An Infrastructure Potential Cost Model for Integrated Land Use and Infrastructure Planning

A strategic bulk infrastructure potential cost model has been developed as a decision support tool for planners and development decision-makers to ensure the proactive incorporation of bulk infrastructure cost considerations in the early land suitability assessment phase of the integrated planning process, to enhance the integration of land use and infrastructure planning. Not only does the model inform the early stages of the planning process prior to any proposals being made, but can also be adapted and applied in the plan evaluation stage, at a strategic level in situations where time, technical capacity, optimisation models andfunds are limited or even lacking. Bulk engineering services infrastructure relating to water, sanitation and electricity have been included in the model. Potential costs are calculated on the basis of capacity in the existing system and include additional cost factors such as geotechnical, land use and environmental conditions to further enhance cost accuracy. The output of the model is in the form of potential cost contours which facilitates the relative comparison of infrastructure costs for different density scenarios. Within a rapidly changing planning environment, it was found that although the model output was accepted at the time, before the output could be incorporated into the larger planning process, planning officials, decision-makers and the process itself had changed. This reinforces the importance ofplanning support systems (PSS) being integrally related to the planning process they are supporting if the outcomes are to have more than just an academic result. If the implementation structures are not in place andfunctioning, the PSS in isolation is not useful in influencing decision-making.