Drowning by Numbers inverts this process, and instead uses the language of mapping (Eastings and Northings from GPS tracking of exploratory wanderings in an area), to re-create images of that specific place, as it has changed over a period of eighteen months. The area depicted is a drowned river valley above a Hydro dam on the Upper Derwent. The lake supply level varies seasonally according to rainfall and electricity usage, alternately draining and drowning the land. The art-work is constantly being generated by a computer program written in an open source java programming environment called "Processing". Thus the program builds each image differently every time, whilst also changing the overall order of the images."