The home side always had support to the loose ball, with the backs looking dangerous whenever they had possession.
Heriot led 20-12 at halftime, and looked as though it would run away with the game, but Clutha came back with a try in the first minute of the second spell.
Heriot regained control by scoring three tries in the space of 10 minutes, though Clutha responded with a try to outstanding fullback Tyler Bichan, who outpaced everyone in a sprint to the line.
That was the last hint of a comeback, however, as Heriot rattled on another couple of tries to seal its first title since 1994.
For Heriot, Aaron Kimura starred at second five-eighth, scoring 31 points. He ran the backline, punched holes and darted through the gaps, and set up his outside men brilliantly.
Inside backs Jye Cormack and Adrian Clague both had fine games, distributing the ball nicely. Bill Maiono scored the opening try, which had the Heriot fans on their toes, but he was otherwise kept quiet by some fine Clutha tackling.
The Heriot front row performed superbly, while Ash Kinaston took good lineout ball. Nathan Stuart led the loose trio, and had full support from Shaun Tauti and Brad Lapthorne.
For Clutha, Bichan was supreme, running well with the ball in hand and showing super pace. Rhys Harrold (first five) and Cam Young (halfback) were both steady.
Simon Grant led the loose forwards, but they had to defend more than attack.
By Norman Woods.
South Otago
Club rugby final
Heriot 52
Aaron Kimura 2, Bill Maiono, Craig Stanway, Shaun Tauti, Nathan Park, Richard Redditt tries; Kimura 4 con, 3 pen
Clutha 24
Tyler Bichan 2, Chris Roxburgh, Rhys Harrold tries; Harrold 2 con
Halftime: Heriot 20-12.
