Which Side of the River? Turning Local Knowledge Into Race Strategy

Learning to Race — From First Start to Better Results

The shortest route up a river is frequently not the fastest route.

Two boats round a mark together. One takes a direct route towards the next mark. The other moves towards the bank, makes an apparently unnecessary tack and sails further.

A few minutes later, the boat that travelled further is ahead.

Was it better sail trim? A faster boat? A fortunate gust?

Possibly. But on a river, the answer may lie in something more interesting: one crew recognised where the useful wind and water were, while the other simply aimed at the destination.

At Upper Thames Sailing Club, trees, buildings, bends, stream and other boats all influence the route. The challenge is to turn those observations into decisions before the opportunity has passed.

For me, learning to race Champagne is partly about learning the boat. It is also about learning to see the river differently.

The important question becomes:

Which route will get us to the next mark soonest—and what evidence supports that choice?

1. The River Is a Changing Racecourse

On a diagram, a sailing course looks reassuringly tidy: a start line, some marks and straight lines between them.

The river adds another layer.

One stretch may have relatively open wind. Further along, trees interrupt it. A building may create a patch of disturbed air. A bend changes the relationship between the river and the wind. Meanwhile, the strength and direction of the stream vary across the available water.

Upper Thames Sailing Club describes its sailing reach as extending between Bourne End and the islands below Marlow Lock. That setting provides plenty of opportunity to experience these interacting effects.

However, local knowledge should be more useful than a collection of instructions such as:

“Always go towards that bank.”

A better version is:

“That bank can work when the wind comes from this direction, provided there is still enough breeze beneath the trees.”

The first is a habit. The second is a strategy you can test.

Good local knowledge explains when a route works, why it works and when to abandon it.

2. Read the Windward Shore Before Choosing Your Side

Before looking for the best patch of water, look at what the wind has travelled over to reach it.

Has it crossed open ground? A line of mature trees? Houses? A gap between buildings?

Trees and buildings can reduce wind speed and create turbulence downwind. Their effects depend on their height, shape, spacing and the wind direction. The disturbed area does not necessarily end at the shoreline.

That produces a familiar river-sailing trap: the boat moves towards apparently sheltered water to escape the current, then loses the wind needed to make progress.

There is another complication. The bank closest to you is not necessarily the bank causing the problem. If the wind crosses the river, obstructions on the opposite shore may affect the air reaching your sails.

What to watch

Look for agreement between several clues:

• Ripples fading as they approach a particular stretch.

• Boats repeatedly slowing in the same area.

• Sails losing their shape or telltales becoming unsettled.

• Tree movement that differs from what you feel aboard.

• Better progress by boats sailing slightly further offshore.

One boat slowing could be poor handling. Several boats slowing in the same place are stronger evidence.

Choose your lane by the wind reaching the boat, rather than by how inviting the bank looks.

3. Pressure Can Matter More Than Pointing

In racing conversation, “pressure” usually means stronger wind.

When the breeze is light and uneven, a patch of useful pressure can be more valuable than a small improvement in sailing angle.

Imagine two boats beating towards a mark.

Boat A points a little higher but repeatedly enters weak, disturbed air.

Boat B sails a slightly less direct heading while keeping its sails drawing and its hull moving.

Boat B may arrive first because its average progress is better.

This does not mean sailing towards every gust. A gust has to be reachable, useful and worth the distance required to intercept it.

Ask:

1. Is that darker patch actually wind?

2. Is it moving towards us or away from us?

3. Can we reach it before it passes?

4. Will reaching it leave us with a useful route afterwards?

Darker water can also result from reflections, current or viewing angle. Treat a visible gust line as a clue, then check the response of boats within it.

A useful crew call

“More wind on the other side” is an observation.

“More wind approaching from the other side; one short tack could put us into it before the trees” is a possible plan.

The second gives the helm something to assess.

4. The Bank Can Save Current—and Cost the Race

Our earlier article, The Current Changes Everything, explored the difference between speed through the water and progress over the ground.

Choosing a side means applying that distinction.

Against the stream, a lane of weaker current can help. But a bank route must also provide enough wind, sufficient depth and room to manoeuvre.

Consider these simplified figures. They describe movement along an upstream leg, rather than total boat speed:

Lane	Upstream component through the water	Opposing stream	Net upstream progress
Open water	1.8 knots	0.7 knots	1.1 knots
Bank with useful wind	1.5 knots	0.2 knots	1.3 knots
Bank in a wind shadow	0.8 knots	0.2 knots	0.6 knots

The bank wins in the second situation and loses badly in the third.

For this aligned example:

Upstream progress = upstream component through the water - opposing current

The figures are illustrative, not measurements from a Champagne race.

The practical lesson is straightforward:

Weaker current helps only while you retain enough useful sailing speed.

Also remember that upstream is not necessarily upwind. An upstream leg might be a beat, reach or run, depending on the wind.

5. Downstream, Change the Question

When sailing downstream, stronger favourable current may become an advantage.

The route you avoided on the upstream leg could be worth seeking on the return.

But stronger stream does not automatically justify a long diversion. You still have to consider the distance, wind, traffic and cost of manoeuvres.

For a simplified route comparison:

Time taken = distance travelled / average speed over the ground

A 300-metre route averaging 1.5 metres per second takes 200 seconds.

A 360-metre route averaging 1.7 metres per second takes about 212 seconds.

The second route is faster over the ground but takes longer because the extra distance outweighs the gain.

There is a useful racing habit here: reassess the river after rounding the mark. The conditions that favoured one lane in one direction may favour another on the return.

6. Bends Change the Problem Ahead

A river bend changes the orientation of the sailing space relative to the wind.

Without any change in the broader wind direction, the next section may offer a different sailing angle. It may also expose the boat to different trees, buildings and gaps along the shore.

Current adds another complication. Flow often becomes stronger towards the outside of a bend, but depth, islands, structures and local river shape can alter the pattern.

“Inside slow, outside fast” is a starting hypothesis, not a reliable map.

Before reaching the bend, look beyond it:

• Which shore will be upwind of the next section?

• Where does the usable breeze appear to begin?

• Are boats ahead gaining or losing speed?

• Will our present lane give us room to turn or tack?

• Where will the stream carry us during the transition?

The best position approaching a bend may be the one that provides a clean exit, rather than the one that saves a few metres on entry.

Sail the next piece of river before you arrive in it.

7. Champagne: What the Tall Rig Can—and Cannot—Tell Us

Aboard Champagne, the height of the rig adds another dimension to reading the river.

An A-Rater can encounter air higher above the water than a smaller dinghy. That can sometimes help when the lower air is obstructed, but trees can be tall too, and disturbed airflow can affect a substantial part of the sail plan.

A tall mast is an opportunity to find useful wind. It is not immunity from wind shadows.

It also means that a nearby dinghy is an imperfect comparison. Its behaviour is useful evidence, but it may not be experiencing exactly the same air.

The questions aboard Champagne become:

• Is the upper sail still working while the lower sail struggles?

• Are we retaining speed through this patch?

• Is the stream carrying us towards a difficult position?

• Can we leave this lane before losing the room to tack?

My own published account of bringing Champagne into the Queen’s Cup story records the help Adrian Hart and Matthew from Scamp gave with setting the sails and adjusting the boom before our first sail. That is a useful reminder of how much there is to learn from people who know these boats.

The next step is to connect that boat-handling knowledge with the water ahead.

A well-set boat still needs somewhere useful to sail.

8. Three Racing Decisions to Practise Aboard Champagne

These are worked scenarios based on river-racing conditions, rather than accounts of particular recorded races.

Scenario A: The Tempting Upstream Bank

We are making steady progress against the stream. Near the bank, the water appears quieter, but trees stand upwind of the lane.

A rival moves close in and initially gains. Further along, its sails soften and its progress slows.

The useful response is to separate two effects: the bank is offering less current, but the next section appears to offer less wind.

A possible plan is to use the weaker stream while retaining a route back into clearer air before the shaded section.

The mistake would be to continue towards the bank simply because the first part worked.

The best lane can end halfway along a leg.

Scenario B: A Gust Approaches Across the River

We see rippled water approaching from the opposite side. A boat within it accelerates.

Crossing may help, but the crossing itself has a cost. It may involve stronger stream, disturbed air from another boat or an awkward arrival near the bank.

The decision should consider the whole sequence:

Reach the gust, use it, then leave it in a useful position.

If the gust is brief or moving away, maintaining our current lane may be better.

The mistake would be to chase yesterday’s opportunity—the patch that looked promising several moments ago.

Scenario C: The Fast Lane Has No Exit

There is useful wind and weaker stream near the bank. For the moment, everything looks favourable.

However, another boat is approaching, the bank is converging and the next tack will need space.

Continuing for a few extra seconds may surrender the ability to manoeuvre when we want to.

A slightly earlier tack could preserve speed and choice.

The mistake would be to judge the lane solely by its present benefit.

A lane is only as useful as your ability to leave it.

9. Use Other Boats as Moving Evidence

The fleet can help reveal the river.

Watch boats on different routes and compare their progress against fixed bank features. A boat may look lively through the water while making disappointing progress towards the mark.

The most useful comparisons are between similar boats in similar circumstances.

Ask:

• Are they travelling at a comparable sailing angle?

• Are their sails drawing?

• Have they just tacked?

• Are they in another boat’s wind shadow?

• Does the gain persist?

One boat gaining once is interesting. Several boats gaining repeatedly in the same lane are more persuasive.

Avoid following a familiar local sailor without understanding the reason. They may be responding to a short-lived opportunity, preparing for another boat or making a mistake themselves.

Copy the reasoning when you can identify it. Keep checking the result.

10. Turn Local Knowledge Into a Testable Plan

A useful plan can fit into three short statements:

Observation: The bank has weaker stream, but boats lose wind beside the trees.

Plan: Use the bank lane through the open section, then move out before the shelter.

Change trigger: Leave earlier if our sails stop drawing or boats outside start gaining.

That final statement matters. It prevents a sensible idea becoming an expensive commitment.

It also makes communication aboard clearer. Everyone knows what we are trying to achieve and what would make us reconsider.

Before the start, agree the likely advantage, the main risk and the point at which the decision needs reviewing.

You do not need a prediction for every metre of river. You need a reason for the next choice.

11. Build Your Own River Notebook

After racing, record a few observations while they are fresh.

Record	Useful detail
Wind direction	Where the wind came from relative to the reach
Wind strength	Whether pressure was steady or patchy
Stream	Observed differences between lanes
Location	A recognisable bank feature or section
Boat response	Speed retained, lost or recovered
Interpretation	Why the route appeared to help or hurt
Confidence	One observation or a repeated pattern

“The bank was good” is too vague.

“The bank lane helped against the stream until the wind faded beside the trees” is something you can investigate next time.

For Champagne, photographs and video can support that process. They may show when the sails lost shape, when another boat entered the same patch or how long a tack took.

Footage cannot measure unseen wind or current by itself, but it can help us ask better questions.

12. Five Questions Before Choosing a Side

During the race, reduce the detail to a manageable check:

1. Wind: Where is the most useful breeze?

2. Water: What is the stream doing in each lane?

3. Distance: Will the advantage repay the diversion?

4. Room: Can we tack, keep clear and leave the lane?

5. Evidence: What tells us the plan is still working?

Room includes depth, overhanging branches, moored boats and other river users. A promising racing route still has to be navigable and leave room to meet your obligations.

The aim is not to make the river predictable. It is to become quicker at recognising what matters.

Conclusion: Learn the Reason Behind the Route

The attraction of river racing is that the course keeps asking questions.

A bank offers shelter from the stream, then takes away the wind. A gust rewards a crossing, then moves on. A bend changes the next decision before the previous one is finished.

For me, that is part of the pleasure of sailing Champagne. There is the satisfaction of handling the boat better, alongside the quieter challenge of understanding why one patch of river works and another does not.

Local knowledge grows when we observe, form an explanation and test it again.

Next time you race, choose one section to study. Watch the wind, compare the lanes and notice where the boats actually gain. Afterwards, write down the reason you think it happened.

The shortest route is easy to draw. The fastest route has to be read from the river.

Follow Champagne’s sailing and racing journey at pmrsailing.uk.

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