(Discussed in detail in the documentary series Industrial Revelation Episode 4.)
In effect the 5-rise consists of five locks connected together with (as always with a staircase) no intermediate "pounds": the lower gate of each chamber forms the upper gate of the chamber below. There are therefore five chambers, and six gates (the top and bottom gates and four intermediate gates). As the Leeds Liverpool canal is a wide canal, the chambers are 14 feet wide, and each "gate" consists of two half-gates, "hinged" from opposite sides of the canal. Each half gate is slightly more than 7 feet wide, so that the two halves close in a "V" shape (pointing "upstream"). Water pressure on the "uphill" side of the gate thus keeps it tightly closed until the water levels on either side are equal, when the gate can be opened and the boat moved to the next chamber (see canal locks for more information on how a lock is constructed and operated).
The 5-rise is the steepest flight of lock in the UK, with a gradient of about 1:5 (a rise of 59ft 2in over a distance of 320ft). The intermediate and bottom gates are the tallest in the country. Because of the complicaitions of working a staircase lock, and because so many boaters (both first-time hirers and new owners) are inexperienced, a full-time lockkeeper is employed, and the locks are padlocked "out of hours". Barry, the "locky", after twenty years based here is now almost infamous on the local canals: he has been nominated for a CBE.
It opened on March 21, 1774 and was a major feat of engineering at the time. When the locks and therefore the canal from Gargrave to Leeds was opened in 1774 a crowd of 30,000 people turned out to celebrate it! The first boat to use the locks took just 28 minutes and the whole first trip is described here as it was in a newspaper of the time - the Leeds Intelligencer. The smaller Three Rise opened at the same time just a few hundred meters further down.
By kjfitz @ 2006-10-21 00:15:40