For example:Site 1 has no access to flowing water but construction costs are less than half that of site 2 which which has creek fed alluvial land.

Site1 is in an area with bore water or perhaps it has significantly consistent rainfall.

Site 2 has a soil type that makes dam construction difficult while site 1 has good clay content etc. etc.

The potential trade-offs can be further assessed by seeking out local knowledge and consulting with, possibly, local earthmovers, Soil Conservation, Local Councils and or Water Resources.