The game was further marred by an incident just after the hour when home No 8 Njike Tchakoute was red carded for punching Jon Boatman and then Carlo Robinson was red carded for encroaching on the pitch after leaving the sin-bin to join the melee.
The West prop was one of the players to have answered the call from the coaches when there was a host of late call-offs for the last away game of the season.
Scrum half Andrew Foreman went down ill and was replaced by the veteran Davy Tighe while prop Michael Hogan also cried off to be replaced by Ross Wood. In the backs Zac Southern was drafted onto the wing after Luke Watson had work commitments.
However, Tom Dixon did return after a two match absence.
Despite an early Stu Waites penalty it was no surprise when the hosts raced into a 15-3 in the first quarter of the game. Tries from winger Sean Colbourne and centre James O’Brien giving West an early mountain to climb.
But persistent pressure earned West a string of penalties with Stuart Waites adding three more to his tally before Scott Butcher picked up well and dived in at he corner in the 35th minute to give us a narrow 17-15 lead at the break.
Waterloo started the second half the more lively with O'Brien scoring his second on 43 minutes, followed by his hat trick seven minutes later to give the home side some breathing space at 27-17.
Tom Dixon marked his return by forcing his way over from ten metres just before the hour mark and then followed the incident which saw the two red cards.
The next score went to Loo with flanker Carl Nolan being sent clear to give the home side a ten point lead.
West continued to battle and got the bonus point they deserved when Stu Waites went over on 73 minutes after good work by Greg Edwards and Jon Boatman. The latter had moved to the centre after Andrew Cheslin succumbed to illness and had to leave the pitch
Waterloo: Adam Anderson, James O’Brien, Sean Colbourne, Gary Lunt, Andrew Trotter, Liam Reeve [Jack Weare 75], Tom Holloway, Sean Gibney [Alex Read 75], Alec Croft, Anthony Harvey, Daniel Frost [artin Bell 47], Chris Wolfenden, Ryan McKie, Carl Nolan, Njike Tchakoute.
Tries: James O’Brien [3], Car Nolan [1]
Conversions: James O Brien [1], Sean Colbourne [1].
Penalties Liam Reeve [1]
Red cards: Njike Tchakoute [62]
West: Adam Larkin, Zac Southern [Darren Thomas 60], Greg Edwards, Andrew Cheslin [Alex Barker 60], Scott Butcher, Stuart Waites, Davy Tighe, Ross Wood, Andrew Dixon, Adam Coates [Carl Robinson 50], Andrew Davies, Tom Dixon, Dan Boatman, Jon Boatman, Stephen Stockdale.: Reps not used.
Tries: Scott Butcher, Tom Dixon, Stuart Waites.
Penalties: Stuart Waites [4].
Red Cards: Carl Robinson [62]
Referee Paul Fincken [North Society]