Where are our key decision points to keep going or turn back? Where else can we get off if things go wrong? How will we make those decisions? Do we have fallback plans if conditions prove worse than expected? At what points do we become committed? What will we do if things go wrong at each point?

Check that the plan is sensible - if not, consider other venues.

Finish by copying key information to the map that you will carry on the water. Aim to keep your plans flexible - consider different options and be prepared to change if things don’t turn out as expected.

Checking actual conditions

It’s wise not to rely completely on the forecast. Take time when you arrive at your launch point to check that conditions you see out on the water are those that you expect. Is the wind direction about what you expect? Does the effect of the wind on the sea match what you’d expect from the Beaufort Scale descriptions? Keep an eye on the weather and the sky to see how the weather develops.