After dreadnaught it was on to 'Rednaught' which should probably be called 'The Malago Storm Interceptor' - It gets its rednaught name from the more typical red brick construction. It probably dates from around the 1860's. After a cholera epidemic in 1848 the council set about putting in place a proper sewage and drainage system. The vast majority of which still serves the population of Bristol today..
More here:
http://www.whateversleft.co.uk/index...drain-bristol/