(19)

(11)

EP 1 723 293 A1

(12)

(43) Date of publication: 22.11.2006 Bulletin 2006/47 (21) Application number: 05717931.9 (22) Date of filing: 07.03.2005

(51) International Patent Classification (IPC):  E04H 1/12(2006.01) B63B 25/28(2006.01) (86) International application number: PCT/GB2005/000862 (87) International publication number: WO 2005/085559 (15.09.2005 Gazette 2005/37)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR (30) Priority: 05.03.2004 GB 0405062 (71) Applicant: British Waterways Board Watford WD17 4QA (GB)	(72) Inventors: CLAYTON, Richard Watford WD17 4QA (GB) HAMES, Stephen Leeds LS9 8PB (GB) (74) Representative: Thomson, Neil David et al Boult Wade Tennant Verulam Gardens 70 Gray's Inn Road London WC1X 8BT London WC1X 8BT (GB)