The Watermill/Behind the Scenes

Television Series
The Watermill is a fictional mill on the Island of Sodor created by Britt Allcroft and David Mitton. It is situated north of Elsbridge on Thomas' Branch Line.

The Watermill first appeared in the second series of the television series, in the episode Percy and Harold, which first aired in 1989. Its last appearance was in the twenty-second series episode The Water Wheel, which aired in 2018.

The watermill has appeared in the opening credits for the sixth series, and from the eighth to eighteenth series.

Gauge 1 models
The first model of the watermill was constructed for the second series. The watermill and bridge were inspired by Daniels Mill along the Severn Valley Railway

CGI model
In 2009, the series introduced Computer-Generated Imagery (CGI) as a replacement for the show's long-standing live-action models. The Watermill was recreated from scratch in CGI by Nitrogen Studios. The model was "hand-sculpted" in Maya, a 3D animation and modelling software. The design is based on the model used from the sixth series to the twelfth series.

According to Greg Tiernan, the CGI models are subjected to many rounds of review before they are submitted to HiT Entertainment for final input and approval.