As well as a negative association with wells, there is a very high number of household water tanks shown in the 1933 sewerage plans for the areas associated with Tertiary deposits. These tanks could not be imported to the area before the construction of the railway in 1890 (?). Their presence therefore reflects post-1890 development. Soon after this also, the introduction of reticulated water presented another potential water source.

The result of these two innovations is that urban development was uncoupled from the geological constraints enforced by wells. From the 1933 sewerage plans, it can be seen that may areas devoid of wells in the Tertiary deposits show development to the same intensity as those associated with alluvium. This is despite the alluvium development having potentially several decades longer to accumulate. This rapid development demonstrates that water was indeed the inhibiting factor in the spatial distribution of early Armidale.