The Buddies were leading 2-0 thanks to goals from Paul McGowan and Steven Thompson in a seven-minute spell during the opening half.
Second-bottom St Mirren would have moved three places up the table with a victory, but Lennon was pragmatic over the official's decision.
"It's frustrating because we saw the other results and we could have capitalised on results elsewhere to move a couple of places up the table," Lennon said.
"You make your own luck in this game and we can't control the weather or the decisions that officials make. I totally respect the referee and that he took the decision thinking about the health and safety of the players.
"The downpour in the last couple of hours was a freak of nature. In four seasons at this football club I've never seen the pitch in that condition.
"Even at the end of the first half the water was starting to lie on it and the players were having to be firmer with their passes.
"At half-time I warned our players that any pass-backs to the keeper had to be hit that bit harder. I thought the decision to bring the players off was correct at the time.
"It's a difficult situation for the referee. One manager wants the game to go on and the other wants it stopped."
County manager Derek Adams feels Collum's judgement was correct, but concedes the visitors were fortunate.
"I think, with the rain still coming down, it's the correct decision but the result is better for us that it is for St Mirren," Adams said.
"It's a difficult decision for Willie Collum to make but I believe from a football perspective it's the right decision. However, we got out of jail today.
"The referee is at St Mirren and he's got a difficult decision to make. He's got the home fans who want the game to go ahead and so do the St Mirren people so it's a brave decision, even though it's the right one."