Entry to the Grand Union Canal is made by entering Brentford Creek on the Middlesex Bank about 1.5 miles below Richmond Lock. From upstream the entrance is inconspicuous but lies just below Syon Park against which there are a number of barge moorings.

Thames Lock (No 101) is the first lock, and is paired. Operating times are limited, so beware!

British Waterways now publish six-monthly guides of lock opening times on a day by day basis. They will send you one of these free of charge on request -- call their London office on 020 7286 6101

As a rough guide, locking times are as follows:

• Thames Lock is only usable for two hours either side of high water, which is approximately 1 hour after high tide at London Bridge.

• The lock is normally only staffed between 08.00 and 17.00

• Given 24 hours notice, passage may be arranged at any time between 05.00 and 22.00 (tide permitting of course!)

Thames Lock can be contacted by phone on 020 8560 1120, and you may make a "booking" by leaving details on the answering machine. It is recommended that before planning your journey you check the current situation with BW, either at Thames Lock, or at their main London office on 020 7286 6101.

Brentford Lock (No 100) is the next lock, and is also operated for you. If you can get through Thames lock, you should be able to get Brentford lock opened too.

Vital statistics for both locks Length 72'0" Width 14'3" Maximum draught 3'6"

On spring tides you should note that the headroom of Dock Road Bridge which crosses the tail of Thames Lock can be as little as 7' - you may therefore have to wait outside the lock in the creek until the tide has fallen sufficiently for your boat to clear the bridge. Since the pound above Thames Lock is partly tidal, the headroom under Brentford High Street Bridge (No 209) may also be restricted.

If you are planning to enter or leave these locks, it is strongly recommended that you do phone in advance on one of the numbers above.

For further information on planning a passage:

• Transfer passages downriver between Teddington and Brentford
• Working upriver to the Grand Union from the Lower Thames

See also The Inland Waterways Association Thames Tideway Guide

The Tideway pages are maintained by John Kennett
Comments, corrections and additions are always welcome