Guidance

River Thames: current river conditions

The current conditions affecting boaters on the River Thames and what the warnings mean.

From:
Environment Agency
Published
12 February 2020
Last updated
1314 March 2025 — See all updates

Before you take your boat out on the River Thames, you should find out the current river conditions and make sure you understand what they mean. You should also check if there are any closures or restrictions in your area.

Current river conditions: updated 1314 March 2025

We update our information about the river conditions and strong stream warnings once a day by 11am. You should also check the warning boards displayed at lock sites or talk to lock staff if you are using your boat on the river.

Lechlade to Oxford

Reach Current conditions
Upstream of St John’s Lock Yellow caution: stream decreasing
St John’s Lock to Buscot Lock Yellow caution: stream decreasing
Buscot Lock to Grafton Lock Yellow caution: stream decreasing
Grafton Lock to Radcot Lock Yellow caution: stream decreasing
Radcot Lock to Rushey Lock Yellow caution: stream decreasing
Rushey Lock to Shifford Lock Yellow caution: stream decreasing
Shifford Lock to Northmoor Lock Yellow caution: stream decreasing
Northmoor Lock to Pinkhill Lock Yellow caution: stream decreasing
Pinkhill Lock to Eynsham Lock Yellow caution: stream decreasing
Eynsham Lock to Kings Lock Yellow caution: stream decreasing
Kings Lock to Godstow Lock Yellow caution: stream decreasing
Godstow Lock to Osney Lock Yellow caution: stream decreasing
Osney Lock to Iffley Lock No stream warning

Oxford to Henley

Reach Current conditions
Iffley Lock to Sandford Lock Yellow caution: stream decreasing
Sandford Lock to Abingdon Lock Yellow caution: stream decreasing
Abingdon Lock to Culham Lock No stream warning
Culham Lock to Clifton Lock Yellow caution: stream decreasing
Clifton Lock to Days Lock No stream warning
Days Lock to Benson Lock No stream warning
Benson Lock to Cleeve Lock No stream warning
Cleeve Lock to Goring Lock No stream warning
Goring Lock to Whitchurch Lock No stream warning
Whitchurch Lock to Mapledurham Lock No stream warning
Mapledurham Lock to Caversham Lock Yellow caution: stream decreasing
Upstream of Blakes Lock Red caution: strong stream
Caversham Lock to Sonning Lock Yellow caution: stream decreasing
Sonning Lock to Shiplake Lock Yellow caution: stream decreasing
Shiplake Lock to Marsh Lock Yellow caution: stream decreasing
Marsh Lock to Hambleden Lock Yellow caution: stream decreasing

Henley to Teddington

Reach Current conditions
Hambleden Lock to Hurley Lock Yellow caution: stream decreasing
Hurley Lock to Temple Lock Yellow caution: stream decreasing
Temple Lock to Marlow Lock Red caution: strong stream
Marlow Lock to Cookham Lock Yellow caution: stream decreasing
Cookham Lock to Boulters Lock Yellow caution: stream decreasing
Boulters Lock to Bray Lock Yellow caution: stream decreasing
Bray Lock to Boveney Lock Yellow caution: stream decreasing
Boveney Lock to Romney Lock No stream warning
Romney Lock to Old Windsor Lock No stream warning
Old Windsor Lock to Bell Weir Lock No stream warning
Bell Weir Lock to Penton Hook Lock Yellow caution: stream decreasing
Penton Hook Lock to Chertsey Lock Yellow caution: stream decreasing
Chertsey Lock to Shepperton Lock Yellow caution: stream decreasing
Shepperton Lock to Sunbury Lock Yellow caution: stream decreasing
Sunbury Lock to Molesey Lock No stream warning
Molesey Lock to Teddington Lock No stream warning

What the warnings mean

Any river activity poses a greater risk when there are strong currents, high river levels or cold weather conditions. River flows can increase even during the summer months. Never assume that sunny weather means the conditions are not hazardous.

The Environment Agency may display warning boards at locks to inform river users of the conditions. Read the explanations of what these mean for you. Do not take risks and never underestimate the power of the river.

Strong stream warning

A red sign with white text reading 'Caution: Strong stream'.

Strong stream warning board

When these red boards are displayed, the Environment Agency advises users of all boats not to navigate. The strong flows make it difficult and dangerous.

People in hire boats arriving at a lock where these boards are displayed should stop immediately. Contact your hire boat operator to ask for instructions.

Stream increasing warning

A yellow sign with black text reading 'Caution: Stream increasing'.

Stream increasing warning board

When these yellow boards are displayed, the Environment Agency advises:

  • users of all unpowered boats not to navigate
  • users of powered boats to find a safe mooring

River flows are likely to strengthen, and strong stream boards could be displayed very soon and without further warning.

Stream decreasing warning

A yellow sign with black text reading 'Caution: Stream decreasing'.

Stream decreasing warning board

When these yellow boards are displayed, the Environment Agency advises:

  • users of all unpowered boats not to navigate
  • users of powered boats to navigate with caution

Using navigation marks

When travelling upstream, keep red navigation buoys to your left and green navigation buoys to your right.

When travelling downstream, keep red buoys to your right and green buoys to your left.

You may pass single yellow marker buoys on either side.

In all cases, keep well clear of navigation buoys. Be aware of possible shoals on the inside of river bends.

Dealing with changing river conditions

If you find yourself in conditions where the Environment Agency advises you to stop navigating, please take the advice and stop. Even the most experienced boater can be caught out, so think about those who could be put in danger if they have to help you.

You may find the following measures helpful. Not all conditions will be serious enough to need all the suggested measures.

Moor your boat in a safe place, preferably in a marina or at a recognised mooring. Limited space may be available at some locks. Moor against high banks if you can.

Ensure your mooring lines are fastened to secure fixings such as bollards, rings or even trees. Put out extra lines for more security and allow enough slack for a further rise in river levels. Do not rely on your own mooring pins or stakes, as they might not hold.

If possible, put extra fendering (such as scaffold poles or strong timber posts) between your boat and the bank side. This may prevent your boat drifting onto the river bank and becoming caught up when levels drop.

Make sure you have a safe exit ashore from your boat. If not, consider returning home or finding alternative accommodation until conditions improve.

If you are not able to vacate your boat safely and are running low on essential supplies or have other safety concerns, treat this as an emergency. Dial 999 to ask for evacuation.

Those in hire boats should stop immediately if you are advised to stop navigating. Contact your hire boat operator and follow their instructions.

Please remember your life is more important than your boat.

The Environment Agency does not provide emergency services. We are not able to carry out search and rescue, or provide supplies to stranded boats.

Contact the Environment Agency

General enquiries

National Customer Contact Centre
PO Box 544
Rotherham
S60 1BY

Email enquiries@environment-agency.gov.uk

Telephone 03708 506 506

Telephone from outside the UK (Monday to Friday, 8am to 6pm GMT) +44 (0) 114 282 5312

Monday to Friday, 8am to 6pm.

Environment incident hotline

Telephone (24 hour service) 0800 80 70 60

Updates to this page

Published 12 February 2020
Last updated 1314 March 2025 + show all updates

    3. River Thames current conditions updated for Thursday 13 March 2025. No stream warning changes.

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