I can point you towards a site that is within spitting distance of Charlie Gairdiner's and the West Leederville St. John of God Hospital.
Sealed roads, pleasant surroundings, good comms, already plumbed for water supply and sewerage, power supply can be sorted pretty quick - and coincidentally - already earmarked by the W.A. Govt. as the site for an emergency "refugee" camp in case fire/flood/sky falling finds us needing somewhere to stash a few thousand people at short-ish notice.
1994/95 The Scouts held a jamboree at Perry Lakes - 12500ish Scouts under canvas, and part of the deal of having use of the site was that the upgraded water supply and sewer system was to be left in place.
It took us less than 10 days to fence the whole place, set up freezers, bulk stores and transport, set up and commission our pre-made ablution blocks. [nothing fancy- but cheap!!]
Between the local Scouts and Seventh Day Adventist Church we had 90% of the canvas set up for the admin areas, international arrivals and most of the interstate troops within 3 days.
Some of the power was run from the [upgraded] existing supply, with other areas using industrial sized gen-sets.
When we packed up the site, the sewer points were sealed and buried - with a steel plough disk or similar about 300mm underground to protect the junction and to make them easy to find with a metal detector.
Water supply and drainage points were decommissioned in a similar manner - with a fair sprinkling of the water supply points left as potable water taps for park users and drinking fountains.
Part of the site is now gone - [developers strike again] but it could still possibly cater for a couple of thousand in "donga style" accommodation - as long as the local gentry didn't complain too much.