This report aims to shift the investment needs debate away from a simple focus on spending more towards spending better on the right objectives using relevant metrics. It does so by offering a careful and systematic approach to estimating the funding needs (capital and operations and maintenance) to close the service gap in water and sanitation, transportation, electricity, irrigation, and flood protection. By exploring thousands of scenarios, this report finds that developing country infrastructure could cost anywhere from 2 to 8 percent of GDP per year by 2030 depending on service goals and policy choices.
The report also identifies a policy mix that will enable countries to achieve key international goals - universal access to water, sanitation, and electricity; greater mobility; improved food security; better protection from floods; and eventual full decarbonization - while limiting spending to 4.5 percent of GDP per year on new infrastructure. Importantly, the exploration of thousands of scenarios shows that infrastructure investment paths compatible with the goals of the Paris Agreement cost the same as more polluting alternatives. Decarbonization goals are not a major driver of costs relative to the other cost drivers we explored. Investment needs remain at 2 to 8 percent of GDP when only the scenarios that achieve climate change stabilization at 2 degrees are looked at. The actual amount depends on the quality and quantity of services aimed for, the timing of investments, construction costs, and complementary policies. Finally, investing in infrastructure is not enough - maintaining it is key. Improving services requires much more than capital expenditure, Ensuring a steady flow of resources for operations and maintenance is a necessary condition for success. Good maintenance also generates substantial savings, by reducing the total lifecycle cost of transport and water and sanitation infrastructure by more than 50 percent.