This slide shows the design of Griffiths, Coulter and Caswell for drainage and sewerage as per their submission to the Federal Capital City Design Competition.
Although they did not win the competition, their plan for drainage and sewerage was purchased and then incorporated into the design process for Canberra.
In this slide that drainage plan is overlaid on Walter Burley Griffin's Preliminary Plan. Visible are the rising main, the main gravitational sewer, pumping station and dam.
The parklands surrounding the lake are indicated by areas full of small dots. The yellow areas on the slide indicate the floodplains, the low-lying areas with the potential to flood in times of high rainfall.