, telecommunications could stimulate telework and migration to rural areas, which would produce secondary effects on other infrastructure such as electricity distribution. Overall, substitution has the potential to bring economies in budgetary and efficiency terms in two cases: A) Where telecommunications may substitute for physical infrastructure: Reduce usage and need for private and public transport. Lower demand for roads expansion. Reduce demand for airports, ground infrastructure, flights and ATC expansion. INFRASTRUCTURE TO 2030: TELECOM, LAND TRANSPORT, WATER AND ELECTRICITY - ISBN 92-64-02398-4 © OECD 2. TELECOMS INFRASTRUCTURE TO 2030 Reduce consumption of vehicle hydrocarbon fuels and need for their distribution networks, and subsequent pollution from direct and indirect causes. Redistribute land usage, reducing urban concentration, attached transport and land use demands. B) Where telecommunications may augment or extend infrastructure services: Reduce health care and elderly care spend yet improve quality. Expand educational reach, by distance, age, variety of subjects and materials, for same spend. Improve emergency services in efficiency and cost. Clearly telecoms substitution will not reduce spend on all types of infrastructure. In practice, it may reduce expenditure on some types of infrastructure and could extend the reach of, or reduce, spend on infrastructure services. But for some elements it might expand the demand for infrastructure, for instance, through increased productivity and stimulation of additional activities. The figure below summarises the substitution and secondary effects on other infrastructure elements. Figure 2.24. Main branches or relevance tree Primary substitution Infrastructure effects Secondary effects Utilities and energy Electricity Supply chain Fuels Support services Production equipment Water Finished parts Sewage Raw materials Telecommunications Fine chemical substitution Services Bulk chemicals Insurance Finished metals Travel to work Repairs and maintenance Commu